American Association for Thoracic Surgery (AATS): Annual Meeting

SAN FRANCISCO – Considerable variation by institution suggests that additional training is needed to standardize radiofrequency ablation of persistent atrial fibrillation in patients undergoing concomitant cardiac surgery, according to a prospective, multicenter study.

"As surgeons we need to take the ‘a fib’ part of the procedure more seriously. There can be a high cure rate," Dr. Ralph J. Damiano Jr. said at the annual meeting of the American Association for Thoracic Surgery.

He and his associates studied 150 consecutive patients with persistent or permanent atrial fibrillation (AF) undergoing irrigated unipolar or bipolar radiofrequency treatment at 15 centers between May 2007 and July 2011. The study protocol included use of the Cox Maze IV lesion set.

Freedom from AF at 6-9 months’ follow-up was a primary efficacy end point of the CURE AF (Concomitant Utilization of Radiofrequency Energy for Atrial Fibrillation) trial; this outcome was achieved by 66% of patients. Just more than half of patients, 53%, were not taking antiarrhythmia medications at this follow-up time, another measure of efficacy.

"The Cox Maze IV procedure performed with irrigated radiofrequency ablation in patients with persistent atrial fibrillation restored the majority of patients to sinus rhythm with a low complication rate," Dr. Damiano said.

There was no statistical difference in efficacy outcomes by AF type. Most of the participants, 75%, had long-standing persistent atrial fibrillation, 22% had persistent AF, and 3% had paroxysmal AF.

The mean patient age was 71 years, 56% were men, and the majority had New York Heart Association (NYHA) class II or III heart failure. The mean duration of AF was 64 months.

The primary safety measure in the study was the major cardiac composite adverse event rate within 30 days. A total 6.6% of participants experienced such an event, although none were device related, Dr. Damiano said. There were no cases of pulmonary vein stenosis, he added. Operative mortality was 4%.

Significant predictors of success, defined as freedom from AF, included shorter duration of the persistent or permanent atrial fibrillation, smaller left atrial diameter, and fewer concomitant cardiac procedures, said Dr. Damiano, a cardiothoracic surgeon at Barnes Jewish Hospital in St. Louis.

As an example, the success rate was 50% when total radiofrequency ablation time was less than 6 minutes. By comparison, success grew to 80% with ablation times of 12 minutes or longer.

Left atrial diameter was the only significant predictor of success that remained on a multivariate analysis. Dr. Damiano and his colleagues found that 69% of patients with a left atrial diameter of 3.0-4.5 cm were free from AF, compared with 36% who had a diameter larger than 6 cm. The overall mean left atrial diameter was 5.2 cm.

There were significant differences in achievement of success among different study centers, including a 33% success rate at one site versus 100% at three other sites, Dr. Damiano said.

"The variability between centers is probably one of the most important findings in this study," study discussant Dr. Niv Add said. He asked: "How would you see moving forward with training and credentialing of surgeons?" Dr. Add is chief of cardiac surgery at Inova Fairfax Hospital, Falls Church, Va.

"We were supposed to perform the exact same procedure in the same way," Dr. Damiano replied. "The surgeons all agreed on the lesion set [but] it’s hard to quantify experience. You can see a huge variation in ablation time, so clearly we were not all performing the same procedure. This variability suggests a need for more effective procedural and device training."

A total 80% of patients had concomitant mitral disease; 58% had heart failure; and 52% had tricuspid disease.

The most common surgical procedure was single valve with or without coronary artery bypass grafting (CABG) in 53%. Double-valve surgery with or without CABG was performed in 30% of patients; CABG in 15%; triple-valve with or without CABG in 1%; and other surgery in 1%.

Intraoperative pulmonary vein isolation was measured using exit block and was achieved for 81% of patients. Radiofrequency ablation was performed using Medtronic’s Cardioblate unipolar or bipolar device. As the device is not yet cleared by the Food and Drug Administration for this indication, such use is considered off label.

Dr. Damiano is a consultant for Medtronic. Medtronic sponsored the trial.

SAN FRANCISCO – Considerable variation by institution suggests that additional training is needed to standardize radiofrequency ablation of persistent atrial fibrillation in patients undergoing concomitant cardiac surgery, according to a prospective, multicenter study.

"As surgeons we need to take the ‘a fib’ part of the procedure more seriously. There can be a high cure rate," Dr. Ralph J. Damiano Jr. said at the annual meeting of the American Association for Thoracic Surgery.

He and his associates studied 150 consecutive patients with persistent or permanent atrial fibrillation (AF) undergoing irrigated unipolar or bipolar radiofrequency treatment at 15 centers between May 2007 and July 2011. The study protocol included use of the Cox Maze IV lesion set.

Freedom from AF at 6-9 months’ follow-up was a primary efficacy end point of the CURE AF (Concomitant Utilization of Radiofrequency Energy for Atrial Fibrillation) trial; this outcome was achieved by 66% of patients. Just more than half of patients, 53%, were not taking antiarrhythmia medications at this follow-up time, another measure of efficacy.

"The Cox Maze IV procedure performed with irrigated radiofrequency ablation in patients with persistent atrial fibrillation restored the majority of patients to sinus rhythm with a low complication rate," Dr. Damiano said.

There was no statistical difference in efficacy outcomes by AF type. Most of the participants, 75%, had long-standing persistent atrial fibrillation, 22% had persistent AF, and 3% had paroxysmal AF.

The mean patient age was 71 years, 56% were men, and the majority had New York Heart Association (NYHA) class II or III heart failure. The mean duration of AF was 64 months.

The primary safety measure in the study was the major cardiac composite adverse event rate within 30 days. A total 6.6% of participants experienced such an event, although none were device related, Dr. Damiano said. There were no cases of pulmonary vein stenosis, he added. Operative mortality was 4%.

Significant predictors of success, defined as freedom from AF, included shorter duration of the persistent or permanent atrial fibrillation, smaller left atrial diameter, and fewer concomitant cardiac procedures, said Dr. Damiano, a cardiothoracic surgeon at Barnes Jewish Hospital in St. Louis.

As an example, the success rate was 50% when total radiofrequency ablation time was less than 6 minutes. By comparison, success grew to 80% with ablation times of 12 minutes or longer.

Left atrial diameter was the only significant predictor of success that remained on a multivariate analysis. Dr. Damiano and his colleagues found that 69% of patients with a left atrial diameter of 3.0-4.5 cm were free from AF, compared with 36% who had a diameter larger than 6 cm. The overall mean left atrial diameter was 5.2 cm.

There were significant differences in achievement of success among different study centers, including a 33% success rate at one site versus 100% at three other sites, Dr. Damiano said.

"The variability between centers is probably one of the most important findings in this study," study discussant Dr. Niv Add said. He asked: "How would you see moving forward with training and credentialing of surgeons?" Dr. Add is chief of cardiac surgery at Inova Fairfax Hospital, Falls Church, Va.

"We were supposed to perform the exact same procedure in the same way," Dr. Damiano replied. "The surgeons all agreed on the lesion set [but] it’s hard to quantify experience. You can see a huge variation in ablation time, so clearly we were not all performing the same procedure. This variability suggests a need for more effective procedural and device training."

A total 80% of patients had concomitant mitral disease; 58% had heart failure; and 52% had tricuspid disease.

The most common surgical procedure was single valve with or without coronary artery bypass grafting (CABG) in 53%. Double-valve surgery with or without CABG was performed in 30% of patients; CABG in 15%; triple-valve with or without CABG in 1%; and other surgery in 1%.

Intraoperative pulmonary vein isolation was measured using exit block and was achieved for 81% of patients. Radiofrequency ablation was performed using Medtronic’s Cardioblate unipolar or bipolar device. As the device is not yet cleared by the Food and Drug Administration for this indication, such use is considered off label.

Dr. Damiano is a consultant for Medtronic. Medtronic sponsored the trial.

SAN FRANCISCO – Considerable variation by institution suggests that additional training is needed to standardize radiofrequency ablation of persistent atrial fibrillation in patients undergoing concomitant cardiac surgery, according to a prospective, multicenter study.

"As surgeons we need to take the ‘a fib’ part of the procedure more seriously. There can be a high cure rate," Dr. Ralph J. Damiano Jr. said at the annual meeting of the American Association for Thoracic Surgery.

He and his associates studied 150 consecutive patients with persistent or permanent atrial fibrillation (AF) undergoing irrigated unipolar or bipolar radiofrequency treatment at 15 centers between May 2007 and July 2011. The study protocol included use of the Cox Maze IV lesion set.

Freedom from AF at 6-9 months’ follow-up was a primary efficacy end point of the CURE AF (Concomitant Utilization of Radiofrequency Energy for Atrial Fibrillation) trial; this outcome was achieved by 66% of patients. Just more than half of patients, 53%, were not taking antiarrhythmia medications at this follow-up time, another measure of efficacy.

"The Cox Maze IV procedure performed with irrigated radiofrequency ablation in patients with persistent atrial fibrillation restored the majority of patients to sinus rhythm with a low complication rate," Dr. Damiano said.

There was no statistical difference in efficacy outcomes by AF type. Most of the participants, 75%, had long-standing persistent atrial fibrillation, 22% had persistent AF, and 3% had paroxysmal AF.

The mean patient age was 71 years, 56% were men, and the majority had New York Heart Association (NYHA) class II or III heart failure. The mean duration of AF was 64 months.

The primary safety measure in the study was the major cardiac composite adverse event rate within 30 days. A total 6.6% of participants experienced such an event, although none were device related, Dr. Damiano said. There were no cases of pulmonary vein stenosis, he added. Operative mortality was 4%.

Significant predictors of success, defined as freedom from AF, included shorter duration of the persistent or permanent atrial fibrillation, smaller left atrial diameter, and fewer concomitant cardiac procedures, said Dr. Damiano, a cardiothoracic surgeon at Barnes Jewish Hospital in St. Louis.

As an example, the success rate was 50% when total radiofrequency ablation time was less than 6 minutes. By comparison, success grew to 80% with ablation times of 12 minutes or longer.

Left atrial diameter was the only significant predictor of success that remained on a multivariate analysis. Dr. Damiano and his colleagues found that 69% of patients with a left atrial diameter of 3.0-4.5 cm were free from AF, compared with 36% who had a diameter larger than 6 cm. The overall mean left atrial diameter was 5.2 cm.

There were significant differences in achievement of success among different study centers, including a 33% success rate at one site versus 100% at three other sites, Dr. Damiano said.

"The variability between centers is probably one of the most important findings in this study," study discussant Dr. Niv Add said. He asked: "How would you see moving forward with training and credentialing of surgeons?" Dr. Add is chief of cardiac surgery at Inova Fairfax Hospital, Falls Church, Va.

"We were supposed to perform the exact same procedure in the same way," Dr. Damiano replied. "The surgeons all agreed on the lesion set [but] it’s hard to quantify experience. You can see a huge variation in ablation time, so clearly we were not all performing the same procedure. This variability suggests a need for more effective procedural and device training."

A total 80% of patients had concomitant mitral disease; 58% had heart failure; and 52% had tricuspid disease.

The most common surgical procedure was single valve with or without coronary artery bypass grafting (CABG) in 53%. Double-valve surgery with or without CABG was performed in 30% of patients; CABG in 15%; triple-valve with or without CABG in 1%; and other surgery in 1%.

Intraoperative pulmonary vein isolation was measured using exit block and was achieved for 81% of patients. Radiofrequency ablation was performed using Medtronic’s Cardioblate unipolar or bipolar device. As the device is not yet cleared by the Food and Drug Administration for this indication, such use is considered off label.

Dr. Damiano is a consultant for Medtronic. Medtronic sponsored the trial.

SAN FRANCISCO – There is no consensus among experts on the optimal surgical approach to repair neonatal hypoplastic left heart syndrome, if a series of consecutive talks at the annual meeting of the American Association for Thoracic Surgery is any indication.

Dr. David J. Barron is a proponent of the placement of a stage 1 right ventricle–pulmonary artery (RV-PA) conduit (Circulation 2003;108[suppl. 1]:II155-60); Dr. J. William Gaynor prefers a stage 1 Blalock-Taussig (BT) shunt; and Dr. Mark E. Galantowicz advocates a hybrid stage 1 procedure.

Dr. Emile A. Bacha tied all these strategies together in a differential approach to management of neonates with hypoplastic left heart syndrome. There may be no one answer; local factors such as surgeon experience or medical center volume can impart significant difference on outcomes, Dr. Bacha said. His bias, in general, is to use the BT shunt for aortic stenosis and the RV-PA conduit for aortic atresia, and to reserve the hybrid approach for high-risk patients. Dr. Bacha is director of the congenital and pediatric cardiac surgery at the Morgan Stanley Children’s Hospital of New York–Presbyterian in New York City.

The surgeons provided the following overview:

• Stage 1 RV-PA conduits. "If you have any condition where there are three different ways to do the same operation, [it indicates that] we are still looking for the right way of doing it. What is important is trying to find the right operation for the right patient," said Dr. Barron, a consultant cardiac surgeon at Birmingham (England) Children’s Hospital.

"It’s all about diastole" with the RV-PA conduit, Dr. Barron said. The maintenance of diastolic pressure is a benefit with RV-PA, compared with the classic Norwood shunt, he added. "When you turn off the shunt in the OR, you get dramatic drop with Norwood where both systolic and diastolic drop. With the RV-PA, the systolic pressure drops but the diastolic pressure is maintained. This facilitates "more of cardiac output to systemic circulation, where you want it to be."

"We’re in an era of evidence-based medicine, and it’s not always easy to find class I evidence in congenital heart disease. The strategy sounds good, but can we actually prove it is better?" Dr. Barron asked. He pointed to a multicenter comparison of 549 infants who were randomized to a modified BT or PA-RV shunt; the study revealed a 10% survival advantage for the PV-RA patients at 1 year (N. Engl. J. Med. 2010:362:1980-92).

A disadvantage of the PV-RA shunt was more catheterization lab interventions (41%, vs. 26% for the modified BT shunt). In addition, the transplantation-free survival advantage was no longer significant after 12 months, he said.

• Stage 1 BTshunts. "We really need to focus on how well these children do over the long run," said Dr. Gaynor, attending cardiothoracic surgeon at the Children’s Hospital of Philadelphia (CHOP).

"Most of the benefit of the RV-PA is in the early interstage period," Dr. Gaynor said. He pointed out that transplant-free survival was not statistically different in the New England Journal of Medicine study at a mean of 32 months’ follow-up.

Dr. Bacha noted that with both speakers using the same study to argue their points," it may be time for a new trial."

Dr. Gaynor suggested that he will remain a proponent of the modified BT shunt until sufficient, long-term evidence supports survival and other advantages with the use of the RV-PA. The RV PA may have some advantages for high-risk subgroups, but more data are needed, he said.

Likewise, an examination of stage 1 reconstruction at CHOP with either the RV-PA or a modified BT shunt showed no significant difference on overall survival, Dr. Gaynor said. (Ann. Thorac. Surg. 2005:80:1582-90). Interestingly, timing made a difference: Patients with the modified BT shunt had significantly higher morbidity during the interstage period, but those with an RV-PA conduit demonstrated a trend toward increased death or transplant for heart failure after stage 2 reconstruction.

• Hybrid stage 1 surgery. "I am in favor of hybrid stage 1 for initial palliation for hypoplastic left heart syndrome. Hybrid stage 1 has at least equivalent results to traditional approaches in standard-risk patients," said Dr. Galantowicz, chief of cardiothoracic surgery at Nationwide Children’s Hospital in Columbus, Ohio.

A hybrid stage 1 can effectively bridge a child to recovery and can salvage a child who was not diagnosed at birth, Dr. Galantowicz said.

There is some evidence that a hybrid approach is less costly overall, compared with placement of a modified BT shunt (Ann. Thorac. Surg. 2009;87:1885-92).

"The standard approach is one of the most costly and resource intensive for any of the congenital children we have," Dr. Galantowicz said. "It requires significant resource utilization, even in the modern era."

Ultimately, "it’s really not about which of these procedures is better as all or nothing. It’s which is better for which subcategory of patient," said Dr. Galantowicz.

According to Dr. Bacha, "I think we can all agree there is equipoise between the BT shunt and the RV-PA conduit, and the hybrid procedures are being increasingly employed for high-risk patients."

Dr. Barron, Dr. Gaynor, Dr. Galantowicz, and Dr. Bacha each said they had no relevant financial disclosures.

SAN FRANCISCO – There is no consensus among experts on the optimal surgical approach to repair neonatal hypoplastic left heart syndrome, if a series of consecutive talks at the annual meeting of the American Association for Thoracic Surgery is any indication.

Dr. David J. Barron is a proponent of the placement of a stage 1 right ventricle–pulmonary artery (RV-PA) conduit (Circulation 2003;108[suppl. 1]:II155-60); Dr. J. William Gaynor prefers a stage 1 Blalock-Taussig (BT) shunt; and Dr. Mark E. Galantowicz advocates a hybrid stage 1 procedure.

Dr. Emile A. Bacha tied all these strategies together in a differential approach to management of neonates with hypoplastic left heart syndrome. There may be no one answer; local factors such as surgeon experience or medical center volume can impart significant difference on outcomes, Dr. Bacha said. His bias, in general, is to use the BT shunt for aortic stenosis and the RV-PA conduit for aortic atresia, and to reserve the hybrid approach for high-risk patients. Dr. Bacha is director of the congenital and pediatric cardiac surgery at the Morgan Stanley Children’s Hospital of New York–Presbyterian in New York City.

The surgeons provided the following overview:

• Stage 1 RV-PA conduits. "If you have any condition where there are three different ways to do the same operation, [it indicates that] we are still looking for the right way of doing it. What is important is trying to find the right operation for the right patient," said Dr. Barron, a consultant cardiac surgeon at Birmingham (England) Children’s Hospital.

"It’s all about diastole" with the RV-PA conduit, Dr. Barron said. The maintenance of diastolic pressure is a benefit with RV-PA, compared with the classic Norwood shunt, he added. "When you turn off the shunt in the OR, you get dramatic drop with Norwood where both systolic and diastolic drop. With the RV-PA, the systolic pressure drops but the diastolic pressure is maintained. This facilitates "more of cardiac output to systemic circulation, where you want it to be."

"We’re in an era of evidence-based medicine, and it’s not always easy to find class I evidence in congenital heart disease. The strategy sounds good, but can we actually prove it is better?" Dr. Barron asked. He pointed to a multicenter comparison of 549 infants who were randomized to a modified BT or PA-RV shunt; the study revealed a 10% survival advantage for the PV-RA patients at 1 year (N. Engl. J. Med. 2010:362:1980-92).

A disadvantage of the PV-RA shunt was more catheterization lab interventions (41%, vs. 26% for the modified BT shunt). In addition, the transplantation-free survival advantage was no longer significant after 12 months, he said.

• Stage 1 BTshunts. "We really need to focus on how well these children do over the long run," said Dr. Gaynor, attending cardiothoracic surgeon at the Children’s Hospital of Philadelphia (CHOP).

"Most of the benefit of the RV-PA is in the early interstage period," Dr. Gaynor said. He pointed out that transplant-free survival was not statistically different in the New England Journal of Medicine study at a mean of 32 months’ follow-up.

Dr. Bacha noted that with both speakers using the same study to argue their points," it may be time for a new trial."

Dr. Gaynor suggested that he will remain a proponent of the modified BT shunt until sufficient, long-term evidence supports survival and other advantages with the use of the RV-PA. The RV PA may have some advantages for high-risk subgroups, but more data are needed, he said.

Likewise, an examination of stage 1 reconstruction at CHOP with either the RV-PA or a modified BT shunt showed no significant difference on overall survival, Dr. Gaynor said. (Ann. Thorac. Surg. 2005:80:1582-90). Interestingly, timing made a difference: Patients with the modified BT shunt had significantly higher morbidity during the interstage period, but those with an RV-PA conduit demonstrated a trend toward increased death or transplant for heart failure after stage 2 reconstruction.

• Hybrid stage 1 surgery. "I am in favor of hybrid stage 1 for initial palliation for hypoplastic left heart syndrome. Hybrid stage 1 has at least equivalent results to traditional approaches in standard-risk patients," said Dr. Galantowicz, chief of cardiothoracic surgery at Nationwide Children’s Hospital in Columbus, Ohio.

A hybrid stage 1 can effectively bridge a child to recovery and can salvage a child who was not diagnosed at birth, Dr. Galantowicz said.

There is some evidence that a hybrid approach is less costly overall, compared with placement of a modified BT shunt (Ann. Thorac. Surg. 2009;87:1885-92).

"The standard approach is one of the most costly and resource intensive for any of the congenital children we have," Dr. Galantowicz said. "It requires significant resource utilization, even in the modern era."

Ultimately, "it’s really not about which of these procedures is better as all or nothing. It’s which is better for which subcategory of patient," said Dr. Galantowicz.

According to Dr. Bacha, "I think we can all agree there is equipoise between the BT shunt and the RV-PA conduit, and the hybrid procedures are being increasingly employed for high-risk patients."

Dr. Barron, Dr. Gaynor, Dr. Galantowicz, and Dr. Bacha each said they had no relevant financial disclosures.

SAN FRANCISCO – There is no consensus among experts on the optimal surgical approach to repair neonatal hypoplastic left heart syndrome, if a series of consecutive talks at the annual meeting of the American Association for Thoracic Surgery is any indication.

Dr. David J. Barron is a proponent of the placement of a stage 1 right ventricle–pulmonary artery (RV-PA) conduit (Circulation 2003;108[suppl. 1]:II155-60); Dr. J. William Gaynor prefers a stage 1 Blalock-Taussig (BT) shunt; and Dr. Mark E. Galantowicz advocates a hybrid stage 1 procedure.

Dr. Emile A. Bacha tied all these strategies together in a differential approach to management of neonates with hypoplastic left heart syndrome. There may be no one answer; local factors such as surgeon experience or medical center volume can impart significant difference on outcomes, Dr. Bacha said. His bias, in general, is to use the BT shunt for aortic stenosis and the RV-PA conduit for aortic atresia, and to reserve the hybrid approach for high-risk patients. Dr. Bacha is director of the congenital and pediatric cardiac surgery at the Morgan Stanley Children’s Hospital of New York–Presbyterian in New York City.

The surgeons provided the following overview:

• Stage 1 RV-PA conduits. "If you have any condition where there are three different ways to do the same operation, [it indicates that] we are still looking for the right way of doing it. What is important is trying to find the right operation for the right patient," said Dr. Barron, a consultant cardiac surgeon at Birmingham (England) Children’s Hospital.

"It’s all about diastole" with the RV-PA conduit, Dr. Barron said. The maintenance of diastolic pressure is a benefit with RV-PA, compared with the classic Norwood shunt, he added. "When you turn off the shunt in the OR, you get dramatic drop with Norwood where both systolic and diastolic drop. With the RV-PA, the systolic pressure drops but the diastolic pressure is maintained. This facilitates "more of cardiac output to systemic circulation, where you want it to be."

"We’re in an era of evidence-based medicine, and it’s not always easy to find class I evidence in congenital heart disease. The strategy sounds good, but can we actually prove it is better?" Dr. Barron asked. He pointed to a multicenter comparison of 549 infants who were randomized to a modified BT or PA-RV shunt; the study revealed a 10% survival advantage for the PV-RA patients at 1 year (N. Engl. J. Med. 2010:362:1980-92).

A disadvantage of the PV-RA shunt was more catheterization lab interventions (41%, vs. 26% for the modified BT shunt). In addition, the transplantation-free survival advantage was no longer significant after 12 months, he said.

• Stage 1 BTshunts. "We really need to focus on how well these children do over the long run," said Dr. Gaynor, attending cardiothoracic surgeon at the Children’s Hospital of Philadelphia (CHOP).

"Most of the benefit of the RV-PA is in the early interstage period," Dr. Gaynor said. He pointed out that transplant-free survival was not statistically different in the New England Journal of Medicine study at a mean of 32 months’ follow-up.

Dr. Bacha noted that with both speakers using the same study to argue their points," it may be time for a new trial."

Dr. Gaynor suggested that he will remain a proponent of the modified BT shunt until sufficient, long-term evidence supports survival and other advantages with the use of the RV-PA. The RV PA may have some advantages for high-risk subgroups, but more data are needed, he said.

Likewise, an examination of stage 1 reconstruction at CHOP with either the RV-PA or a modified BT shunt showed no significant difference on overall survival, Dr. Gaynor said. (Ann. Thorac. Surg. 2005:80:1582-90). Interestingly, timing made a difference: Patients with the modified BT shunt had significantly higher morbidity during the interstage period, but those with an RV-PA conduit demonstrated a trend toward increased death or transplant for heart failure after stage 2 reconstruction.

• Hybrid stage 1 surgery. "I am in favor of hybrid stage 1 for initial palliation for hypoplastic left heart syndrome. Hybrid stage 1 has at least equivalent results to traditional approaches in standard-risk patients," said Dr. Galantowicz, chief of cardiothoracic surgery at Nationwide Children’s Hospital in Columbus, Ohio.

A hybrid stage 1 can effectively bridge a child to recovery and can salvage a child who was not diagnosed at birth, Dr. Galantowicz said.

There is some evidence that a hybrid approach is less costly overall, compared with placement of a modified BT shunt (Ann. Thorac. Surg. 2009;87:1885-92).

"The standard approach is one of the most costly and resource intensive for any of the congenital children we have," Dr. Galantowicz said. "It requires significant resource utilization, even in the modern era."

Ultimately, "it’s really not about which of these procedures is better as all or nothing. It’s which is better for which subcategory of patient," said Dr. Galantowicz.

According to Dr. Bacha, "I think we can all agree there is equipoise between the BT shunt and the RV-PA conduit, and the hybrid procedures are being increasingly employed for high-risk patients."

Dr. Barron, Dr. Gaynor, Dr. Galantowicz, and Dr. Bacha each said they had no relevant financial disclosures.

SAN FRANCISCO – Successful outcomes in 74 of 79 patients who underwent robotic-assisted thymectomy suggest that the technology is safe and feasible, results of a multicenter European study demonstrate.

Dr. Franca Melfi, of the University of Pisa in Italy, and her colleagues studied 79 patients with early thymoma who were surgically treated at multiple centers in Europe between 2002 and 2011. More than half, 45 patients, had myasthenia gravis. The mean operating time was 155 minutes. At last follow-up, 74 patients were still alive and free from recurrence. One patient died of a diffuse intrathoracic recurrence and the others died of causes unrelated to thymoma, Dr. Melfi said at the annual meeting of the American Association for Thoracic Surgery.

Improved depth perception and precise movements facilitated by articulated instruments are among the benefits of the robotic approach. The robot facilitates safe access to the thymus in the upper mediastinal area where the space is small and there are numerous vessels. This approach also allows a prolonged thymectomy when removal of all the fat is required, she explained.

The 608 reported robotic-assisted thymectomies worldwide come from 43 papers published since 2003, but most feature a small number of patients and/or a short follow-up, Dr. Melfi said. One of the few larger studies of robotic-assisted thymectomy included 106 patients with myasthenia gravis (Ann. N.Y. Acad. Sci. 2008:1132:329-35). Researchers in this prospective study reported a mean operative time of 186 minutes, a 1% conversion rate, and a 30-day mortality of 0%. They had a low overall postoperative morbidity rate (2 of 95 patients): one instance of bleeding and one nerve injury.

A greater than 40% complete and stable remission rate for myasthenia gravis was "a real interesting result," Dr. Melfi said, noting that the mean follow-up was 20 months. Most participants reported improved quality of life, she added.

Additional clinical experience and refinements to robotic-assisted thymectomy are warranted, Dr. Melfi said, acknowledging the need for prospective, randomized trials.

Dr. Melfi said she had no relevant financial disclosures.

SAN FRANCISCO – Successful outcomes in 74 of 79 patients who underwent robotic-assisted thymectomy suggest that the technology is safe and feasible, results of a multicenter European study demonstrate.

Dr. Franca Melfi, of the University of Pisa in Italy, and her colleagues studied 79 patients with early thymoma who were surgically treated at multiple centers in Europe between 2002 and 2011. More than half, 45 patients, had myasthenia gravis. The mean operating time was 155 minutes. At last follow-up, 74 patients were still alive and free from recurrence. One patient died of a diffuse intrathoracic recurrence and the others died of causes unrelated to thymoma, Dr. Melfi said at the annual meeting of the American Association for Thoracic Surgery.

Improved depth perception and precise movements facilitated by articulated instruments are among the benefits of the robotic approach. The robot facilitates safe access to the thymus in the upper mediastinal area where the space is small and there are numerous vessels. This approach also allows a prolonged thymectomy when removal of all the fat is required, she explained.

The 608 reported robotic-assisted thymectomies worldwide come from 43 papers published since 2003, but most feature a small number of patients and/or a short follow-up, Dr. Melfi said. One of the few larger studies of robotic-assisted thymectomy included 106 patients with myasthenia gravis (Ann. N.Y. Acad. Sci. 2008:1132:329-35). Researchers in this prospective study reported a mean operative time of 186 minutes, a 1% conversion rate, and a 30-day mortality of 0%. They had a low overall postoperative morbidity rate (2 of 95 patients): one instance of bleeding and one nerve injury.

A greater than 40% complete and stable remission rate for myasthenia gravis was "a real interesting result," Dr. Melfi said, noting that the mean follow-up was 20 months. Most participants reported improved quality of life, she added.

Additional clinical experience and refinements to robotic-assisted thymectomy are warranted, Dr. Melfi said, acknowledging the need for prospective, randomized trials.

Dr. Melfi said she had no relevant financial disclosures.

SAN FRANCISCO – Successful outcomes in 74 of 79 patients who underwent robotic-assisted thymectomy suggest that the technology is safe and feasible, results of a multicenter European study demonstrate.

Dr. Franca Melfi, of the University of Pisa in Italy, and her colleagues studied 79 patients with early thymoma who were surgically treated at multiple centers in Europe between 2002 and 2011. More than half, 45 patients, had myasthenia gravis. The mean operating time was 155 minutes. At last follow-up, 74 patients were still alive and free from recurrence. One patient died of a diffuse intrathoracic recurrence and the others died of causes unrelated to thymoma, Dr. Melfi said at the annual meeting of the American Association for Thoracic Surgery.

Improved depth perception and precise movements facilitated by articulated instruments are among the benefits of the robotic approach. The robot facilitates safe access to the thymus in the upper mediastinal area where the space is small and there are numerous vessels. This approach also allows a prolonged thymectomy when removal of all the fat is required, she explained.

The 608 reported robotic-assisted thymectomies worldwide come from 43 papers published since 2003, but most feature a small number of patients and/or a short follow-up, Dr. Melfi said. One of the few larger studies of robotic-assisted thymectomy included 106 patients with myasthenia gravis (Ann. N.Y. Acad. Sci. 2008:1132:329-35). Researchers in this prospective study reported a mean operative time of 186 minutes, a 1% conversion rate, and a 30-day mortality of 0%. They had a low overall postoperative morbidity rate (2 of 95 patients): one instance of bleeding and one nerve injury.

A greater than 40% complete and stable remission rate for myasthenia gravis was "a real interesting result," Dr. Melfi said, noting that the mean follow-up was 20 months. Most participants reported improved quality of life, she added.

Additional clinical experience and refinements to robotic-assisted thymectomy are warranted, Dr. Melfi said, acknowledging the need for prospective, randomized trials.

Dr. Melfi said she had no relevant financial disclosures.

SAN FRANCISCO – Data from the Interagency Registry for Mechanically Assisted Circulatory Support has identified significant risk factors for death following implantation of left ventricular assist devices as destination therapy. The findings will allow better targeting of patients who can expect 1- and 2-year survival rates on left ventricular assist devices (LVADs) that approach those seen with heart transplantation, according to Dr. James K. Kirklin.

"If we focus on the subset of stable patients without renal or severe right ventricular failure and without previous cardiac surgery, the 2-year survival with a continuous flow device is 80%," said Dr. Kirklin, professor of medicine and director of the division of cardiothoracic surgery at the University of Alabama at Birmingham.

LVAD destination therapy is not appropriate for patients with rapid hemodynamic deterioration, cardiogenic shock, or right ventricular failure, Dr. Kirklin said at the annual meeting of the American Association for Thoracic Surgery. But there is a significant subset of patients who do benefit, including many patients who have advanced heart failure and are not candidates for transplantation.

"Of particular importance is the INTERMACS [Interagency Registry for Mechanically Assisted Circulatory Support] level, which describes subsets of NYHA Class IV patients," Dr. Kirklin said. For example, level 1 describes patients in cardiogenic shock at the time of LVAD implant and was "the most important risk factor for early mortality." Of 112 patients with level 1 designation, 32 died during the study.

Also, right ventricular failure severe enough to require right ventricular assist device support in the same operation was the strongest predictor of mortality in the constant phase (hazard ratio, 3.2).

LVADs are increasingly being used as destination therapy, with LVADs accounting for nearly one-third of all mechanical circulatory support activity in the U.S.

Dr. Kirklin and his colleagues studied 5,407 patients who received a durable ventricular assist device or total artificial heart between June 2006 and December 2011 in the National Heart, Lung, and Blood Institute’s INTERMACS. The 1,287 patients who were not transplant-eligible and received a LVAD for destination therapy comprised the study group.

Significant risk factors for death included older age, larger body mass index, diabetes, a history of coronary artery bypass graft surgery, cardiogenic shock, low sodium, increased bilirubin, and use of a pulsatile flow LVAD, the results of a multivariate analysis indicated.

This is a "timely and important presentation," said invited study discussant Dr. Soon J. Park. "[The researchers] report that a significant percentage of destination therapy patients are achieving a survival rate that is comparable to those who undergo heart transplantation. Such a finding is especially astonishing in that these patients, by definition, were those deemed inappropriate [for] donor hearts. For a significant fraction of patients who were destined to die because heart transplant was not an option for them ... a vast majority will now be able to enjoy life on VAD support." Dr. Park is a cardiovascular surgeon at the Mayo Clinic Transplant Center in Rochester, Minn.

Representative survival after cardiac transplantation from the International Society for Heart and Lung Transplant Registry is approximately 80% at 2 years in a population with generally less comorbidities than the current destination therapy study group, Dr. Kirklin said. Of note, the INTERMACS destination therapy patients were older, a mean of 67 years, compared with 55 years in the transplant reference group. This survival rate of 80% was figured into the multivariate mortality risk factor analysis.

"Heart transplant had been the only option to prolong lives in patients with end-stage heart failure. With recent developments in VAD therapy, heart transplant seems to be the only viable option no longer," Dr. Park said. "VAD therapy can be rendered immediately and abundantly and it is going to change the natural history of end-stage heart failure dramatically, whether [the patient is] transplant eligible or not."

During a discussion that followed presentation of the study results, Dr. John Conte, director of mechanical circulatory support and a professor of surgery at Johns Hopkins Medicine, asked Dr. Kirklin if he is now ready to refer a subset of patients to mechanical support instead of heart transplantation.

"Yes," Dr. Kirklin replied. "I must say the actual identification of patients from the transplant list who could be triaged to mechanical support will depend on their comorbidity. "Remember that the low-risk, 40-year-old patient undergoing cardiac transplantation without other important comorbidities is not the patient one would want to triage to mechanical support. It will only be those patients on the transplant list with multiple, adverse comorbidities that we will initially select for triage."

Dr. Park asked Dr. Kirklin if it would ever make sense to consider VAD as primary therapy and reserve heart transplant as a secondary therapy.

"Of course the goal in the future will be to have an array of therapies which maximize long-term survival for patients, so whether that means initial VAD therapy followed by transplant or initial transplant followed by total artificial heart of course depends upon the rigorous analyses we will need to do in the future," Dr. Kirklin replied.

Although permanent treatment is the intention of destination therapy, the clinical situation may evolve over time and some patients may be considered for cardiac transplantation or device explant, Dr. Kirklin said. "These outcomes can be tracked. In the current era, less than 5% of DT [destination therapy] patients underwent transplant or explant within 2 years."

Dr. Kirklin is the principal investigator of the INTERMACS NHLBI contract.

SAN FRANCISCO – Data from the Interagency Registry for Mechanically Assisted Circulatory Support has identified significant risk factors for death following implantation of left ventricular assist devices as destination therapy. The findings will allow better targeting of patients who can expect 1- and 2-year survival rates on left ventricular assist devices (LVADs) that approach those seen with heart transplantation, according to Dr. James K. Kirklin.

"If we focus on the subset of stable patients without renal or severe right ventricular failure and without previous cardiac surgery, the 2-year survival with a continuous flow device is 80%," said Dr. Kirklin, professor of medicine and director of the division of cardiothoracic surgery at the University of Alabama at Birmingham.

LVAD destination therapy is not appropriate for patients with rapid hemodynamic deterioration, cardiogenic shock, or right ventricular failure, Dr. Kirklin said at the annual meeting of the American Association for Thoracic Surgery. But there is a significant subset of patients who do benefit, including many patients who have advanced heart failure and are not candidates for transplantation.

"Of particular importance is the INTERMACS [Interagency Registry for Mechanically Assisted Circulatory Support] level, which describes subsets of NYHA Class IV patients," Dr. Kirklin said. For example, level 1 describes patients in cardiogenic shock at the time of LVAD implant and was "the most important risk factor for early mortality." Of 112 patients with level 1 designation, 32 died during the study.

Also, right ventricular failure severe enough to require right ventricular assist device support in the same operation was the strongest predictor of mortality in the constant phase (hazard ratio, 3.2).

LVADs are increasingly being used as destination therapy, with LVADs accounting for nearly one-third of all mechanical circulatory support activity in the U.S.

Dr. Kirklin and his colleagues studied 5,407 patients who received a durable ventricular assist device or total artificial heart between June 2006 and December 2011 in the National Heart, Lung, and Blood Institute’s INTERMACS. The 1,287 patients who were not transplant-eligible and received a LVAD for destination therapy comprised the study group.

Significant risk factors for death included older age, larger body mass index, diabetes, a history of coronary artery bypass graft surgery, cardiogenic shock, low sodium, increased bilirubin, and use of a pulsatile flow LVAD, the results of a multivariate analysis indicated.

This is a "timely and important presentation," said invited study discussant Dr. Soon J. Park. "[The researchers] report that a significant percentage of destination therapy patients are achieving a survival rate that is comparable to those who undergo heart transplantation. Such a finding is especially astonishing in that these patients, by definition, were those deemed inappropriate [for] donor hearts. For a significant fraction of patients who were destined to die because heart transplant was not an option for them ... a vast majority will now be able to enjoy life on VAD support." Dr. Park is a cardiovascular surgeon at the Mayo Clinic Transplant Center in Rochester, Minn.

Representative survival after cardiac transplantation from the International Society for Heart and Lung Transplant Registry is approximately 80% at 2 years in a population with generally less comorbidities than the current destination therapy study group, Dr. Kirklin said. Of note, the INTERMACS destination therapy patients were older, a mean of 67 years, compared with 55 years in the transplant reference group. This survival rate of 80% was figured into the multivariate mortality risk factor analysis.

"Heart transplant had been the only option to prolong lives in patients with end-stage heart failure. With recent developments in VAD therapy, heart transplant seems to be the only viable option no longer," Dr. Park said. "VAD therapy can be rendered immediately and abundantly and it is going to change the natural history of end-stage heart failure dramatically, whether [the patient is] transplant eligible or not."

During a discussion that followed presentation of the study results, Dr. John Conte, director of mechanical circulatory support and a professor of surgery at Johns Hopkins Medicine, asked Dr. Kirklin if he is now ready to refer a subset of patients to mechanical support instead of heart transplantation.

"Yes," Dr. Kirklin replied. "I must say the actual identification of patients from the transplant list who could be triaged to mechanical support will depend on their comorbidity. "Remember that the low-risk, 40-year-old patient undergoing cardiac transplantation without other important comorbidities is not the patient one would want to triage to mechanical support. It will only be those patients on the transplant list with multiple, adverse comorbidities that we will initially select for triage."

Dr. Park asked Dr. Kirklin if it would ever make sense to consider VAD as primary therapy and reserve heart transplant as a secondary therapy.

"Of course the goal in the future will be to have an array of therapies which maximize long-term survival for patients, so whether that means initial VAD therapy followed by transplant or initial transplant followed by total artificial heart of course depends upon the rigorous analyses we will need to do in the future," Dr. Kirklin replied.

Although permanent treatment is the intention of destination therapy, the clinical situation may evolve over time and some patients may be considered for cardiac transplantation or device explant, Dr. Kirklin said. "These outcomes can be tracked. In the current era, less than 5% of DT [destination therapy] patients underwent transplant or explant within 2 years."

Dr. Kirklin is the principal investigator of the INTERMACS NHLBI contract.

SAN FRANCISCO – Data from the Interagency Registry for Mechanically Assisted Circulatory Support has identified significant risk factors for death following implantation of left ventricular assist devices as destination therapy. The findings will allow better targeting of patients who can expect 1- and 2-year survival rates on left ventricular assist devices (LVADs) that approach those seen with heart transplantation, according to Dr. James K. Kirklin.

"If we focus on the subset of stable patients without renal or severe right ventricular failure and without previous cardiac surgery, the 2-year survival with a continuous flow device is 80%," said Dr. Kirklin, professor of medicine and director of the division of cardiothoracic surgery at the University of Alabama at Birmingham.

LVAD destination therapy is not appropriate for patients with rapid hemodynamic deterioration, cardiogenic shock, or right ventricular failure, Dr. Kirklin said at the annual meeting of the American Association for Thoracic Surgery. But there is a significant subset of patients who do benefit, including many patients who have advanced heart failure and are not candidates for transplantation.

"Of particular importance is the INTERMACS [Interagency Registry for Mechanically Assisted Circulatory Support] level, which describes subsets of NYHA Class IV patients," Dr. Kirklin said. For example, level 1 describes patients in cardiogenic shock at the time of LVAD implant and was "the most important risk factor for early mortality." Of 112 patients with level 1 designation, 32 died during the study.

Also, right ventricular failure severe enough to require right ventricular assist device support in the same operation was the strongest predictor of mortality in the constant phase (hazard ratio, 3.2).

LVADs are increasingly being used as destination therapy, with LVADs accounting for nearly one-third of all mechanical circulatory support activity in the U.S.

Dr. Kirklin and his colleagues studied 5,407 patients who received a durable ventricular assist device or total artificial heart between June 2006 and December 2011 in the National Heart, Lung, and Blood Institute’s INTERMACS. The 1,287 patients who were not transplant-eligible and received a LVAD for destination therapy comprised the study group.

Significant risk factors for death included older age, larger body mass index, diabetes, a history of coronary artery bypass graft surgery, cardiogenic shock, low sodium, increased bilirubin, and use of a pulsatile flow LVAD, the results of a multivariate analysis indicated.

This is a "timely and important presentation," said invited study discussant Dr. Soon J. Park. "[The researchers] report that a significant percentage of destination therapy patients are achieving a survival rate that is comparable to those who undergo heart transplantation. Such a finding is especially astonishing in that these patients, by definition, were those deemed inappropriate [for] donor hearts. For a significant fraction of patients who were destined to die because heart transplant was not an option for them ... a vast majority will now be able to enjoy life on VAD support." Dr. Park is a cardiovascular surgeon at the Mayo Clinic Transplant Center in Rochester, Minn.

Representative survival after cardiac transplantation from the International Society for Heart and Lung Transplant Registry is approximately 80% at 2 years in a population with generally less comorbidities than the current destination therapy study group, Dr. Kirklin said. Of note, the INTERMACS destination therapy patients were older, a mean of 67 years, compared with 55 years in the transplant reference group. This survival rate of 80% was figured into the multivariate mortality risk factor analysis.

"Heart transplant had been the only option to prolong lives in patients with end-stage heart failure. With recent developments in VAD therapy, heart transplant seems to be the only viable option no longer," Dr. Park said. "VAD therapy can be rendered immediately and abundantly and it is going to change the natural history of end-stage heart failure dramatically, whether [the patient is] transplant eligible or not."

During a discussion that followed presentation of the study results, Dr. John Conte, director of mechanical circulatory support and a professor of surgery at Johns Hopkins Medicine, asked Dr. Kirklin if he is now ready to refer a subset of patients to mechanical support instead of heart transplantation.

"Yes," Dr. Kirklin replied. "I must say the actual identification of patients from the transplant list who could be triaged to mechanical support will depend on their comorbidity. "Remember that the low-risk, 40-year-old patient undergoing cardiac transplantation without other important comorbidities is not the patient one would want to triage to mechanical support. It will only be those patients on the transplant list with multiple, adverse comorbidities that we will initially select for triage."

Dr. Park asked Dr. Kirklin if it would ever make sense to consider VAD as primary therapy and reserve heart transplant as a secondary therapy.

"Of course the goal in the future will be to have an array of therapies which maximize long-term survival for patients, so whether that means initial VAD therapy followed by transplant or initial transplant followed by total artificial heart of course depends upon the rigorous analyses we will need to do in the future," Dr. Kirklin replied.

Although permanent treatment is the intention of destination therapy, the clinical situation may evolve over time and some patients may be considered for cardiac transplantation or device explant, Dr. Kirklin said. "These outcomes can be tracked. In the current era, less than 5% of DT [destination therapy] patients underwent transplant or explant within 2 years."

Dr. Kirklin is the principal investigator of the INTERMACS NHLBI contract.

SAN FRANCISCO – Additional research continues to show good outcomes with a new process that allows successful transplant of lungs that might otherwise be deemed unacceptable.

Researchers at the Organ Regeneration Laboratory at the University of Toronto evaluated and repaired 58 donor lungs over 4-6 hours in a process called normothermic ex vivo lung perfusion (EVLP). In all, 50 of these lungs were successfully transplanted into patients, for a final utilization rate of 86%, Dr. Marcelo Cypel reported at the annual meeting of the American Association for Thoracic Surgery.

The current study builds on a previous report on initial experience with EVLP from the same research team (N. Engl. J. Med. 2011;364:1431-40).

"As we all know, one of the major problems in doing lung transplantation is the organ shortage and the low utilization rates. Only 17% of the lungs from brain death donors and 2% of the lungs from cardiac death donors are used currently," Dr. Cypel said. EVLP lungs accounted for 20% of the transplantations at Toronto General Hospital in 2011.

The EVLP lungs came from 32 brain death donors and 26 cardiac death donors. Dr. Cypel and his colleagues compared the outcomes of these EVLP procedures to another 253 conventional lung transplantations performed at their institution from September 2008 to December 2011.

EVLP patients received a significantly higher percentage of lungs from cardiac death donors, which are generally considered less desirable than lungs from brain death donors. They also received a higher percentage of high-risk lungs from brain death donors (PaO₂/FIO₂ below 300 mm Hg) and more lungs with chest x-ray abnormalities, such as signs of pulmonary edema, compared with the conventional group.

"Donor lungs in the EVLP group were significantly more injured at baseline, however, the outcomes were comparable," said Dr. Cypel, a member of the surgical faculty in the Division of Thoracic Surgery at Toronto General Hospital University Health Network.

For example, posttransplant survival at 1 year was 86% for the EVLP group and 87% for the traditional transplant group in this retrospective study; at 3 years these rates dropped to 70% and 72%. There were no significant differences in survival for patients who received lungs from brain death or cardiac death donors.

Other findings included no significant difference in the rate of primary graft grade 3 dysfunction at 72 hours between groups according to International Society for Heart and Lung Transplantation criteria. The EVLP patients had a trend toward a decreased length of hospital stay, compared with conventional transplant recipients, Dr. Cypel said.

"Again, you and your colleagues have demonstrated the safety and efficacy of using EVLP in the transplantation of lungs that previously would not have been used by your group," said study discussant Dr. R. Duane Davis, director of transplant services at Duke University Health System in Durham, N.C. "Using this technology, we may be able to start applying lung transplant more practically for societal needs."

Dr. Davis asked Dr. Cypel how surgeons at Toronto General Hospital achieved an 86% EVLP utilization rate compared with the 54% rate observed in the U.S. trial and comparable rates in the United Kingdom and elsewhere.

"Our experience with the procedure and extensive laboratory research prior to starting the clinical trial" explain the difference, Dr. Cypel replied. Donor selection criteria also could play a role.

"The important thing is it is taking some of the adventure out of lung transplantation," study coauthor Dr. Shaf Keshavjee said during a separate presentation at the meeting. "Ex vivo lung perfusion is clinically feasible. We can we do a long-term perfusion of lungs outside the body without injuring them. It is possible to keep lung 12 hours outside the body and normothermic."

"We are developing ways to figure out which lungs need a fix and to target treatment to lungs that need treatment," said Dr. Keshavjee, director of the Toronto Lung Transplant program and chair of the Division of Thoracic Surgery at the University of Toronto. Examples include resolution of pulmonary edema and infections through EVLP. Treating infected lungs with lavage and high-dose antibiotics may one day make these organs acceptable for transplantation, even in cases of pneumonia.

The goal is to double or triple the overall number of lung transplants using the EVLP technique in the United States, said Dr. Davis. EVLP comprises 20% of transplants in Toronto, but the overall transplant volume has not increased.

EVLP has allowed the overall number of 100 transplants or so per year in Toronto to remain steady at the same time that organ donation rates have decreased, Dr. Cypel responded.

"The major contribution of EVLP will not be for the large transplant centers like Duke or Toronto, which already use 40% of the organs and for whom a marginal increase is not that large," Dr. Cypel said. "Look at the majority of lung transplant centers that use 10% or less of the offered lungs; that is where we can have a major impact by increasing the number of organs available."

Vitrolife supported the clinical trial. Dr. Cypel and Dr. Keshavjee reported no other relevant disclosures. Dr. Davis said he received research support from Vitrolife for a U.S. study.

SAN FRANCISCO – Additional research continues to show good outcomes with a new process that allows successful transplant of lungs that might otherwise be deemed unacceptable.

Researchers at the Organ Regeneration Laboratory at the University of Toronto evaluated and repaired 58 donor lungs over 4-6 hours in a process called normothermic ex vivo lung perfusion (EVLP). In all, 50 of these lungs were successfully transplanted into patients, for a final utilization rate of 86%, Dr. Marcelo Cypel reported at the annual meeting of the American Association for Thoracic Surgery.

The current study builds on a previous report on initial experience with EVLP from the same research team (N. Engl. J. Med. 2011;364:1431-40).

"As we all know, one of the major problems in doing lung transplantation is the organ shortage and the low utilization rates. Only 17% of the lungs from brain death donors and 2% of the lungs from cardiac death donors are used currently," Dr. Cypel said. EVLP lungs accounted for 20% of the transplantations at Toronto General Hospital in 2011.

The EVLP lungs came from 32 brain death donors and 26 cardiac death donors. Dr. Cypel and his colleagues compared the outcomes of these EVLP procedures to another 253 conventional lung transplantations performed at their institution from September 2008 to December 2011.

EVLP patients received a significantly higher percentage of lungs from cardiac death donors, which are generally considered less desirable than lungs from brain death donors. They also received a higher percentage of high-risk lungs from brain death donors (PaO₂/FIO₂ below 300 mm Hg) and more lungs with chest x-ray abnormalities, such as signs of pulmonary edema, compared with the conventional group.

"Donor lungs in the EVLP group were significantly more injured at baseline, however, the outcomes were comparable," said Dr. Cypel, a member of the surgical faculty in the Division of Thoracic Surgery at Toronto General Hospital University Health Network.

For example, posttransplant survival at 1 year was 86% for the EVLP group and 87% for the traditional transplant group in this retrospective study; at 3 years these rates dropped to 70% and 72%. There were no significant differences in survival for patients who received lungs from brain death or cardiac death donors.

Other findings included no significant difference in the rate of primary graft grade 3 dysfunction at 72 hours between groups according to International Society for Heart and Lung Transplantation criteria. The EVLP patients had a trend toward a decreased length of hospital stay, compared with conventional transplant recipients, Dr. Cypel said.

"Again, you and your colleagues have demonstrated the safety and efficacy of using EVLP in the transplantation of lungs that previously would not have been used by your group," said study discussant Dr. R. Duane Davis, director of transplant services at Duke University Health System in Durham, N.C. "Using this technology, we may be able to start applying lung transplant more practically for societal needs."

Dr. Davis asked Dr. Cypel how surgeons at Toronto General Hospital achieved an 86% EVLP utilization rate compared with the 54% rate observed in the U.S. trial and comparable rates in the United Kingdom and elsewhere.

"Our experience with the procedure and extensive laboratory research prior to starting the clinical trial" explain the difference, Dr. Cypel replied. Donor selection criteria also could play a role.

"The important thing is it is taking some of the adventure out of lung transplantation," study coauthor Dr. Shaf Keshavjee said during a separate presentation at the meeting. "Ex vivo lung perfusion is clinically feasible. We can we do a long-term perfusion of lungs outside the body without injuring them. It is possible to keep lung 12 hours outside the body and normothermic."

"We are developing ways to figure out which lungs need a fix and to target treatment to lungs that need treatment," said Dr. Keshavjee, director of the Toronto Lung Transplant program and chair of the Division of Thoracic Surgery at the University of Toronto. Examples include resolution of pulmonary edema and infections through EVLP. Treating infected lungs with lavage and high-dose antibiotics may one day make these organs acceptable for transplantation, even in cases of pneumonia.

The goal is to double or triple the overall number of lung transplants using the EVLP technique in the United States, said Dr. Davis. EVLP comprises 20% of transplants in Toronto, but the overall transplant volume has not increased.

EVLP has allowed the overall number of 100 transplants or so per year in Toronto to remain steady at the same time that organ donation rates have decreased, Dr. Cypel responded.

"The major contribution of EVLP will not be for the large transplant centers like Duke or Toronto, which already use 40% of the organs and for whom a marginal increase is not that large," Dr. Cypel said. "Look at the majority of lung transplant centers that use 10% or less of the offered lungs; that is where we can have a major impact by increasing the number of organs available."

Vitrolife supported the clinical trial. Dr. Cypel and Dr. Keshavjee reported no other relevant disclosures. Dr. Davis said he received research support from Vitrolife for a U.S. study.

SAN FRANCISCO – Additional research continues to show good outcomes with a new process that allows successful transplant of lungs that might otherwise be deemed unacceptable.

Researchers at the Organ Regeneration Laboratory at the University of Toronto evaluated and repaired 58 donor lungs over 4-6 hours in a process called normothermic ex vivo lung perfusion (EVLP). In all, 50 of these lungs were successfully transplanted into patients, for a final utilization rate of 86%, Dr. Marcelo Cypel reported at the annual meeting of the American Association for Thoracic Surgery.

The current study builds on a previous report on initial experience with EVLP from the same research team (N. Engl. J. Med. 2011;364:1431-40).

"As we all know, one of the major problems in doing lung transplantation is the organ shortage and the low utilization rates. Only 17% of the lungs from brain death donors and 2% of the lungs from cardiac death donors are used currently," Dr. Cypel said. EVLP lungs accounted for 20% of the transplantations at Toronto General Hospital in 2011.

The EVLP lungs came from 32 brain death donors and 26 cardiac death donors. Dr. Cypel and his colleagues compared the outcomes of these EVLP procedures to another 253 conventional lung transplantations performed at their institution from September 2008 to December 2011.

EVLP patients received a significantly higher percentage of lungs from cardiac death donors, which are generally considered less desirable than lungs from brain death donors. They also received a higher percentage of high-risk lungs from brain death donors (PaO₂/FIO₂ below 300 mm Hg) and more lungs with chest x-ray abnormalities, such as signs of pulmonary edema, compared with the conventional group.

"Donor lungs in the EVLP group were significantly more injured at baseline, however, the outcomes were comparable," said Dr. Cypel, a member of the surgical faculty in the Division of Thoracic Surgery at Toronto General Hospital University Health Network.

For example, posttransplant survival at 1 year was 86% for the EVLP group and 87% for the traditional transplant group in this retrospective study; at 3 years these rates dropped to 70% and 72%. There were no significant differences in survival for patients who received lungs from brain death or cardiac death donors.

Other findings included no significant difference in the rate of primary graft grade 3 dysfunction at 72 hours between groups according to International Society for Heart and Lung Transplantation criteria. The EVLP patients had a trend toward a decreased length of hospital stay, compared with conventional transplant recipients, Dr. Cypel said.

"Again, you and your colleagues have demonstrated the safety and efficacy of using EVLP in the transplantation of lungs that previously would not have been used by your group," said study discussant Dr. R. Duane Davis, director of transplant services at Duke University Health System in Durham, N.C. "Using this technology, we may be able to start applying lung transplant more practically for societal needs."

Dr. Davis asked Dr. Cypel how surgeons at Toronto General Hospital achieved an 86% EVLP utilization rate compared with the 54% rate observed in the U.S. trial and comparable rates in the United Kingdom and elsewhere.

"Our experience with the procedure and extensive laboratory research prior to starting the clinical trial" explain the difference, Dr. Cypel replied. Donor selection criteria also could play a role.

"The important thing is it is taking some of the adventure out of lung transplantation," study coauthor Dr. Shaf Keshavjee said during a separate presentation at the meeting. "Ex vivo lung perfusion is clinically feasible. We can we do a long-term perfusion of lungs outside the body without injuring them. It is possible to keep lung 12 hours outside the body and normothermic."

"We are developing ways to figure out which lungs need a fix and to target treatment to lungs that need treatment," said Dr. Keshavjee, director of the Toronto Lung Transplant program and chair of the Division of Thoracic Surgery at the University of Toronto. Examples include resolution of pulmonary edema and infections through EVLP. Treating infected lungs with lavage and high-dose antibiotics may one day make these organs acceptable for transplantation, even in cases of pneumonia.

The goal is to double or triple the overall number of lung transplants using the EVLP technique in the United States, said Dr. Davis. EVLP comprises 20% of transplants in Toronto, but the overall transplant volume has not increased.

EVLP has allowed the overall number of 100 transplants or so per year in Toronto to remain steady at the same time that organ donation rates have decreased, Dr. Cypel responded.

"The major contribution of EVLP will not be for the large transplant centers like Duke or Toronto, which already use 40% of the organs and for whom a marginal increase is not that large," Dr. Cypel said. "Look at the majority of lung transplant centers that use 10% or less of the offered lungs; that is where we can have a major impact by increasing the number of organs available."

Vitrolife supported the clinical trial. Dr. Cypel and Dr. Keshavjee reported no other relevant disclosures. Dr. Davis said he received research support from Vitrolife for a U.S. study.