LONDON – Hypertrophic cardiomyopathy patients undergoing noncardiac surgery posted significantly worse 30-day composite outcomes than did closely matched controls undergoing the same sorts of surgical procedures.
“Our recommendation is that when hypertrophic cardiomyopathy patients need noncardiac surgery they should be evaluated and treated at an experienced center,” Dr. Milind Y. Desai concluded at the annual congress of the European Society of Cardiology.
There is a dearth of data on outcomes of noncardiac surgery in patients with hypertrophic cardiomyopathy (HCM). This was the impetus for Dr. Desai and his coinvestigators at the Cleveland Clinic to conduct a case-control study involving 92 consecutive adults with HCM undergoing intermediate- or high-cardiovascular-risk noncardiac surgery and 184 controls matched for age, gender, and type of surgery. Enrollment was restricted to HCM patients who hadn’t previously undergone septal myectomy or alcohol ablation.
The primary outcome was the 30-day composite of postoperative death, MI, stroke, or heart failure. The incidence was 10% in the HCM group, significantly greater than the 3% rate in controls. Moreover, 4% of HCM patients developed postoperative atrial fibrillation, compared with none of the controls. Three deaths occurred among the 92 HCM patients, an incidence twice that in the control group.
The special challenge of noncardiac surgery in HCM patients is that their heart condition is characterized by systolic anterior motion of the mitral valve, dynamic left ventricular outflow tract obstruction, diastolic dysfunction, and mitral regurgitation. The rapid blood pressure and fluid shifts that occur during noncardiac surgery require special attention in such patients, Dr. Desai observed.
The HCM patients in this series received such attention, he added. They were more likely than controls to be on beta-blocker therapy at surgery, they received lower doses of ephedrine intraoperatively so as to avoid aggravating outflow tract obstruction, and they spent half as much time as controls with a systolic blood pressure below 90 mm Hg or a heart rate greater than 100 bpm.
“Care was taken to make sure these patients did not decompensate,” he noted.
Dr. Desai reported no financial conflicts regarding this study, conducted free of commercial support.