Technical and procedural success rates for chronic total occlusion percutaneous coronary intervention (CTO PCI) have increased steadily over the past 6 years, with rates of in-hospital major adverse cardiac events (MACE) declining to the 2%-or-lower range in that time.
“CTO PCI technical and procedural success rates are high and continue to increase over time,” Spyridon Kostantinis, MD said in presenting updated results from the international PROGRESS-CTO registry at the Society for Cardiovascular Angiography & Interventions annual scientific sessions.
Courtesy Minneapolis Heart Institute Foundation
Dr. Spyridon Kostantinis
“The overall success rate increased from 81.6% in 2018 to 88.1% in 2021,” he added. The overall incidence of in-hospital MACE in that time was “an acceptable” 2.1% without significant changes over that period.
The analysis examined clinical, angiographic and procedural outcomes of 10,249 CTO PCIs performed on 10,019 patients from 63 centers in nine countries during 2016-2021. PROGRESS-CTO stands for Prospective Global Registry for the Study of Chronic Total Occlusion Intervention.
The target CTOs were highly complex, he said, with an average J-CTO (multicenter CTO registry in Japan) score of 2.4 ± 1.3 and PROGRESS-CTO score of 1.3 ± 1. The most common CTO target vessel was the right coronary artery (53%), followed by the left anterior descending artery (26%) and the circumflex artery (19%).
The registry also tracked how characteristics of the CTO PCI procedures themselves changed over time. “The septal and the epicardial collaterals were the most common collaterals used for retrograde crossing, with a decreasing trend for epicardial collaterals over time,” said Dr. Kostantinis, a research fellow at the Minneapolis Heart Institute.
Septal collateral use varied between 64% and 69% of cases from 2016 to 2021, but the share of epicardial collaterals declined from 35% to 22% in that time.
“Over time, the range of antegrade wiring as the final successfully crossing strategy increased from 46% in 2016 to 61% in 2021, with a decrease in antegrade dissection and re-entry (ADR) and no change in the retrograde approach,” Dr. Kostantinis said. The percentage of procedures using ADR as the final crossing strategy declined from 18% in 2016 to 12% in 2021, with the rate of retrograde crossings peaking at 21% in 2016 but leveling off to 18% or 19% in the subsequent years.
“An increasing use in the efficiency of antegrade wiring may reflect an improvement in guidewire retrograde crossing as well as the increasing operator expertise,” Dr. Kostantinis said.
The study also found that contrast volume, air kerma radiation dose, fluoroscopy time, and procedure time declined steadily over time. “The potential explanations for these are using new x-ray systems as well as the use of intravascular imaging,” Dr. Kostantinis said.
In 2020, the rates of technical and procedural success, as well as the number of overall procedures, declined from 2019, while MACE rates ticked upward that year, probably because of the COVID-19 pandemic, Dr. Kostantinis said.
“It is true that we noticed a rise in MACE rate from 1.6% in 2019 to 2.7% in 2020, but in 2021 that decreased again to 1.7%,” he said in an interview. “Another potential explanation is the higher angiographic complexity of CTOs treated during that year (2020) that resulted in more adverse events.”
Previous results from the PROGRESS-CTO registry reported the difference in MACE between 2019 and 2020 was significant (P = .01). “So, yes, the difference between those 2 years is significant,” Dr. Kostantinis said. However, he noted, the overall trend was not significant, with a P value of .194.
The risk profile of CTO PCI has improved “slowly” over time, said Kirk N. Garratt, MD, but “it’s not yet were it needs to be.”
Dr. Kirk N. Garratt
He added, “Undoubtedly we’ve learned that, without any question, one method for minimizing the risk is to concentrate these cases in the hands of those that do many of them.” As the number of procedures fell – an “embedded” pandemic impact –“I worry that it’s inevitable that complication rates will tick up a bit,” said Dr. Garratt, director of the Center for Heart and Vascular Health at Christiana Care in Newark, Del.
By the same token, he added, this situation with regard to CTOs “parallels what’s happening elsewhere in interventional medicine and medicine broadly; numbers are increasing and we’re busy again. In most domains we’re not as busy as we had been prepandemic, and time will allow us to catch up.”
PROGRESS-CTO has received funding from the Joseph F. and Mary M. Fleischhacker Foundation and the Abbott Northwestern Hospital Foundation Innovation Grant.
Dr. Kostantinis has no disclosures. Dr. Garratt is an advisory board member for Abbott.