TAVR associated with better outcomes in high-volume centers

CHICAGO — Centers performing higher volumes of transcatheter aortic valve replacement procedures have better results than those performing lower volumes, according to data from the Society of Thoracic Surgeons/American College of Cardiology TVT Registry.

In United States centers, there is wide variability in TAVR procedure volume (median, 80 per year; interquartile range, 39-154), and some variability in TAVR mortality rates by center (median, 4.03%; interquartile range, 3.75-4.42), John D. Carroll, MD, professor of medicine and director of interventional cardiology at University of Colorado Hospital, Aurora, said during a presentation at the ACC Scientific Session.

John D. Carroll

Carroll and colleagues analyzed 42,988 commercial TAVR procedures documented in the STS/ACC TVT Registry between November 2011 and September 2015 to determine any relationship between center volume and outcomes.

Outcomes of interest included in-hospital mortality, vascular complications, bleeding complications (VARC major bleeding or VARC life-threatening bleeding) and stroke complications.

The sequence of TAVR cases from all centers were stratified into quartiles: one to 30 cases per year, 31 to 71 cases per year, 72 to 137 cases per year and 138 to 602 cases per year. Only 119 of the 395 centers performing TAVR contributed cases into the highest quartile.

Carroll and colleagues reported unadjusted and risk-adjusted outcomes, the latter of which included adjustment for patient characteristics, procedure factors, operator identity and hospital identity.

Carroll said in the presentation that rates of in-hospital mortality (unadjusted P < .0001; risk-adjusted P = .0232), vascular complications (unadjusted P < .0001; risk-adjusted P = .0031) and bleeding complications (unadjusted and risk-adjusted P < .0001) all declined with higher center volume.

However, there was no relationship between stroke complications and center volume (risk-adjusted P = .1399), he said.

Among patients who had TAVR via transfemoral access, vascular complications and bleeding complications declined with higher center volume (unadjusted and risk-adjusted P for both < .0001), but the relationship between center volume and all-cause mortality was attenuated after risk adjustment (unadjusted P < .0001; risk-adjusted P = .1494), he said.

“The volume-outcome relationship for TAVR is both statistically significant and clinically important, and is true for multiple meaningful outcomes analyzed,” Carroll said during the presentation. – by Erik Swain

Reference:

Carroll JD, et al. Joint ACC/TCT Late-Breaking Clinical Trials. Presented at: American College of Cardiology Scientific Session; April 2-4, 2016; Chicago.

Disclosure: Carroll reports receiving research funding from Direct Flow Medical, Edwards Lifesciences and Medtronic, and serving on a Data Safety and Monitoring Board and a Clinical Events Committee for Tendyne.