VARC definitions may help standardize reporting of TAVR outcomes
MedWire News: Using definitions introduced by the Valve Academic Research Consortium (VARC) in 2011 may provide doctors with a uniform method of reporting patient outcomes after transcatheter aortic valve replacement (TAVR), researchers suggest.
"Although VARC definitions have brought uniformity and standardization in reporting outcomes after TAVR, appropriate recognition and ascertaining, reporting and adjudication of outcomes should be reinforced and will ensure that TAVR study results are a valid reflection of 'real-world' clinical events," add the researchers.
Martin Leon (New York-Presbyterian Hospital, USA) and co-investigators performed a meta-analysis of 16 studies involving 3519 patients who had undergone TAVR.
The investigators looked specifically at studies in which post-TAVR outcomes were reported using at least one VARC definition.
As reported in the Journal of the American College of Cardiology, successful functioning of the replaced valve occurred at a pooled estimated rate of 92.1%.
Moderate-to-severe aortic regurgitation, an aortic valve area of less than 1.2 cm2, and failed delivery or implantation of the valve in the correct position were the commonest causes of procedural failure.
All-cause 30-day mortality was reported at rates ranging from 1.7% to 14.3%, with cardiovascular (CV)-related death cited as the commonest cause of 30-day mortality.
VARC definitions state that 30-day and 1-year composite safety outcomes are important endpoints to be reported when assessing TAVR patient outcomes.
The researchers found that the former endpoint was correctly reported in 37.5% of studies analysed and the latter endpoint was correctly reported in only 12.5% of the studies included in the meta-analysis.
Two additional VARC definitions, all-cause mortality at 1 year and CV-related mortality, were reported in 43.8% and 25.0% of the studies, respectively.
Based on their observations, Leon and colleagues surmise that VARC definitions are clearly being used in TAVR-related settings and provide uniformity when assessing post-TAVR outcomes.
They note, however, that the current VARC definitions have limitations, such as ambiguously defined components, which need to be addressed to ensure more widespread use.
Leon and team conclude: "Future revisions of the VARC definitions are needed based on evolving TAVR clinical experiences."
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2012
By Lauretta Ihonor