Despite the improved results with second-generation THV, receipt of a first-generation device was not a significant predictor of mortality at 1 year. Rather, in an analysis of predictors, mortality was significantly increased in those with moderate or worse aortic regurgitation, Society of Thoracic Surgeons risk score of 8% or greater, and acute kidney injury of grade 2 or higher. There was also a trend for increased mortality in those with pulmonary hypertension.
Most of the devices (76%) were placed with a transfemoral approach. No difference in mortality was observed when a transfemoral approach was compared with a nontransfemoral approach.
According to the registry data, a 10%-20% oversizing of the THV was associated with a reduced risk of malpositioning, relative to devices with less than 10% oversizing or greater than 20% oversizing, reinforcing Dr. Dvir’s hypothesis that sizing is a variable affecting outcome in NAVR.
Although Dr. Dvir contended that these data raise issues about the suitability of current THV designs for use in the treatment of NAVR, not all experts were convinced by these data. Jeffrey Popma, MD, director of the interventional cardiology clinical service at Beth Israel Deaconess Hospital, Boston, questioned whether more experience is placing these devices for NAVR might lead to greater success.