CHICAGO – During 2009-2012, U.S. interventionalists and surgeons performing transcatheter aortic valve replacements made substantial strides in improving the safety and efficacy of the procedure, cutting first-year mortality rates by about a third, according to a review of more than 1,000 patients treated during that time.
Factors contributing to these gains included patient selection and an increased percentage of patients who emerged from their transcatheter aortic valve replacement (TAVR) procedure with mild, trace, or no paravalvular leak. Other developments that may have boosted patient survival included increased operator experience and changes in the TAVR delivery system, Dr. Nirat Beohar said at the American Heart Association scientific sessions.
“I think most important has been sizing the valve, which seemed to evolve” during the course of the 3-year period studied, said Dr. Beohar, director of the cardiac catheterization laboratory at Mount Sinai Medical Center in Miami Beach.
Mitchel L. Zoler/Frontline Medical News
Dr. Nirat Beohar
His analysis used data collected during the PARTNER continued-access program that allowed centers that had participated in the PARTNER trial, the first U.S. pivotal trial of the SAPIEN TAVR system marketed by Edwards, to continue to offer TAVR to patients during March 2009-January 2012, a period that mostly preceded Food and Drug Administration approval of the SAPIEN system for U.S. use in November 2011.
To assess changes in outcomes over time, Dr. Beohar and his associates divided the 1,063 patients who received TAVR through the continued-access program during this time into three tertiles: The 353 patients who underwent TAVR during March 2009-July 2010, 355 patients treated during July 2010-March 2011, and 355 patients treated during March 2011-January 2012.
Compared with patients treated during the earliest period, those treated during the most recent period were significantly older, with an average age of 86 years versus 84 years at the start of the program. The most recent patients also had a significantly reduced prevalence of comorbidities. For example, chronic obstructive pulmonary disease dropped from a 52% prevalence early to 37% during the most recent period. Patients with a porcelain aorta fell from 7% to 1%, and patients considered inoperable fell from 40% of the first tertile cohort to 8% of the patients in the most recent tertile.
All 1,063 patients in the analysis underwent TAVR using transfemoral access, but the use of fully percutaneous access (as opposed to surgical cutdown access) doubled from 31% during the first period to 62% during the most recent period.
All-cause mortality improved significantly at both 1-year and 2-year follow-up. Patients treated during the first time period, March 2009-July 2010, had a 23% mortality rate after 1 year and 35% after 2 years. During the most recent period studied, March 2011-January 2012, first-year deaths fell to 14%, and mortality was 24% after 2-year follow-up, said Dr. Beohar.
Despite this improvement in survival, the rate of nonfatal major complications during the first 30 days after treatment remained stable, occurring in 17% of patients in the first tertile, 13% in the second tertile, and 15% in the third tertile.
In contrast, the prevalence of moderate or severe paravalvular leak (PVL) following TAVR fell during the entire period studied and appeared to strongly correlate with long-term survival. The prevalence of moderate or severe PVL by 30 days after TAVR was 19% among patients in the first tertile and 10% among those in the third tertile, a statistically significant difference.
In a multivariate analysis that adjusted for several demographic and clinical factors, the appearance of moderate or severe PVL during the 30 days following TAVR was linked with a statistically significant, roughly fourfold increase in the rate of 1-year mortality, Dr. Beohar reported. Other factors that had statistically significant association with 1-year mortality were the occurrence of a nonfatal major complication, which linked with a threefold increased mortality rate; reduced renal function, which was associated with a roughly doubled mortality rate; male sex, which was tied to a nearly doubled mortality rate; and treatment with TAVR during the most recent period, which was linked with an approximately 20% reduction in mortality.
Another factor that distinguished the tertile 1 patients from those treated in tertile 3 was that the prevailing device used during the most recent period was the SAPIEN XT device, while patients treated during the first two tertile periods primarily received treatment using the original SAPIEN TAVR system.
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