Trial results show mortality rates following TAVR decreased over time

Patients enrolled in a major clinical trial who underwent transfemoral transcatheter aortic valve replacement (TF-TAVR) in late 2011/early 2012 had significant declines in 1- and 2-year all-cause mortality compared with those who had the procedure performed earlier.

Lead researcher Nirat Beohar, MD, of Columbia University in New York, and colleagues published their results online in the Journal of the American College of Cardiology: Cardiovascular Interventions on Jan. 20.

“The significant decline in all-cause 1- and 2-year morality found in the present analysis was likely multifactorial, with causes including the enrollment of patients with more favorable clinical risk profiles over the course of the [study’s] enrollment period,” they wrote. “Reducing late (1- and 2- year) mortality after TF-TAVR is highly dependent on strategic case selection, the enrollment of patients with fewer high-risk characteristics, and avoidance of ‘futile’ patients, lowering the frequency of moderate/ severe periprocedural [paravalvular regurgitation] and reducing nonfatal major procedural complications.”

The researchers noted that more than 100,000 TAVR procedures were performed between 2002 and 2013 and that the numbers have increased in recent years as operators and heart teams become more experienced.

In this study, the researchers evaluated 1,063 patients with severe native trileaflet aortic stenosis who were part of the PARTNER (Placement of Aortic Transcatheter Valves) trial’s nonrandomized continued access registry. They divided patients into three groups based on the date of their procedure: March 24, 2009, to July 21, 2010 (tertile 1); July 22, 2010, to March 10, 2011 (tertile 2); and March 11, 2011, to January 10, 2012 (tertile 3).

All patients underwent a TAVR procedure using a 23- or 26-mm balloon-expandable Sapien transcatheter heart valve (Edwards Lifesciences). They also underwent transthoracic echocardiography before discharge as well as at follow-up assessments at 1 month, 6 months and 1 year at an independent laboratory.

Patients in tertile 1 were younger, had a higher mean Society of Thoracic Surgeons predicted risk of mortality and had a higher frequency of prior stroke or transient ischemic attack, porcelain aorta, chronic obstructive pulmonary disease, previous chest wall radiation and chest wall deformities compared with tertile 2 or 3 patients.

There was also a significant decline in the frequency of patients deemed inoperable who underwent TAVR from tertile 1 to 3, according to the researchers. From tertile 1 to 3, there was also a significant decrease in the need for post-dilation after valve placement, a significant increase in the use of fully percutaneous access and a significant decline in the need for surgical cut down for TAVR arterial access.

At 6 months, the all-cause mortality rates were 16.7 percent in tertile 1, 13.9 percent in tertile 2 and 10.2 percent in tertile 3. The all-cause mortality rates at 1 year were 22.7 percent, 21.4 percent and 14.4 percent, respectively, while the all-cause mortality rates at 2 years were 34.9 percent, 32.6 percent and 24.2 percent, respectively.

After 30 days of follow up, there were no significant differences between the groups in terms of stroke, major bleeding, major vascular complications, aortic valve reinterventions or the composite of those nonfatal major complications.

However, the researchers noted that the rates of 30-day post-procedural moderate or severe paravalvular regurgitation were 19.2 percent in tertile 1, 13.8 percent in tertile 2 and 10.1 percent in tertile 3.

After making multiple adjustments, the researchers found that enrollment in tertile 3 was independently associated with a 33 percent decline in all-cause mortality compared with tertile 1. They added that enrollment in tertile 2 was not independently predictive of mortality compared with enrollment in tertile 1.

“The impact of increased operator and institutional experience and evolving technical or procedural enhancements such as improved delivery systems and percutaneous access or closure techniques on all-cause mortality after TAVR were not assessed in this analysis,” the researchers wrote. “The present analysis is a post-hoc analysis from a nonrandomized registry and has inherent limitations related to such an approach.”