Study: SAVR mortality predicts TAVR outcomes in US hospitals

Hospitals with favorable outcomes for surgical aortic valve replacement (SAVR) procedures subsequently see better transcatheter aortic valve replacement (TAVR) outcomes when they launch TAVR programs, researchers reported in JAMA Cardiology Dec. 5, suggesting the quality of an institution’s surgical team could be an indicator of how they’ll fare after they initiate TAVR.

While SAVR was long the gold standard for treating severe aortic valve disease, today TAVR interventions eclipse SAVR procedures in both the U.S. and Europe, Robert W. Yeh, MD, MSc, and co-authors wrote.

“It is likely that the involvement of surgeons and surgical intensive care units may have strong effects on the evaluation, procedural care and post-procedural management of patients undergoing TAVR procedures,” they said. “Because of the importance of cardiac surgical care and setting in the performance of TAVR, we hypothesized that the existence of higher-quality surgical programs may have been associated with better outcomes on their establishment of new TAVR programs.”

Yeh and his team at Beth Israel Deaconess Medical Center launched a national cohort study using information from CMS’ Medicare Provider and Review database, considering data collected between 2010 and 2015. Hospitals had to have performed at least one SAVR before Sept. 1, 2011, and one TAVR after that date to qualify for the study.

A total of 51,924 TAVR procedures spanning 519 hospitals were included in the analysis. Thirty-eight percent of those procedures were performed at quartile 1 hospitals (hospitals with the lowest risk-adjusted SAVR mortality rate), 15 percent were performed at quartile 2 hospitals, 20 percent were performed at quartile 3 hospitals and 27 percent were performed at quartile 4 hospitals (those with the highest risk-adjusted SAVR mortality rate). Yeh et al. used hospital risk-adjusted 30-day mortality data for SAVR in the hospital’s pre-TAVR period as a surrogate for SAVR quality.

The team found that TAVR mortality rates at 30 days increased alongside a hospital’s baseline SAVR risk-adjusted mortality. One-month mortality was 4.6 percent in quartile 1, 5 percent in quartile 2, 5.1 percent in quartile 3 and 5.6 percent in quartile 4. One-year mortality followed that pattern, with death rates of 17 percent, 17.5 percent, 18.2 percent and 18.6 percent for each quartile, respectively.

The authors concluded that hospitals with higher SAVR mortality rates in turn had higher short- and long-term TAVR mortality rates, suggesting a hospital’s quality of surgical care can similarly impact the outcomes of both procedures. In a related editorial, John D. Carroll, MD, of the University of Colorado School of Medicine, said the researchers’ results weren’t all that surprising.

“Perhaps a more important question that subsequently arises is why this association exists,” he wrote.

He lauded Yeh et al. for their work but said their use of CMS data likely limited the study pool to patients of comparable socioeconomic status and education level, rather than considering local hospitals that serve more niche populations.

“Indeed, it is very important to sort out the potential influence of these factors on the results of outcome-focused studies such as this one to avoid unintended consequences of changing site and clinician requirements,” Carroll wrote. “Populations with known healthcare disparities in the United States may have additional barriers to accessing TAVR and SAVR, and their outcomes may be adversely affected by social determinants that have nothing to do with the skills and experience of the local heart team.”