Valve-in-valve TAVR outcomes favorable to native valve procedures
Valve-in-valve TAVR (ViV-TAVR) of a failed surgical valve was associated with comparable—and perhaps even better—clinical outcomes when compared to TAVR performed in native valves, according to a registry study published in the Journal of the American College of Cardiology.
Lead author E. Murat Tuzcu, MD, and colleagues matched 1,150 patients undergoing ViV-TAVR to twice as many patients undergoing conventional TAVR based on age, reoperation risk level and five-meter walk time. However, there were other differences between the groups, including a greater burden of heart failure symptoms and mitral or tricuspid regurgitation among the ViV-TAVR group and older age plus higher rates of diabetes and coronary artery disease in the native valve TAVR (NV-TAVR) group.
ViV-TAVR was associated with lower unadjusted rates of 30-day mortality (2.9 versus 4.8 percent), stroke (1.7 versus 3 percent) and heart failure hospitalizations (2.4 versus 4.6 percent). Upon multivariable adjustment, ViV-TAVR was linked to mortality reductions of 50 and 35 percent at 30 days and one year, respectively, compared to the native valve procedures.
Echocardiographic analyses revealed higher post-TAVR mean gradients among the valve-in-valve group, particularly for patients with smaller bioprosthetic valves.
“These findings suggest that symptomatic patients with degenerated surgically placed aortic prostheses who are at high risk for conventional surgery do reasonably well after a successful ViV-TAVR,” Tuzcu et al. wrote. “The differences in the post-procedure outcomes between the ViV and NV-TAVR groups including higher frequency of atrial fibrillation, need for new permanent pacemaker, vascular complications requiring intervention, and major bleeding in the NV-TAVR group might have contributed to the diverging mortality curves between the two groups.”
Tuzcu et al. noted it is unlikely a significant number of patients would be enrolled in a trial of redo surgical aortic valve replacement based on their prohibitive risk of surgery. This would provide the best comparator for ViV-TAVR, they acknowledged, but the authors chose to evaluate ViV-TAVR against the measuring stick of conventional TAVR. However, they cautioned against a direct comparison of the two procedures as they are performed in patient populations at “mutually exclusive” disease states.
“Our purpose in comparing the two procedures was not to find out which one is superior in safety and efficacy. Rather, we wanted to see if ViV-TAVR is comparable in safety and effectiveness in high-risk patients with the benchmark procedure NV-TAVR,” the authors explained. “NV-TAVR was chosen as a comparator because its value has been proven in multiple randomized clinical trials, and its extensive use in clinical practice has been documented with real-world registries.”
Tuzcu and coauthors concluded that the outcomes of the valve-in-valve procedure “are within the bounds of clinical acceptability and justify this treatment being the favored approach in these patients.”
The authors of an accompanying editorial said it is “remarkable” how quickly ViV-TAVR has evolved considering it was first described in 2007. But even though early returns of the technique are promising, they added longer follow-up is required to fully assess its potential limitations.
“There are uncertainties about coronary access and obstruction, residual stenosis, thrombosis, and durability,” wrote John G. Webb, MD, Dale Murdoch, MD, and Danny Dvir, MD. “However, the appeal of a minimally invasive procedure with favorable early clinical and functional outcomes means that transcatheter valves will likely become the chosen strategy for many, and perhaps most, patients with failed bioprosthetic valves.”
Daniel joined TriMed’s Chicago editorial team in 2017 as a Cardiovascular Business writer. He previously worked as a writer for daily newspapers in North Dakota and Indiana.