Comparison of Outcomes of Balloon-Expandable Versus Self-Expandable Transcatheter Heart Valves for Severe Aortic Stenosis

Transcatheter aortic valve implantation (TAVI) is the treatment of choice for inoperable and high-risk patients with severe aortic stenosis. Our objectives were to elucidate potential differences in clinical outcomes and safety between balloon-expandable versus self-expandable transcatheter heart valves (THV). We performed a retrospective cohort study of all transfemoral TAVI procedures in Ontario, Canada, from 2007 to 2013. Patients were categorized into either balloon-expandable or self-expandable THV groups. The primary outcomes were 30-day and 1-year death, with secondary outcomes of all-cause readmission. Safety outcomes included bleeding, permanent pacemaker implantation, need for a second THV device, postprocedural paravalvular aortic regurgitation, stroke, vascular access complication, and intensive care unit length of stay. Inverse probability of treatment-weighted regression analyses using a propensity score were used to account for differences in baseline confounders. Our cohort consisted of 714 patients, of whom 397 received a self-expandable THV, whereas 317 had a balloon-expandable THV system. There were no differences in death or all-cause readmission. In terms of safety, the self-expandable group was associated with significantly higher rates of inhospital stroke (p value <0.05), need for a second THV device (5.3% vs 2.7%; p value = 0.013), and permanent pacemaker (22.6% vs 8.9%; p value <0.001), whereas the balloon-expandable group had more vascular access site complications (23.1% vs 16.7%; p value = 0.002). Thus, we found similar clinical outcomes of death or readmission for patients who underwent transfemoral TAVI with either balloon-expandable or self-expandable THV systems. However, there were important differences in their safety profiles.