Health status after transcatheter aortic valve replacement in patients at extreme surgical risk: results from the CoreValve U.S. trial

Abstract

Objectives: The purpose of this study was to characterize health status outcomes after transcatheter aortic valve replacement (TAVR) with a self-expanding bioprosthesis among patients at extreme surgical risk and to identify pre-procedural patient characteristics associated with a poor outcome.

Background: For many patients considering TAVR, improvement in quality of life may be of even greater importance than prolonged survival.

Methods: Patients with severe, symptomatic aortic stenosis who were considered to be at prohibitive risk for surgical aortic valve replacement were enrolled in the single-arm CoreValve U.S. Extreme Risk Study. Health status was assessed at baseline and at 1, 6, and 12 months after TAVR using the Kansas City Cardiomyopathy Questionnaire (KCCQ), the Short Form-12, and the EuroQol-5D. The overall summary scale of the KCCQ (range 0 to 100; higher scores = better health) was the primary health status outcome. A poor outcome after TAVR was defined as death, a KCCQ overall summary score (OS) <45, or a decline in KCCQ-OS of 10 points at 6-month follow-up.

Results: A total of 471 patients underwent TAVR via the transfemoral approach, of whom 436 (93%) completed the baseline health status survey. All health status measures demonstrated considerable impairment at baseline. After TAVR, there was substantial improvement in both disease-specific and generic health status measures, with an increase in the KCCQ-OS of 23.9 points (95% confidence interval [CI]: 20.3 to 27.5 points) at 1 month, 27.4 points (95% CI: 24.2 to 30.6 points) at 6 months, 27.4 points (95% CI: 24.1 to 30.8 points) at 12 months, along with substantial increases in Short Form-12 scores and EuroQol-5D utilities (all p < 0.003 compared with baseline). Nonetheless, 39% of patients had a poor outcome after TAVR. Baseline factors independently associated with poor outcome included wheelchair dependency, lower mean aortic valve gradient, prior coronary artery bypass grafting, oxygen dependency, very high predicted mortality with surgical aortic valve replacement, and low serum albumin.

Conclusions: Among patients with severe aortic stenosis, TAVR with a self-expanding bioprosthesis resulted in substantial improvements in both disease-specific and generic health-related quality of life, but there remained a large minority of patients who died or had very poor quality of life despite TAVR. Predictive models based on a combination of clinical factors as well as disability and frailty may provide insight into the optimal patient population for whom TAVR is beneficial. (Safety and Efficacy Study of the Medtronic CoreValve® System in the Treatment of Symptomatic Severe Aortic Stenosis in High Risk and Very High Risk Subjects Who Need Aortic Valve Replacement; NCT01240902).

Keywords: aortic stenosis; heart valves; quality of life; transcatheter aortic valve replacement.

Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1. Patient Flow Chart

Consort diagram showing patient flow for the CoreValve U.S. Pivotal trial. The black box indicates the primary analytic population for this quality of life study.

Figure 2. Disease-specific Health Status after TAVR

Changes in disease-specific health status according to the KCCQ overall summary scale (panel A) and subscales (panels B-E) at 1, 6, and 12 months after TAVR. Baseline values indicated by the dashed line correspond to the evaluable patient population at each time point. Mean values and p-values are derived from paired t-tests comparing each patient with his or her own baseline value.

Figure 3. Generic Health Status After TAVR

Changes in generic health status according to the SF-12 and EQ-5D at 1, 6, and 12 months after TAVR. Baseline values indicated by the dashed line correspond to the evaluable patient population at each time point. Mean values and p-values are derived from paired t-tests comparing each patient with his or her own baseline value.