• Interventional Techniques & Devices Clinical Trials
• Valvular Disease

For patients with inoperable severe aortic stenosis, the incremental cost per life-year gained (LYG) for transcatheter aortic valve replacement (TAVR) is in line with values for other cardiovascular (CV) technologies. Matthew R. Reynolds, MD, MSc, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA, presented these findings, which are based on a cost-effectiveness study of the PARTNER trial (Cohort B).

Data for Cohort B of the PARTNER trial showed that TAVR offers substantial clinical outcome benefits, compared with standard care, for patients who are unsuitable for surgical aortic valve replacement (AVR) [Leon MB et al. NEJM 2010]. The economic analysis was designed to compare the two treatment approaches with respect to short-term and long-term costs and lifetime cost-effectiveness.

This study included all 358 subjects in Cohort B. The primary endpoint was the lifetime incremental cost-effectiveness ratio (ICER), expressed as cost per LYG. The secondary endpoint was lifetime incremental cost per quality-adjusted life-year gained (QALY).

The mean initial cost of TAVR was $78,540, which represented the procedural costs, nonprocedural costs, and estimated physician fees. Within the 12-month period of the PARTNER trial, the total follow-up cost (excluding the initial cost) was significantly lower for TAVR ($29,352) than for standard therapy ($52,724)—a difference of $23,372 (p<0.001). The greater follow-up cost that was associated with standard therapy was related to a significantly higher hospitalization rate (2.15 vs 1.02; p<0.001). This higher rate was due entirely to admissions for CV causes. The greater hospitalization cost that was associated with standard therapy was offset slightly by higher costs for rehabilitation and skilled nursing facilities that are associated with TAVR (total 12-month cost difference, $23,372; p<0.001).

Using parametric survival models to extrapolate life expectancy beyond the observed follow-up period, the researchers estimated a 1.9-year-longer life expectancy for TAVR compared with standard care (3.1 vs 1.2 years). The lifetime incremental cost of TAVR was $79,837, with a lifetime incremental gain in life expectancy of 1.59 years (TAVR-control) after applying a standard economic discount rate of 3% per year to both future costs and benefits. The resultant incremental cost-effectiveness ratio was $50,212/LGY. Bootstrap resampling demonstrated that the probability of cost-effectiveness was 47% for a threshold of $50,000 per LYG and 95% for a threshold of $60,000/LYG.

When the effectiveness measure was changed from LYG to QALYs gained for the secondary analysis, the incremental benefit decreased slightly (1.29 QALYs).

The authors note that these results compare favorably with the costs of other currently used CV treatments, including implantable cardiac defibrillators and atrial fibrillation ablation, and cost less than hemodialysis, percutaneous coronary intervention for stable disease, and left ventricular assist devices.

The study has several limitations. Because the experience with TAVR is still early, care may become more efficient in the future. In addition, care of the control group in the trial may have differed from that for similar patients in community practice. There is also some uncertainty about the lifetime analysis in the study—particularly the cost projections beyond the trial period. Lastly, the patient population of Cohort B was old and at high risk, and the results can not be extrapolated to other patient groups.

Still to be determined is the cost-effectiveness of TAVR compared with surgical AVR, an important point, given the most recent PARTNER data that showed similar clinical outcomes for these two procedures.

• © 2011 MD Conference Express