Transcatheter aortic valve replacement (TAVR) provides substantial benefits over standard therapy for health-related quality of life in patients with severe aortic stenosis who were not suitable for cardiac surgery, according to research published in the Oct. 4 issue of Circulation.
In a substudy of the PARTNER (Placement of Aortic Transcatheter Valves) trial, first presented AHA 2010, Matthew R. Reynolds, MD, of the Saint Luke’s Mid America Heart and Vascular Institute in Kansas City, and colleagues studied the quality of life of patients who underwent TAVR. They noted that while PARTNER showed a reduction in all-cause mortality for this patient group, it also found an increase in the incidence of stroke and vascular complications and did not address quality of life.
“Given the advanced age and poor general health of the patients enrolled in the PARTNER trial, it is important to establish how TAVR, a relatively new procedure with distinct risks and limitations, affects health status compared with the best alternative therapy,” Reynolds and colleagues wrote.
The substudy included 358 patients enrolled in PARTNER who had severe symptomatic aortic stenosis and who were not candidates for surgery. The patients were evenly split into a TAVR group and a standard therapy group. The researchers administered the Kansas City Cardiomyopathy Questionnaire (KCCQ) four times (at baseline, one month, six months and 12 months) to determine disease-specific health status, which includes quality-of-life questions. General health status was determined through the Medical Outcomes Study Short Form 12 (SF-12).
Previous studies have shown that the KCCQ scores are roughly parallel with New York Heart Association functional class rankings, with a score between 75 and 100 equal to Class I, 60 to 74 Class II, 45 to 59 Class III and 0 to 44 Class IV. The authors added that in heart failure patients, KCCQ has been shown to independently predict mortality and healthcare costs.
Baseline scores for both groups were low and improved over time. But gains among the TAVR group were greater than among the standard therapy group. At one month, the mean difference between the TAVR and standard therapy group was 13 points; at six months, 21 points; and at 12 months, 26 points. The TAVR group also had higher SF-12 physical and mental health scores, at 5.7 and 6.4 points respectively.
“In our study, the mean between-group differences in the KCCQ summary score six and 12 months after enrollment met or exceeded the 20-point threshold considered to signify a very large improvement in heart failure status, and more than 75 percent of surviving patients had at least a large (10-point) improvement over baseline,” Reynolds et al wrote. “Moreover, the proportion of patients who achieved an excellent outcome at 12 months (defined as surviving with at least a 20-point improvement in the KCCQ summary score) was far greater with TAVR than with standard care.”
The authors listed several study limitations, including a decrease in the number of study participants over time due to deaths; potential biases introduced by missing data; and the fact that PARTNER was not a blind trial, which might have led to a placebo effect.
Overall, they concluded, their results indicated that after one year TAVR offered meaningful improvements in the quality of life and health status for patients despite comorbidities and age.