Candidate for the Lee B. Lusted Student Prize Competition
Purpose: Aortic stenosis, the most common valvular disease in the elderly, is associated with high morbidity and mortality. Surgical aortic valve replacement is the only treatment option available that prolongs life. Transcatheter aortic valve implantation (TAVI) is a new technology that appears to offer dramatic improvements in the quality and quantity of life of patients with aortic stenosis not eligible for surgical valve replacement. Using the results of the multicenter, randomized control PARTNER trial, we sought to determine if TAVI is cost effective compared with medical management.
Method: We developed a decision analytic Markov model to follow cohorts of 83 year old patients with severe aortic stenosis who also shared the other baseline characteristic seen in the PARTNER RCT: >92% had New York Heart Association (NYHA) class III or IV symptoms, and all had Society of Thoracic Surgeons risk score of 10% or higher. As in the trial, TAVI reduced mortality by 23% over two years. Model costs came from Medicare and the Nationwide Inpatient Sample (2008 US$). We compared the strategies of TAVI and medical management, which included the option of balloon aortic valvuloplasty.
Result: TAVI was the most effective, but also the most expensive, treatment option providing an expected 1.98 QALYs at an average cost of $99,700 per person. In contrast, medical management resulted in 1.25 QALYs at an average cost of $63,200. Compared to medical management, TAVI cost $49,500 per QALY gained. This result was sensitive to annual health care costs in surviving patients. With a willingness to pay threshold of $100,000/QALY, TAVI was the optimal policy if health care costs other than those due to aortic stenosis were <$54,000/year. Clinically appropriate variation in other parameters, like procedural effectiveness, ongoing rates of death, and use of valvuloplasty in the medical treatment arm, had only modest effects on estimated cost-effectiveness. Furthermore, TAVI resulted in 56% of the cohort’s remaining life being spent with NYHA class I or II symptoms, instead of class III or IV symptoms. Depending on the extent of valvuloplasty use, the cohort receiving medical management was asymptomatic 0 to only 45% of the time.
Conclusion: TAVI appears to be a cost-effective treatment for patients with symptomatic aortic stenosis who are not candidates for surgery.