DENVER—Compared to warfarin, the percutaneous left atrial appendage occlusion (PLAAO) device strategy, such as with Watchman (Atritech), results in comparable quality-adjusted life expectancy and is cost effective across a "broad range of model assumptions," researchers from Stanford University reported at the 31st annual Heart 31st annual Heart Rhythm Society scientific sessions.
According to lead author Mintu Turakhia, MD, director of cardiac electrophysiology at Palo Alto VA Health Care System and instructor of medicine at Stanford University School of Medicine in Palo Alto, Calif., warfarin (Coumadin, Bristol Myers-Squibb) reduces the risk of stroke but requires frequent laboratory monitoring, and under- or over-anticoagulation may lead to increased morbidity, death and cost.
“PLAAO with a device can obviate the need for anticoagulation, and the recent PROTECT AF trial showed non-inferiority to warfarin for stroke outcomes,” Turakhia said. “The up-front adverse events and cost of PLAAO may be offset by the long-term benefits of discontinuing anticoagulation.”
Therefore, the researchers compared the quality-adjusted survival and cost of warfarin and PLAAO in patients with nonvalvular AF.
Using a Markov model, they performed a decision analysis comparing PLAAO and adjusted-dose warfarin in a hypothetical cohort of 65 year-old patients with AF at moderate- to high-risk of stroke and no contraindications to anticoagulant therapy with a maximum time horizon of 35 years. The investigators based their model inputs (event rates, utilities, costs) on previous warfarin studies, the PROTECT-AF trial, and Medicare reimbursement schedule, discounted at 3 percent per annum and expressed in 2009 U.S. dollars.
Also, they modeled the PROTECT-AF protocol to capture costs and utilities of full peri-procedural care and also modeled a warfarin-continuation strategy in a proportion of PLAAO patients in whom occlusion did not successfully exclude the LAA from systemic circulation.
Turakhia reported that quality-adjusted life expectancy was 11.33 years with warfarin and 11.49 years with PLAAO.
The researchers also found that the total lifetime costs were $135,800 for warfarin and $137,600 for PLAAO. The incremental cost-effectiveness ratio of PLAAO over warfarin was $11,200 per quality-adjusted life years (QALY).
Turakhia concluded that their “analysis of PLAAO cost effectiveness compared with warfarin was sensitive to the risk of device endothelization failure (warfarin continuation), procedure cost and intracranial hemorrhage risk with warfarin. However, PLAAO costs less than $50,000 per QALY over a broad range of model assumptions.”