Microvolt T-wave alternans and the selective use of implantable cardioverter defibrillators for primary prevention: a cost-effectiveness study.
OBJECTIVE
Implantable cardioverter defibrillators (ICDs) are an effective but expensive treatment for the prevention of sudden cardiac deaths in patients with severe left-ventricular dysfunction. Recent studies suggest that microvolt T-wave alternans (MTWA) predicts mortality and severe arrhythmic events in this population. However, the impact of MTWA on ICD cost-effectiveness is unknown.


METHODS
A Markov decision-analysis model evaluated three treatment strategies for primary prevention in patients with severe left-ventricular dysfunction: (i) medical therapy for all; (ii) ICD therapy for all; and (iii) selective ICD therapy based on non-negative (positive or indeterminate) MTWA test results. Incremental cost-effectiveness ratios (ICER) were calculated from the perspective of a third party payer using a 10-year time horizon. Sensitivity analyses examined the robustness of the estimates.


RESULTS
A treatment strategy involving ICD therapy in all patients was associated with an ICER of $121,800/quality-adjusted life-year (QALY) compared with medical therapy, whereas a treatment strategy involving the selective use of ICDs based on MTWA test results was associated with an ICER of $108,900/QALY compared with medical therapy. Sensitivity analyses suggest that, under most scenarios, the selective use of ICDs based on MTWA results does not decrease the ICER to below $100,000/QALY.


CONCLUSIONS
MTWA only marginally improves the cost-effectiveness of ICDs for primary prevention in patients with severe left-ventricular dysfunction. There remains a need for improved means to effectively identify which patients will derive the greatest benefit from ICD implantation.
Filion
Kristian B
KB
Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, 1020 Pine Avenue West Montreal, Quebec H3A 1A2, Canada. kristian.filion@mail.mcgill.ca
Xie
Xuanqian
X
van der Avoort
Charlotte J
CJ
Dendukuri
Nandini
N
Brophy
James M
JM