COST EFFECTIVENESS OF VENTRICULAR TACHYCARDIA ABLATION VERSUS ESCALATION OF ANTIARRHYTHMIC DRUG THERAPY IN THE VANISH TRIAL

Abstract

For survivors of myocardial infarction with implantable cardioverter-defibrillator (ICD) shocks despite antiarrhythmic drugs, the VANISH trial demonstrated improved clinical outcomes with catheter ablation compared to additional pharmacotherapy. This analysis uses the data from the randomised controlled trial to assess the cost effectiveness of catheter ablation (n=132) versus escalated antiarrhythmic therapy (escalated drug therapy) (n=127). Healthcare resource use and quality of life data was collected in the trial, and used to determine the cost-effectiveness of catheter ablation. Published references were used to estimate costs (2015 CAN $). Analysis was stratified by amiodarone therapy at baseline. The analysis was over 3 years, with a 5% discount rate. Adjustment was made for censoring and baseline utilities. Overall, ablation resulted in greater quality adjusted life years (QALYs) than escalated drug therapy (1.63 vs 1.49; difference: 0.14, 95% CI -0.20 to 0.47) and a higher cost ($64,728 vs $60,937; difference $3,790, 95% CI - $17,848 to $23,105); with an incremental cost per QALY gained for ablation versus escalated drug therapy of $26,575. The higher costs in the ablation arm were primarily due to the initial costs of ablation which were partially offset by the costs of subsequent ablations and adverse outcomes in the escalated drug therapy arm. Amiodarone use at baseline significantly impacted cost-effectiveness. For those on amiodarone at baseline, ablation dominated escalated drug therapy, with greater QALYs (1.48 vs 1.26, difference: 0.22 (95% CI -0.16 to 0.62)) and lower costs ($67,307 vs $68,959, difference: -$1,652 (95% CI -$33,230 to $22,268)). For patients not on amiodarone at baseline, ablation resulted in similar QALYs (1.90 vs 1.90, difference: -0.00 (95% CI -0.62 to 0.60)) and higher costs ($59,883 vs $45,874, difference: $14 009 (95% CI -$9,948 to $43,412)). For the total trial population, ablation was cost effective compared with escalation of drug therapy. This result was manifest for the subgroup of patients who were receiving amiodarone at baseline but not for those not receiving amiodarone.