Abstract 90: Long-Term Impact of Mechanical Thrombectomy Randomized Trials in a Comprehensive Stroke Center: Individual Ethical Dilemmas versus Societal Benefits

Abstract

Introduction: Despite being the best sources of evidence for clinical interventions, randomized controlled trials (RCTs) may raise individual ethical concerns as often times control groups are left without treatments that might be perceived as beneficial. This becomes particularly challenging when centers must randomize patients to non-treatment versus modalities that were previously considered their standard of care. We aim to assess the overall societal costs and benefits related to two recent thrombectomy RCTs. Methods: Retrospective comprehensive stroke center database analysis. The number of MT was analyzed in the year prior and the year after the SWIFT-PRIME (all cases) and DAWN (6-24h cases) trials. The societal benefit was estimated based on (1) the number of control patients in the trials, (2) the number-need-to-treat (NNT) to achieve one additional good outcome (90-day mRS 0-2), and (3) the MT growth post trial completion. Results: SWIFT PRIME was presented in February 2015. The number of MT increased from 149 the year prior to 258 in the subsequent year (12.4±3.5 vs 21.42±5.48 patients/month, p=<0.001). Our site enrolled 12 patients including six controls. The NNT was 4. Thus, the net result was that we missed the opportunity to provide an uncertain benefit to 1.5 individuals in order to offer a definite benefit to an additional 109 patients and definitely benefit 27 of them. DAWN was presented in May 2017. The number of 6-24-h MT increased from 91 the year prior to 134 in the subsequent year (7.7±3.4 vs. 11.2±3.5 patients/month, p=0.02). Our site enrolled 38 patients including 16 controls. The NNT was 3. Thus, the net result was that we missed the opportunity to provide an uncertain benefit to 5.3 individuals in order to offer a definite benefit to an additional 43 patients and definitely benefit 14.3 of them. Conclusion: A considerable benefit from thrombectomy RCTs could be measured at our center despite pre-existent aggressive treatment protocols and outreach programs confirming that individual ethical concerns should be nullified in face of equipoise. The overall societal benefit after a scientific breakthrough vastly surpasses the alleged burden of those relative few control cases.