HAS-BLED and CHA2DS2-VASc Scores as Predictors of Bleeding and Thrombotic Risk after HeartMate II Ventricular Assist Device Implantation

Abstract

Purpose Bleeding and thromboembolic (TE) events are feared complications following continuous-flow ventricular assist device (CF-VAD) implant. Risk stratification may guide individualization of care and improve outcomes. The HAS-BLED scoring system has been shown to predict bleeding events in patients on chronic anticoagulation, while the CHA2DS2-VASc score has been shown to quantify stroke risk in patients with atrial fibrillation. We hypothesized that these widely used scores would be predictive of bleeding and TE complications after CF-VADs. Methods and Materials HAS-BLED and CHA2DS2-VASc scores were determined retrospectively for 171 consecutive patients who received HeartMate II (HMII) CF-VAD at a single center between 6/20/05 and 9/15/11. We excluded events occurring within 1 week and deaths occurring within 30 days of implant. Bleeding was defined as any systemic bleeding that required hospital admission or blood transfusion. TE events included ischemic stroke, transient ischemic attack, systemic emboli, or pump thrombosis. Results We observed 28 bleeding (16.3%) and 13 TE (7.6%) events in follow-up. The mean (±SD) HAS-BLED score was 2.1±1.0 vs 1.6±0.7 (p=0.01) in patients with bleeding versus those without, respectively. The mean (±SD) CHA2DS2-VASc scores were 3.4±1.2 vs 2.6±1.2 (p=0.03) in patients with TE events versus those without, respectively. HAS-BLED score ≥ 3 had a significantly higher risk for bleeding events compared to a score Conclusions A HAS-BLED or CHA2DS2-VASc score of 3 or more conferred significantly higher risks of bleeding or TE, respectively, following HMII implant. These scores may help clinicians construct individualized anticoagulation regimens for this high-risk group. [ Figure 1 ][ Figure 2 ]