Pump thrombosis is a dreaded complication of left ventricular assist devices (LVADs). We completed a systematic review to evaluate the efficacy and complications associated with medical management of LVAD thrombosis. Databases were searched using the terms "vad*" or "ventricular assist device" or "heart assist device" and "thrombus" or "thrombosis" or "thromboembolism." Of 2,383 manuscripts, 49 articles met the inclusion criteria. The risk of partial or no resolution of LVAD thrombosis did not significantly differ between thrombolytic and nonthrombolytic regimens (odds ratio [OR], 0.48; 95% confidence interval [CI], 0.20-1.16). When response to therapy was evaluated based on pump type, there were no significant differences in how patients with a HeartMate II or HeartWare ventricular assist device responded to thrombolytic or nonthrombolytic treatment. Pooled risk of major bleeding in the thrombolytic group was 29% (95% CI, 0.17-0.44) and 12% (95% CI, 0.01-0.57) in the nonthrombolytic group. Odds of death did not differ between thrombolytic and nonthrombolytic regimens (OR, 1.28; 95% CI, 0.42-3.89). Although thrombolytic and nonthrombolytic treatment similarly resolved LVAD thrombosis, major hemorrhage may be increased with the use of thrombolysis. Randomized clinical trials comparing thrombolytic and nonthrombolytic treatment of LVAD thrombosis are needed to establish the most effective and safe option for patients who are not surgical candidates.