Hemocompatibility-Related Adverse Events Associated With or Without Low Molecular Weight Heparin Bridging in Outpatients With a HeartMate 3 Left Ventricular Assist Device.

BACKGROUND

Prior studies of anticoagulation bridging during periods of low International Normalized Ratio (INR) in outpatients with a durable, continuous flow left ventricular assist device (CF-LVAD) have shown a variable impact on thrombotic and bleeding events. These studies include predominantly older devices such as the HeartMate 2 (HM2) and HeartWare HVAD, which are known to experience more overall thrombotic events than the HeartMate 3 (HM3) device. The majority of these patients also received concomitant aspirin.

METHODS

The primary objective of this study was to compare hemocompatibility-related adverse events (HRAEs) occurring while bridging subtherapeutic (≤ 1.7) INRs with therapeutic low-molecular weight heparin (LMWH) versus not bridging in outpatients with an HM3 CF-LVAD, many of whom were not receiving concomitant aspirin.

RESULTS

Of the 79 patients eligible for inclusion in this study, 64 were not bridged and 15 were bridged at least once during the study period. In the non-bridged group, there were a total of 12 HRAEs of 997 bridging opportunities (BOs) (1.20%) versus 0 of 39 BOs in the bridged group. Of the 12 HRAEs in the non-bridged group, 10 were bleeding events; the 2 thrombotic events were minor venous thromboembolisms.

CONCLUSION

Omission of LMWH bridging in HM3 CF-LVAD patients with a subtherapeutic INR and low rates of background aspirin use did not result in a statistically significant or clinically relevant increase in the rate of HRAEs.