Risk of Thrombus Formation in Patients on Mechanical Circulatory Support with POLVAD-MEV

BACKGROUND: Congestive heart failure is a challenging problem due to increasing prevalence in developed countries. Patients admitted due to decompensated congestive heart failure symptoms who do not respond to medical treatment require mechanical circulatory support. Patients with biventricular failure are at particularly high mortality risk.
MATERIAL AND METHODS: We analyzed the function of 49 pumps (POLVAD-MEV, FRK Intra-cordis, Poland) implanted to rescue INTERMACS 1 and 2 profile patients referred to our department due to severe congestive heart failure. All patients were waiting for heart transplantation and were readmitted due to acute decompensations of congestive biventricular heart failure with resistance to medical therapy.
RESULTS: During the observational period, there were no technical problems in pump function. The mean duration of pump therapy was 30.6±8.3 (5-49) days. The risk for right-sided pump complications included clots formation on the following parts of the pump: outflow tract (1, 2%), membrane (13, 27%), dome (6, 12.5%), and periphery (1, 2%). The overall risk for device thrombosis was 41%. The risk for thromboembolic complications was CRP-dependent regarding conglomerates of fibrin and platelets formation (p<0.05). The risk for left-sided pump complications included clots formation on the outflow tract (1, 2%), membrane (9, 19%) and dome (3, 6%). The overall risk for device thrombosis was 27%. The risk for clots formation on the membrane (P<0.05) and dome of the pump depended on time (P<0.07).
CONCLUSIONS: Mechanical circulatory support with a paracorporeal pump is a safe option for biventricular heart dysfunction as a bridge to heart transplantation. The risk for thrombi formation is relatively high but acceptable within 30 days after implantation.

Keywords: Advanced Cardiac Life Support, Embolism and Thrombosis, Heart Failure, Heart-Assist Devices, Pulsatile Flow