Technical and Mechanical Problems and Failures of HeartMate II versus HeartMate 3: The Rotterdam Experience

Abstract

<h3>Purpose</h3> Long-term durability and incidence of potential mechanical device failure (MDF) is a known issue in medical devices. In this study, we investigated the incidence of MDF in continuous flow left ventricular assist device (CF-LVAD) patients comparing Heartmate II versus Heartmate 3. <h3>Methods</h3> We conducted a retrospective study of all CF-LVADs (type HeartMate II en 3) implanted in our center. MDF was defined as a failure of driveline, inflow-outflow graft, electrical power, drive unit, or motor failure, excluding device failure because of a biologic complication (<i>e.g.</i>, device thrombosis, hemolysis, or infections). <h3>Results</h3> A total of 70 CF-LVADs Heartmate II were implanted in 63 patients (median support time 21.4 months [interquartile range (IQR), 8.7 to 34.4 months], mean age 49.6 ± 12.3 years, 73% male) and 101 Heartmate 3 devices were implanted in 101 patients. (median support time 24 months [IQR: 6.6 to 39.8 months], mean age 56.5 ± 10.3 years, 77% male). During follow up in total 24 MDFs occurred in 23 patients (24% in HMII and 8% in HM 3 patients). (log-rank = 0.03) (Figure 1). The main reason for MDF in the Heartmate II was a damaged or fractured driveline (n=8, 42% of MDF's). In 2 patients, sudden death was in all probability related to MDF. The main reason for MDF in the Heartmate 3 was an occluded outflow graft (n=3, 38%). In both Heartmate II and Heartmate 3, a common MDF reason were patients unnecessarily exchanging their system controller at home (n=3, 16%, resp n=2, 25%). Technical problems not resulting in MDF were common in both HM II (n=35, 56% of patients) and Heartmate 3 (n=46, 46%). <h3>Conclusion</h3> Various technical problems are common in patients with ongoing HeartMate II and 3 LVAD support, but mechanical failure occurred significantly less in patients with HeartMate 3. Periodical assessment of the technical integrity of the device remains of uttermost importance during long-term LVAD.