Impact of Left Ventricular Size on Outcomes Following HeartMate 3 Left Ventricular Assist Device Implantation: Analysis of the European Registry for Patients With Mechanical Circulatory Support (EUROMACS)

We investigated the association of preimplant left ventricular end-diastolic diameter (LVEDD) with outcomes after HeartMate 3 (HM3) left ventricular assist device (LVAD) implantation. Patients from the European Registry for Patients with Mechanical Circulatory Support (EUROMACS) registry who underwent HM3 implantation from August 2014 to February 2023 (n = 834) were analyzed according to preoperative LVEDD: less than or equal to 65 (n = 251), 65-80 (n = 441), and greater than or equal to 80 mm (n = 142). The mean age was 54.4 ± 12.4 years, body surface area (BSA) 2.0 ± 0.23 m 2 , body mass index (BMI) 27.3 ± 5.0 kg/m 2 ; 87.9% were male and 40% had ischemic cardiomyopathy. Patients with LVEDD less than or equal to 65 mm were older (56.1 ± 11.0 vs . 53.8 ± 13.0 vs . 53.0 ± 12.3 years; p = 0.015), more female (17.9% vs . 11.6% vs . 4.9%; p < 0.001), smaller BSA (1.95 ± 2.03 vs . 2.01 ± 0.22 vs . 2.08 ± 0.22 m 2 ; p < 0.01) and lower BMI (26.6 ± 4.8 vs . 27.4 ± 5.1 vs . 28.2 ± 5.0; p = 0.01) compared to LVEDD 65-80 and greater than or equal to 80 mm, respectively. One year survival was associated with increasing LVEDD (75.7% vs . 84.6% vs . 89.5%; p = 0.003). Patients with LVEDD less than or equal to 65 mm had a higher risk of postoperative right heart failure (14.7% vs .10.4% vs . 6.8%; p = 0.03), the risk for postoperative stroke was similar (10% vs . 12.8% vs . 9.5%; p = 0.4). A small left ventricular (LV) size (LVEDD ≤ 65 mm) was associated with an increase in postoperative right heart failure and unadjusted 1 year mortality in adults who underwent HM3 LVAD implantation.