Gender Differences in Cardiac Reverse Remodeling in Mechanically Unloaded Hearts

Objectives: The abnormal structure and function of cardiomyopathic hearts can be partially reversed in patients supported by a left ventricular assist device (LVAD) by cardiac remodeling. There are growing numbers of reports identifying sex-related differences in the development and prognosis of heart failure. We analyzed gender differences in cardiac reverse remodeling in mechanically unloaded hearts of patients with LVADs.

Methods: A total of 110 patients with end-stage heart failure underwent LVAD implantation with a HeartWare device in our institution between January 2010 and August 2017, 15.5% (n = 17) were female (mean follow-up: 18.95 ± 12.36 months). In 8 female and 47 male patients, functional 1-year follow-up data were obtained and retrospectively analyzed focusing on reverse remodeling.

Results: Mean age at implantation was 59.18 ± 13.56 for female (F), and 55.32 ± 12.27 for male (M) patients (p = 0.29). HF etiology was DCM in 47.3% (n = 52), and ICM in 46.4% (n = 51) without significant gender differences, myocarditis (4.5%, n = 5), and toxic cardiomyopathy (1.8%, n = 2) was only seen in male patients. Mean Intermacs profile was 2.81 ± 1.17 in F vs. 2.9 ± 1.18 in M (p = 0.78). Thirty-day and long-term mortality showed no significant differences in gender distribution (p = 0.44; p = 0.45), and there was no significant difference in Intermacs adverse events (p = 0.12). Three myocarditis patients could successfully undergo LVAD-explantation, 2 (11.8%) F vs. 11 (11.8%) M patients underwent heart transplantation during follow-up.

Functional data in the 1-year follow-up group showed proBNP improved 60.91% in F vs. 78.12% in M (p = 0.08). 6-min-walk test improved by 23.65% in F vs. 18.39% in M patients (p = 0.47). LVEDD improved by 13.17 vs. 18.17% (p = 0.31), respectively. TAPSE decreased by 27.57% in F and increased by 25.03% in M (p < 0.01). Basal, mid, and apical RVEDD improved by 10.6% (F) vs. 23.7% (M) (p = 0.026).

Conclusions: In our study group, we saw no gender differences regarding baseline characteristics. Mortality and Intermacs adverse events were comparable between sexes. Functional remodeling showed a tendency towards better recovery in male patients with significantly improved recovery of right heart function. Underlying mechanisms of differential right heart remodeling between sexes need to be studied in more detail.