Incidence of Late Right Heart Failure Following Left Ventricular Assist Device Implantation and Impact of PDE5i Therapy on Long-term Clinical Outcomes

Background Late right heart failure (LRHF) following left ventricular assist device (LVAD) implantation is a vexing complication with high incidence rate and adverse impact on outcomes. Phosphodiesterase-5-inhibitor (PDE5i) therapy is often used in LVAD patients to ameliorate right ventricular afterload and prevent right heart failure. Aim To investigate the incidence of LRHF following LVAD implantation and study the impact of PDE5i use on patients’ outcomes. Methods We conducted a retrospective analysis of all patients who underwent implantation of HeartMate (HM) II or HM III devices as destination therapy at our center between May 2017 and August 2021. Primary endpoint was the cumulative incidence of hospitalizations related to LRHF at 12 months post-LVAD implantation. Secondary outcomes included incidence of LRHF hospitalizations at 1 month, 3, months, and 6 months post-LVAD implantation as well as other surrogate markers for LRHF, namely right atrial pressure ≥ 15 mmHg, moderate or greater severity tricuspid regurgitation, AST > 40 units/l, and serum creatinine > 2 mg/dl. Additionally, we collected data on PDE5i use and analyzed its impact on primary and secondary outcomes. Fischer's exact test and 2-tailed t-test were conducted for categorical and continuous variables respectively. Univariate and multivariate logistic regression was conducted for factors affecting the primary outcome. Results A total of 46 patients with LVAD implantation (sildenafil=26, control=20) were identified with mean age 59, male 72%, Black 77%, and BMI 30. Baseline characteristics including demographics, co-morbid conditions, cardiac medications, laboratory, and echocardiographic/Doppler data prior to LVAD implantation were equally distributed between the treatment and control groups. Primary outcome of LRHF at 12 months occurred in 8 (22%) patients. Secondary outcomes of LRHF at 1 month, 3 months, and 6 months occurred in 3 (6%), 5 (11%), and 6 (14%) patients respectively. After adjusting for age, gender, race, type of cardiomyopathy, and BMI, PDE5i use was associated with a nonsignificant increase in RHF hospitalizations at 12 months post-LVAD implantation (OR: 5.89 (0.43-80.11); P = 0.18). Nonischemic cardiomyopathy was an independent predictor for RHF hospitalization at 12 months (OR: 13.49 (1.03-176.37); P = 0.04). Overall incidence of secondary outcomes was similar between sildenafil and control groups at one, three, six, and twelve months after LVAD implantation. Conclusions Late right heart failure following LVAD implantation is common, and non-ischemic cardiomyopathy is a risk factor for its development. PDE5i therapy conferred no benefit in preventing LRHF hospitalizations. Late right heart failure (LRHF) following left ventricular assist device (LVAD) implantation is a vexing complication with high incidence rate and adverse impact on outcomes. Phosphodiesterase-5-inhibitor (PDE5i) therapy is often used in LVAD patients to ameliorate right ventricular afterload and prevent right heart failure. To investigate the incidence of LRHF following LVAD implantation and study the impact of PDE5i use on patients’ outcomes. We conducted a retrospective analysis of all patients who underwent implantation of HeartMate (HM) II or HM III devices as destination therapy at our center between May 2017 and August 2021. Primary endpoint was the cumulative incidence of hospitalizations related to LRHF at 12 months post-LVAD implantation. Secondary outcomes included incidence of LRHF hospitalizations at 1 month, 3, months, and 6 months post-LVAD implantation as well as other surrogate markers for LRHF, namely right atrial pressure ≥ 15 mmHg, moderate or greater severity tricuspid regurgitation, AST > 40 units/l, and serum creatinine > 2 mg/dl. Additionally, we collected data on PDE5i use and analyzed its impact on primary and secondary outcomes. Fischer's exact test and 2-tailed t-test were conducted for categorical and continuous variables respectively. Univariate and multivariate logistic regression was conducted for factors affecting the primary outcome. A total of 46 patients with LVAD implantation (sildenafil=26, control=20) were identified with mean age 59, male 72%, Black 77%, and BMI 30. Baseline characteristics including demographics, co-morbid conditions, cardiac medications, laboratory, and echocardiographic/Doppler data prior to LVAD implantation were equally distributed between the treatment and control groups. Primary outcome of LRHF at 12 months occurred in 8 (22%) patients. Secondary outcomes of LRHF at 1 month, 3 months, and 6 months occurred in 3 (6%), 5 (11%), and 6 (14%) patients respectively. After adjusting for age, gender, race, type of cardiomyopathy, and BMI, PDE5i use was associated with a nonsignificant increase in RHF hospitalizations at 12 months post-LVAD implantation (OR: 5.89 (0.43-80.11); P = 0.18). Nonischemic cardiomyopathy was an independent predictor for RHF hospitalization at 12 months (OR: 13.49 (1.03-176.37); P = 0.04). Overall incidence of secondary outcomes was similar between sildenafil and control groups at one, three, six, and twelve months after LVAD implantation. Late right heart failure following LVAD implantation is common, and non-ischemic cardiomyopathy is a risk factor for its development. PDE5i therapy conferred no benefit in preventing LRHF hospitalizations.