Impact of Left Ventricular Assist Device on physical capacity in patients with end-stage heart failure

Résumé 0

Background The use of left ventricular assist devices (LVAD) widely increased in the past decade due to the lack of donor organs and the rising prevalence of heart failure. This therapy should lead patients in good condition to heart transplantation (bridge to transplant) or improve their quality of life (destination therapy). LVAD support is nowadays considered as an alternative to heart transplantation, however improvement in exercise performance is inconsistently demonstrated. The current study sought to quantitate physical capacity prior and subsequent LVAD implantation in order to assess the impact of this therapy. Methods and Results This study is a quantitative, observational, prospective, mono-centric trial which aimed to assess exercise capacity and its changes prior and subsequent LVAD implantation, using cardiopulmonary exercise testing (CPET), in patients suffering from refractory end-stage heart failure undergoing LVAD therapy with HeartMate 3 between 2017 and 2018 at the cardiac surgery department at CHUV. 21 patients underwent LVAD therapy during the study period, yet only 5 were included. CPET were completed an average of 11 months following implantation. Although VO2 max improved by approximately 30% subsequent LVAD implantation, from 9,60 ± 3,88 ml/kg/min to 12,46 ± 3,16 (t-test=-2,424; ddl=4; p=0,072), it was not statistically significant and remained considerably lower than predicted values. Nonetheless, improvement by at least one NYHA class was seen in 100% of patients, with 80% improving by two classes. As a result of the limited study sample size, firm reliance lacks between patients related clinical parameters and the variability in improvement of peak VO2. Conclusion Whereas VO2 max improves on LVAD support, but not significantly, it provides an adequate functional capacity suitable for daily living activities. Yet, the link between peak VO2, everyday tasks and quality of life requires further investigations in LVAD patients. Further studies should focus towards identifying predictive factors associated with lack of improvement in VO2 max and exertional capabilities in order to proceed with LVAD treatment concordant with patients’ values, objectives and expectations.