Markers of Right Ventricle Dysfunction Predict Exercise Capacity on Left Ventricular Assist Device (LVAD) Patients

Purpose Although Left Ventricular Assist Device (LVAD) improves functional capacity, on average LVAD patients are unable to achieve the aerobic capacity of normal healthy subjects or mild heart failure patients. The aim of this study was to examine if markers of right ventricular (RV) function influence maximal exercise capacity. Methods This was a single-centre prospective study that enrolled 20 consecutive HeartWare ventricular assist device (HVAD) patients who were admitted at the Freeman Hospital (Newcastle upon Tyne, United Kingdom) for a heart transplant assessment from August 2017 to October 2018. Results Mean peak oxygen consumption (Peak VO2) was 14.0 ± 5.0 ml/kg/min, and mean peak age and gender-adjusted percent predicted oxygen consumption (%VO2) was 40.0 ± 11.5 %. Patients were subdivided into 2 groups based on the median peak VO2, so each group consisted of 10 patients (50%). Right-sided and pulmonary pressures were consistently higher in the group with poorer exercise tolerance. Patients with poor exercise tolerance (peak VO2 below the median) had higher right atrial pressures at rest (10.6mmHg ± 6.4 versus 4.3mmHg ± 3.2, p= 0.02) and the increase with passive leg raising was significantly greater than those with preserved exercise tolerance (peak VO2 above the median). Patients with poor functional capacity also had greater RV dimensions (4.4 cm ± 0.5 versus 3.7 cm ± 0.5, p= 0.02) and a higher incidence of significant tricuspid regurgitation (TR) (moderate or severe TR in 5 patients in the poor exercise capacity group versus none in the preserved exercise capacity group, p=0.03). Conclusion Echocardiographic and hemodynamic markers of RV dysfunction discriminate between preserved and non-preserved exercise capacity in HVAD patients.