The Prognostic Role of Pulmonary Arterial Elastance in Patients Undergoing Left Ventricular Assist Device Implantation: A Pilot Study

<b>Background</b>: Pulmonary arterial elastance (Ea) is a helpful parameter to predict the risk of acute postoperative right ventricular failure (RVF) after left ventricular assist device (LVAD) implantation. A new method for calculating Ea, obtained by the ratio between transpulmonary gradient and stroke volume (Ea^B), has been proposed as a more accurate measure than the Ea obtained as the ratio between pulmonary artery systolic pressure and stroke volume (Ea^C). However, the role of Ea^B in predicting acute RVF post-LVAD implantation remains unclear. <b>Methods and Results</b>: A total of 35 patients who underwent LVAD implantation from 2018 to 2021 were reviewed in this retrospective analysis. Acute RVF after LVAD implantation occurred in 12 patients (34%): 5 patients with moderate RVF (14% of total) and 7 patients with severe RVF. The Ea^B was not significantly different between the "severe RVF" vs. "not-severe RVF" groups (0.27 ± 0.04 vs 0.23 ± 0.1, <i>p</i> < 0.403). However, the combination of arterial elastance and central venous pressure was significantly different between the "not-severe RVF" group (central venous pressure < 14 mmHg and Ea^C < 0.88 mmHg/mL or Ea^B < 0.24 mmHg/mL; <i>p</i> < 0.005) and the "severe RVF" group (central venous pressure > 14 mmHg and Ea^C > 0.88 mmHg/mL or Ea^B > 0.24 mmHg/mL; <i>p</i> < 0.005). <b>Conclusions</b>: Ea is a reliable parameter of right ventricular afterload and helps discriminate the risk of acute RVF after LVAD implantation. The combined analysis of Ea and central venous pressure can also risk stratify patients undergoing LVAD implantation for the development of RVF.