P1651Pulmonary artery pressure could predict closed aortic valve in patients managed by veno-arterial extracorporeal membrane oxygenation

Abstract

Abstract Background Although veno-arterial extracorporeal oxygenation (VA-ECMO) is widely used as mechanical circulatory support, it reduces native left ventricular (LV) stroke volume through the cardiac preload decrease and afterload increase. Therefore some patients with severe cardiac dysfunction present persistently closed aortic valve (AV). The closed AV is considered to increase the risk of pulmonary edema or intracardiac thrombosis. However, little is known about the variables that contribute to persistently closed AV under the management of VA-ECMO. Purpose We investigated the factors that could predict persistently closed AV at the time of VA-ECMO initiation. Methods This was a retrospective chart review. We investigated the patients who received the management of VA-ECMO due to cardiogenic shock from April 2011 to December 2018, and analyzed 18 patients (43±16 years, 50% female) who presented closed AV immediately after the introduction of VA-ECMO. We obtained the hemodynamic data at the time of VA-ECMO initiation (baseline) and 24h after. The patients who presented persistently closed AV during 24h were defined as Close-group (n=8). The patients whose AV was opened within 24h were defined as Open-group (n=10). The status of AV was investigated by the echocardiogram. Results All patients were managed by concomitant use of intra-aortic balloon pumping. The etiologies were myocarditis (56%), cardiomyopathy (33%), and acute myocardial infarction (11%). Nine patients experienced in-hospital death (6 were Close-group and 3 were Open-group, p=0.15). At baseline, there were no significant differences between mean arterial blood pressure (mABP) (p=0.07), central venous pressure (CVP) (p=0.71), and left ventricular ejection fraction (p=0.44). However, Close-group had significantly lower mean pulmonary artery pressure (MPAP) and pulmonary artery pulse pressure (PAPP) than Open-group (Close-group versus Open-group; MPAP, 15±6 mmHg versus 27±11 mmHg, p=0.01; PAPP, 3±2 mmHg versus 8±3 mmHg, p=0.01). Logistic regression analyses revealed the lower MPAP and PAPP had the predictive value of closed AV within 24-h after VA-ECMO initiation [MPAP: odds ratio (OR) 0.78, 95% confidence interval (95% CI) 0.62–0.99, P=0.003; PAPP: OR 0.18, 95% CI 0.02–1.13, P<0.001]. In the following 24h, no significant change was found in MPAP and PAPP. Conclusion At the time of VA-ECMO initiation, lower MPAP and PAPP had the predictive value for persistently closed AV. LV preload derived from right heart function would have major impact on AV status.