Assessing Left Ventricular Unloading and Wall Tension to Predict the Need for Durable Mechanical Circulatory Support after Peripheral VA-ECMO

Purpose Peripheral veno-arterial extracorporeal membrane oxygenation (pVA-ECMO) has gained increasing value in the management of advanced cardiogenic shock. Unloading the left ventricle (LV) while reducing myocardial oxygen consumption (MVO 2 ) are crucial for myocardial recovery during pVA-ECMO. To study the effects of a pulmonary capillary wedge pressure (PCWP)-directed protocol in patients on pVA-ECMO (goal: PCWP Methods Following IRB approval, we identified 99 patients with advanced cardiogenic shock undergoing pVA-ECMO and at least one formal transthoracic echocardiography study (TTE) during pVA-ECMO. We analyzed demographic data, routine laboratory data, hemodynamic parameters, and TTE results. We used PCWP measurements and calculations of LV systolic wall tension (LV SWT ) to assess LV unloading and MVO 2 during pVA-ECMO, respectively. Statistical analyses included Mann-Whitney-U test and logistic regression modeling. Data are given as median (interquartile range). Results Survival to hospital discharge was 60.6%. 27.3% of all patients required transition to dMCS to be weaned off pVA-ECMO. 10.1% of all patients developed refractory LV distention with pulmonary edema despite maximum medical treatment and required either atrial septostomy or additional mechanical support. Minimum PCWP readings during pVA-ECMO were 12.8 mmHg (11.0-14.4) in patients without and 10.0 mmHg (8.0-17.0) in patients with need for dMCS (p=0.236). Minimum LV SWT during pVA-ECMO were 2.7 × 10 5 dynes/cm (2.0-3.5) in patients without and 3.5 × 10 5 dynes/cm (3.1-4.0) in patients with need for dMCS (p=0.002). Adjusting for age and race in a logistic regression model revealed that only post-cardiotomy pVA-ECMO and LV SWT , but not minimum PCWP were independently associated with need for dMCS after pVA-ECMO. Conclusion We show that strict medical management can lead to LV unloading, i.e. minimum PCWP SWT during pVA-ECMO remained predictive of need for dMCS even with unloaded LV.