Prognostic Implication of RV Coupling to Pulmonary Circulation for Successful Weaning From Extracorporeal Membrane Oxygenation.

Objectives: The aim of this study was to explore if right ventricular (RV) contractile function and its coupling to pulmonary circulation (PC) were associated with successful weaning from venoarterial-extracorporeal membrane oxygenation (VA-ECMO) at maintenance of pump flow.

Background: Limited data are available on predictors of successful weaning from VA-ECMO.

Methods: A total of 79 patients with cardiogenic shock underwent transthoracic echocardiography to evaluate weaning from ECMO and were prospectively enrolled between 2016 and 2019. The noninvasively measured RV-PC coupling index was acquired by indexing tricuspid annular S' velocity, tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and RV free-wall longitudinal strain (FWLS) to right ventricular systolic pressure (RVSP).

Results: Transthoracic echocardiography was performed at a median 3.0 days (range 1 to 6 days) after ECMO initiation at a median ECMO flow of 3.2 l/min (range 3.0 to 3.6 l/min). The RV-PC coupling matrix, tricuspid annular S'/RVSP, TAPSE/RVSP, and RV FWLS/RVSP exhibited satisfactory predictive performances for predicting successful weaning from ECMO. Using the best cutoff values derived from the area under the receiver-operator characteristic curve, tricuspid annular S'/RVSP demonstrated a significantly better predictive performance than conventional echocardiographic parameters (left ventricular ejection fraction >20%, left ventricular outflow tract time-velocity integral ≥10 cm, and mitral annular S' ≥6 cm/s).

Conclusions: Echocardiographic RV-PC coupling metrics exhibited a significantly better performance for predicting successful weaning from VA ECMO compared with conventional echocardiographic criteria at maintenance of pump flow.