The Utility of Eccentricity Index as a Measure of the Right Ventricular Function in a Lung Resection Cohort

Right ventricular (RV) dysfunction occurs after lung resection and is associated with postoperative morbidity. Noninvasive evaluation of the RV is challenging, particularly in the postoperative period. A reliable measure of RV function would have value in this population.

This study compares eccentricity index (EI) obtained by transthoracic echocardiography (TTE) with cardiovascular magnetic resonance (CMR) determined measures of RV function in a lung resection cohort. CMR is the reference method for noninvasive assessment of RV function.

Prospective observational cohort study at a single tertiary hospital.

Twenty-eight patients scheduled for elective lung resection underwent contemporaneous TTE and CMR imaging preoperatively, on postoperative day (POD) 2 and at 2-month. Systolic and diastolic EI was measured offline from anonymized and randomized TTE and CMR images.

Bland-Altman analysis was performed to determine agreement between EI^TTE and EI^CMR. Changes over time and comparison with CMR determined RV ejection fraction (RVEF^CMR) was assessed.

Bland-Altman analysis showed a negligible mean difference between EI^TTE and EI^CMR, but limits of agreement were wide (SD 0.24 and 0.28). There were no significant changes in EI^TTE and EI^CMR over time (P > 0.35). We found no association between EI^TTE with RVEF^CMR at all-time points (P > 0.22). Systolic and diastolic EI^CMR on POD 2 demonstrated moderate association with RVEF^CMR (r = -0.54 and r = -0.59, P ≤ 0.01). At 2-month, only diastolic EI^CMR correlated with RVEF^CMR (r = -0.43, P = 0.03). There were no meaningful associations between EI^TTE and EI^CMR with TTE-derived RV systolic pressure (P > 0.31).

TTE determined EI is not useful as a noninvasive method of assessing RV function following lung resection.