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

CONTEXT: 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. AIMS: 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. DESIGN AND SETTING: Prospective observational cohort study at a single tertiary hospital. MATERIALS AND METHODS: 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. STATISTICAL ANALYSIS: 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. RESULTS: 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). CONCLUSIONS: TTE determined EI is not useful as a noninvasive method of assessing RV function following lung resection.