Background: Left ventricular (LV) eccentricity index (EI) is a measure of the LV shape obtained with a commonly used quantitative software for myocardial perfusion scintigraphy (MPS). However, there are limited studies evaluating its correlation with other MPS parameters, for which this study was done.
Method: All patients who underwent 99mTc-sestamibi stress MPS from 2013 to 2015 were screened. A total of 353 patients, 228 (65%) males and 125 (35%) females, met the inclusion criteria. One hundred twenty-nine (37%) underwent exercise stress while 224 (63%) was given dipyridamole. Spearman's rho correlation was used to determine the correlation of rest and post-stress EI with the other study variables.
Results: Among males, rest EI showed negative correlation with summed stress score (SSS) (rS = -0.182, p = <0.005), transient ischemic dilatation (TID) (rS = -0.172, p = 0.009), rest LV end-diastolic volume (EDV) (rS = -0.291, p = <0.001), rest LV end- systolic volume (ESV) (rS = -0.316, p = <0.001), post-stress LVEDV (rS = -0.278, p = <0.001), and post-stress LVESV (rS = -0.331, p = <0.001). There was positive correlation with rest LV ejection fraction (EF) (rS = 0.297, p = <0.001) and post-stress LVEF (rS = 0.336, p = <0.001). No significant relationship with any of the MPS parameters was observed among females. For both exercise and dipyridamole groups, EI exhibited negative correlation with SSS, and rest and stress LVESV; and positive correlation with rest and post-stress LVEF. Significant relationship with rest and stress LVEDV was only observed in the dipyridamole group.
Conclusion: This study shows that EI is correlated with most, if not all, of the MPS parameters with different levels of association depending on the patient's sex and the type of stress employed. More spherical LV is correlated with more severe perfusion defects, larger