Apical systolic eccentricity index: a better marker of right ventricular compromise in pulmonary hypertension

Systolic eccentricity index (sEI) has been traditionally measured at the papillary muscle (PM) level. However, this measurement does not take into account the remodeling that occurs in the right ventricle (RV) during chronic pulmonary hypertension (cPH).

Standard echocardiographic data were collected on 50 patients (age 58 + or - 14 years) with known cPH (74 + or - 22 mmHg; range 45-120 mmHg) who had adequate short-axis views at the mitral valve (MV), PM, and apical (AP) levels to measure sEI. All had a normal left ventricular ejection fraction (72 + or - 10%).

In a multivariate analysis, the traditional PM level sEI correlated the best with cPH when pulmonary artery systolic pressures (PASP) ranged between 45 and 60 mmHg (r =-0.569, P < 0.001) while AP level sEI was better when all patients were included in the analysis (r =-0.843, P < 0.0001). Not only was AP level sEI the only echo variable helpful in identifying a dilated end diastolic RV area (r =-0.730, P < 0.0001) but also patients with worse RV systolic performance (r = 0.686, P < 0.0001). MV level sEI was not better than PM level sEI.

AP level sEI appears to be superior to traditional PM level sEI measurement as it correlates better with worsening PH severity, RV cavity dilation and RV systolic dysfunction. Further studies are now required to prospectively study how these septal abnormalities in cPH may affect RV as well as LV systolic and diastolic function. (Echocardiography 2010;27:534-538).