E/E' and D-shaped Left Ventricle Severity in Patients with Increased Pulmonary Artery Pressure

BACKGROUND: D-shaped left ventricle (D-LV) is an interesting echocardiographic finding in pulmonary hypertension (PH) and is the result of structural distortion of the interventricular septum. The eccentricity index (EI) is a quantitative measure used to evaluate the severity of D-LV in patients with increased pulmonary artery pressure (PAP). However, D-LV and EIs have rarely been studied in terms of their association with hemodynamic factors. METHODS: A total of 526 patients with a maximal tricuspid regurgitation velocity (VmaxTR) > 2.8 m/s on echocardiography identified between January 2012 and December 2017 were enrolled. After exclusion, a total of 289 patients were analyzed. The association between D-LV and hemodynamic factors were analyzed using logistic regression. Furthermore, factors that impacted the severity of the D-LV, as defined by EIs, were also analyzed using the multiple linear regression model. RESULTS: In the multivariate logistic regression model, higher pulmonary artery pressure (PAP, p = 0.001), lower tricuspid annular plane systolic excursion (TAPSE, p = 0.048), and E/E′ (p = 0.017) were found to be significant risk factors for the presence of D-LV. Additional analysis with age and body mass index added to independent variables, PAP (p = 0.008), TAPSE (p = 0.028), and age (p < 0.001) were significant risk factors for the presence of D-LV. In patients with D-LV, only E/E' was independently associated with EIs ($R^2=0.666$, p < 0.001). CONCLUSIONS: In patients with increased PAP, D-LV is associated with PAP, TAPSE, E/E', and age. EIs are associated with left ventricular filling pressure, represented as E/E'.