Impact of Obesity on Left Ventricular Diastolic Parameters Derived from Gated SPECT Myocardial Perfusion Imaging

Transthoracic echocardiography has been increasingly used to assess left heart filling pressures. Recently some published studies have shown the limited accuracy of the individual echocardiographic parameters in advanced systolic heart failure. The purpose of Prospective consecutive patients with advanced systolic heart failure (ejection fraction ≤ 30%, New York Heart Association functional class III to IV) underwent same-day transthoracic echocardiographic and Swan-Ganz catheterization. Pulmonary capillary wedge pressure (PCWP) was measured as the average of three end expiration readings. Echocardiography measured the ratio of early to late diastolic Doppler velocity at mitral leaflet tip (E/A), the deceleration time of E velocity (dT), the ratio of early diastolic blood to tissue Doppler velocity (E/Ea), and the ratio of early diastolic blood velocity to propagation velocity of mitral valve inflow (E/Vp). SPSS (version 15) was applied for statistical analysis. A total of 60 patients were included. A significant negative correlation was found between PCWP and dT (r=0.5, P-value=0.001), and a significant positive correlation was present between PCWP and E/A (r=0.69, p-value < 0.001). Furthermore, E/Ea and E/Vp both showed a significant correlation with PCWP (r=0.55 and 0.66 respectively, P-value<0.001). ROC curve analysis showed a cut-off point of 2 for E/Vp to predict PCWP > 18 mmHg with 93% sensitivity and 87% specificity. The noninvasive assessment of LV filling pressures is certainly an important help to better manage patients with advanced systolic heart failure. In our experience, we observed a relatively good correlation between PCWP and echocardiography-derived indices such as E/A, E/Ea, and E/Vp. It was noticeable that E/Ea was not much superior in power of predicting high filling pressure to others