Abstract 720: Real-Time 3-Dimensional Echocardiography is an Indispensable Tool for Assessing Right Ventricular Function in Patients with Right Ventricular Pressure Overload
Right ventricular (RV) volume and ejection fraction (EF) by 3-dimensional echocardiography (3DE) are validated by magnetic resonance imaging. Two-dimensional echocardiography (2DE) is not reliable in determining RV size and function when abnormal hemodynamics is present. Eighty patients were analyzed. 2DE obtained RV end-diastolic area (EDA), end-systolic area (ESA), fractional area change (FAC) and systolic pressure (SP). 3DE obtained RV end-diastolic volume (EDV), end-systolic volume (ESV) and EF. RV dilation was defined as EDA >28 cm2 and EDV >147 ml. Normal RV function was defined as FAC >32% and EF >49%. 3DE variables were used as gold standard. RV-EDA, ESA, FAC and SP were 23 ± 8 cm2, 15 ± 7 cm2, 36 ± 12% and 41 ± 19 mm Hg, respectively. RV-EDV, ESV and EF were 114 ± 67 ml, 61 ± 40 ml and 47 ± 9%, respectively. RV-EDA, ESA and FAC were correlated with RV-EDV, ESV and EF, respectively (all p <0.001). RV dilation by 2DE predicted RV dilation by 3DE with sensitivity of 72% and specificity of 94%. In contrast, normal RV function by 2DE predicted normal RV function by 3DE with sensitivity of 63% and specificity of 82%. Patients with normal RV function by 2DE but not 3DE (n = 19) had greater RV-SP than those with normal RV function both by 2DE and 3DE (n = 33; 48 ± 22 mmHg vs. 34 ± 10 mmHg, p = 0.02). Among patients with normal RV function by 2DE, 10 of 11 patients (91%) with RV-SP >52 mmHg showed RV dysfunction by 3DE. RV area and FAC by 2DE were correlated with RV volume and EF by 3DE; however, 2DE overestimated RV function in patients with RV pressure overload. 3DE may be indispensable for assessing RV function in patients with RV pressure overload.