Mitral-septal angle: a new two-dimensional echocardiographic index of left ventricular performance.

The diagnostic value of a new two-dimensional echocardiographic measurement, the mitral septal angle, was evaluated as an index of left ventricular (LV) function in 122 patients. Their mean age was 56.5 years and the majority (80%) suffered from coronary artery disease, 46 with an acute myocardial infarction. Mitral septal angle was easily and reproducibly measured. An ejection fraction (EF) of greater than or equal to 50% and an angle less than or equal to 30 degrees were used as normal cut-off values. A strong negative correlation was found between the angle and radionuclide EF (-0.821) and angiographic EF (-0.82) in patients without acute myocardial infarction. For patients with acute myocardial infarction, the correlation was -0.722. For the entire group, the correlation coefficient was -0.742. In patients without acute infarction, the sensitivity, specificity, and predictive accuracy of the mitral septal angle were 92%, 86%, and 89%, respectively. In acute infarction, sensitivity dropped to 70% without change in specificity (89%). We conclude that mitral septal angle is a simple index of LV function which relates well to EF, particularly in patients with chronic heart disease.