The ventricular A wave: a new echocardiographic index of late diastolic filling of the left ventricle.

Echocardiography was used to evaluate the late diastolic filling period of the left ventricle in 30 normal individuals, 25 patients with left ventricular hypertrophy, normal sinus rhythm, and either a normal or delayed mitral valve closure, and 15 patients with atrial fibrillation. The echocardiographic ventricular A wave (VAW) was defined as the difference between the end-diastolic and an earlier late-diastolic internal left ventricular dimension, and it was felt to primarily reflect the atrial contribution to late diastolic filling of the left ventricle. It disappeared during ventricular pacing and was significantly smaller than normal in patients with atrial fibrillation. The VAW was significantly larger in patients with left ventricular hypertrophy and normal mitral valve closure reflecting the greater contribution by atrial contraction to late diastolic filling in these patients. In patients with left ventricular hypertrophy and delayed mitral valve closure, the VAW was normal reflecting lesser ventricular enlargement with atrial contraction than in the other patients with left ventricular hypertrophy. This suggested a greater impairment to left ventricular filling in these patients. Therefore, the VAW appears to be an indicator of abnormalities of late diastolic filling caused by left ventricular hypertrophy.