The Austin Flint Murmur and the a Wave of the Apexcardiogram in Aortic Regurgitation

Abstract

Hemodynamic data from 45 patients with either aortic regurgitation (with and without the Austin Flint murmur) or aortic regurgitation and mitral stenosis were correlated with the a -wave percentage amplitude of the apexcardiogram. Changes in the a wave correlated well with corresponding changes in left heart pressures but not with variations in volume. Of 15 patients in whom the ratio of the a wave to the total excursion during systole ( a /H ratio) was [See Equation in PDF file]13%, 11 had left ventricular end-diastolic pressures (LVEDP) >20 mm Hg. All patients with a /H ratios >15% had abnormal LVEDP. The converse was not true; 13 patients had elevated LVEDP with normal a /H ratios. Patients with aortic regurgitation and mitral stenosis had a /H ratios similar to those of normal subjects. The Flint murmur showed a significant correlation with left ventricular volume changes. Its presence was valuable in prediction of a large regurgitant volume and a high left ventricular stroke volume. It was also present in association with elevated left atrial mean pressure and elevated LVEDP. Thus, two ancillary findings in aortic regurgitation, a high a wave in the apexcardiogram and the Austin Flint murmur, are of value in anticipating alterations in left ventricular hemodynamics as determined by left-sided catheterization and volume studies.