[Atrial flutter with an audible atrial sound (author's transl)]

In a case of rheumatic valve disease atrial sounds could be heard and recorded on the phonocardiogram during atrial flutter at a rate of 260/min and an atrioventricular block of 3:1 and 5:1. The atrial flutter sounds were also recorded in the apex-cardiogram and as a slight but rapid motion of the anterior mitral valve leaflet in the echocardiogram. These atrial sounds were recorded both in systole and diastole and disappeared after cardiac failure had been treated and sinus rhythm restored. This case and 19 others reported in the medical literature indicate that for atrial sounds to become audible requires high-grade atrioventricular block and increased atrial contractions with increased ventricular filling. The sounds have been proven to originate in the atrium, the characteristics of the sound being similar to those of an opening snap.