Cineradiographic Studies of the Early Systolic Click in Aortic Valve Stenosis
An early systolic click and a normal or accentuated aortic second sound have been found in cases of aortic valve stenosis characterized cineradiographically by a mobile, dome-shaped valve. Impaired valve mobility was usually associated with a systolic click of low intensity, and in the presence of an immobile aortic valve there was no systolic click. The aortic second sound was correspondingly diminished or absent.
Early systolic clicks and loud aortic closure sounds were also present in patients in whom a diseased aortic valve had been replaced by three Teflon prosthetic leaflets. In most of these patients there was no systolic click before insertion of the prosthesis.
In the patients studied, the systolic click occurred at the end of the opening movement of the aortic valve at the onset of left ventricular ejection. It followed the crossover point of the left ventricular and aortic pressure pulses by a time interval ranging from 15 to 45 msec. (average 33 msec.).
The opening movement of the valve was thought to produce the systolic click by causing sudden tension of the valve membrane or sudden alteration in the velocity of blood flow. By analogy with the opening snap in mitral stenosis, the early systolic click may be regarded as the "opening snap" of the aortic valve. A systolic click is clinical evidence of a mobile aortic valve in patients with aortic valve disease.
- © 1965 American Heart Association, Inc.