1954 Volume 59 Issue 3 Pages 307-313
1. Intracardiac heart sounds of dogs and men were recorded on a tape-recorder and these recordings were heard by many cardiologists at the Annual Meeting of the Society of Angiocardiology of Japan in 1953.
2. The data obtained to date by the present authors indicate that there exists a certain amount of blood whirlpool inside the heart cavities and arteries. Although this whirlpool is mostly in audible range, the damping effect of heart and arterial walls makes it impossible to hear these sounds upon chest wall in normal healthy case.
3. When the catheter tip is placed in blood stream, chiefly course sounds due to blood whirlpool is recorded, and when the tip is contacted with the inner wall of the heart, chiefly vibrations of a solid structure is recorded. This latter is thought to be one similar to heart sounds obtained from chest wall.
The authors take this opportunity to express their gratitude to Prof. Tasaka for the reviewing of this manuscript.
