THE HEART-SOUNDS. 91 



contraction ; d, closure of the aortic valves, and e of the pulmonary ; e, /, the 

 time the ventricle is relaxed (Fig. 30.) 



In curve P (much reduced), taken from a case of marked hypertrophy with 

 dilatation, the ventricular contraction, b c, is usually very great, while the time 

 occupied by the contraction is not much increased. P and Q were obtained from 

 a man suffering from marked eccentric hypertrophy of the left ventricle, in con- 

 sequence of insufficiency of the aortic valves. Curve Q was taken intentionally 

 over the auriculo-ventricular groove, where a falling in of the chest-wall occurred 

 during systole ; nevertheless, the individual events occurring in the heart are 

 indicated. 



Fig. E is from a case of aortic stenosis. The auricular contraction (a, b) lasts 

 only a short time ; the ventricular systole is obviously lengthened, and after a 

 short elevation (b, c) shows a series of fine indentations (c, e) caused by the blood 

 being pressed through the narrowed and roughened aorta. 



Fig. F, from a case of insufficiency of the mitral valve, shows (a, b) well marked 

 on account of the increased activity of the left auricle, while the shock (d) from 

 the closure of the aortic valves is small on account of the diminished tension in 

 the arterial system. On the other hand, the shock from the accentuated pul- 

 monary sound (e) is very great, and is in the apex of the curve. On account of 

 the great tension in the pulmonary artery, the second pulmonary tone may be so 

 strong, and succeed the second aortic sound (d) so rapidly, that both almost merge 

 completely into each other (H and K). 



The curve of stenosis of the mitral orifice (G) shows a long irregular notched 

 auricular contraction (a, b) caused by the blood being forced through an irregular 

 narrow orifice. The ventricular contraction (b, c) is feeble on account of its being 

 imperfectly filled. The closures of the two valves, d and e, are relatively far apart, 

 and one can hear distinctly a reduplicated second sound. The aortic valves close 

 rapidly because the aorta is imperfectly supplied with blood, while the more 

 copious inflow of blood into the pulmonary artery causes a later contraction of its 

 valves (Geigel). 



If the heart beats rapidly and feebly if the blood-pressure in the aorta and 

 pulmonary artery be low, the signs of closure of the pulmonary valves may be 

 absent as in curve L taken from a girl suffering from nervous palpitation and 

 morbus Based owii. 



In very rare cases of insufficiency of the mitral valve, it has been observed that 

 at certain times both ventricles contract simultaneously, as in a normal heart, but 

 that this alternates with a condition where the right ventricle alone seems to con- 

 tract. Curve M is such a curve obtained by Malbranc, who called this conditioa 

 intermittent hemisystole. The first curve (I) is like a normal curve, during which 

 the whole heart acted as usual. The curve II, however, is caused by the right 

 side of the heart alone ; it wants the closure of the aortic valves, d, and there was 

 no pulse in the arteries. Owing to insufficiency of the tricuspid valve, the same 

 person had a venous pulse with every cardiac impulse, so that the arterial and 

 venous pulses first occurred together, and then the venous pulse alone occurred. 



In these cases (Skoda, v. Bauiberger, Leyden) the mitral insufficiency leads to 

 overflowing of the right ventricle, while the left is nearly empty, so that the right 

 side requires to contract more energetically than the left. It does not seem that 

 the right ventricle alone contracts in these cases, but rather that the action of the 

 left side is very feeble. 



53. The Heart-Sounds. 



On listening over the region of the heart in a healthy man, either 

 with the ear applied directly to the chest-wall, or by means of a 



