38 Op. cit. (foot-note).
Auscultation.—In the heart the single, constant sign that has been observed consists in the modified tonality of the normal sounds. These are rapid, irregular, muffled, obscured, and distant. There is notable inequality also in the strength of successive beats, which is obviously explained by the great difficulty the blood encounters in traversing the heart. Now, as I have seen in frequent autopsies that the valvular mechanism of the left heart is ordinarily free from any fibrinous deposit, it is readily understood that it can produce the two sounds normal as regards situation and time, but greatly modified in transmission.
Percussion.—Percussion, except in particular cases which are rare, and in which the cavities are much distended by their contents, will only furnish us with negative signs. When the ventricles are swollen by large coagula, the percussion dulness will be extended laterally. As the right cavity is usually the seat of the deposit, it will be particularly marked toward the right of the sternum. In those instances where the area of præcordial dulness had been determined before the formation of the fibrinous concretion this extension becomes a physical sign of great value. It is to Piorry and the use of the plessimeter that we owe whatever of exactness belongs in like cases to this method of examination.
Inspection and Palpation.—The cardiac impulse may be unaffected by the presence of the thrombus, and if it has been regular in rhythm previous to its formation it may still remain so. This condition is infrequent, however, and usually the pulsations become irregular, tumultuous, and rapid. The force of successive beats will also be different. These signs can be determined by the sight and touch.
Pulse.—The characters of the pulse are variable. Sometimes it presents manifest inequalities, occasional intermittences, and is extremely frequent. It may be quite feeble in the beginning, and afterward gain in strength. Sometimes, in spite of its weakness and depressibility, it retains its regularity and its rhythm is unchanged. The coagulum existing in the cardiac cavities, especially on the right side, explains the variations of the pulse. Effectively, at each contraction of the ventricle this chamber, containing a less quantity of liquid blood, projects a smaller amount of venous blood to the lungs. Besides, this quantity is insufficient to replace the volume of revivified blood which leaves the lung with each inspiration. Soon the left cardiac cavities contract with but small power upon an amount of blood below the normal, and yet it is with this supply that the left heart must satisfy the needs of all the organs. The arteries during life become nearly empty, and it is to this condition, as well as to the lack of synchronism between the action of the two sides of the heart, should be attributed the signs we recognize in the characters of the pulse.39
39 Robinson, loc. cit.
In some instances of cardiac concretions the sonority of the chest remains normal. In others it is obviously augmented, and even by percussion very lightly performed a sound of raised pitch is produced. According to Richardson, this acute emphysema is the direct result of an insufficient blood-supply in the capillaries which surround the pulmonary alveoli. Whilst such a condition may often be observed amongst children, it is not unknown with adults. The affirmation, therefore, of Walshe, that it can only be observed in young people, and that in adults its place is supplied by considerable pulmonary congestion, is not exact. Since Richardson first called attention to the exaggerated sonority of the lungs in cases of heart-clot, other observers have also referred to it. Lavirotte (1864) particularly has insisted on it as a proof of fibrinous deposition in the right heart, and has demonstrated with pathological specimens that it was occasioned by the exsanguinated state of the lungs and their hyperdistension with air.40 On the other hand, Raynaud41 states that when the left cavities are the seat of the concretion there is considerable stagnation in the lungs, and they show signs of great congestion. Thoracic percussion becomes less resonant, and subcrepitant râles are heard in an extended area. Sometimes, even, a moderate hæmoptysis takes place. These signs of emphysema on one hand, of congestion on the other, are not spoken of by the majority of writers on this subject; yet when they are present they will serve to fix our diagnosis and render it more certain. With respect to emphysema, especially amongst children, we should mention its great frequency, and on this account perhaps proper value has not been given to it when found at the autopsy of a child whose death has been occasioned by cardiac thrombosis. When the cardiac thrombus is present in the right side of the heart, Legroux42 has shown that there will be a more or less turgid condition of the veins of the neck, and perhaps also of the right upper limb. With this distension of the veins we shall remark, according to him, a partial or general infiltration of the subcutaneous tissues. Sometimes the oedematous condition is limited to the face and neck; occasionally it extends below the diaphragm, especially on the right side of the body. The extent of the oedema will depend upon the number and size of the prolongations which are given out by the main coagulum. Occasionally these prolongations have been found not only blocking up the pulmonary artery, but also filling one or both venæ cavæ and branching out as far as the jugular and subclavian veins.
40 Congrès Medico-Chirurgical, Lyon, 1864.
41 Dict. de Méd. et de Chirurgie, vol. viii. p. 573.
42 Gazette hébdomadaire, 1856.