326 DISEASES OF THE HEiRT. 



often no abnormal increase of the cardiac impulse, which, indeed, maj 

 actually become diminished in strength, or even be quite imperceptible. 

 In similar manner, the cardiac dulness may be reduced in area, rather 

 than increased, and even the heart-sounds themselves, when muffled 

 by an emphysematous lung, may fall feebly upon the ear. 



The following are the diagnostic points deduced by grouping the 

 subjective and objective signs of excentric hypertrophy of the left 

 ventricle : Visible pulsation of the carotids, loud systolic sound in the 

 larger arteries, and a full pulse, visible even in the smaller arteries ; an 

 abnormally strong heart-stroke, extending over the length of the heart ; 

 a depression of the apex, extension of the cardiac dulness, intensifica- 

 tion of the heart-sounds in the left ventricle and in the aorta, and some- 

 times a metallic click. 



Excentric hypertrophy of the right heart declares itself by the 

 following objective signs : Augmented heart-stroke, which often ex- 

 tends along the sternum and the left lobe of the liver ; dislocation of 

 the apex, which extends outward, but hardly ever downward ; exten- 

 sion in width of the cardiac dulness, intensification of the cardiac sounds 

 in the right ventricle, and in the pulmonary artery. The difference in 

 the strength of the heart-sounds is most distinctly perceptible in the 

 arteries, and particularly in the second sound, so that a stronger second 

 sound from the pulmonary artery, which is easily recognizable, even in 

 extreme emphysema, is a most important token of hypertrophy of the 

 right side of the heart. 



The sum of the objective symptoms of hypertrophy of either side 

 of the heart furnishes the physical signs of total hypertrophy. The 

 arteries and the pulse make the same manifestations as in hypertrophy 

 of the left side ; the heart-stroke is considerably stronger, extending 

 both longitudinally and transversely ; the apex is situated low down, 

 and far to the left ; the cardiac dulness is extended in all directions, and 

 ah 1 the heart-sounds are louder. 



As it is of importance, in diagnosticating the several forms of this 

 disease, to be able to compare the sounds which are audible at the 

 origins of the arteries and auriculo-ventricular orifices, we must obtain 

 an exact knowledge of the points in the thorax which correspond to 

 the arterial and venous openings, or at which, at all events, each sound 

 may be most distinctly heard and isolated from the others. The rule 

 here is to seek for the aortic sounds at the right edge of the sternum, 

 at the level of the third costal cartilage. This sound, it is true, is 

 usually more audible upon the left of the sternum than upon the right, 

 but at the left side, where the pulmonary artery lies directly over the 

 aorta, it is often difficult to determine whether a sound proceeds from 

 the aorta or pulmonary artery. For the sound of the pulmonary arterv 



