The second factor in diagnosis is the transverse enlargement of the heart. The apex may be lowered into the sixth space, but the main change is in the width of the cardiac dullness, which may extend from the left anterior axillary line to the right nipple.
Thirdly, the pulmonic second sound, heard in the second left space or over the third left costal cartilage, is accented and perhaps reduplicated. Relative in sufficiency of the mitral valve, with a normal condition of the valves, but with such dilatation of the left ventricle as to prevent the closure of the mitral orifice, may give rise to a precisely similar trio of signs.
It has been claimed that the only means of making the diagnosis of val vular incompetency as distinguished from relative insufficiency would be to find, in addition to the other signs, a pre systolic murmur due to accompanying stenosis of the diseased valve. In many eases the history of the disease and the general appearance of the patient would be equally decisive. Functional or hminic murmurs may be heard during systole at the apex and transmitted outward, but they are not associated with enlargement of the heart or accentuation of the pul monic second sound.
Etiology. — Deformities of the mitral valve leading to incompetency are caused by acute endoearditis, and still more fre quently by chronic fibroid change. Rela tive incompetency of the mitral valves may be due to failing compensation in case of an aortic lesion; or to the terminal stage of idiopathic hypertrophy of the heart (meaning that condition of the myocardium which is seen after habitual excess in muscular exertion and in the use of alcohol); also to changes in the heart secondary to chronic nephritis, arterio sclerosis, and chronic adhesive pericar ditis.
Among 5827 patients under personal observation and treatment at the general medical clinic of the New York Po-t graduate Medical School, 503 were found to be suffering from some form of disease of the heart or great thoracic vessels. These cases may be divided into two chief classes as follows: Functional dis orders, 277 cases; organic diseases, 226 cases. The organic cases were mitral re gurgitation, GO cases; mitral stenosis. 33 cases; aortic regurgitation, 7 cases: aor tic stenosis, 36 eases; tricuspid regurgi tation, 6 cases; pulmonary stenosis, 1 case; double aortic lesions, 19 eases; double mitral lesions, 12 cases; aortic stenosis and mitral regurgitation. 4
cases; aortic regurgitation and mitral stenosis, 2 cases; aortic regurgitation and mitral regurgitation, 2 cases; double aortic lesions and mitral stenosis, 1 case; double aortic lesions and mitral regurgi tation, 4 cases; combined double aortic and double mitral lesions. 2 cases: mitral lesions of doubtful character, 4 cases; aortic lesions of doubtful character, 3 cases; simple cardiac hypertrophy with out apparent valvular lesion, 10 cases; angina pectoris without valvular lesion, 3 eases; myocarditis, fatty degeneration, etc.. 6 cases; thoracic aneurism, 6 eases.
Of the total number of persons under observation, 3344 were males and 24S3 were females. Among the 3344 males, 149—or about 4.45 per cent. of the num ber—suffered from functional troubles, while 137, or 4.09 per cent., had organic heart disease. Of the 2483 females, 128, or 5.15 per cent., had functional dis ease, and 86, or about 3.46 per cent., had organic lesions. Among males one of three great causes could usually be assigned for functional disorders. In the order of frequency these were: (1) reflex disturbances due, as a rule, to digestive disorders; (2) the use of tobacco in excess, especially among ado lescent youths; and (3) too liberal in dulgence in alcoholic liquors. Among the females the causes operating to pro duce functional disorders of the heart were mainly those referable to digestive disturbances and to diseases of the blood: anaemia, chlorosis, etc. Only a minute propo-rtion could be justly attributed to excessive tea-drinking. The lnemic mur murs are almost invariably systolic in time, occurring either over the aortic or pulmonary areas, or in both regions; are usually transmitted into the great ar teries of the neck, where they may be classed as vascular bruits, and are, in a majority of cases, accompanied by a venous hum. The blood-murmurs are rarely audible below the third rib, and in more than a hundred consecutive cases the maximum intensity of these bruits was found over the mitral area in only two.