Average weight in adult male, about 300-350 grm.
Average weight in adult female, about 250 grm.
Normal limits, 200-350 grm.
Weight of heart to body-weight in adult male, 1:169; in the female, 1:162.
Circumference at base of ventricles 25.8 cm., length of ventricles 8-9 cm., breadth 8.5-10.5 cm., thickness 3-3.6 cm.; minimal measurements are for the female. Auricles are 5-6 cm. in length. Compare ventricles as to size.
Note form (long, cylindrical, pyramidal, broad, short, round, etc.) In hypertrophy of the left ventricle the heart is longer and more cylindrical; in hypertrophy of the right it is broader and more rounded. Normally the apex is formed by the left ventricle, the sulcus longitudinalis running to the apex and nearly dividing the heart into halves. In hypertrophy of the right ventricle the apex is formed by this ventricle, the sulcus longitudinalis passing to the left of the apex; in hypertrophy of the left ventricle the longitudinal sulcus runs to the right of the apex. What part of the heart lies anteriorly? (Normally a large part of the right ventricle.)
The consistence of the organ, particularly that of the ventricles, should be noted (firm, flabby, soft, etc.). Condition of the heart-chambers (empty, contracted, dilated, full). Rigor mortis should be removed by kneading or by the application of heat. The amount of subepicardial fat, its color, translucency, occurrence of serous atrophy, œdema, subepicardial hemorrhage, etc., are to be noted. In marasmus a serous or mucoid degeneration of the subepicardial fat is not uncommon. The subepicardial fat increases with age, and is normally most abundant along the grooves and blood-vessels, particularly the auriculoventricular grooves and on the right ventricle. Normally the color of the heart-muscle of the ventricles should be seen through the epicardium. The fat is increased in obesity, chronic alcoholism, chronic anæmia, tuberculosis, etc. When the fat-infiltration is so marked that the muscle cannot be seen the condition is known as adipositas or obesitas cordis, or in extreme cases as lipoma cordis capsulare.
7. Right Heart. Note amount of blood contained in right chambers (over-distended in death from asphyxiation, pneumonia, etc.), also its consistence (thick, thin, watery), color (light, dark, red, yellowish, chocolate, purplish), blood-clots (size, color, cruor, lardaceous clots, chicken-fat clots, pus-like clots, consistence, moisture), presence of free fat, gas or air, diffusion of hæmoglobin, presence of bile-pigment in blood. Note also amount and character of blood in venæ cavæ. The size of auricular and ventricular cavities should be estimated, noting condition of trabeculæ and papillary muscles (atrophic, flattened, hypertrophic, fatty, fibroid, calcification). The musculature of the ventricular walls is examined as to its thickness (normally the right ventricle wall is 4-5 mm. thick). Postmortem contraction should not be mistaken for hypertrophy. The color of the heart-muscle normally is pinkish in infants, flesh-red in adults, and brownish-red in old age and in atrophy following compensatory hypertrophy (brown atrophy). Under normal conditions the muscle is translucent. In cloudy swelling the heart-muscle appears cloudy and opaque as if cooked. Fatty degeneration appears as yellowish, opaque patches or streaks (“tiger-heart”), particularly in the papillary muscles and trabeculæ. In severe intoxications the process may be diffuse, and the entire musculature appear cream-colored or yellowish and opaque. The consistence may be firm, flabby, soft, putty-like; localized areas may be caseous. Infarcted areas are soft when fresh (myomalacia cordis). The consistence is increased in atrophy, fibroid heart, chronic interstitial myocarditis, syphilis, etc. Cloudy swelling and fatty degeneration make the heart muscle softer and more friable. In postmortem decomposition the heart as a whole becomes soft. Normally the endocardium should be gray, delicate, thin and transparent. The chordæ tendinæ are long, narrow and delicate. Note thickenings of endocardium and chordæ tendinæ, presence of thrombi (dry, brick-red, yellowish or gray, firmer than clots and adherent to the endocardium, often show simple softening, which should not be mistaken for pus; may be parietal, polypoid, valvular or free). The endocardium may be stained diffusely yellow (bile) or brown (methæmoglobin). Creamy or yellowish opacities of the intima are due to fatty degeneration.
8. Left Heart. Note same things in left side of heart as on right. In cardiac paralysis left ventricle is filled with blood if rigor mortis has not set in. Left ventricle wall is 10-15 mm. thick normally; may become 30 mm. thick in hypertrophy. Papillary muscles and trabeculæ may be markedly hypertrophic, but in the greatly dilated heart (aortic insufficiency) may be much flattened. The septum of the ventricles may share in the hypertrophy of either ventricle and when hypertrophic bulges into the cavity of the unaffected side. Examine wall of left ventricle, particularly near the apex, for infarcts, fibroid patches, aneurismal dilatation, rupture, fatty degeneration, thrombi, etc. Look particularly for pathologic conditions involving the atrioventricular bundle.
9. Orifices and Valves. Orifices should measure as follows:—Tricuspid (12-12.7 cm.), mitral (10.4-10.9 cm.), pulmonary (8.9-9.2 cm.), aorta (7.7-8 cm.). Rough measurements may be taken with the fingers, tricuspid admitting three, mitral two, pulmonary one and a half, aorta thumb. The orifices may be measured by graduated cones, or in the ordinary way after the heart is sectioned. Normally the edges of the valve-flaps should be delicate, smooth and thin. Examine for vegetations, thrombi, induration, thickening, contractions, ulcerations, tears, perforations, defects, calcification, atheroma, valvular aneurism, etc. Note thickening, contraction, adhesion, shortening, etc., of the chordæ tendinæ. When the tendons are long, narrow and thread-like, and without adhesions, the probabilities are that a lesion of the mitral orifice was not present.