Myocardial steatosis is often the result of severe anemia, hypoxia, or infectious toxicity. In steatosis, small fat vacuoles appear in the myocardial cells in a bead-like arrangement. With the naked eye, rows of yellow stripes can be seen under the endocardium, especially in the papillary muscles, and the normal myocardium, which is dark red, can be arranged between them, like a tiger skin pattern, so it is called “tiger spot heart”. However, in cases of severe infection or poisoning, it often causes diffuse myocardial steatosis. The entire myocardium is uniformly cloudy and grayish yellow, and no mottling can be seen. The differentiation between myocardial steatosis and hepatic steatosis: In mild cases, there is no obvious abnormality to the eye when hepatic steatosis occurs, but in severe cases, the liver is enlarged, soft, yellowish to yellowish in color, with a blurred structure and greasy feeling on the cut surface, and in some cases, it is even as brittle as mud. Microscopically, vacuoles of varying sizes can be seen in the degenerated hepatocyte plasma, mostly around the nucleus at first, but later becoming larger and more densely scattered throughout the cytoplasm, and in severe cases, fusing into a large vacuole, mostly in the redemption of the nucleus at first, but later becoming larger and resembling fat cells. If the steatosis of the liver is accompanied by chronic liver stasis, the liver section consists of dark red stasis part and yellow-brown fatty degeneration part intertwined, forming a color similar to the cut surface of Chinese medicine betel nut, so it is called ” betel nut liver”. Frozen section, lipid droplets can be stained orange by Sudan III. The clinical significance of hepatic steatosis: hepatic steatosis is a reversible injury that can return to normal after the cause is eliminated. Severe hepatic steatosis, called fatty liver, can cause hepatomegaly, painful pressure and abnormal liver function. Long-term fatty liver can cause hepatocyte necrosis, fibroplasia, and cirrhosis. Usually the function of the myocardium is not affected and significant myocardial degeneration is not common today and has to be distinguished from myocardial fatty infiltration. Myocardial fatty infiltration: significant increase in fatty tissue in the pericardial visceral layer, appearance of adipose tissue in the myocardial interstitium, myocardial atrophy, which can lead to myocardial rupture, hemorrhage, and sudden death.