When there is a problem with the heart, the patient will have a fever, but not necessarily all patients with heart disease will have a fever, common cardiac diseases that can lead to fever are myocarditis, in the patient has obvious myocarditis will usually have a typical fever, the body temperature will continue to be in the 38-39 ℃, the patient will be accompanied by palpitations, chest tightness, shortness of breath, accompanied by dyspnea, fatigue around the body, coughing, coughing up sputum, body aches and pains. Clinical symptoms and manifestations. Usually myocarditis caused by bacterial or viral and other pathogenic microorganisms after infection, there will be obvious fever symptoms. In addition, when myocardial infarction, there will be markers of myocardial necrosis in the body, and these markers of necrosis include tumor necrosis factor, leukotrienes and other substances, which will also cause the body to have fever when a large amount of these substances enter into the bloodstream, but at this time, the type of fever is dominated by low-grade fever and moderate fever, and the body temperature usually doesn’t exceed 38.5℃.