Acute myocardial infarction is usually characterized by varying degrees of chest pain, discomfort, sweating, weakness, nausea, vomiting, and arrhythmias, sometimes causing
loss of consciousness. Chest pain is the most common symptom of acute myocardial infarction and is often described as a tightness, pressure, or squeezing sensation. Pain may radiate to the jaw, neck, arms, back, and epigastrium, most often to the left arm or neck. Chest pain is more likely caused by myocardial infarction when it lasts for more than 30 minutes. The patient may complain of
shortness of breath (dyspnea) especially if the decrease in myocardial contractility due to the infarct is sufficient to cause left ventricular failure with
pulmonary congestion or even pulmonary edema.
According to some authorities, the symptomatology in women may be somewhat different from that in men. Fatigue, sleep disturbances, and dyspnea have been reported as frequently occurring prodromal symptoms which may manifest as long as one month before the actual clinically manifested ischemic event. The most common acute symptoms of the MI may include dyspnea, weakness, and fatigue. Thus in women, chest pain may be less predictive of
coronary ischemia than in men[2]
Approximately one third of all myocardial infarctions are silent, without chest pain or other symptoms.[3] This happens more often in elderly patients and patients with
diabetes mellitus.[4] They may complain though of atypical symptoms like fatigue, syncope, or weakness. Approximately half of all MI patients have experienced warning symptoms like
angina pectoris prior to the infarction.