Physical Examination And Diagnosis Of Acute Myocardial Infarction
Examining A Patient
This is characterized by the occurrence of severe retrosternal pain with the characteristic radiations. The pain is usually severe and excruciating, but at times it may be mild and rarely, pain may be absent. The pain is described as crushing, tearing, bursting, burning, lancing or vague. The severity of the pain does not bear a close relationship to the extent of infarct, but the duration of pain, the quantity of analgesics required to arrest the pain are related to its extent. The pain generally lasts for more than 30 minutes and the attack occurs during rest. These are severe anxiety and a feeling of impending death, profuse sweating, dypsnea, shock, cardiac arrhythmias, syncope, nausea, vomiting and epigastric pain.
Signs: In 20% of cases, the symptoms may be trivial and physical examination may be unrewarding. In the majority, the findings and sudden onset of pulmonary edema are suggestive of acute left ventricular failure. In cardiogenic shock, the extremities are cold and cyanosed and the blood pressure is low and often unrecordable. Heart rate is variable. In the initial stages, severe bradycardia may occur in some cases as a result of vagal tone. Others show tachycardia and arrhythmias such as frequent ventricular ectopics, atrial fibrillation or ventricular fibrillation. The blood pressure drops in most cases, but sometimes it may remain normal or even be elevated as a result of intense vasoconstriction. The jugular venous pressure may be elevated, if there is congestive heart failure. About 24-48 hours after the infarct, fever may occur as a response to tissue necrosis.
Physical examination of the heart reveals muffling of sounds, presence of gallop suggesting ventricular failure, arrhythmias and accentuation of the pulmonary second sound (P2), as a result of rise of pulmonary artery pressure. On the second or third day, pericardial friction rub may be heard or a pericardial effusion may develop. If complications develop these will be clinically evident.
Diagnosis: Strong clinical suspicion is needed for early diagnosis. It should be remembered that in the middle-aged and elderly, one of the common causes for chest pain is myocardial infarction. Clinical suspicion is strengthened by the presence of the characteristic radiation and the associated phenomena. Even in the absence of pain, myocardial infarction should be suspected if a middle-aged person develops any of the complications suddenly.
© 2014 Funom Theophilus Makama