Myocardial infarction: prognosis and rehabilitation

Rehabilitation and treatment at the outpatient stage

Physical activity is gradually increased during the first 3 to 6 weeks after discharge. Resumption of sexual activity, which is often a concern for the patient, and other moderate physical activity are encouraged. If good cardiac function is maintained for 6 weeks after acute myocardial infarction, most patients can resume normal activity. A rational physical activity program, taking into account lifestyle, age, and cardiac condition, reduces the risk of ischemic events and increases overall well-being.

The acute period of the disease and treatment of ACS should be used to develop a strong motivation for risk factor modification in the patient. When assessing the patient's physical and emotional status and discussing them with the patient, it is necessary to talk about lifestyle (including smoking, diet, work and rest regimen, the need for physical exercise), since eliminating risk factors can improve the prognosis.

Medicines. Some drugs significantly reduce the risk of mortality after myocardial infarction and should always be used unless there are contraindications or intolerance.

Acetylsalicylic acid reduces mortality and the frequency of repeated infarctions in patients who have had a myocardial infarction by 15 to 30%. Rapidly dissolving aspirin at a dose of 81 mg once a day is recommended for long-term use. Data indicate that the simultaneous administration of warfarin with or without acetylsalicylic acid reduces mortality and the frequency of repeated infarctions.

B-blockers are considered standard therapy. The most widely available b-blockers (such as acebutolol, atenolol, metoprolol, propranolol, timolol) reduce mortality after myocardial infarction by approximately 25% for at least 7 years.

ACE inhibitors are prescribed to all patients who have had a myocardial infarction. These drugs can provide long-term protection for the heart by improving endothelial function. If ACE inhibitors are not tolerated, for example due to cough or allergic rash (but not vascular edema or renal failure), they can be replaced by angiotensin II receptor blockers.

Patients are also indicated for HMG-CoA reductase inhibitors (statins). Lowering cholesterol levels after myocardial infarction reduces the incidence of recurrent ischemic events and mortality in patients with elevated or normal cholesterol levels. Statins are likely to be beneficial in patients after myocardial infarction, regardless of initial cholesterol levels. Patients after myocardial infarction who have dyslipidemia associated with low HDL or elevated triglycerides may benefit from fibrates, but their efficacy has not yet been experimentally confirmed. Hypolipidemic therapy is indicated for a long time if there are no significant adverse effects from it.

Myocardial infarction prognosis

Unstable angina. About 30% of patients with unstable angina will have a myocardial infarction within 3 months of the episode; sudden death occurs less frequently. Detectable ECG changes along with chest pain indicate a higher risk of subsequent myocardial infarction or death.

Non-ST-segment elevation myocardial infarction and ST-segment elevation myocardial infarction. The overall mortality rate is approximately 30%, with 50% to 60% of these patients dying prehospital (usually due to ventricular fibrillation). In-hospital mortality is approximately 10% (mostly due to cardiogenic shock) but varies significantly with the severity of heart failure. Most patients dying due to cardiogenic shock have a combination of infarction and postinfarction cardiosclerosis, or the new myocardial infarction involves at least 50% of the left ventricular mass. Five clinical characteristics predict 90% of mortality in patients with STHM: older age (31% of overall mortality), low systolic BP (24%), class > 1 (15%), high heart rate (12%), and anterior location (6%). Mortality is slightly higher among patients with diabetes mellitus and women.

Mortality among patients undergoing initial hospitalization is 8% to 10% in the first year after acute myocardial infarction. Most deaths occur in the first 3 to 4 months. Persistent ventricular arrhythmia, heart failure, poor ventricular function, and persistent ischemia are markers of high risk. Many experts recommend performing a stress test with an ECG before or within 6 weeks of hospital discharge. A good test result with no changes in ECG findings is associated with a favorable prognosis; further testing is usually unnecessary. Low exercise tolerance is associated with a poor prognosis.

The state of cardiac function after recovery depends largely on how much functioning myocardium remains after the acute attack. Scars from previous myocardial infarctions are added to the new damage. In case of damage > 50 of the left ventricular mass, a long life expectancy is unlikely.

Killip classification and mortality from acute myocardial infarction*

Class	RO 2	Symptoms	Hospital mortality, %
1	Normal	No signs of left ventricular failure	3-5
II	Slightly reduced	Mild to moderate LV failure	6-10
III	Reduced	Severe left ventricular failure, pulmonary edema	20-30
IV	Severe degree of insufficiency	Cardiogenic shock: arterial hypotension, tachycardia, impaired consciousness, cold extremities, oliguria, hypoxia	>80

Determined during repeated examinations of the patient during the course of the disease. Determined if the patient breathes room air.