What is an acute myocardial infarction and how does it manifest?

Acute myocardial infarction is the complete blockage of a coronary artery by the formation of a thrombus (blood clot), in most cases in atheromatous plaque (a deposit of fat and calcium in the vascular wall).

The total closure of the vessel leads to a lack of blood and oxygen in the territory irrigated by the vessel, and the accumulation of toxic products, which result in the onset of intense anterior chest pain (pressure, burning, heaviness), with or without irradiation to other territories (neck, arms, shoulders, shoulder blades, shoulder blades, epigastrium), prolonged over 30 minutes, which does not subside with sublingual nitroglycerin.

The pain may be accompanied by other signs/symptoms: nausea, vomiting, choking, sweating, restlessness, palpitations, etc.

Most often there are changes on the resting electrocardiogram, echocardiographically detectable impairment of function in certain territories and changes in laboratory samples (increased blood values of markers of myocardial cell death/destruction).

Myocardial infarction without pain

Approximately one third of patients develop myocardial infarction without pain (especially diabetic patients). In these cases, only the other accompanying signs may be present, which the patient may overlook or interpret in the context of other conditions. In most cases, the presence of myocardial infarction is detected after the acute onset by cardiologic investigations (EKG, echocardiography).

Diagnosis and treatment in acute myocardial infarction

Establishing the diagnosis of myocardial infarction, even in the absence of symptoms, requires further investigations, namely coronary artery assessment by coronary angiography, and treatment depending on the outcome, the course of the condition and the risk of developing complications being the same in patients with and without symptoms.

It is a major emergency, and the only effective treatment is to restore blood flow to the affected area as quickly as possible, i.e. to open the thrombus as soon as possible after onset (within the first few hours). The more rapidly the vessel opens, the more limited the affected area in the myocardium.

The complications of inadequately treated myocardial infarction in those who have survived the acute event are:

• Decades
• Mitral valve damage, rupture of a heart wall
• Severe rhythm/driving disturbances
• The development of heart failure over time by enlarged heart chambers
• Post-stroke angina: the onset or recurrence of pain on exertion and/or at rest that severely affects quality of life
• Stroke or other vascular territory

The outcome depends on the size of the infarct, whether it is a single infarct or superimposed on another infarct, the state of the coronary arteries, the possibility of interventional/surgical resolution of the lesions, associated diseases, control of risk factors.