Myocardial infarction (MI), commonly known as a heart attack, is brought about by a sudden blockage of blood flow to a section of the heart muscle. The heart tissue experiences oxygen deprivation, leading to damage or death of the heart muscle. The amount of damage depends upon the location of the block and how quickly the blood supply is restored. It may lead to complications and, in extreme cases, death if left unaddressed. Myocardial Infarction is a clinical emergency and one of the top causes of death globally.

What is myocardial infarction or heart attack?

A myocardial infarction occurs when one or more of the coronary arteries that bring blood to the heart become blocked. It happens most frequently due to a blockage caused by plaque deposition within the inner lining of an artery, which leads to the formation of a blood clot, partly or completely blocking the blood flow to the heart muscle. Because of the lack of oxygen, the affected heart muscle begins to die and interferes with the heart's ability to pump blood adequately. This depends on the location and size of the blockage and the duration for which the heart muscle does not receive blood.

Symptoms of Myocardial Infarction

The symptoms of a heart attack differ from one person to another but typically show classical symptoms such as:

• Chest pain or discomfort
• Pain in other parts of the body
• Shortness of breath
• Cold sweat
• Nausea or vomiting
• Dizziness or fainting

It's important to note that symptoms differ by gender. Women are likely to experience atypical symptoms more often than men. In fact, most of the symptoms have variants, such as extreme exhaustion, nausea, backache, or jaw pain.

Causes of Myocardial Infarction

The most common reason for myocardial infarction is CAD. CAD is a disease whereby the coronary arteries, that provide blood to the heart, become restricted or plugged due to the formation of plaques. These are a combination of cholesterol, calcium, and many other materials that may eventually turn hard, hence giving rise to the condition named atherosclerosis.

A rupture of the plaque may initiate the formation of a blood clot that can entirely or partially block the artery. Some other less common causes of myocardial infarction are:

• Coronary artery spasm
• Coronary embolism
• Severe anaemia

Diagnosis

Prompt diagnosis of myocardial infarction is essential for effective treatment. Some diagnostic measures include:

• ECG: ECG will record the electrical activity within the heart and may show some abnormalities that suggest a heart attack. Specific patterns of ECG may be used to confirm or deny the diagnosis and will give an estimation of the severity of the attack.
• Blood tests: In a heart attack, heart muscle cells are damaged, and some proteins inside them get released into the bloodstream, such as troponin. Elevated levels of these markers confirm the presence of a heart attack.
• Coronary Angiography: This procedure involves injecting a special dye into the coronary arteries through a catheter to visualize blockages on X-ray imaging.
• Echocardiogram: An echocardiogram, which is actually an ultrasound of the heart, can assess the function of the heart after a heart attack and assess areas of the heart muscle that are damaged.

Treatment and Management

Treatment of a myocardial infarction begins with an immediate restoration of the blood flow to the heart muscle to cut down the damage as soon as possible. There are several treatment methods, which include:

Medications

Some drugs such as thrombolytics, antiplatelet drugs, nitroglycerin, and beta-blockers aid in treating a heart attack but are often the second line of treatment.

Invasive Therapy

• Catheter-based: Angioplasty or percutaneous coronary intervention
• Surgical: Coronary artery bypass grafting (CABG)

Lifestyle changes

As part of the long-term management of myocardial infarction, heart-healthy habits become imperative. This involves stopping smoking, eating a healthy diet, exercising regularly, and managing other conditions such as high blood pressure and diabetes.