What are the features of a myocardial infarction (MI) or cardiac stroke?

From the Guidelines

A myocardial infarction (MI), commonly known as a heart attack, is characterized by chest pain or discomfort that typically feels like pressure, squeezing, fullness, or pain in the center or left side of the chest, and is caused by a blockage of blood flow to part of the heart muscle, usually by a blood clot forming in a coronary artery narrowed by atherosclerosis, as defined by the detection of a rise and/or fall of cardiac biomarkers with at least one value above the 99th percentile upper reference limit and with at least one of the following: symptoms of ischemia, new or presumed new significant ST-segment–T wave changes or new left bundle branch block, development of pathological Q waves in the electrocardiogram, imaging evidence of new loss of viable myocardium or new regional wall motion abnormality, or identification of an intracoronary thrombus by angiography or autopsy 1. The features of a myocardial infarction (MI) or cardiac stroke include:

• Chest pain or discomfort that typically feels like pressure, squeezing, fullness, or pain in the center or left side of the chest
• Pain that often radiates to the jaw, neck, back, arms (particularly the left arm), and sometimes the upper abdomen
• Additional symptoms such as shortness of breath, cold sweats, nausea, vomiting, lightheadedness, and fatigue
• The discomfort associated with acute MI usually lasts >20 min, and may be accompanied by diaphoresis, nausea or syncope 1
• MI may occur with atypical symptoms—such as palpitations or cardiac arrest—or even without symptoms; for example in women, the elderly, diabetics, or post-operative and critically ill patients 1
• The Third Universal Definition of Myocardial Infarction consensus document classifies MI into 5 types, based on pathological, clinical, and prognostic differences, along with different treatment strategies 1
• Immediate medical attention is crucial, with treatment focusing on restoring blood flow through medications like aspirin, antiplatelet drugs, anticoagulants, thrombolytics, and procedures such as angioplasty or coronary artery bypass surgery
• Time is critical - the phrase "time is muscle" emphasizes that faster treatment means less heart damage
• It's essential to note that a cardiac stroke is not a medical term; strokes affect the brain, while heart attacks affect the heart, though both involve blocked blood flow to vital organs.

From the Research

Features of Cardiac Stroke

The features of cardiac stroke, also known as myocardial infarction (MI), can be identified through various symptoms and diagnostic tests. Some of the key features include:

• Chest pain that travels from the left arm to the neck 2
• Shortness of breath, sweating, nausea, vomiting, abnormal heart beating, anxiety, fatigue, weakness, stress, and depression 2
• Atypical symptoms such as nausea, vomiting, and shortness of breath, which are more common in females 3
• Prodromal symptoms such as fatigue in the days leading up to MI, which are also more common in females 3
• Electrocardiogram (ECG) changes, such as ST-segment elevation, which can indicate the presence of a myocardial infarction 4
• Elevated cardiac troponin levels, which can indicate damage to the heart muscle 4

Diagnostic Tests

Diagnostic tests that can help identify the features of cardiac stroke include:

• ECG, which can show changes in the heart's electrical activity 2, 4
• Coronary angiography, which can show the narrowing of coronary arteries 2
• X-ray of the heart and blood vessels, which can show the extent of damage to the heart muscle 2
• Blood tests, such as troponin levels, which can indicate damage to the heart muscle 4, 5

Sex Differences

There are sex differences in the features of cardiac stroke, with females more likely to present with atypical symptoms and prodromal symptoms 3. Females also tend to have a higher incidence of MI not related to plaque rupture or erosion, and have increased microvasculature resistance when they have an MI 3.

Treatment

The treatment of cardiac stroke typically involves:

• Aspirin, which can help prevent blood from clotting 2, 4
• Nitroglycerin, which can help relieve chest pain 2, 4
• Beta blockers, which can help lower blood pressure and improve the oxygen demand of the heart 2
• Thrombolytic therapy, which can help dissolve arterial blockages 2, 4
• Percutaneous coronary intervention (PCI), which can help restore blood flow to the heart muscle 4