Myocardial infarction (heart attack)
What happens in a heart attack
Blood flow to part of the heart muscle gets blocked, usually when plaque in a coronary artery ruptures and a clot forms on top. No blood means tissue death in that area.
Core symptoms
Chest pain or discomfort for 10 minutes or more, shortness of breath, nausea or vomiting, dizziness, cold sweat, fatigue, pain in the arm, neck, jaw, or stomach, or even loss of consciousness.
Silent MI: It can happen with no classic symptoms, especially in people with diabetes or older adults.
Main causes
- Plaque rupture from coronary artery disease — the most common.
- Coronary artery spasm — the vessel suddenly tightens.
- Coronary embolism — a clot from elsewhere lodges in a heart artery.
- Spontaneous coronary artery dissection — a sudden tear in the artery wall.
- Anomalous coronary artery — born with an artery in the wrong spot.
- Hypertensive crisis — blood pressure dangerously high.
- Microvascular coronary disease — the tiny vessels don’t work the right way.
Risk factors
Hypertension, smoking, diabetes, lack of exercise, obesity, excess alcohol, family history, and a diet high in salt and saturated fat.
Complications
Heart failure, arrhythmias, cardiogenic shock, cardiac arrest, and coma.
Left ventricular thrombus: A clot in the left chamber can break off, travel to the brain, and cause a stroke.
Diagnosis
- ECG: Looks for ST changes and arrhythmias.
- Troponin blood test: A cardiac protein that leaks when heart muscle is damaged.
- Echocardiogram: Shows how well the heart pumps.
- Coronary angiography: The gold standard to see blockages.
- CT, MRI, or PET: Check for narrowing, blood flow, and areas not getting a supply of blood.
Treatment
- PCI, or stenting: A catheter and balloon open the artery, then a stent goes in.
- CABG: Bypass surgery for multiple blockages.
- Medicines: Aspirin, nitroglycerin, ACE inhibitors, beta blockers, statins, anticoagulants, and antiarrhythmics.
Conclusion
If you suspect an MI, reach a hospital immediately. Don’t wait. Chewing aspirin while waiting for help can improve outcomes, if you are not allergic to it.