Overview
A heart attack (myocardial infarction) occurs when the blood supply to part of the heart muscle is suddenly blocked, usually by a blood clot forming on top of a ruptured cholesterol plaque in a coronary artery. Heart muscle begins to die within minutes. Every minute without treatment increases permanent damage.
How common is it?
About 100,000 people are admitted to hospital with a heart attack in the UK each year. Heart attack is one of the leading causes of death.
Causes and risk factors
Atherosclerotic plaques (cholesterol deposits) build up in coronary artery walls over decades. When a plaque ruptures, a blood clot forms rapidly, blocking the artery and cutting off blood supply to heart muscle downstream.
Common risk factors
- Coronary artery disease
- High blood pressure
- High cholesterol
- Smoking
- Diabetes
- Obesity
- Family history of heart disease under 60
- Physical inactivity
- Stress and psychosocial factors
Symptoms
- Severe central chest pain: crushing, heavy, or squeezing in quality
- Pain spreading to the left arm, jaw, neck, or back
- Shortness of breath
- Sweating, nausea, or vomiting
- Feeling of impending doom
- Women often present atypically: breathlessness, fatigue, back or jaw pain without chest pain
When to see a doctor
Call 999 immediately. Do not drive yourself to hospital. Chew 300mg aspirin if available and not allergic while waiting for the ambulance. Time is muscle: the faster the artery is opened, the less permanent damage occurs.
Diagnosis
ECG identifies ST elevation (STEMI) requiring immediate intervention. Blood troponin levels confirm myocardial damage. Coronary angiography shows the blocked artery and is performed as part of treatment.
Treatments
Primary PCI (angioplasty and stenting)
Emergency procedure to open the blocked artery using a balloon and stent. Standard treatment for STEMI. Target: within 90 minutes of first medical contact.
Thrombolysis
Clot-dissolving drugs given intravenously if primary PCI cannot be performed within 120 minutes. Less effective than PCI but better than no treatment.
Long-term secondary prevention
Dual antiplatelet therapy, statin, ACE inhibitor, beta-blocker, and cardiac rehabilitation are all part of post-heart-attack care to prevent a second event.
Self-care and lifestyle
- Attend cardiac rehabilitation: supervised exercise, education, and psychological support after a heart attack
- Stop smoking immediately as continued smoking after a heart attack significantly increases risk of a second event
- Take all prescribed medications as directed, even when feeling well
- Follow a heart-healthy diet, exercise regularly, and manage stress
Prevention
Addressing modifiable risk factors: not smoking, controlling blood pressure and cholesterol, managing diabetes, and being physically active. Statins are highly effective at preventing first and recurrent heart attacks in high-risk individuals.