Overview
A heart attack occurs when blood flow to part of the heart muscle is blocked, usually by a blood clot forming in a coronary artery. Without blood and oxygen, heart muscle begins to die within minutes. A heart attack is a medical emergency requiring immediate treatment. The sooner treatment is given, the more heart muscle can be saved. Knowing the warning signs and acting fast can be life-saving.
Causes and risk factors
The following factors are associated with the development of Heart Attack (Myocardial Infarction):
- Coronary artery disease — build-up of plaque in arteries (atherosclerosis)
- Blood clot forming in a narrowed coronary artery
- Coronary artery spasm
- Smoking
- High blood pressure
- High cholesterol
- Diabetes
- Obesity
- Family history
- Sedentary lifestyle
- Excessive alcohol
- Stress
Signs and symptoms
Common signs and symptoms of Heart Attack (Myocardial Infarction) include:
- Chest pain or pressure — may feel like squeezing, fullness, or tightening
- Pain spreading to arm (usually left), jaw, neck, or back
- Shortness of breath
- Nausea and cold sweat
- Lightheadedness or dizziness
- Fatigue
- Women may have atypical symptoms: nausea, jaw pain, extreme fatigue without chest pain
Diagnosis
Heart Attack (Myocardial Infarction) is typically diagnosed through a combination of medical history, physical examination, and appropriate investigations such as blood tests, imaging, or specialist review, depending on the specific condition and presentation. Your doctor will consider all relevant symptoms and risk factors before making a diagnosis.
Treatment options
Treatment approaches for Heart Attack (Myocardial Infarction) may include:
- Call 999/112 immediately — do not drive yourself
- Aspirin chewed immediately while waiting for ambulance
- Percutaneous coronary intervention (PCI/angioplasty) to open blocked artery
- Thrombolysis (clot-busting drugs) if PCI not available quickly
- Coronary artery bypass surgery in some cases
- Long-term medications: aspirin, statins, beta-blockers, ACE inhibitors
- Cardiac rehabilitation programme
- Lifestyle changes
Prevention
Stop smoking, control blood pressure and cholesterol, maintain healthy weight, exercise regularly, eat heart-healthy diet, manage diabetes and stress.
Complications
If left untreated or poorly managed, Heart Attack (Myocardial Infarction) can lead to complications including:
Heart failure, arrhythmias, cardiogenic shock, pericarditis, sudden cardiac death.
Sources and references: This article is written in accordance with NHS UK, WHO, and Mayo Clinic clinical guidelines. It is reviewed for accuracy by the SymptomSense content team. ICD-10 code: I21. Last reviewed June 2026.