Heart attack

A heart attack, or myocardial infarction (MI), occurs when the blood supply to the heart muscle is partially or completely blocked, usually due to a blood clot (thrombus) forming within a narrowed coronary artery. This blockage deprives the heart of oxygen, leading to damage or death of heart tissue.

A heart attack is a medical emergency – if you suspect a heart attack, call 999 immediately.

1. STEMI (ST-Elevation Myocardial Infarction)

• The most severe type of heart attack caused by a complete blockage of a coronary artery.
• Characterized by ST-segment elevation on an ECG, indicating major heart muscle damage.
• Requires emergency PCI (angioplasty & stenting) or clot-busting medication (thrombolysis).

2. NSTEMI (Non-ST-Elevation Myocardial Infarction)

• A partial artery blockage, leading to heart muscle damage without ST-segment elevation on an ECG.
• Often diagnosed by elevated troponin levels in blood tests.
• Still requires urgent treatment with medications and possibly PCI to prevent worsening.

3. MINOCA (Myocardial Infarction with Non-Obstructive Coronary Arteries)

• Heart attack without major artery blockages, often due to microvascular disease, coronary artery spasms, or spontaneous coronary artery dissection (SCAD).
• More common in women and younger adults.
• Requires specialized treatment focusing on underlying vascular or inflammatory conditions.

The most common cause of a heart attack is coronary heart disease (CHD), where fatty deposits (atherosclerotic plaques) build up inside the coronary arteries. These plaques can rupture, triggering a blood clot that blocks blood flow to the heart muscle.

Other, less common causes include:

• Spontaneous Coronary Artery Dissection (SCAD) – A tear in the coronary artery, disrupting blood flow.
• Coronary Vasospasms (Prinzmetal’s Angina) – Temporary spasms of the coronary arteries, restricting blood supply.
• Microvascular Dysfunction – Blockages in small heart blood vessels rather than major coronary arteries (common in MINOCA).

Risk Factors for a Heart Attack

Modifiable Risk Factors
•       High cholesterol (LDL) – Contributes to atherosclerosis.
•       High blood pressure (hypertension) – Increases strain on arteries.
•       Smoking – Damages blood vessels and promotes plaque formation.
•       Diabetes – Increases risk of silent heart attacks.
•       Obesity & Poor Diet – Leads to metabolic syndrome and heart disease.
•       Physical Inactivity – Raises cardiovascular risk.
•       Excessive Alcohol – Can increase blood pressure and cholesterol.

Non-Modifiable Risk Factors
•       Age – Risk increases with age, particularly in men over 45 and women over 55.
•       Family History – A strong family history of heart disease increases risk.
•       Ethnicity – South Asian, African, and Caribbean populations have a higher risk.

QRISK Score and Coronary Artery Calcium (CAC) Score are used to predict an individual’s 10-year risk of a heart attack.

The symptoms of a heart attack can include:

•       Chest pain or discomfort – A pressure, tightness, or squeezing sensation in the chest.
•       Pain radiating to the jaw, neck, arms, shoulders, or back.
•       Shortness of breath.
•       Cold sweats, nausea, dizziness, or fainting.
•       Unusual fatigue (especially in women and older adults).

Women’s Heart Attacks:

Women often experience atypical symptoms like fatigue, nausea, dizziness, or breathlessness, making diagnosis more challenging.

Diagnosis and Testing
        •       ECG (Electrocardiogram) – Identifies STEMI, NSTEMI, or arrhythmias.
•       Troponin Blood Test – Measures heart damage markers.
•       Coronary Angiography – Detects blockages in the arteries.
•       Cardiac MRI or CT Scan – Provides detailed images of heart function.

Immediate First Aid

• Call 999 immediately – Do not delay medical attention.
• Chew and swallow 300mg aspirin – Helps thin the blood.
• Rest and stay calm – Avoid exertion.
• Perform CPR if unconscious – If the person collapses and is unresponsive, begin chest compressions (100-120 per minute).
  
  

Medications
•       Antiplatelets (Aspirin, Clopidogrel, Ticagrelor) – Prevent blood clots.
•       Beta-blockers – Reduce heart strain.
•       ACE inhibitors / ARBs – Protect the heart and lower blood pressure.
•       Statins – Reduce cholesterol and plaque formation.
•       Nitrates – Help relieve chest pain.

Lifestyle Modifications
•       Diet – Increase fruits, vegetables, whole grains, and reduce saturated fats & salt.
•       Exercise – 150 minutes of moderate activity per week.
•       Quit Smoking – One of the best ways to reduce risk.
•       Manage Stress – Meditation, breathing exercises, and therapy.

Cardiac Rehabilitation
A structured program of exercise, education, and lifestyle support to aid recovery.

Mental Health and Heart Attack Recovery
Many heart attack survivors experience psychological distress, including:
•       Post-Heart Attack Depression & Anxiety
•       Cardiac PTSD (Post-Traumatic Stress Disorder)

Seeking mental health support and cardiac rehab can improve recovery outcomes.

Key Facts

• Responsible for nearly 100,000 hospital admissions per year in the UK.
• Kills over 25,000 people annually in the UK.
• Women are more likely to experience “silent” or atypical heart attacks.

New & Emerging Treatments

Bioresorbable Stents – Dissolve over time, reducing complications.
Stem Cell Therapy – Research on regenerating damaged heart tissue.
Artificial Intelligence (AI) in Early Detection – AI-enhanced ECGs for early diagnosis.