MI — the plain-language one-pager.

What is a Heart Attack?Diagnosis

A heart attack (myocardial infarction, MI) happens when blood flow to part of the heart muscle is blocked — usually by a clot forming on a ruptured cholesterol plaque inside a coronary artery. Without oxygen, that part of the heart muscle starts to die within minutes. Time is muscle. The faster the artery is reopened (with clot-busting medication or, ideally, an emergency catheterization with a stent), the more heart muscle survives, the better the heart pumps long-term, and the lower the risk of heart failure or arrest.

• Two main types — STEMI (a fully blocked artery, ST-elevation on ECG, needs the cath lab fast — door-to-balloon under 90 minutes) and NSTEMI (partial block, also serious, treated with medication + cath in days). Both raise the risk of arrhythmia, heart failure, and a second event.
• Classic warning signs: chest pressure, tightness, squeezing, or burning lasting more than a few minutes; pain spreading to the arm, jaw, neck, back, or stomach; shortness of breath; cold sweat; nausea; lightheadedness; unusual fatigue. Women, older adults, and people with diabetes often present with subtler signs — fatigue, shortness of breath, or "indigestion."
• Top modifiable risk factors: high LDL cholesterol, high blood pressure, smoking, diabetes, obesity, sedentary lifestyle, chronic stress, and untreated sleep apnea. Top non-modifiable: age, family history of early heart disease, prior heart attack, prior CAD diagnosis.
• If you've had a heart attack, the program is about preventing the next one — secondary prevention with statins, antiplatelets, beta-blockers, ACE inhibitors, and cardiac rehab cuts the risk of another event by ~25-40%. The first 12 weeks are the most leveraged.

If you suspect a heart attack — every minute mattersAct now

Most heart attack deaths happen in the first hour, before the person reaches the hospital. The deciding factor is how fast the call to 911 happens. Door-to-balloon under 90 minutes saves heart muscle. Door-to-call is the part you control.

• Call 911 — do not drive. EMS can start treatment, run an ECG en route, alert the cath lab, and get you to a STEMI-capable hospital. Driving yourself or being driven adds dangerous minutes and risks an arrest in transit.
• Chew an aspirin (325 mg or 4 baby) if not allergic and not actively bleeding — only if EMS or your team has told you it is part of your plan, or if 911 dispatcher advises it. Do not delay calling 911 to find one.
• Sit down, stay calm, breathe. Loosen tight clothing. Tell EMS your meds, allergies, and known cardiac history.
• If the person collapses and stops breathing normally → start hands-only CPR + send for an AED. A heart attack can trigger Sudden Cardiac Arrest. CPR doubles or triples survival. The skills are in the FFH Skills Lab.

Half of MI patients wait more than 2 hours before calling. The biggest gain in modern cardiology is on the patient side of the door.

Your daily Force FieldLive It

• Take your secondary-prevention meds every day — high-intensity statin, antiplatelet (aspirin + sometimes a P2Y12 like clopidogrel/ticagrelor), beta-blocker, and ACE inhibitor or ARB if prescribed. Missing doses raises the risk of a second event.
• Show up to cardiac rehab — every single session. Cardiac rehab cuts mortality ~25%. The first 12 weeks are the most leveraged of your life.
• BP target generally <130/80, A1C <7% if you have diabetes, LDL well under 70 mg/dL after MI. Your team will dial in your numbers.
• No tobacco, no vaping, no second-hand smoke — quitting at any age cuts your second-MI risk dramatically.
• Mediterranean / DASH eating, less ultra-processed food, less sodium, more vegetables / fruit / fish / olive oil / nuts.
• 150+ minutes/week moderate activity as cleared by your team — cardiac rehab teaches your safe zone.
• Sleep, stress, mental health, sleep apnea — depression after MI is common and itself raises the risk of a second event. Treat it. Untreated OSA quadruples risk.
• Train your household in CPR + AED — the person most likely to save you is the one in your home. (See Skills Lab CPR + AED rubrics.)

Red flags — call nowAction

• Call your clinic the same day for: new chest discomfort with exertion that goes away with rest (stable angina worth evaluating); a missed dose of antiplatelet or statin; medication side effects (muscle aches, bleeding, GI symptoms).
• Bring up at next visit: any change in exercise tolerance, lipid follow-up timing, BP log review, smoking-cessation support, depression screening, sleep concerns.