Cardiovascular System
The cardiovascular domain tests ischemic heart disease, heart failure, arrhythmias, valvular disease, hypertension, and lipid disorders, with emphasis on acute stabilization and guideline-directed long-term therapy.
Core rules
- Acute chest pain: obtain a 12-lead ECG within 10 minutes. ST-elevation myocardial infarction (STEMI) needs immediate reperfusion, preferably primary PCI within 120 minutes. Non-STEMI with positive troponin gets aspirin, a P2Y12 inhibitor, anticoagulation, and risk-stratified invasive evaluation.
- Heart failure with reduced ejection fraction (HFrEF) uses four mortality-reducing pillars: ARNI or ACE inhibitor/ARB, evidence-based beta blocker, mineralocorticoid receptor antagonist, and SGLT2 inhibitor. Diuretics treat congestion but do not improve survival.
- Atrial fibrillation: estimate stroke risk with CHA2DS2-VASc. Anticoagulate when the score is at least 2 in men or 3 in women; consider it at 1 and 2, respectively. Rate control with a beta blocker or nondihydropyridine calcium channel blocker.
- Hypertension: confirm with repeated measurements. Start two agents for stage 2 hypertension or high cardiovascular risk.
Worked example
A 68-year-old man has 30 minutes of exertional substernal pressure. ECG shows no ST elevation; high-sensitivity troponin is elevated. This is NSTEMI. Give aspirin, a P2Y12 inhibitor, anticoagulation, and anti-ischemic therapy, then risk-stratify for early invasive angiography. Fibrinolytics are not indicated because there is no ST elevation.
Traps
- Giving nitroglycerin before ECG in possible inferior MI with right ventricular involvement.
- Missing aortic dissection when pain is tearing and pulses or blood pressures differ.
- Using NSAIDs in HFrEF or CKD.
- Treating a single elevated blood pressure reading without confirmation.