Cardiology
Core concepts
Ischaemic heart disease dominates. Know STEMI criteria (ST elevation ≥1 mm in two contiguous limb leads, ≥2 mm in V2–V3 in men, or new LBBB with ischaemic symptoms), the role of high-sensitivity troponin in NSTE-ACS, and the time-critical nature of primary PCI. Heart failure separates into HFrEF (EF <40%), with four prognostic drug classes - ACE inhibitor/ARNI, beta-blocker, mineralocorticoid antagonist, SGLT2 inhibitor - and HFpEF, where diuretics and comorbidity control dominate. Learn the murmurs: aortic stenosis (ejection systolic, radiates to carotids, slow-rising pulse, narrow pulse pressure), mitral regurgitation (pansystolic to axilla), mitral stenosis (mid-diastolic with opening snap), aortic regurgitation (early diastolic, collapsing pulse), and hypertrophic cardiomyopathy (ejection systolic that increases with Valsalva and standing). Arrhythmias: rate control and anticoagulation in AF by CHA2DS2-VASc; avoid AV nodal blockers in pre-excited AF (WPW) - use procainamide or electrical cardioversion. Pericarditis gives saddle-shaped ST elevation with PR depression and pleuritic pain; tamponade gives Beck's triad and pulsus paradoxus.
Traps
Confusing Mobitz I (benign, worsens with carotid massage) with Mobitz II (progresses to complete heart block, needs pacing). Forgetting right ventricular infarction in inferior STEMI - hypotension after nitrates. Calling any ST elevation pericarditis when reciprocal depression suggests ischaemia.
Rule of thumb
Chest pain with ST elevation in II, III and aVF is an inferior STEMI: check V1–V3 for reciprocal depression (posterior extension), auscultate for a new murmur, give aspirin and arrange PCI; avoid nitrates and watch for bradycardia.