Cardiovascular confusion pairs
36 Cardiovascular topics students commonly mix up on Step 1, each with the fastest separator, a side-by-side comparison, and a free practice question.
- Septic shock vs Cardiogenic shockSeptic shock is low-SVR vasodilation; cardiogenic shock is pump failure with high filling pressures.Video
- Mitral regurgitation vs Mitral stenosisMR: blowing holosystolic apical murmur radiating to the axilla; MS: low-pitched mid-diastolic rumble after an opening snap.Video
- Stable angina vs Acute coronary syndromeStable is predictable demand ischemia; new, worse, or rest pain is ACS until biomarkers and ECG classify it.Video
- Left-sided heart failure vs Right-sided heart failureLeft-sided failure: pulmonary congestion (dyspnea, crackles, S3); right-sided failure: systemic congestion (JVD, edema, ascites).Video
- Aortic stenosis vs Hypertrophic cardiomyopathyAS is fixed obstruction with pulsus parvus et tardus; HCM is dynamic obstruction with brisk/bifid pulse and louder murmur when preload…Video
- Cardiac tamponade vs Tension pneumothoraxTamponade is muffled heart sounds and effusion; tension pneumothorax is absent unilateral breath sounds with hyperresonance.Video
- Restrictive cardiomyopathy vs Constrictive pericarditisRestrictive is stiff myocardium; constrictive is stiff pericardium with exaggerated ventricular interdependence.Video
- Aortic stenosis vs Aortic regurgitationAS is systolic obstruction with carotid radiation; AR is diastolic leak with wide pulse pressure.Video
- Mitral valve prolapse vs Mitral regurgitationMVP is click plus late systolic murmur; MR is holosystolic apical murmur radiating to axilla.Video
- Tricuspid regurgitation vs Pulmonary regurgitationTricuspid regurgitation is holosystolic at the lower left sternal border; pulmonary regurgitation is early diastolic at the left upper…Video
- Dilated cardiomyopathy vs Hypertrophic and restrictive cardiomyopathyDilated is systolic low EF; hypertrophic and restrictive are primarily diastolic filling/obstruction patterns.Video
- Cor pulmonale vs Left heart failureCor pulmonale starts in lung/pulmonary vessels and fails the RV; left HF starts in the LV and congests the lungs.Video
- Stable and unstable angina vs Prinzmetal anginaStable/unstable angina is plaque-demand or ACS pattern; Prinzmetal is vasospasm with transient ST elevation.Video
- NSTEMI vs STEMINSTEMI is troponin positive without ST elevation criteria; STEMI is territorial ST elevation or equivalent occlusion pattern.Video
- Type I myocardial infarction vs Type II myocardial infarctionType I MI: atherothrombotic plaque rupture with coronary thrombus; type II MI: oxygen supply-demand mismatch without plaque rupture.Video
- Acute pericarditis vs Myocardial infarction on ECGPericarditis is diffuse ST elevation plus PR depression; MI is regional ST elevation with reciprocal changes.Video
- Constrictive pericarditis vs Cardiac tamponadeConstrictive pericarditis is chronic rigid shell with Kussmaul/knock; tamponade is pressurized fluid with shock/pulsus paradoxus.Video
- Atrial flutter vs Atrial fibrillationFlutter has organized sawtooth atrial activity; fibrillation has no organized P/flutter waves and is irregularly irregular.Video
- Lower-grade AV block vs High-grade AV blockFirst-degree delays, Wenckebach lengthens then drops, Mobitz II drops without lengthening, third-degree dissociates.Video
- WPW pattern vs Atrial fibrillation with WPWWPW pattern is baseline delta wave; AF with WPW is irregular wide tachycardia where AV nodal blockers can be dangerous.Video
- Torsades de pointes vs Other polymorphic ventricular tachycardiaTorsades is polymorphic VT plus prolonged QT; polymorphic VT with normal QT is not torsades.Video
- Wenckebach vs Mobitz IIWenckebach (Mobitz I): progressive PR lengthening before a dropped beat, usually benign; Mobitz II: fixed PR with a sudden drop, needs…Video
- Patent ductus arteriosus vs Coarctation of the aortaPDA is continuous machinery murmur; coarctation is upper-lower extremity pulse and pressure difference.Video
- Tetralogy of Fallot vs Eisenmenger syndromeTOF is primary cyanotic anatomy; Eisenmenger is late shunt reversal after an initially left-to-right lesion.Video
- Atrial septal defect vs Ventricular septal defectASD: wide fixed split S2; VSD: harsh holosystolic murmur at the lower left sternal border.Video
- Truncus arteriosus vs Tetralogy of Fallot and transpositionTruncus is one trunk; TOF is obstructed RV outflow with VSD; TGA is parallel switched arteries.Video
- Infantile/preductal coarctation vs Adult/postductal coarctationPreductal coarctation presents as ductal-dependent neonatal shock; postductal presents later with arm-leg pressure gradient and collaterals.Video
- Acute infective endocarditis vs Subacute infective endocarditisAcute infective endocarditis is fast, toxic, and destructive; subacute infective endocarditis is slower, constitutional, and usually on…Video
- Sterile endocarditis vs Infective endocarditisSterile vegetations are culture-negative and context-driven; infective vegetations have fever and microbial evidence.
- Acute rheumatic fever vs Rheumatic heart diseaseAcute rheumatic fever is the active post-strep inflammatory syndrome; rheumatic heart disease is chronic valve scarring.Video
- Polyarteritis nodosa vs Microscopic polyangiitisPolyarteritis nodosa is medium-vessel disease that classically spares lungs; microscopic polyangiitis is small-vessel pulmonary-renal…Video
- Buerger disease vs Raynaud phenomenonBuerger disease is tobacco-linked occlusive ischemia with tissue threat; Raynaud phenomenon is episodic reversible vasospasm.Video
- Takayasu arteritis vs Giant cell arteritisBoth are granulomatous large-vessel vasculitides; Takayasu is young pulseless aortic-branch disease, while giant cell arteritis is older…Video
- Kawasaki disease vs IgA vasculitis / polyarteritis nodosaKawasaki is fever plus mucocutaneous coronary-risk disease; IgA vasculitis is purpura-GI-renal disease; PAN is systemic medium-vessel…Video
- Aortic dissection vs Myocardial infarction / pulmonary embolismDissection is chest pain plus aortic/branch-vessel clues; MI is coronary ischemia; PE is pleuritic hypoxemic thromboembolism.Video
- Hypertensive emergency vs Hypertensive urgencyEmergency equals severe BP plus acute organ damage; urgency equals severe BP without acute organ damage.Video
Cardiovascular rapid reviews
Several confusion pairs per video, with chapters for each pair.
Medicine Explained
Plain-language explainers on the physiology behind cardiovascular.
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