Cardiac Anatomy and Physiology
Start with the flow of blood and the structures it passes through: venae cavae → right atrium → tricuspid valve → right ventricle → pulmonary valve → pulmonary artery → lungs → pulmonary veins → left atrium → mitral valve → left ventricle → aortic valve → aorta. Candidates must know the chambers, the four valves and their cusps, the great vessels, and the coronary circulation (right and left coronary arteries arising from the aortic root; left main dividing into LAD and circumflex). Understand the conduction pathway - SA node, AV node, bundle of His, bundle branches, Purkinje fibers - and which structure is the normal pacemaker.
Physiology questions test pressure–volume relationships: systole versus diastole, the meaning of preload, afterload, and contractility, and why the left ventricle is thicker-walled than the right. Know normal resting values (heart rate, stroke volume, cardiac output roughly 4–8 L/min, ejection fraction) and how they change with exercise.
Traps: confusing the tricuspid (right) with the mitral (left) valve; reversing pulmonary artery and pulmonary vein oxygen content; assuming the AV node is the primary pacemaker; and mixing up systole (ventricular contraction, semilunar valves open) with diastole. Another common trap is attributing coronary perfusion entirely to systole - most left ventricular filling occurs in diastole.
Rule of thumb: "Right side = deoxygenated, low pressure; left side = oxygenated, high pressure." If a question describes a valve between an atrium and a ventricle, it is an atrioventricular valve (tricuspid or mitral); if it sits in an outflow tract, it is semilunar (pulmonary or aortic).