Blood supply to cardiac conduction system

Schematic diagram of blood supply to cardiac conduction system. The first septal branch of the left anterior descending (LAD) coronary artery supplies a critical portion of the interventricular conduction system (red oval). AV, atrioventricular; marginal a., marginal artery; PDA, posterior descending artery; RCA, right coronary artery; SA, sinoatrial. Reproduced, with permission, from Harthorne JW, Pohost. GM, Electrical therapy of cardiac dysrhythmias. In Levine, HJ (ed) Clinical Cardiovascular Physiology, New York, Grune and Stratton: 1976. pp. 853–882

Blood Supply to Bundle of Branches

LBBB RBBB

Anterosuperior fascicle Posteromedial fascicle

Both LAD and RCA 50% By septal

branch of LAD and AV node branch of RCA

Other 50% by only LAD

50% Only by the AV nodal branch of RCA(Kugel’s artery)

Other 50% by AV nodal branches of RCA

Septal branches of LAD

Both LAD and RCA50% By septal branch of LAD and AV node branch of RCAOther 50% by only LAD

Simplification is the finest art