Coronary Blood Supply to the Heart*



Artery

Percentage of Time from RCA or LAD

Area Perfused

Left Main (MLCA)
98% present
Entire LV, LA except the posterior portion of IV septum and adjacent area when PD is branch of RCA
Left Anterior Descending (LAD) 98% from MLCA Anterior 2/3 of IV septum, anterior portion of LV, whole apex
First Diagonal(D1) 100% off LCA High lateral wall of LV
Second Diagonal(D2) 100% off LCA Lower lateral aspect of LV free wall
First Septal (S1) 99.8% off LCA Superior and anterior portion of IV septum
Minor Septals (S) 100% off LCA Inferior and anterior 1/3 of septum
Interventricular (Ramus interventricularis) 100% off LCA Anterior aspect of apex
Circumflex (Cx) 97% off LCA, separate ostisum in 2%, off RCA 1% Obtuse margin of heart and its entire posterior wall, LA, post-IV septum if PD is off Cx
Obtuse Marginal (OM) 97% off LCA Obtuse margin of heart, adjacent posterior LV
Posterolateral (PL) 80% off LCA, 20% off RCA Posterior and diaphragmatic LV wall
Posterior Descending (PD) 18% off LCA, 82% off RCA, 4% RCA and Cx Posterior IV septum and diaphragmatic LV
Right Coronary Artery (RCA) 84% around the crux RA and part of LA, RV, posterosuperior IV septum, SN, and AV node
Acute Marginal (AM) 100% off RCA Inferior and diaphragmatic surface of RV
Posterior Descending (PD) 82% off RCA, 18% off LCA, 4% off RCA and Cx Posterior and diaphragmatic area of septum
Conus Branch (CB) 60% off RCA, 40% as a separate vessel off RCA ostium Outflow tract of RV
Sinus node (SN) 59% off RCA, 39% off Cx, 2% off Cx and RCA RA, LA, SN
Right Ventricular Branch (RV) 100% off RCA Right Ventricle
Atrial Branch (A) 100 % off RCA Right Atrium


* Source: Braunwald, E. Heart Disease, A Textbook of Cardiovascular Medicine, 5th Ed. W.B. Saunders Company, Philadelphia, 1980.

| Back to Classroom |