Blood supply of the Heart

1. Blood supply of the Heart Dr. Sama ulHaque Dr Rania Gabr

2. Objectives • Enlist the arteries and veins supplying heart. • Describe the origin and branches of the right and left coronary arteries. • Define coronary artery anastomosis. • Describe the arterial supply of the conducting system of heart. • Discuss the venous drainage and nerve supply of the heart.

3. Arterial supply of Heart • Right coronary artery • Left coronary artery

4. Origin of Coronary Arteries RCA LCA • They arise fromthe initial part of the Ascending Aorta (Aortic Sinuses), immediately above the aortic valve. AA

5. Right Coronary Artery Arises from the anterior aortic sinus of the ascending aorta. Descends in the right atrioventricular groove between the Right Auricle and the Pulmonary trunk. At the inferior border of the heart it continues posteriorly along the atrioventriculargroove . Anastomoses with the left coronary artery in the posterior interventricular groove.

6. Right Coronary Artery

7. Branches of the Right Coronary artery 1- Right Conus artery: For infundibulum and upper part of anterior wall of the right ventricle. 2- Anterior ventricular branches: 2-3 branches supply anterior surface of the right ventricle. Marginal arteryis the largest branch, runs along the lower margin of the sternocostal surface up to the apex. Right conus Anterior ventricular brs

8. 3- Atrial branches; Supply anterior and lateral surfaces of the right atrium One branch supplies posterior surface of both atria: (Artery of the Sinoatrial Node ) Supplies the SAN and both atria In 60% it arises from the Rt coronary, 40% from the Lt coronary 4- Posterior ventricular branches; About 2, supply the diaphragmatic surface of the right ventricle.

9. 5- Posterior interventricular (descending) artery:90% • Runs towards apex in the posterior interventriculargroove. • Supplies the right & left ventricles, including its inferior wall. • Supplies the posterior part of the ventricular septum (Excluding Apex). • Large septal branch Supplies the Atrioventricular Node.

10. (RCA ) Supplies: • Right atrium, • Right ventricle, • Part of Left Atrium, • Left ventricle & Atrioventricular septum. • Most of the conducting system

11. Right Coronary Artery

12. Right Coronary Artery

13. Left Coronary Artery The Larger of the two coronaries. Arises from the left posterior aortic sinusof the ascending aorta. Descends: 1. Between the pulmonary trunk and the left auricle. 2. In the IV groove to the apex of the heart. Divides into two terminal branches: Anterior Interventricular & Circumflexarteries. Supplies the greater part of the left Atrium, left ventricle and ventricular septum.

14. Branches 1- Anterior Interventricular Descends in the anterior interventricular groove to the apex of the heart (in most individuals it passes around the apex to anastomose with terminal branches of the right coronary , in 1\3 it ends at the apex ). It supplies the right and left ventricles and anterior part of ventricular septum Branches 1) Left conusartery for pulmonary conus. 2) Left diagonal artery one of the ventricular branches or may arise from the trunk of left coronary,

15. 2. Circumflex artery: Winds around the left margin of the heart in the atrioventricular groove. 1) Left marginal branch: Supplies the left ventricular margin up to Apex. 2) Anterior and posterior ventricular branches: Supplies the left ventricle. 3) Atrial branches: Supplies the left atrium. 3. Artery of SinoatrialNode (40%)

16. Left Coronary Artery

17. Variations of the Coronary Arteries • Right Dominance: • In (90 %) of population, the Posterior Interventricular artery is a branch of the Right Coronary. • Left Dominance: • In the rest (10%), the Posterior Interventricular artery arises from the Circumflex branch of the Left Coronary A

18. Coronary Anastomosis • In MOST of people, the terminal branches of the right and left coronaries anastomose in the posterior part of the IV groove • However this anastomoses is notlarge enough to provide adequate blood supply in case of coronary occlusion, (Functional End arteries)

19. Arterial supply of the Conducting system of Heart • S-A Node: • Right coronary artery (60%) • Left coronary artery (40%) • A-V Node and A-V Bundle: Right coronary artery • Right Bundle branch: Left coronary artery • Left Bundle branch: Right & Left coronary arteries

20. Venous Drainage of Heart Coronary Sinus • Drains most of the Venous Blood of the heart. • Runs in the coronary sulcus (posterior atrioventricular groove). • Origin : It is the continuation of the Great Cardiac Vein. • Tributaries: • (3) Cardiac Veins: • A. Great. • B. Middle. • C. Small. • Oblique vein of left atrium (vein of Marshall).

21. Termination: • It empties into Right Atrium. • Its opening is inferior & to the left of the IVC opening. • It is guarded by a valve.

22. Veins Draining outside Coronary Sinus • 1. Anterior cardiac veins: • Open directly into the Right Atrium. • 2. Venae Cordis minimie (small cardiac veins): • Open into the heart chambers.

23. Contents of Heart grooves 1. Right atrioventricular groove: Right coronary artery Small cardiac vein 2. Left anterior atrioventricular groove: Left coronary artery 3. Left posterior atrioventricular groove: Coronary sinus 4. Anterior interventricular groove: Anterior interventricular artery Great cardiac vein 5. Posterior interventricular groove: Posterior interventricular artery Middle cardiac vein

24. Cardiac Veins (Sternocostal Surface) Anterior cardiac veins

25. Cardiac Veins (Diaphragmatic Surface)

26. Nerve supply of the Heart Cardiac plexus lies below the arch of Aorta. 1. Sympathetic Supply: Cervical and upper thoracic spinal nerves 2. Parasympathetic Supply: Vagus nerve