CORONARY VASCULATURE DR. NIVIN SHARAF MD LMCC

OBJECTIVES This lecture covers the ILO titled: Enlist the arteries, veins and nerves supplying the heart. By the end of this lecture we will be able to: Define Right/ left or Coronary co dominance Enlist areas of the heart supplied by the right andd left coronary arteries Define the origins of coronary arteries Recognize innervation of the heart

ORIGIN

ORIGIN CONT.

RIGHT CORONARY ARTERY (RCA) Supplies: Right atrium Most of right ventricle Diaphragmatic surface of left ventricle Post 1/3 of iv septum SA node 60% of people AV node 80% of people

LEFT CORONARY ARTERY

LEFT CORONARY ARTERY (LCA) Supplies -Left atrium -- Most of lt ventricle -Part of right ventricle -Most of the interventricular septum 2/3 rds -SAN (40%) -AVN( 20%)

VENOUS DRAINAGE

VENOUS DRAINAGE CONT. The heart is drained by veins that empty in the coronary sinus, partly by small veins that empty in the right atrium Coronary sinus: Main vein of the heart Runs left to right in the coronary groove

CORONARY SINUS

INNERVATION OF THE HEART Autonomic nervous system from superficial and deep Cardiac plexuses Nerve networks lie anterior to the bifurcation of the trachea, posterior to ascending aorta Superior to bifurcation of Pulmonary trunk

INNERVATION OF THE HEART Parasympathetic supply: Presynaptic fibers of the vagus nerves Post synaptic fibers also end in the SA,& AV nodes, and directly on the coronary arteries Stimulation results in  Saving energy between periods of increased demands) Decreased heart rate Reduce the force of heart beats Constrics cornoray arteries

INNERVATION OF THE HEART CON. Sympathetic stimulation  Increases heart rate, and the force of contraction, and inhibits contraction of the coronary arteries”Passively dilates “ Presynaptic fibers with cell bodies in the lateral horn of T1-6 segments of spinal cord Postsynaptic: cervical, and superior thoracic prevertebral ganglia of the sympathetic trunk( end in SA, and AV nodal tissue)

LYMPHATIC TRAINAGE Subepicardial lymphatic plexus Pass to the coronary groove, and follow the coronary arterie End in the inferior tracheobronchial lymphnodes, usually on the right side

REFERENCES Myocardial blood supply Anatomy of the heart Part II CLINICALLY ORIENTED ANATOMY FOURTH EDITION/ KEITH L. MOORE RECOMMENDED READING PAGES