Cardiovascular System Lecture 3 PDF

Cardiovascular system lecture 3 Mo Anatomy CVS ANATOMY Blood supply of the heart Blood supply of the heart...

Cardiovascular system lecture 3 Mo Anatomy CVS ANATOMY Blood supply of the heart Blood supply of the heart A) Coronary arteries Right Coronary Artery Left Coronary Artery Origin Right aortic sinus of the ascending aorta, immediately above the aortic valve Left aortic sinus of the ascending aorta.  Passes in the coronary groove between the right atrium and ventricle.  Passes between the pulmonary trunk and the left auricle  Then passes in the posterior part of the coronary groove between the  Then, it divides into 2 terminals: Course right atrium and ventricle on the diaphragmatic surface of the heart.  anterior interventricular (left anterior descending)  Ends by anastomosing with the circumflex artery.  circumflex artery. 1) Right conus artery: supplies the infundibulum.  Anterior interventricular artery: Gives the following 2) Right atrial branches: supply the right atrium. branches: 3) Right ventricular branches: supply the anterior and inferior surfaces of  Ventricular branches: supply both ventricles (anterior the right ventricle. surface). Branches 4) Marginal artery: runs along the inferior border of the heart to supply  Septal branches: supply the anterior 2/3 of the both surfaces of the right ventricle. interventricular septum.  AV bundle & its branches. DR. ME Page | 1 CVS ANATOMY Blood supply of the heart 5) Posterior interventricular branch (posterior descending): supplies the  Circumflex branch:  posterior surface of both ventricles  curves on the left border of the heart and continues in  the posterior 1/3 of the septum. the posterior of the coronary groove.  AV node in most cases.  Gives the following branches:  SA node in 60% of cases. a) Atrial branches: to the left atrium. b) Ventricular branches: to the left ventricle (the anterior and posterior surfaces). c) Artery to SA node: in 40% of cases. d) Left marginal artery: on the left margin of the heart supplying the left ventricle.  Right coronary dominance: the posterior interventricular artery is a  Left coronary dominance: the posterior interventricular artery arises from the circumflex branch of the left Coronary branch of the right coronary artery. Dominance coronary artery.  Found in 90% of individuals.  Found in 10% of individuals. DR. ME Page | 2 CVS ANATOMY Blood supply of the heart DR. ME Page | 3 CVS ANATOMY Blood supply of the heart B) Veins of the heart A. Venae cordis minimi B. Anterior cardiac veins A number of small veins from the wall of the heart that open directly  3 - 4 veins, which lie on the sternocostal surface of the right ventricle. into the four chambers, mostly into the atria.  Termination: Directly into the anterior wall of right atrium C. Coronary sinus Definition It is the largest vein draining the heart.  Lies in the posterior part of the coronary groove between the back of left atrium above and the diaphragmatic surface of left Site ventricle below accompanying the circumflex artery. Termination  Ends in the right atrium between the IVC opening and the tricuspid orifice Tributaries of the Coronary sinus Tributary Course  Ascends in the anterior interventricular groove accompanied by the anterior interventricular artery. Great Cardiac Vein Curves to the left in the left part of the coronary groove to the back of the heart accompanied by the circumflex artery. Middle Cardiac Vein  Runs in the posterior interventricular groove accompanied by the posterior interventricular artery. Small Cardiac Vein  Runs in the right posterior part of the coronary groove with the right coronary artery. Posterior Vein of Left Ventricle  Runs on the diaphragmatic surface of the left ventricle. Oblique Vein of the Left Atrium  Descends obliquely on the back of the left atrium. DR. ME Page | 4 CVS ANATOMY Blood supply of the heart Nerve supply of the heart  Parasympathetic fibers: from the vagus.  Sympathetic fibers: from the upper 5 thoracic segments of the spinal cord.  Both types of nerves share in the formation of superficial and deep cardiac plexuses. Clinical correlation  Angina pectoris (reduced blood supply due to narrowing of coronaries)  Myocardial infarction (death of part of heart due to cut of blood supply to the affected area). NB: Pain fibers accompany sympathetic nervous system (upper 5)  to dorsal root of spinal cord (in brain it will be interpreted to) T1 to T5 dermatomes cover the chest and medial upper arm and forearm, so myocardial ischemia (heart pain) is felt along left side of chest and inside of left arm. Groove Related Blood Vessels Anterior Interventricular Groove Anterior interventricular artery & great cardiac vein Posterior Interventricular Groove Posterior interventricular artery & middle cardiac vein Right Side of Posterior Part of Coronary Groove Right coronary artery & small cardiac vein Left Side of Posterior Part of Coronary Groove Circumflex artery & coronary sinus Left Side of Anterior Part of Coronary Groove Circumflex artery & great cardiac vein DR. ME Page | 5