Chapter 19 Part 2 Flashcards
surface arteries of the heart that generally follow the sulci
Epicardial coronary arteries
branch of the left coronary artery that follows coronary sulcus
Circumflex artery
major branch of the left coronary artery that follows the anterior interventricular sulcus
Interventricular arteries
supply blood to the myocardium and other components of the heart
Coronary arteries
area where vessels unite to form interconnections that normally allow blood to circulate to a region even if there may be partial blockage in another branch
Anastomosis
Is anastomosis considered dangerous in coronary arteries?
Yes; coronary artery blockage often results in death of the cells (myocardial infarction) supplied by the particular vessel
results from a lack of blood flow (ischemia) and oxygen (hypoxia) to a region of the heart, resulting in death of the cardiac muscle cells
Myocardial infarction
known vasodilator, and endothelium-derived releasing factor, which also relaxes the smooth muscle in the tunica media of coronary vessels
Nitroglycerine
Dissolves blood clots during MIs
Streptokinase
Anticoagulant used during MIs
Heparin
ability of cardiac muscle to initiate its own electrical impulse that triggers the mechanical contraction that pumps blood at a fixed pace without nervous or endocrine control
Autorhythmicity
bulk of the cardiac muscle cells in the atria and ventricles that conduct impulses and contract to propel blood
Myocardial contractile cells
specialized cells that transmit electrical impulses throughout the heart and trigger contraction by the myocardial contractile cells
Myocardial conducting cells
helps support the synchronized contraction of the muscle
Intercalated discs
known as the pacemaker, a specialized clump of myocardial conducting cells that has the highest inherent rate of depolarization that then spreads throughout the heart
SA Node
receives the impulse from the SA node, pauses, and then transmits it into specialized conducting cells within the interventricular septum
AV node
group of specialized myocardial conductile cells that transmit the impulse from the AV node through the interventricular septum
AV Bundle
specialized myocardial conductile cells that arise from the bifurcation of the atrioventricular bundle and pass through the interventricular septum
AV bundle branches
specialized myocardial conduction fibers that arise from the bundle branches and spread the impulse to the myocardial contraction fibers of the ventricles
Purkinje fibers
surface recording of the electrical activity of the heart that can be used for diagnosis of irregular heart function
Electrocardiogram