Cardiac Anatomy #1
What is a critical component of the circulatory system that is essential for normal vascular, immune and hemostatic system function?
Endothelium
What is the normal (average) amount of pericardial fluid?
~ 20 mL
What is considered the pacemaker of the heart?
SA node
What is the catecholamine of sympathetic stimulation and what is it's effect?
Norepinephrine, increases electrical conductivity and strength of contraction
What are the three types of capillaries?
continuous, sinusoid, fenestrated
What are the four surfaces of the heart?
Diaphragmatic (inferior) surface, anterior surface, right pulmonary surface, left pulmonary surface
What are the partitions of the heart and what do they separate?
Coronary sulcus - separates atria from ventricles; A/P interventricular sulci - separates ventricles
What is the conduction pathway of an electrical impulse in the heart?
SA node - AV node - Bundle of his - left/right bundle branches - purkinje fibers
What nerve provides sensory innervation to the heart?
Phrenic nerve
What two cardiac enzymes are released during myocardial injury?
Troponin T and Troponin I
What structures are included in the middle mediastinum?
Pericardium, heart, origins of the great vessels, nerves and smaller vessels
What are the three layers of blood vessels (list in order from outermost to innermost layer)?
tunica externa, tunica media, tunica intima
What produces the S1 sound of the cardiac cycle?
AV valve closure
What nerve controls parasympathetic activity of the heart?
Vagus nerve
What term refers to the length tension relationship of cardiac muscle?
Frank-Starling law
What are the layers of the heart wall (list from innermost to outermost layer)?
endocardium, myocardium, epicardium
Where to the left and right coronary arteries receive their blood supply?
Aortic sinus of the ascending aorta
What physiologic finding does the P wave represent on an EKG?
Atrial depolarization
What are the vasodilator hormones of the cardiovascular system?
natriuretic peptides (ANP, BNP, CNP)
What is the calculation to determine mean arterial pressure?
MAP = pd + 1/3(Ps-Pd)
What is the name of the interatrial bundle that is considered the main pathway of interatrial conduction?
Bachman's bundle
What nerve innervates the fibrous pericardium?
Phrenic nerve
What is the resting potential of a myocardial cell?
(-) 80-90mV
Cardiac pacemaker cells rely on the inflow of what ion for initiation of action potentials?
Calcium
Arterial chemoreceptors are sensitive to concentrations of what in the blood?
arterial oxygen, arterial carbon dioxide, arterial hydrogen ions