Heart Flashcards
Epicardium
The parietal layer that reflects back to cover the external surface of the heart
Where is the heart
In the Medial cavity of the thorax flanked laterally by the lungs, posterior to the sternum
Apex
The pointed portion that extends slightly to the left side of body
Base
Where the great vessels emerge, under second rib and towards right shoulder
Myocardium
The walls of the heart made from cardiac muscle
Right and left atrium (atria)
Receiving chambers for blood that’s entering the heart by the great veins
Auricles
A small ear like extension in the atriums that increase it’s volume
Right and left ventricles
Pumps that eject blood into the arteries and keep it flowing around the body (right goes to lungs & left returns to body)
Endocardium
Thin serous endothelium that lines the inside of the ventricles
(Over the myocardium)
Interatrial septum
The wall that seperates the Arita
Inter-ventricular septum
The wall that separates the ventricles
Strength of walls
Artial- not so strong, gravity flows the blood down
Right ventricle- moderately muscular, to lungs & left atrium
Left ventricle- 2-4 times thicker than the right, pumps blood through body
Superior and inferior vena cava
Drops off oxygen poor blood into right atrium
Pulmonary Veins
Four veins deliver oxygen rich blood to the left atrium from the lungs
Pulmonary trunk
Routes the blood to the lungs to be oxygenated
Aorta
Flows blood to the rest of the body
Bicuspid valves
Two flaps of endocardium where blood passes through from left atrium
Tricuspid valve
3 flaps of endocardium that flow from right atrium
Atrioventricular valves
Pathways that lead from the atria to the ventricles
Chordae tendineae
Cords connected to papillary muscles that hold the cusps down
Papillary muscle
Prevent the AV valves from flipping open
Diastole
When a chamber is relaxed
Systole
When a chamber contracts
Semilunar valves
Controls blood flow from ventricles to great arteries
Pulmonary- opens to right ventricle
Aortic- opens to left ventricle
Brachiocelphalic artery
Right side of heart on top of aortic arch
Ligamentum arteriosum
Connects aorta with left pulmonary artery
Coronary arteries
Left- circumflex branch(blood to left atrium &left posterior ventricle wall)
Anterior ventricular branch(blood to ventricles)
Right- right marginal branch (blood to lateral sides of right atrium/ventricle)
Posterior interventricular branch (blood to posterior walls of ventricles and back portion of interventricular septum)
Sinus rhythm
Normal heartbeat
PVC (premature ventricular contraction)
drugs
Stimuli that causes the heart to contract before the SA Node
Ectopic Focus
region of spontaneous firing (not SA node)
Arrhythmia
Any abnormal cardiac rhythm
Heart block
Failure of any part of the cardiac conduction system #BadSignal
Pacemaker potential
A drift upward, gradual depolarization
•Quiescent period
–all chambers relaxed
–AV valves open and blood flowing into ventricles
•Cardiac Output
Heart Rate x Stroke Volume
