Cardio A&P review Flashcards
Venous blood from IVC and
SVC passively empties into
the ______
right atrium
During diastole (relaxation of the ventricles) blood flows through the right atrium,
through the _____ valve, and into the right ventricle
right atrioventricular
When the right ventricle contracts, venous
blood is pushed through the _____ into the pulmonary artery
pulmonary valve
This contraction provides the pressure
that sustains pulmonary blood flow for
ventilation and diffusion
Right ventricle contraction
Considered the “workhorse”, the _____ sustains the systemic blood pressure.
left ventricle
The serous pericardium is further
divided into two layers
■ Parietal Layer
■ Visceral Layer
Cardiac Cell membranes are fused with each other at _____
the intercalated discs and function as communicating gap junctions between cells
Between the visceral and parietal layers, there is a potential space called the _____
Pericardial Cavity
Two main types of cardiac muscle
fibers exist in the heart
○ Excitatory fibers: conduct electrical
current through the tissue of the heart
○ Contractile fibers
What does it mean that cardiac muscle is a syncytium?
cardiac cells are so
interconnected that when one cell
becomes excited, the action potential
rapidly spreads to all of them
Removal of calcium leads to _____
the relaxation of the muscle (bradycardia)
There is an important difference in the action potentials recorded in cardiac
muscle cells compared to skeletal muscle cells, what is it?
Cardiac action potentials include a Plateau: This plateau in cardiac depolarization causes
ventricular contraction to last as much as 15
times longer than skeletal muscle
contractions from a single action potential.
In cardiac cells, the same rapid sodium and potassium channels still exist. However, the presence of______ is mostly
responsible for the difference in action potential tracings
a special L-Type Calcium Channel
T/F L-Type calcium/sodium channels are faster than voltage gated sodium channels
F- L-Type Calcium Channels (also known as Slow Calcium Channels and
Calcium-Sodium Channels) are found in the cell membrane and open rather
slowly (compared to voltage-gated Sodium channels) and remain open
much longer
The cardiac events that occur from the
beginning of one heartbeat to the beginning
of the next beat = ______
“The Cardiac Cycle.”
The first phase of the cardiac cycle is ______
diastole
Ends with atrial contraction- the “Kick.”
Diastole
The pulmonary and
aortic valves are
made of _____
sturdy cusps (leaflets)
During diastole, the pulmonary and aortic valves are _____
closed (dub)
During systole, the AV valves are _____
closed (lub)
During systole, the pulmonary and aortic valves are _____
open
______ is the single largest killer of all people
in the United States.
Coronary artery atherosclerosis
This allows for entry of LDL
cholesterol into the tunica intima
microinflammation or damage to
the intima of the arterial wall.
The earliest pathologic lesion of atherosclerosis
“fatty streaks” of LDL cholesterol in the tunica media
The presence of serum lipoproteins in the tunica intima triggers the
______
gathering of Monocytes (which become tissue macrophages), which phagocytize the LDL cholesterol, becoming “Foam Cells.”
Plaques, also called Atheromas, characteristically occur in regions of
______
branching and/or marked curvature (velocity and direction change)
What happens when a placque becomes unstable?
The fibrous cap can rupture, exposing thrombogenic contents to the blood. This results in thrombus formation, partial or complete occlusion of the vessel, and further progression and growth of the atheroma
_____ is the main event that causes acute presentation of
coronary syndromes
Plaque rupture
By impairing or obstructing normal blood flow, atherosclerotic buildup causes ______
myocardial ischemia or infarction
When functioning normally, the atrial
contraction (kick) occurs about ____ before the strong ventricular contraction
1/6 of a second