Blood Pressure
These three factors control stroke volume: preload (influenced by blood volume), contractility, and this component, which increases when there are more red blood cells in the blood
afterload?
This is the total time of one complete cardiac cycle, including all four phases between systole and diastole.
0.8 seconds?
This node initiates the heart’s action potential and is known as the heart’s pacemaker
the SA node
During Phase 0 of the contractile cell action potential, this ion rapidly enters the cell, causing depolarization from –90 to +20 mV.
What is sodium (Na+
This term describes the study of the forces influencing blood circulation and is essential for understanding cardiovascular management in critical care.
What is hemodynamics?
This term refers to the amount of blood ejected by the ventricles with each heartbeat and is influenced by preload, contractility, and afterload.
stroke volume?
These two valves open to allow 70–80% of blood to flow passively into the ventricles without contraction, due to higher atrial pressure.
bicuspid and tricuspid
These cells are non-contractile, generate automaticity, and set the rhythm of the heart.
What are nodal cells?
In Phase 2, the plateau stage, calcium binds to this protein, causing tropomyosin to shift and exposing myosin binding sites on actin filaments
What is troponin?
This port on the pulmonary artery catheter is used for infusing fluids and medications and terminates in the inferior vena cava or right atrium.
What is the white lumen (proximal infusion port)?
This equation expresses blood pressure as the product of cardiac output and total peripheral resistance.
What is BP
During ventricular diastole, these valves remain shut because the pressure in the aorta and pulmonary trunk is higher than in the ventricles.
semilunar valves
After leaving the SA node, the excitation signal travels to this node, where it is delayed by 0.1 seconds to allow atrial contraction.
What is the AV node?
Unlike contractile cells, these cells do not have a resting potential
What are nodal cells?
The normal systolic pressure range for this heart chamber is 15–25 mmHg, while its diastolic pressure ranges from 0–8 mmHg.
What is the right ventricle?
This formula calculates cardiac output, a key determinant of blood pressure.
What is heart rate multiplied by stroke volume?
This sound marks the onset of ventricular contraction during the isovolumetric contraction phase.
What is the "lub" sound?
These specialized structures connect nodal cells to contractile cells, allowing ions to flow freely and enabling action potential transmission.
What are gap junctions?
During Phase 3 of the contractile cell action potential, only this ion is being pumped out of the cell, causing repolarization.
What is potassium (K+)
This device allows for direct, simultaneous measurement of pressures in the right atrium, right ventricle, and left atrium, and is used to manage conditions like hypovolemia and ventricular failure.
What is the pulmonary artery catheter (PAC)?
According to Poiselle’s equation, these three factors determine total peripheral resistance in blood vessels.
viscosity, length, and radius?
At the end of systole, this term describes the blood left in the ventricles after contraction.
end systolic volume?
Name two proteins found in contractile cells that are essential for muscle contraction
What are actin and myosin? (Also acceptable: troponin, tropomyosin)
After the Bundle of His, the electrical impulse travels down these branches to reach the myocardium and then the Purkinje fibers, triggering contraction
What are the left and right bundle branches
Insertion of a pulmonary artery catheter is contraindicated in patients with this conduction abnormality, as it may cause a transient right bundle branch block and potentially lead to complete heart block.
What is left bundle branch block?