Pre Load VS After Load Heart

best describes cardiac afterload

Cardiac afterload is the pressure the ventricles must work against to pump blood out of the heart by opening up through the semilunar valves. So, it's the pressure the ventricles must overcome to open the semilunar valves to push blood out of the heart.

What two factors are used to calculate cardiac output

Cardiac output is calculated by taking the heart rate and multiplying it by stroke volume. CO = HR x SV

A patient with hypovolemic shock is given IV fluids. IV fluids will help _________ cardiac output by:

IV fluids will increase venous return to the heart. This will increase the amount of fluid that will fill the ventricles at the end of diastole...hence increasing preload and increasing cardiac output.

the factors that influence stroke volume:

Preload, afterload, and contractility all have a role with influencing stroke volume.

___________ is the amount of blood pumped by the left ventricle with each beat.

Stroke volume is the amount of blood pumped by the left ventricle with each beat.

What best describes the term cardiac preload

The amount the ventricles stretch at the end of diastole Cardiac preload is the amount the ventricles stretch at the end of diastole (the filling or relaxation phase of the heart).

treatments that would decrease cardiac preload?

The patient has a high systemic vascular resistance...as evidence by the patient's blood blood....there is vasoconstriction and this is resulting in the high blood pressure. Therefore, right now, the cardiac afterload is high because the ventricle must overcome this high pressure in order to pump blood out of the heart. If a vasodilator is given, it will decrease the blood pressure (hence the systemic vascular resistance) and this will decrease the cardiac afterload. The amount of the pressure the ventricle must pump against will decrease (cardiac afterload decrease) because the blood pressure will go down (hence the systemic vascular resistance).

True or False: Pulmonary and systemic vascular resistance both play a role with influencing cardiac afterload.

True. If pulmonary vascular resistance or systemic vascular resistance is high, it will create an increased cardiac afterload. If pulmonary vascular resistance or systemic vascular resistance is low, it will create a decreased cardiac afterload.

conditions that can result in an increased cardiac afterload

Vasoconstriction increases systemic vascular resistance which will increase cardiac afterload. It will increase the pressure the ventricle must pump against to open the semilunar valves to get blood out of the heart. Aortic stenosis creates an outflow of blood obstruction for the ventricle (specifically the left ventricle) and this will increase the pressure the ventricle must pump against to get blood out through the aortic valve. Pulmonary hypertension increases pulmonary vascular resistance which will increase the pressure the right ventricle must overcome to open the pulmonic valve to get blood out of the heart....all of this increase cardiac afterload.