# What is stroke volume and how is it calculated?

## What is stroke volume and how is it calculated?

Stroke volume is the amount of blood ejected from the ventricle with each cardiac cycle. It can be readily calculated by subtracting the end-systolic volume from the end-diastolic volume. Multiplying the stroke volume by the heart rate yields the cardiac output, typically reported in liters per minute.

Is cardiac output the same in both ventricles?

Cardiac output is calculated by multiplying the heart rate and the stroke volume. Cardiac output is the amount of blood pumped by the left ventricle–not the total amount pumped by both ventricles. However, the amount of blood within the left and right ventricles is almost equal, approximately 70 to 75 mL.

### What is the normal range for stroke volume?

Normal Hemodynamic ParametersParameterEquationNormal RangeCardiac Output (CO)HR x SV/10004.0 – 8.0 l/minCardiac Index (CI)CO/BSA2.5 – 4.0 l/min/m2Stroke Volume (SV)CO/HR x 100060 – 100 ml/beatStroke Volume Index (SVI)CI/HR x 100033 – 47 ml/m2/beat19

What is normal end diastolic volume?

For an average-sized man, the end-diastolic volume is 120 milliliters of blood and the end-systolic volume is 50 milliliters of blood. This means the average stroke volume for a healthy male is usually about 70 milliliters of blood per beat. Total blood volume also affects this number.

#### What happens when end diastolic volume increases?

Preload. At all ages, ventricular output depends on end-diastolic volume. An increase in stroke volume or cardiac output occurs when end-diastolic volume is increased (the Frank-Starling relation).

How do you reduce end diastolic volume?

During moderate, upright, whole body exercise (e.g., running, bicycling) increased venous return to the heart by the muscle and respiratory pump systems generally causes a small increase in end-diastolic volume (shown in figure); however, if heart rate increases to very high rates, reduced diastolic filling time can …

## What is the end diastolic pressure?

The volume of blood in the left ventricle at the end of ventricular filling is called the end-diastolic volume (EDV), which is about 120 mL in the adult human. The corresponding pressure, the end-diastolic pressure (EDP), is about 4–7 mmHg.

What is the number one cause of diastolic dysfunction?

HYPERTENSION. Chronic hypertension is the most common cause of diastolic dysfunction and failure. It leads to left ventricular hypertrophy and increased connective tissue content, both of which decrease cardiac compliance.

### What increases end diastolic pressure?

A reduction in ventricular compliance, as occurs in ventricular hypertrophy, increases the slope of the ventricular end-diastolic pressure-volume relationship (EDPVR) and results in less ventricular filling (decreased end-diastolic volume) and a greater end-diastolic pressure (elevated pulmonary capillary wedge …

What is the normal range for left ventricular end diastolic pressure?

In patients with normal left ventricular function, the EDPs in the left ventricle and pulmonary artery were equal (range 5 to 12 mm Hg; average 8 mm Hg; maximum difference ± 4 mm Hg).

#### What if the pulse pressure is high?

This can be due to high blood pressure or atherosclerosis, fatty deposits that build up on your arteries. Additionally, iron deficiency anemia and hyperthyroidism can lead to an increase in pulse pressure. A high pulse pressure is often associated with increased risk of heart attack or stroke, particularly in men.

Is SVR and afterload the same thing?

Afterload, also known as the systemic vascular resistance (SVR), is the amount of resistance the heart must overcome to open the aortic valve and push the blood volume out into the systemic circulation. If you think about the balloon analogy, afterload is represented by the knot at the end of the balloon.