Cardiac Output Echo Calculator

Formula

To calculate the Cardiac Output (CO):

\[ CO = \frac{\pi \times (LVOTD / 2)^2 \times VTI \times HR}{1000} \]

Where:

CO is the cardiac output (L/min)
LVOTD is the Left Ventricular Outflow Tract Diameter (cm)
VTI is the Velocity Time Integral (cm)
HR is the heart rate (beats per minute)

What is Cardiac Output?

Cardiac output is the volume of blood the heart pumps per minute. It is a critical parameter in assessing cardiac function and is used to diagnose and monitor patients with heart conditions. Cardiac output is determined by the stroke volume (the amount of blood pumped by the left ventricle of the heart in one contraction) and the heart rate (the number of heartbeats per minute).

Example Calculation 1

Given:

LVOT Diameter (LVOTD) = 2 cm
Velocity Time Integral (VTI) = 20 cm
Heart Rate (HR) = 75 beats per minute

Using the formula:

\[ CO = \frac{\pi \times (2 / 2)^2 \times 20 \times 75}{1000} = 4.71 \text{ L/min} \]

The cardiac output is 4.71 L/min.

Example Calculation 2

Given:

LVOT Diameter (LVOTD) = 2.5 cm
Velocity Time Integral (VTI) = 25 cm
Heart Rate (HR) = 80 beats per minute

Using the formula:

\[ CO = \frac{\pi \times (2.5 / 2)^2 \times 25 \times 80}{1000} = 9.82 \text{ L/min} \]

The cardiac output is 9.82 L/min.