Define cardiac cycle and cardiac output?

Question

Answer

Answer

Cardiac cycle includes all the events associated with one heart beat it's about 0.8 sec in which 0.1 sec - atrial systole and 0.3 sec - ventricular systole and 0.4 sec joint diastole

and cardiac output is volume of blood ejected from each venricle per minute it's about 5 liters per minute

Answer

•Cardiac cycle - The sequential event of heart which is cyclical occured is called cardiac cycle.

•cardiac output - The stroke volume is multiplied by 70-72 cardiac cycle per minute which is equal to 4900 ml. It is called cardiac output.

Answer

Cardiac cycle duration is 0.8 s and is Cardiac output = stroke volume × Heart rate . Cardiac output is generally 5L/ min in a healthy adult...

Answer

Cardiac Cycle:

The cardiac cycle refers to the sequence of events that occur during one complete heartbeat, which involves the contraction (systole) and relaxation (diastole) of the heart chambers. It can be divided into two main stages: systole and diastole.

Systole:
During systole, the heart contracts to pump blood into the arteries. It consists of two phases:

1. Atrial Systole: This phase begins with the contraction of the atria, which forces blood into the ventricles. The atrioventricular (AV) valves are open, allowing blood to flow into the ventricles.

2. Ventricular Systole: In this phase, the ventricles contract, causing the closure of the AV valves and the opening of the semilunar valves. This results in the ejection of blood from the ventricles into the pulmonary artery and aorta.

Diastole:
During diastole, the heart relaxes and fills with blood. It also consists of two phases:

1. Ventricular Diastole: This phase begins with the relaxation of the ventricles. The semilunar valves close, preventing blood from flowing back into the ventricles. The AV valves remain closed initially, but as the atria fill with blood, the pressure causes them to open, allowing blood to flow into the ventricles.

2. Atrial Diastole: In this phase, the atria continue to fill with blood from the veins. The ventricles are in a relaxed state, preparing for the next cardiac cycle.

Cardiac Output:

Cardiac output is the amount of blood pumped by the heart per minute. It is calculated by multiplying the stroke volume (the amount of blood pumped per heartbeat) by the heart rate (the number of heartbeats per minute).

Formula:
Cardiac Output = Stroke Volume × Heart Rate

Cardiac output is an important parameter for assessing the overall function of the cardiovascular system. It reflects the ability of the heart to supply oxygen and nutrients to the body's tissues.

Factors Affecting Cardiac Output:
Several factors can influence cardiac output, including:

1. Heart Rate: An increase in heart rate results in a higher cardiac output, while a decrease in heart rate leads to a lower cardiac output.

2. Stroke Volume: The volume of blood ejected by the heart with each contraction. An increase in stroke volume increases cardiac output, while a decrease in stroke volume decreases cardiac output.

3. Preload: The degree of stretch of the ventricles before contraction. An increase in preload increases stroke volume and subsequently cardiac output.

4. Afterload: The resistance the heart must overcome to eject blood from the ventricles. An increase in afterload reduces stroke volume and cardiac output.

In summary, the cardiac cycle encompasses the systole and diastole phases of the heart's contraction and relaxation. Cardiac output is the amount of blood pumped by the heart per minute and is determined by the stroke volume and heart rate. Understanding these concepts is crucial for evaluating cardiovascular health and function.

Similar NEET Doubts

If the duration of the cardiac cycle is 0.6 sec and the stroke volume is 60ml. Find out the cardiac output?

Cardiac output is 6500ml duration of cardiac cycle is 0.6 what is the stroke volume?

What will be the stroke volume of a person with cardiac output of 6000 ml and 0.8sec for each cardiac cycle? 1)100ml 2)60ml 3)70ml 4)80ml?

how many cardiac cycle occurs during a minute?

Duration of the cardiac cycle?

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