00:01
Hello students, here two questions are asked.
00:02
In the first question they have asked to explain heart rate and stroke volume.
00:08
Heart rate refers to the number of times the heart beats per minute and this is an important indicator of cardiovascular health and they can be measured by using various methods.
00:36
An ecg that is electrocardiogram is a test which records the electrical activity of the heart and it can be used to measure the heart rate by analyzing the time between each heartbeat which are represented by the r to r interval on the ecg and next we will look into the stroke volume.
01:28
Stroke volume refers to the amount of blood that is ejected by the heart with each beat and this can be determined by the difference between the end diastolic volume which is abbreviated as edv and the end systolic volume which is abbreviated as esv of the cardiac cycle.
02:28
Edv is the volume of blood in the ventricles at the end of the diastole while esv is the volume of blood in the ventricles at the end of the systole.
02:41
In the next question they have asked to explain how heart rate can be measured from an ecg and how stroke volume can be calculated using volumes of the cardiac cycle.
02:54
We know that a heartbeat is represented by a series of waves that show how the heart muscle contracts and relaxes over time and in ecg the largest deflection is often the r wave and this represents the main muscle of the heart contracting.
03:44
By identifying the r wave in each beat heart rate can be calculated...