ecstatichamster
Member
- Joined
- Nov 21, 2015
- Messages
- 10,530
I understand Dr. Peat to say that the faster heart rate, from say fixing hypothyroid, increases the stroke volume as well as the heart rate.
But this would mean that a higher heart rate increases the blood flow sort of 2 X. More beats, and more volume of blood per beat.
I was telling a medical friend this and she said:
Cardiac output (CO)= stroke volume (SV) X heart rate (RR). Homeostasis determines cardiac output in each individual and it stays relatively constant when not exerting oneself. The two are inversely proportional in order to keep cardiac output relatively constant in resting patients. I did not infer the same thing that you did from this article. When NOT exercising, in the cardiac normal human, volume of heart stroke (SV) does NOT increase along with heart rate. This would raise cardiac output to above homeostatic levels. This only occurs in exercising patients, in which the demand for oxygen causes the cardiac output to increase. otherwise then two values adjust up or down inversely in order to maintain a relatively constant cardiac output during rest. Volume of heart stroke decreases as heart rate increases, in order to keep CO relatively constant in the resting state. This physiological fact, I was taught, in undergrad as well as vet school cardiac physiology lectures.
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So what's right? I am sure Dr. Peat is right, but I don't fully understand.
But this would mean that a higher heart rate increases the blood flow sort of 2 X. More beats, and more volume of blood per beat.
I was telling a medical friend this and she said:
Cardiac output (CO)= stroke volume (SV) X heart rate (RR). Homeostasis determines cardiac output in each individual and it stays relatively constant when not exerting oneself. The two are inversely proportional in order to keep cardiac output relatively constant in resting patients. I did not infer the same thing that you did from this article. When NOT exercising, in the cardiac normal human, volume of heart stroke (SV) does NOT increase along with heart rate. This would raise cardiac output to above homeostatic levels. This only occurs in exercising patients, in which the demand for oxygen causes the cardiac output to increase. otherwise then two values adjust up or down inversely in order to maintain a relatively constant cardiac output during rest. Volume of heart stroke decreases as heart rate increases, in order to keep CO relatively constant in the resting state. This physiological fact, I was taught, in undergrad as well as vet school cardiac physiology lectures.
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So what's right? I am sure Dr. Peat is right, but I don't fully understand.