Question

Scenario: A patient presents a heart rate higher than the normal range at rest because of tachycardia.

What physiological factors are needed to compensate for the high heart rate? (4 pts)

Answer 1

The physiological factor need to compensate for high rare

1. the heart rate is under the sympathetic and parasympathetic nervous system.
2. The sympathetic autonomous nervous system secretes noradrenaline at their postsynaptic nerve fiber.
3. This is increases the heart rate
4. Whereas, the parasympathetic nerve secrete acetyl choline.
5. The parasympathetic nerve decrease the heart rate/
6. when the heartbeat increase, the sympathetic nervous system influence reduces.
7. The influence of the parasympathetic nervous system is increased on the heart
8. This reduces the heart rate
9. When the heart rate increase following cardiac parameters changes:
   1. Cardiac output = heart rate x stroke volume
   2. Stroke volume is the amount of blood expelled in each contraction.
   3. As the heart rate increase, the stroke volume reduces.
   4. Cardiac output can be normal or low.
   5. There will be reduction in the end-diastolic volume.