Sympathetic activation is an example of which chronotropic effect on heart rate?

Unlock all questions

This demo includes only 20 questions. Upgrade to access hundreds of questions, flashcards, exam simulations, and disable ads.

Full question bankExam simulationsFlashcards
From $9.99Unlock all

Prepare for the Cardiac Electrophysiology Test. Enhance your knowledge with flashcards and multiple-choice questions, each supplemented with explanations and hints. Gear up for success on your exam!

Multiple Choice

Sympathetic activation is an example of which chronotropic effect on heart rate?

Explanation:
Sympathetic activation increases heart rate, which is a positive chronotropic effect. Norepinephrine released onto beta-1 receptors in the SA node raises cAMP, activating PKA. This enhances the funny current (I_f) and L-type calcium current, making the diastolic depolarization steeper and speeding up SA nodal firing (and AV nodal conduction). The result is a faster heart rate. The term “inotropic chronotropic” isn’t appropriate here, since inotropic refers to contractility, not rate.

Sympathetic activation increases heart rate, which is a positive chronotropic effect. Norepinephrine released onto beta-1 receptors in the SA node raises cAMP, activating PKA. This enhances the funny current (I_f) and L-type calcium current, making the diastolic depolarization steeper and speeding up SA nodal firing (and AV nodal conduction). The result is a faster heart rate. The term “inotropic chronotropic” isn’t appropriate here, since inotropic refers to contractility, not rate.

More Multiple Choice Questions
Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy