What does negative chronotropy refer to?

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 $24.99Unlock all

Prepare for the Cardiac Electrophysiology Test. Study with interactive quizzes and multiple choice questions. Each question includes helpful hints and detailed explanations. Start your journey to success on your cardiac exam now!

Multiple Choice

What does negative chronotropy refer to?

Explanation:
Negative chronotropy means slowing of the heart rate due to parasympathetic (vagal) influence. When the vagus nerve is activated, acetylcholine acts on M2 receptors in the SA node, opening GIRK channels, hyperpolarizing pacemaker cells, and slowing the slope of phase 4 depolarization. This reduces the firing rate of the SA node, lowering heart rate. The parasympathetic system also slows AV nodal conduction, but chronotropy specifically refers to rate. In contrast, sympathetic activation or catecholamines increase heart rate (positive chronotropy), and there is no change in rate would reflect neutral chronotropy.

Negative chronotropy means slowing of the heart rate due to parasympathetic (vagal) influence. When the vagus nerve is activated, acetylcholine acts on M2 receptors in the SA node, opening GIRK channels, hyperpolarizing pacemaker cells, and slowing the slope of phase 4 depolarization. This reduces the firing rate of the SA node, lowering heart rate. The parasympathetic system also slows AV nodal conduction, but chronotropy specifically refers to rate. In contrast, sympathetic activation or catecholamines increase heart rate (positive chronotropy), and there is no change in rate would reflect neutral chronotropy.

More Multiple Choice Questions
Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy