In the context of cardiac action potentials, what is a pulse deficit?

• A. The difference between the apical and radial pulse rates.
• B. The reduction in heart rate during deep inspiration.
• C. The difference in blood pressure readings between the left and right arms.
• D. The time delay between the P wave and the QRS complex on an ECG.

Answer: (A)

Verified step by step guidance

1. Understand the concept of a pulse deficit: It refers to the difference between the apical pulse (heart rate measured at the heart) and the radial pulse (heart rate measured at the wrist).
2. Recognize that a pulse deficit occurs when the heart's contractions are not all strong enough to create a palpable pulse at the radial artery.
3. Consider the physiological implications: A pulse deficit can indicate that not all heartbeats are effectively pumping blood into the systemic circulation.
4. Differentiate between the options given: The pulse deficit specifically refers to the difference between apical and radial pulse rates, not blood pressure differences or ECG time delays.
5. Relate the concept to clinical practice: A pulse deficit can be an important diagnostic tool in identifying conditions like atrial fibrillation, where irregular heartbeats may not always produce a palpable pulse.