What typically results during a PVC in terms of heart contractility?

What typically results during a PVC in terms of heart contractility?

• A. Requires less oxygen
• B. Increases contractility
• C. Decreases contractility
• D. Has no impact

Answer: (C)

During a premature ventricular contraction (PVC), the heart's contractility typically decreases. A PVC is an early heartbeat originating from the ventricles, disrupting the normal rhythm of the heart. This early contraction means that the heart may not have had enough time to fill with blood adequately before it contracts again. As a result, the stroke volume — the amount of blood ejected from the heart with each beat — is often reduced. This decreased stroke volume can lead to a temporary decrease in overall contractility during that specific heartbeat. Moreover, the heart is meant to function in a coordinated manner, and any early or abnormal contractions can impair the effective pumping action of the heart. While the heart tries to compensate in subsequent beats, the immediate effect of a PVC is a disruption in the normal contractile cycle, leading to decreased efficiency in pumping blood.

During a premature ventricular contraction (PVC), the heart's contractility typically decreases. A PVC is an early heartbeat originating from the ventricles, disrupting the normal rhythm of the heart. This early contraction means that the heart may not have had enough time to fill with blood adequately before it contracts again. As a result, the stroke volume — the amount of blood ejected from the heart with each beat — is often reduced. This decreased stroke volume can lead to a temporary decrease in overall contractility during that specific heartbeat.

Moreover, the heart is meant to function in a coordinated manner, and any early or abnormal contractions can impair the effective pumping action of the heart. While the heart tries to compensate in subsequent beats, the immediate effect of a PVC is a disruption in the normal contractile cycle, leading to decreased efficiency in pumping blood.