How does the amplitude of complexes in torsades de pointes change?

How does the amplitude of complexes in torsades de pointes change?

• A. It remains constant
• B. It gradually increases and then decreases
• C. It decreases sharply
• D. It shows no pattern

Answer: (B)

In torsades de pointes, the amplitude of the complexes changes in a distinct pattern where it gradually increases and then decreases, leading to a characteristic twisting appearance of the QRS complexes around the isoelectric line. This phenomenon is primarily due to the cyclical nature of the arrhythmia, which is often related to altered repolarization and can be triggered by factors such as long QT intervals.

As the complexes progress, there is a building up of amplitude followed by a decline, giving the visual impression of a "twisting" effect. This variability in amplitude results from the dynamic alterations in the electrical activity and repolarization phases occurring within the myocardium. Recognizing this pattern is crucial for identifying torsades de pointes on an EKG, distinguishing it from other arrhythmias that may not exhibit the same amplitude fluctuations.