Of the types of damage resulting from a myocardial infarction, which is most likely to cause the greatest increase in the Q-T interval?
A) Infarction in the AV node
B) Left bundle branch block
C) Infarction affecting the SA node
D) Tachycardia
E) Ectopic focus

Question

Quizplus · Accepted Answer

Left bundle branch block (LBBB) can significantly prolong the Q-T interval because it delays the depolarization and repolarization of the left ventricle, which is a major component of the Q-T interval on the ECG. This delay in electrical activity can lead to a noticeable increase in the Q-T interval duration.

Of the Types of Damage Resulting from a Myocardial Infarction