Question

Based on the provided ECG description (Third Degree Heart Block), which of the following statements is correct?

A) The P wave is present, but there are no QRS complexes following the P waves, indicating a complete block of electrical signals between the atria and ventricles. The ventricles are pacing at a rate of 40 beats per minute, and the atria are pacing at a rate of 110 beats per minute.

B) The P wave is absent, and there are wide complex QRS complexes indicating a potential issue with ventricular depolarization. The rate is regular at 40 beats per minute.

C) The PR interval is unable to be determined, indicating a potential conduction abnormality between the atria and ventricles. The rate is regular at 110 beats per minute.

D) The P wave is present, and there are narrow complex QRS complexes following the P waves, suggesting normal atrioventricular conduction despite the block. The rate is regular at 40 beats per minute.

Answer 1

The correct statement for a Third Degree Heart Block ECG is that P waves are present without corresponding QRS complexes, with separate atrial and ventricular pacing indicating complete atrioventricular dissociation.

Step-by-step explanation:

Based on the description of a Third Degree Heart Block on an ECG, the correct statement is A) The P wave is present, but there are no QRS complexes following the P waves, indicating a complete block of electrical signals between the atria and ventricles. The ventricles are pacing at a rate of 40 beats per minute, and the atria are pacing at a rate of 110 beats per minute. This is because in Third Degree Heart Block, there is no correlation between atrial activity (the P wave) and ventricular activity (the QRS complex), which means that the P waves and QRS complexes are dissociated, with ventricles typically pacing at a slower rate due to the AV node acting as a secondary pacemaker.