What kind of block is observed in the ECG?
Anonymous Poll
16%
SA node block
26%
Type 1 AVB
24%
Second degree AV block: Mobitz type 1
24%
Second degree AV block: Mobitz type 2
10%
Complete heart block
The ECG demonstrates grouped beats. P-waves precede the QRS complexes with constant but prolonged PR intervals. This indicates a first-degree AV block.
Please note that P-wave is absent during the pause between the grouped beats. This pattern suggests an SA node block, rather than a second-degree AV block, in which a P-wave is present during the pause but is not followed by a QRS complex.
For more advanced users:
The P-P interval progressively shortens prior to the dropped P wave. The duration of the PP interval during the pause is less than twice the length of the shortest PP interval which is observed prior to the pause. This suggests a second-degree, Wenckebach sinoatrial block.
Special thanks to Dr. Salvatore for his expert ECG interpretation and the informative diagram he provided.
Please note that P-wave is absent during the pause between the grouped beats. This pattern suggests an SA node block, rather than a second-degree AV block, in which a P-wave is present during the pause but is not followed by a QRS complex.
For more advanced users:
The P-P interval progressively shortens prior to the dropped P wave. The duration of the PP interval during the pause is less than twice the length of the shortest PP interval which is observed prior to the pause. This suggests a second-degree, Wenckebach sinoatrial block.
Special thanks to Dr. Salvatore for his expert ECG interpretation and the informative diagram he provided.
Based on the provided ECG findings, what is the most likely diagnosis?
Anonymous Poll
12%
Ventricular tachycardia
34%
Atrial fibrillation with LBBB and Ashman phenomena
20%
AVNRT with LBBB and PVCs
34%
Junctional tachycardia with LBBB and PVCs
The ECG shows a repeating pattern of four beat groupings. In the first three beats of each group beat, the QRS complexes are wide and followed by retrograde P waves that come after the QRS, suggesting the beats start near the AV node (junctional tachycardia). The wide QRS complexes are due to underlying Left Bundle Branch Block (LBBB). The fourth beat in each group looks different, comes earlier than expected, and doesn't have a P wave after it, which indicates a Premature Ventricular Contraction (PVC).