Puzzle 2004 2 73, A fainting lady with some extrasystoles - Answer: Difference between revisions

 

The ECG shows a sinus rhythm of 100 beats/min. The electrical axis is intermediate (positive QRS complexes in leads I and aVF). The PQ interval is slightly prolonged; the QRS width and morphology are normal. The ST-T segment looks normal and the QT interval is certainly not prolonged. There are two episodes of tachycardia with four broad QRS complexes and two isolated broad complexes with a similar morphology as the initiating beats of the tachycardia. The first two episodes have a changing morphology resembling torsades de pointes (TdP) and pointing to a ventricular origin. However, there are four important differences from what is usually referred to as TdP.