Author + information
- Received October 5, 2012
- Accepted October 9, 2012
- Published online April 30, 2013.
- Kelvin C.K. Wong, MB BChir,
- Intisar H. Mirza, PhD,
- Vishal Nathwani, MB ChB, BSc and
- Yaver Bashir, BMBCh, DM
A 56-year-old man presented with a 4-month history of exercise-induced palpitations and pre-syncope. Resting electrocardiogram and echocardiogram were normal. Treadmill testing provoked a polymorphic, broad complex tachycardia (A). During recovery, atrial flutter with 2:1 atrioventricular (AV) conduction was noted before reverting to sinus rhythm spontaneously. Treadmill testing was repeated with real-time recording of atrial electrograms via an active-fixation pacing lead placed in right atrial appendage and external pulse generator (B). Simultaneous recording of electrocardiogram and intracardiac signal showed sinus rhythm at baseline (C, top) and atrial flutter (cycle length = 240 ms) with variable AV block (C, middle) during stage 1, progressing to 1:1 AV conduction, which coincided with the polymorphic broad complex tachycardia (C, bottom). Typical atrial flutter was inducible at electrophysiological study, and after successful cavotricuspid isthmus ablation, the patient was asymptomatic at follow-up. Atrial flutter with rapid AV conduction may rarely manifest as “polymorphic broad complex tachycardia.”
- Received October 5, 2012.
- Accepted October 9, 2012.
- American College of Cardiology Foundation