Key result
His bundle recordings suggest bidirectional tachycardia stems from macroreentry involving the left branch fascicles.
Why the study?
The mechanism underlying bidirectional tachycardia remains unclear and requires elucidation through intracardiac recordings and programmed electrical stimulation.
What is the mechanism of bidirectional tachycardia based on intracardiac recordings and programmed electrical stimulation?
Case Report (n=1)
What is the mechanism of bidirectional tachycardia based on intracardiac recordings and programmed electrical stimulation?
This case report provides electrophysiological evidence that macroreentry involving the two fascicles of the left bundle branch may be a mechanism for bidirectional tachycardia.
Supports left fascicular macroreentry as possible mechanism in bidirectional tachycardia; leaves open generalizability beyond this case.
His bundle recordings and programmed electrical stimulation were performed in a 70-year-old woman with bidirectional tachycardia; the recordings demonstrated the infra-Hissian origin of the tachycardia. Occurrence of the His deflection slightly after the onset of ventricular depOlarization suggested that the origin of the tachycardia was located near the His bundle bifurcation. Recording of three atrial sites during tachycardia allowed the study of retrograde atrial activation. Two sets of fairly constant and alternating VA intervals were recorded. This fact is consistent with two ventricular circuits used alternatively. The tachycardia could also be interrupted with a single atrial or ventricular premature beat. It is postulated that the tachycardia is due to macroreentry involving the two fascicles of the left branch. This study suggests that reentry may be a possible mechanism in some cases of bidirectional tachycardia.
No takes yet. Share an insight, caveat, or question.
Lévy et al. (1982) conducted a case report in Bidirectional tachycardia (n=1). His bundle recordings and programmed electrical stimulation was evaluated on Mechanism of bidirectional tachycardia. His bundle recordings and programmed electrical stimulation suggested that bidirectional tachycardia may be due to macroreentry involving the two fascicles of the left branch.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: