Coexistence of atrioventricular accessory pathways and drug-induced type 1 Brugada pattern

Pacing Clin Electrophysiol. 2018 Sep;41(9):1078-1092. doi: 10.1111/pace.13414. Epub 2018 Jul 16.

Abstract

Background: Atrial arrhythmias, particularly atrioventricular nodal reentrant tachycardia, can coexist with drug-induced type 1 Brugada electrocardiogram (ECG) pattern (DI-Type1-BrP). The present study was designed to determine the prevalence of DI-Type1-BrP in patients with atrioventricular accessory pathways (AV-APs) and to investigate the clinical, electrocardiographic, electrophysiologic, and genetic characteristics of these patients.

Methods: One-hundred twenty-four consecutive cases of AV-APs and 84 controls underwent an ajmaline challenge test to unmask DI-Type1-BrP. Genetic screening and analysis was performed in 55 of the cases (19 with and 36 without DI-Type1-BrP).

Results: Patients with AV-APs were significantly more likely than controls to have a Type1-BrP unmasked (16.1 vs 4.8%, P = 0.012). At baseline, patients with DI-Type1-BrP had higher prevalence of chest pain, QR/rSr' pattern in V1 and QRS notching/slurring in V2 and aVL during preexcitation, rSr' pattern in V1 -V2 , and QRS notching/slurring in aVL during orthodromic atrioventricular reentrant tachycardia (AVRT) compared to patients without DI-Type1-BrP. Abnormal QRS configuration (QRS notching/slurring and/or fragmentation) in V2 during preexcitation was present in all patients with DI-Type1 BrP. The prevalence of spontaneous preexcited atrial fibrillation (AF) and history of AF were similar (15% vs 18.3%, P = 0.726) in patients with and without DI-Type1-BrP, respectively. The prevalence of mutations in Brugada-susceptibility genes was higher (36.8% vs 8.3%, P = 0.02) in patients with DI-Type1-BrP compared to patients without DI-Type1-BrP.

Conclusions: DI-Type1-BrP is relatively common in patients with AV-APs. We identify 12-lead ECG characteristics during preexcitation and orthodromic AVRT that point to an underlying type1-BrP, portending an increased probability for development of malignant arrhythmias.

Keywords: Brugada syndrome; Wolff-Parkinson-White syndrome; atrioventricular reentrant tachycardia; genetics; preexcitation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Accessory Atrioventricular Bundle / complications*
  • Accessory Atrioventricular Bundle / physiopathology*
  • Adolescent
  • Adult
  • Aged
  • Ajmaline
  • Brugada Syndrome / chemically induced*
  • Brugada Syndrome / complications*
  • Brugada Syndrome / physiopathology*
  • Case-Control Studies
  • Echocardiography
  • Electrocardiography
  • Electrophysiologic Techniques, Cardiac
  • Female
  • Humans
  • Male
  • Middle Aged
  • Phenotype
  • Pre-Excitation Syndromes / complications*
  • Pre-Excitation Syndromes / physiopathology*
  • Radiofrequency Ablation
  • Tachycardia, Atrioventricular Nodal Reentry / complications*
  • Tachycardia, Atrioventricular Nodal Reentry / physiopathology*

Substances

  • Ajmaline