title: Malignant arrhythmia in apical ballooning syndrome: risk factors and outcomes.
abstract: OBJECTIVE
  We sought to determine the frequency and outcomes with symptomatic arrhythmia in patients with apical ballooning syndrome (ABS).
  
  
  METHODS
  A retrospective review of the Mayo Clinic Angiography database was conducted to identify patients who met the Mayo criteria for ABS. Patients with documented arrhythmias formed the study group, and 31 randomly selected patients with ABS but without arrhythmia formed the control group.
  
  
  RESULTS
  Out of 105 patients identified with ABS, 6 (5.7%) women aged 69 +/- 9 years experienced significant arrhythmia (ventricular fibrillation, asystole), 2 patients died, and 1 required permanent pacemaker implantation. When compared with controls, the study group showed no significant difference with respect to ECG characteristics (QT, QRS duration or axis) except for R-R interval variability (see comments below) (30.6+/-6 vs 14.5+/-17 p = 0.0004), QTc, and P-R interval. Patients without arrhythmia were more likely to be on beta-blocker therapy than the study population (33% vs 80.6% p = 0.02).
  
  
  CONCLUSIONS
  Life-threatening arrhythmia is uncommon (5.7%) with ABS despite marked, structural abnormalities. When arrhythmias do occur, the outcome is poor. Prominent variability in R-R intervals appears to be predictive of significant arrhythmias in ABS. The role of beta-blocker therapy in preventing arrhythmia with ABS requires further investigation.
authors.affiliation: Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic,Rochester, Minnesota, USA.
authors.forename: Chadi
authors.initials: C
authors.lastname: Dib
authors.forename: Abhiram
authors.initials: A
authors.lastname: Prasad
authors.forename: Paul A
authors.initials: PA
authors.lastname: Friedman
authors.forename: Elesber
authors.initials: E
authors.lastname: Ahmad
authors.forename: Charanjit S
authors.initials: CS
authors.lastname: Rihal
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Hammill
authors.forename: Samuel J
authors.initials: SJ
authors.lastname: Asirvatham