The World Trade Center attack: increased frequency of defibrillator shocks for ventricular arrhythmias in patients living remotely from New York City.

OBJECTIVES: The goal of this study was to determine whether the World Trade Center (WTC) attack on September 11, 2001, had an effect on the occurrence of ventricular arrhythmias among patients with implantable cardioverter-defibrillators (ICDs) living in Florida.
BACKGROUND: Increased frequencies of ICD therapies for ventricular arrhythmias were reported among patients in New York City after the attack on the WTC. Whether this effect also occurred in patients living geographically distant from New York is unknown.
METHODS: This was an observational study consisting of 132 ICD patients who presented to the University of Florida and the Veterans Affairs Medical Center in Gainesville, Florida, for routine ICD follow-up around the time of the WTC attack. The occurrence of ventricular tachyarrhythmias triggering ICD therapy in the 30 days before and after September 11 constituted the primary end point.
RESULTS: In the 30 days following the WTC attack, a total of 14 patients (11%) had ventricular tachyarrhythmias, compared with 5 (3.8%) in the preceding 30 days (p = 0.0389, 95% confidence interval [CI] 0.4 to 13.3). This represents a 2.8-fold risk increase. Patients with ventricular arrhythmias both before and after September 11 demonstrated a rate increase of 2.38 events per patient (p = 0.0231, 95% CI 1.03 to 13.97).
CONCLUSIONS: The frequency of ventricular arrhythmias requiring ICD treatment increased by 68% among patients in Florida around the WTC attack. These findings suggest that stress-related arrhythmogenesis due to the WTC tragedy was not restricted to the geographic location of the attack. A major national tragedy may cause widespread increased risk of potentially life-threatening ventricular arrhythmias.