THE ROLE OF DIFFERENT TYPES OF ATRIAL FIBRILLATION ON APPROPRIATE AND INAPPROPRIATE DEVICE THERAPY AND SURVIVAL IN IMPLANTABLE CARDIOVERTER DEFIBRILLATOR PATIENTS

Abstract

Background: The prevalence of atrial fibrillation (AF) has taken epidemic proportions in the population with cardiovascular disease. However, the prognostic importance of different types of AF in implantable cardioverter defibrillator (ICD) patients remains unclear. The current study assessed the prevalence of different types of atrial fibrillation and their prognostic importance in ICD recipients. Methods: Data on 913 (79% men, mean age 62 ± 13 years) consecutive patients receiving an ICD at the Leiden University Medical Center were prospectively collected. Among other characteristics, the existence and type of AF (paroxysmal, persistent or permanent) was assessed at implantation. During follow-up, the occurrence of appropriate or inappropriate device therapy, as well as mortality was noted. Results: At implantation, 73% of patients had no history of AF, 9% had a history of paroxysmal AF, 7% had a history of persistent AF and 11% had permanent AF. During 833 ± 394 days follow-up, 117 patients (13%) died, 228 patients (25%) experienced appropriate device discharge and 139 patients (15%) received inappropriate shocks. Patients with permanent AF exhibited approximately twice the risk for mortality (HR 1.7, 95% CI 1.02.7, p=0.033), ventricular arrhythmias triggering device discharge (HR 2.2, 95% CI 1.6-3.2, p<0.001), and inappropriate device therapy (HR 2.7, 95% CI 1.7-4.4, p<0.001). In contrary, patients with paroxysmal or persistent AF did not show a significant increased risk for mortality or appropriate device therapy but demonstrated almost three times risk for inappropriate device therapy (HR 2.9, 95% CI 1.7-4.8, p<0.001). Conclusions: In the population currently receiving ICD treatment outside the setting of clinical trials a large portion has either a history of AF or permanent AF. Both types of AF have prognostic implications for mortality and appropriate, as well as inappropriate device discharge.