New-Onset Device-Detected Atrial Fibrillation in Patients With Atrial Floating Dipole Implantable Cardioverter-Defibrillators: A Propensity Score-Matched Comparison With Conventional Dual-Chamber Systems.

BACKGROUND

Device-detected subclinical atrial fibrillation (DDAF) is a significant risk factor for major cardiovascular events, especially in implantable cardioverter-defibrillator (ICD) recipients. The DX ICD, which utilizes a single ventricular lead with a floating atrial dipole, has demonstrated superior performance in diagnosing DDAF compared to conventional single-lead ICDs. However, comparisons between DX and dual-chamber (DDD) ICDs for atrial monitoring are limited.

OBJECTIVE

To compare the incidence of newly detected DDAF in patients without an indication for atrial pacing who received either a DX or a standard DDD ICD.

METHODS

Remote transmissions from the Italian Home Monitoring Expert Alliance dataset were analyzed. DDAF incidence for different burden cutoffs ( ≥ 15 min, ≥ 6 h, and ≥ 24 h) was compared between groups using propensity score (PS) matching to adjust for baseline characteristics.

RESULTS

In a cohort of 1329 patients (527 with DX ICD and 802 with DDD ICD), 30.7% experienced DDAF lasting ≥ 15 min, 22.3% ≥ 6 h, and 14.0% ≥ 24 h during a median follow-up of 4.5 years. DDAF incidence was lower in the DX ICD group for all burden cutoffs (p < 0.0001). However, after PS matching, DDAF rates were similar between groups, with no significant differences (p ≥ 0.36). Multivariate analysis identified age and 1-month right ventricular pacing percentage as predictors of DDAF across all burden cutoffs, with no effect based on device type or programmed basic rate.

CONCLUSION

In patients without atrial pacing indication or history of clinical atrial fibrillation at implantation, the DX ICD demonstrated DDAF detection capabilities comparable to DDD ICDs in a real-world setting.