Atrial fibrillation is associated with an increased risk of ventricular arrhythmias and sudden death in patients with pacemakers and implantable cardioverter defibrillators (ICDs)
Authors: Fawzy AM , Bisson A , Bodin A , Herbert J , Lip GYH , Fauchier L 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Atrial fibrillation (AF) has been linked to an increase in the risk of ventricular arrhythmias.

Purpose
We aimed to investigate whether AF is associated with an increased risk of ventricular tachycardia (VT), ventricular fibrillation (VF) and sudden death (SD) in patients with cardiac implantable electronic devices (CIEDs).

Methods
All patients hospitalised in France between 2011 and 2020 with a history of pacemakers (PPMs) and implantable cardioverter defibrillator (ICD) were identified from the French National database. Patients with a prior history of VT, VF and SD were excluded.

Results
A total of 701,195 patients were identified. Of these, 581,781 (90.1%) patients had PPMs and 63,726 (9.9%) had ICDs. In the PPM group, 248046 (42.6%) had AF and 333735 (57.4%) had no AF. After multivariable analysis, predictors for VT, VF and SD included sex, diabetes, heart failure, history of pulmonary oedema, valve disease, dilated cardiomyopathy, coronary artery disease (CAD), AF, vascular disease, intracranial bleeding, smoking, dyslipidaemia, alcohol related disorders, lung disease, chronic kidney disease (CKD), thyroid disorders, inflammatory diseases, anaemia, poor nutrition, cognitive impairment, previous cancer and frailty. The incidence of VT, VF and SD was higher in patients with AF (1.47%/year) compared to those without AF (0.94%/year), with the risk significantly elevated in the former group, hazard ratio (HR) 1.554 (confidence interval (CI) 1.508-1.601). After adjustment for confounders (Figure 1), AF was still associated with a significantly increased risk of VT, VF and SD, HR 1.236 (CI 1.198-1.276) in patients with PPMs. This was further demonstrated through a 1:1 propensity score matched (PSM) analysis (n=200977 in each group) where the risk of incident outcomes was significantly higher in PPM patients with AF, HR 1.230 (1.187-1.274), compared to those without AF.
In the ICD group, 20965 (32.9%) had AF and 42761 (67.1%) had no history of AF. Predictors of VT, VF and SD after multivariable analysis included age, sex, diabetes mellitus, heart failure, valve disease, CAD, previous percutaneous coronary intervention, vascular disease, AF, CKD, liver disease and frailty. Incidence of VT, VF and SD was higher in ICD patients with AF (5.30%/ year) compared to those without AF (4.21%/year), with a significantly higher risk, HR 1.261 (CI 1.204-1.320). After adjustment for confounders, this elevated risk was still significant HR 1.167 (1.111-1.226) (Figure 1). 1:1 PSM analysis (n=18349 in each group) demonstrated this further with a significantly elevated risk in ICD patients with AF, compared to ICD patients without AF, HR 1.134 (CI 1.071-1.200).

Conclusion
Our findings suggest that patients with PPM and ICD with concurrent AF are at a higher risk of VT, VF and sudden death compared to patients with PPM and ICD who do not have AF.