De novo clinical AF post-ICD was linked to a 2.41-fold higher risk of mortality/heart transplant/VAD, unlike subclinical AF, over a median 6.2-year follow-up.
Does the development of de novo clinical or subclinical atrial fibrillation increase the risk of mortality, heart transplantation, or ventricular assist device implantation in ICD recipients with cardiomyopathy?
In ICD recipients with cardiomyopathy, the development of de novo clinical atrial fibrillation, but not subclinical atrial fibrillation, is independently associated with an increased risk of mortality, heart transplantation, or VAD implantation.
Absolute Event Rate: 0% vs 0%
Abstract Background The reported incidence of de novo subclinical (SCAF) and clinical atrial fibrillation (AF) in patients who received an Implantable Cardioverter-Defibrillator (ICD) varies across studies. The clinical impact of de novo SCAF in ICD patients, and how it compares to de novo clinical AF, remains a matter of debate. Purpose To perform a comparative analysis of the incidence of de novo SCAF and clinical AF in patients with an ICD and their association with adverse outcomes. Methods De novo diagnosis of SCAF or clinical AF following ICD implantation was retrospectively assessed in a single center retrospective registry of ICD patients with ischemic or non-ischemic cardiomyopathy. Patients with a prior diagnosis of AF before ICD implantation were excluded. De novo AF was assessed calculating incidence, construction of cumulative incidence functions, and a forward stepwise Cox proportional hazards model. Further, a Cox proportional hazards model for the composite outcome of mortality, heart transplantation, or the implantation of a ventricular assist device (Mort/HTx/VAD) was performed with de novo AF as time-varying covariate. Model performance, after the inclusion of de novo AF on top of a multivariate baseline model with known risk factors (Table 1), was assessed by analyzing the difference in log-likelihood ratio (Δ−2 LLR) using chi-squared analysis. Results After exclusion of patients with prior diagnosis of AF 1014 out of 1615 patients (62.8%) were included in the analysis. The incidence of de novo AF (Figure 1) was 4.1% (95%CI 3.6 – 4.7) for SCAF and 3.0% (95%CI 2.6 – 3.5) for clinical AF during a median follow-up of 6.2 years (IQR 3.2 – 10.3). A higher age at implantation (HR 1.02, 95% CI 1.01–1.03, p 0.001) and use of loop diuretics (HR 1.79, 95% CI: 1.38–2.33, p 0.001) were associated with a higher incidence of SCAF, while the use of Class III anti-arrhythmic drugs was independently associated with a lower incidence of SCAF (HR 0.55, 95% CI: 0.39–0.76, p 0.001). A higher age at implantation (HR 1.04, 95% CI: 1.02–1.05, p 0.001) was the only association with clinical AF in a multivariate model. The results of the Cox proportional hazards model are shown in Table 1. Both diagnosis of SCAF (HR 1.41, 95%CI 1.11 – 1.78, p=0.004) and clinical AF (HR 2.65, 95%CI 2.11 – 3.33, p 0.001) were univariately associated with a higher incidence of Mort/HTx/VAD. In multivariate analysis, only de novo clinical AF was significantly associated with Mort/HTx/VAD (HR 2.41, 95%CI 1.91 – 3.03, p 0.001) and resulted in a significant increase in predictive performance when compared to the baseline model (Δ−2 LLR 48.81, p 0.001). Conclusion De novo AF, both subclinical and clinical, is common in patients who have received an ICD, yet prediction of de novo AF is challenging in this population. The onset of de novo clinical AF during follow-up was independently associated with a higher incidence of Mort/HTx/VAD, whereas SCAF was not.Figure 1 Table 1
Blondeel et al. (Sat,) reported a other. De novo clinical AF post-ICD was linked to a 2.41-fold higher risk of mortality/heart transplant/VAD, unlike subclinical AF, over a median 6.2-year follow-up.