Early relevant alerts from remote monitoring in heart failure patients with a cardiac implanted electronic device: what implications for long term outcome?

Abstract

Abstract Background Alarms generated by remote monitoring (RM) of cardiac implantable electronic devices (CIEDs) have been associated with worse clinical outcomes in patients with heart failure (HF). However, whether the timing of RM alerts impact on the clinical trajectories of HF patients is still debated. Purpose To examine the impact of alerts occurring in the first 180 days after CIED implant on clinical outcomes, as well as potential predictors. Methods we retrospectively enrolled all patients with a history of HF implanted with a CRT-D or an ICD at our tertiary. We collected data regarding ATP, shock and HF score above threshold (defined as multiparametric scores provided and validated by all CIED manufacturers). We defined early relevant alerts (Early-RA) as alarms received during the first 180 days after implant. The primary clinical outcome of the study was a composite of death or HF hospitalization. Logistic and Cox regression analyses were used to determine associations. The occurrence of early-RA was used as a time dependent covariate. Results A total of 272 patients were included in the analysis (median age 67.4 years, IQR 58.6-74.6, 19.9% female). Twenty patients had an early-RA (7.3% of the overall study population) and were found to be older, more severely symptomatic for HF, with a higher prevalence of atrial fibrillation (AF) and chronic kidney disease (CKD) (all p values<0.05). On the other hand, HF etiology and prevalence of CRT-D did not differ between the two groups. At univariate logistic regression analysis, we found the following factors as significantly associated with early-RA: age (odds ratio [OR] 1.04, 95% confidence interval [CI] 1.00-1.10), NYHA class (OR 2.44, 95% CI 1.01-5.82) and CKD (OR 3.41, 95% CI 1.21-8.98), but these results were not confirmed at the multivariable logistic regression. After a median follow-up of 959 days (IQR 432-1484), patients reporting an early-RA had more primary outcome events (45.0% vs 12.3% p<0.001). At time-dependent multivariable Cox regression analysis adjusted for age, sex, left ventricular ejection fraction and type of CIED, we found that early-RA were independently associated with a higher risk of the primary outcome (hazard ratio [HR] 3.61, 95%CI 1.42-9.18) (Figure). Early-RA were also associated with a higher risk of death (HR 5.58, 95% CI 1.68-18.50) while no significant association was found for HF hospitalization (HR 2.46, 95% CI 0.80-7.57, p=0.116). Conclusions The occurrence of alerts detected by RM of CIEDs in a relatively early phase (within 180 days from implant), is associated with a higher risk of a composite of death and HF hospitalization in HF patients.Study Outcome according to Early RATime dependent Cox regression