Are frequent arrhythmias truly prognostic? The reality of sustained tachycardia in heart failure patients with CIEDs

Introduction

Heart-failure (HF) rehospitalization remains linked to poor prognosis and high resource use. In patients with cardiac implantable electronic devices (CIEDs), continuous monitoring detects arrhythmias with high temporal resolution, enabling personalized risk stratification; however, the specific prognostic value of sustained ventricular tachycardia (SVT), versus non-sustained VT (NSVT), is uncertain. Clarifying this association may guide surveillance and therapy optimization.

Objective

To assess whether CIED-detected SVT and/or NSVT are associated with higher risk of HF rehospitalization.

Methods

Retrospective cohort including 315 HF patients with CIEDs. The primary endpoint was HF rehospitalization (79 events; 25%). Arrhythmias were retrieved from device diagnostics: SVT defined per programmed device criteria (sustained episodes and/or requiring therapy) and NSVT as brief, non-sustained episodes. Multivariable logistic regression (complete-case n=174) adjusted for age, sex, ischemic etiology, left-ventricular ejection fraction (LVEF), SVT, NSVT, and atrial fibrillation. Mean follow-up was 8 years.

Results

A total of 315 patients were included, of whom 79 (25%) experienced HF rehospitalization. Most baseline characteristics were broadly similar between groups, including age, ischemic etiology, LVEF, NYHA class, comorbidities, device type, and HF-directed medical therapies.

In univariate comparisons, female sex was more frequent in the rehospitalization group (p=0.03). TVM also showed a borderline association with the endpoint (p=0.05), whereas TVNM did not differ between groups. No other meaningful univariate differences were observed.

In the multivariable model, SVT emerged as an independent predictor of HF rehospitalizayion (OR 3.15; 95% CI 1.14–8.70; p=0.027). NSVT was not associated with the endpoint (OR 0.9; 95% CI 0.40–2.05; p=0.819). LVEF showed a borderline inverse association (OR 1.04 per 1% decrease; 95% CI 0.999–1.07; p=0.054), while age, sex, ischemic etiology, and atrial fibrillation were not significant independent predictors.

Conclusions

Among patients with HF and CIEDs, SVT—but not NSVT—emerged as an independent predictor of HF rehospitaliza on. Detection of SVT may refine risk stratification and support decisions on follow-up intensity and therapeutic optimization.