Clinical characteristics, management, and outcomes of patients with electrical storm: single centre experience
Authors: Di Fusco S.A , Pignalberi C , Spinelli A , Baca M , Cappuccio C , Russo M , Pandozi C , Colivicchi F 
Published: October 2021

Abstract

Background
Electrical storm (ES) is a life-threatening condition caused by recurrent malignant ventricular arrhythmia (≥3 episodes of ventricular tachycardia (VT) or ventricular fibrillation within 24 hours). ES patient management is challenging and can involve antiarrhythmic medication, sedation, and invasive procedures such as catheter ablation.

Purpose
The aim of this study is to report the clinical profile and management of ES patients who attended an arrhythmia reference centre.

Methods
Patients who presented with ES at our centre over a five-year period were consecutively enrolled. Patient data were retrospectively collected from hospital records. Patients with in-hospital death were excluded form data analysis.

Results
Seventy-six patients were included (84% male, mean age 73±10 years). 55% of patients had ischemic heart disease. The mean left ventricle ejection fraction (LVEF) was 33±4%, with 22% of patients having a severe reduction in systolic ventricular function (EF &lt;35%). Baseline characteristics are reported in Table 1. During hospitalisation, 30% of patients underwent coronary angiography and 30% of these had percutaneous coronary revascularization. Patients were managed with pharmacological treatment, including continuous infusion of antiarrhythmic drugs (45% of patients received at least one antiarrhythmic), sedation (12%), and electrolytic solutions (38%). More details on ES management are reported in Table 2. All patients were evaluated for transcatheter ablation. After a mean of 6 days, 25% underwent transcatheter VT ablation during hospitalisation. In 7 patients (9%), catheter ablation was planned and performed during a subsequent hospitalisation.
At discharge, 93% of patients received beta blockers and 68% received amiodarone. Overall, 65% were discharged with at least two antiarrhythmic drugs. The mean length of hospitalisation was 10±9 days, with 6±4 days spent in the intensive care unit. Eighteen patients (23%) had at least one subsequent hospitalisation for ES. After a mean follow-up of 20 months, the cumulative mortality rate was 27%, without a significant difference in mortality rates between ablated and non-ablated patients (27% and 28%, respectively). Baseline mean creatinine levels were higher (1.73±1.1 vs. 1.27±0.1 mg/dl, p&lt;0.05), and LVEF was lower (27±3% vs. 35±17%, p&lt;0.05) in patients who died during follow-up as compared to survivors. A trend toward a longer QTc interval duration (482±47 vs. 467±28 ms) and longer QRS duration (139±36 vs. 131±7 ms) was also found among patients who died during follow-up.

Conclusion
In our centre, ischemic heart disease was the most common heart disease in patients presenting with ES. In more than one third of patients, VT transcatheter ablation was performed as a therapeutic strategy in addition to drug therapy. Among patients who died during the follow-up, baseline creatinine levels were higher and LVEF was lower compared with survivors.

Funding Acknowledgement
Type of funding sources: None. Table 1Table 2