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Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Effect of cardiac resynchronization therapy on the incidence of electrical storm
Peter Nordbeck1, Bernhard Seidl, Beatrix Fey
1Department of Internal Medicine I, University Hospital Würzburg, Germany.
Insights
Cardiac resynchronization therapy (CRT-D) significantly reduces electrical storm incidence in heart failure patients compared to implantable cardioverter-defibrillators (ICD). This therapy may also lower arrhythmia burden, improving outcomes for heart failure patients.
Area of Science:
- Cardiology
- Electrophysiology
- Heart Failure Management
Background:
- Biventricular pacing's hemodynamic benefits are known, but its electrophysiologic effects require systematic study.
- Electrical storm (ES) is a critical event in heart failure patients with implantable devices.
- Investigating ES incidence and risk factors in CRT-D versus ICD patients is crucial.
Purpose of the Study:
- To compare the incidence of electrical storm (ES) in heart failure patients receiving cardiac resynchronization therapy with a defibrillator (CRT-D) versus standard implantable cardioverter-defibrillators (ICD).
- To identify risk factors associated with electrical storm in this patient population.
Main Methods:
- Retrospective analysis of 729 heart failure patients (168 CRT-D, 561 ICD).
- Electrical storm defined as ≥3 episodes of ventricular tachycardia/fibrillation within 24 hours.
- Mean follow-up duration of 41 months.
Main Results:
- Electrical storm occurred in only 0.6% of CRT-D patients versus 7% of ICD patients (p<0.01).
- Patients experiencing electrical storm had a significantly increased one-year mortality risk (33%).
- Secondary prevention indication and left ventricular ejection fraction <30% were significant predictors of electrical storm.
Conclusions:
- Cardiac resynchronization therapy (CRT-D) is associated with a substantially lower incidence of electrical storm compared to ICDs in heart failure patients.
- Electrical storm presence significantly increases mortality risk, underscoring the need for effective preventive strategies.
- CRT may offer additional benefits beyond hemodynamic improvement by reducing arrhythmia burden in heart failure.
Background:
Hemodynamic improvement from biventricular pacing is well documented; however, its electrophysiologic effects have not been systematically studied. In this study, incidence and risk factors for electrical storm (ES) were investigated in 729 ICD and biventricular defibrillator (CRT-D) heart failure patients.
Methods:
168 consecutive CRT-D and 561 ICD patients were retrospectively analyzed for the occurrence of VT/VF and predisposing factors. Electrical storm was defined as ventricular tachycardia or fibrillation ≥3 times during 24 h. Mean follow-up was 41 months.
Results:
In 168 CRT-D patients only one patient experienced electrical storm compared to 39 patients out of 561 ICD patients (0.6% vs. 7%, p<0.01). 33% of the patients with electrical storm died within one year. In the CRT-D group 81 patients (48%) developed VT or VF and received at least one appropriate therapy, compared to 281 patients (50%) in the ICD group. Mean ejection fraction was 21.7% in the CRT-D group and 34.7% (p<0.01) in the ICD group. Stratifying the patients according to primary or secondary prevention and ejection fraction demonstrated that VT/VF clusters were significantly associated with ICD indication for secondary prevention, previous myocardial infarction and LVEF<30%.
Conclusion:
The development of electrical storm is accompanied with a highly increased mortality risk even if an ICD/CRT-D is implanted. In CRT-D patients electrical storm is much less common than in ICD patients. Secondary prevention and ejection fraction<30% are predictors of electrical storm. Beside hemodynamic improvements cardiac resynchronization therapy may reduce the arrhythmia burden in heart failure patients.
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