A Case Report of Short-Coupled Ventricular Fibrillation Unmasked During Post-Infarction Inflammatory Remodeling

Area of Science:

• Cardiology
• Electrophysiology
• Internal Medicine

Background:

• Short-coupled ventricular fibrillation (SC-VF) is typically idiopathic, occurring in hearts without structural abnormalities.
• Acute myocardial infarction (AMI) triggers cardiac remodeling, potentially unmasking latent electrophysiological vulnerabilities.
• The subacute phase post-AMI presents a unique window for SC-VF emergence.

Purpose of the Study:

• To illustrate the rare occurrence of SC-VF during the subacute remodeling phase after AMI.
• To highlight the clinical significance of ultra-short-coupled premature ventricular contractions (PVCs) as a trigger for SC-VF.
• To demonstrate an alternative therapeutic approach for refractory SC-VF post-AMI.

Main Methods:

• Case report of a 49-year-old male following anterior ST-segment elevation myocardial infarction (STEMI).
• Analysis of triggered arrhythmias by ultra-short-coupled PVCs (coupling interval = 240ms).
• Evaluation of therapeutic response to lidocaine and subsequent verapamil administration.

Main Results:

• The patient experienced an electrical storm of polymorphic ventricular tachycardia and VF refractory to lidocaine.
• Prompt identification of the SC-VF phenotype enabled verapamil administration, suppressing the arrhythmia despite a mildly reduced LVEF (43%).
• An implantable cardioverter-defibrillator (ICD) was implanted for secondary prevention.

Conclusions:

• Post-AMI inflammatory remodeling can unmask latent electrophysiological issues leading to SC-VF.
• An ultra-short coupling interval (<300ms) is a critical marker for guiding therapy towards calcium channel antagonism.
• This case expands the understanding of SC-VF etiology and management in the context of ischemic heart disease.