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The Innocent Delta Wave in Progressive Cardiomyopathy - Culprit vs Bystander
Ahmad Ghayas Ansari1, Sedhupathi Shanmugam1, Jyothi Vijay1
1Department of Cardiology, Sree Chitra Thirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India.
The American Journal of Cardiology
|July 20, 2026
Summary
This case highlights PRKAG2 mutation-associated glycogen-storage cardiomyopathy, a condition mimicking hypertrophic cardiomyopathy. It features ventricular pre-excitation and progressive conduction disease, underscoring the interplay of structural, electrical, and genetic factors.
Area of Science:
- Cardiology
- Genetics
- Electrophysiology
Background:
- A 34-year-old man presented with recurrent palpitations, dyspnea, and recent ischemic stroke.
- Echocardiography revealed hypertrophic cardiomyopathy (HCM) phenotype with left ventricular (LV) dysfunction.
- Family history positive for HCM and high-grade conduction disease.
Purpose of the Study:
- To present a case of PRKAG2 mutation-associated glycogen-storage cardiomyopathy.
- To illustrate the clinical, electrophysiological, and genetic features of this condition.
- To emphasize the convergence of structural, electrophysiological, and genetic mechanisms.
Main Methods:
- 12-lead electrocardiogram (ECG) and echocardiography.
- Electrophysiological study (EPS) to assess cardiac conduction.
- Cardiac magnetic resonance imaging (CMR) for structural assessment.
- Targeted genetic testing for PRKAG2 variant.
Main Results:
- ECG showed atrial fibrillation (AF) and later a short PR interval with ventricular pre-excitation.
- EPS confirmed a fasciculoventricular pathway with a short, fixed HV interval.
- CMR revealed asymmetric septal hypertrophy with late gadolinium enhancement.
- Genetic testing identified a pathogenic PRKAG2 variant (c.905G>A, p.Arg302Gln).
Conclusions:
- PRKAG2 mutation-associated glycogen-storage cardiomyopathy is a phenocopy of HCM.
- The condition is characterized by ventricular pre-excitation and progressive conduction disease.
- Management involves heart failure, anticoagulation, AF rhythm control, and family screening.
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