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A Rat Model of Ventricular Fibrillation and Resuscitation by Conventional Closed-chest Technique
Published on: April 26, 2015
Morphologic effects of defibrillation: a preliminary report
Insights
Repeated direct current (DC) countershocks can cause significant heart damage, including cell death and hemorrhage. Pathological myocyte contraction, seen in animals after defibrillation, was observed in a human patient, suggesting clinical importance.
Area of Science:
- Cardiovascular pathology
- Electrophysiology
- Medical device research
Background:
- Direct current (DC) countershocks are a critical intervention for cardiac arrhythmias.
- The potential for cumulative cardiac damage from repeated defibrillation is not fully understood.
- Previous studies have documented myocardial injury in experimental animals following defibrillation.
Observation:
- A 72-year-old male patient received over 300 DC countershocks within two weeks.
- Morphological examination revealed subepicardial coagulation necrosis and hemorrhage.
- Pathological contraction of myocytes was observed, a finding previously noted only in animal models.
Findings:
- The patient's heart exhibited significant structural changes post-defibrillation.
- Coagulative necrosis and hemorrhage indicate acute myocardial injury.
- Myocyte contraction, a novel finding in humans, suggests a direct effect of electrical energy on cardiac muscle.
Implications:
- These findings highlight the potential for substantial cardiac morbidity associated with frequent defibrillation.
- The observed myocyte contraction in humans warrants further investigation into its mechanism and clinical significance.
- Clinicians should consider the cumulative effects of DC countershocks when managing patients with refractory arrhythmias.
Abstract:
A 72-yr-old man receiving more than 300 separate DC countershocks in 2 wk exhibited morphologic heart changes, including areas of coagulation necrosis in the subepicardium and areas of frank hemorrhage. In other sites the myocytes were pathologically contracted, a finding previously demonstrated in experimental animals as a result of defibrillation but not seen in man. We suggest that these changes may occur more often than has been previously supposed and thus may be of clinical importance.
