Recurrent Ventricular Fibrillation Related to Hypokalemia in Early Repolarization Syndrome

Abstract

We describe a case of early repolarization syndrome in which augmented J waves were documented during an electrical storm associated with hypokalemia. The patient was referred to our hospital for therapy to treat recurrent ventricular fibrillation (VF). The 12-lead electrocardiogram showed giant J waves associated with hypokalemia during multiple episodes of VF. Although antiarrhythmic agents or deep sedation were not effective for the VF, an intravenous supplementation of potassium completely suppressed the VF with a reduction in the J-wave amplitude. Our report discusses the possible relationship between hypokalemia and VF in early repolarization syndrome.

Three cases of corticosteroid therapy triggering ventricular fibrillation in J-wave syndromes

“…In the cases reported here, two of the three patients had hypokalemia, suggesting that hypokalemia, probably induced by corticosteroid therapy, may be closely related to VF episodes, because it is generally accepted that glucocorticoids reduce serum potassium concentration via their mineralocorticoid action. Moreover, in the cases of VF storm we have encountered, in early repolarization syndrome the rapid change in potassium concentration may have been related to the patients’ lethal arrhythmias [8], which would be compatible with the findings of Fujimoto et al [14]. …”

“…Steroids cause hypokalemia via their mineralocorticoid action, so hypokalemia is likely a key trigger of VF in J-wave syndromes, as in the case reported [1, 7, 8]. We have reported a case of early repolarization syndrome related to severe hypokalemia in a 66-year-old man [8]. On the other hand, stress, which may induce the release of intrinsic corticosteroids, is also a likely key triggering factor for VF.…”

“…There has been one case report of VF related to hypokalemia induced by steroid therapy in a patient with Brugada syndrome [7]. Steroids cause hypokalemia via their mineralocorticoid action, so hypokalemia is likely a key trigger of VF in J-wave syndromes, as in the case reported [1, 7, 8]. We have reported a case of early repolarization syndrome related to severe hypokalemia in a 66-year-old man [8].…”

Hypokalemia promotes late phase 3 early afterdepolarization and recurrent ventricular fibrillation during isoproterenol infusion in Langendorff perfused rabbit ventricles

“…Hypokalemia is also associated with ES in structurally normal hearts and correction of hypokalemia can prevent the recurrent ventricular fibrillation (VF). 4, 5 However, because rapid and safe correction of serum potassium is often difficult, additional drug therapy is often necessary to manage the ES. Sympathetic blockade, while not always effective, is commonly used in the management of ES.…”

Comentário a «Padrão de repolarização precoce e risco de morte arrítmica. Meta-análise»

“…Neste âmbito, a identificação de subgrupos de maior risco constitui uma área de intensa investigação, admitindo-se que a elevação do ponto J possa ser um marcador de maior heterogeneidade transmural da repolarização ventricular, capaz de, na presença de fatores pró-arrítmicos ou triggers (alterações do tónus autonómico, hipocaliemia, dispersão da refratariedade ventricular ou potenciais tardios fragmentados) aumentar a vulnerabilidade para FV 14,15 . Apesar de se considerar que a grande maioria dos indivíduos com PRPr terá uma evolução benigna, particularmente se assintomáticos, sem documentação de arritmias ventriculares complexas e sem história familiar de MS 14 , são necessários estudos clínicos e experimentais que permitam contribuir para a compreensão dos mecanismos arritmogénicos relacionados com esta entidade, mantendo uma atitude clínica de precaução por forma a identificar os elementos a ter em conta numa estratégia de estratificação de risco adequada a esta população.…”