RESUMO
Supernormal conduction is defined as better-than-expected conduction in patients with depressed conduction during a short interval in the ventricular cycle. It is mainly observed in long-duration electrocardiogram (ECG) assessments. Its occurrence during 12-lead ECG is uncommon and its interpretation demands knowledge on electrophysiological alterations that are hard to understand. By reporting this case we aim to propose a rationale sequence that should be considered when facing an ECG with these same features, which would enable a greater accuracy to make a definitive diagnosis.
Assuntos
Arritmias Cardíacas/classificação , Arritmias Cardíacas/diagnóstico , Eletrocardiografia/métodos , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
P-wave dispersion (PWD, Pd or Pdis) is a noninvasive electrocardiographic (ECG) marker for atrial remodeling and predictor for atrial fibrillation (AF). PWD is defined as the difference between the widest and the narrowest P-wave duration recorded from the 12 ECG leads. Increased P-wave duration and PWD reflect prolongation of intraatrial and interatrial conduction time with lack of a well-coordinated conduction system within the atrial muscles, with inhomogeneous, asynchronic, pro-inflammatory and anti-inflammatory effect mediated by interleukin-6 (IL-6) in patients with the CG + GG genotype IL-6 -634C/G polymorphism [1] and discontinuous propagation of sinus impulses mainly between the left and right atria, interstitial/extracellular fibroblast activation and collagen deposition with fibrosis (via TGF-ß) in atrial tissue, insufficient blood supply, significant not isotropic myoelectric activity, and thin wall thickness and consequent expansion tendency all well-known electrophysiological characteristics in patients with atrial arrhythmias and especially paroxysmal atrial fibrillation (PAF) [2].