Masahito Satoh

Electrophysiologic Evaluation of Asymptomatic Patients with the Wolff-Parkinson-White Pattern

In the past 4 years, 34 asymptomatic patients with the Wolff‐Parkinson‐White (WPW) pattern underwent electrophysiologic study. The effective refractory period (ERP) of antegrade conduction over the accessory pathway was 288 ± 29 msec. In three asymptomatic patients (9%), the antegrade ERP of the accessory pathway was shorter than 250 msec. The antegrade ERP of the accessory pathway became shorter than 250 msec in an additional 12 of 22 (55%) patients after isoproterenol administration. Nineteen (56%) of the asymptomatic patients showed the absence of retrograde conduction over the accessory pathway even after isoproterenol administration. The rate of induction of orthodromic reciprocating tachycardia in the asymptomatic WPW patients was 15% (5/34), which was significantly lower than that in the symptomatic patients. These data suggest that in the asymptomatic patients, the absence of retrograde conduction over the accessory pathway is the reason they remained asymptomatic, free of reciprocating tachycardia. However, even in the asymptomatic patients, some had the accessory pathway in which antegrade ERP was shorter than 250 msec. They may result in rapid ventricular conduction over the accessory pathway when atrial fibrillation develops.

Dynamicity of J waves during coronary intervention and angiography in a patient with non-Q inferior myocardial infarction

Slurs or notches at the terminal portion of the QRS complexes are called J waves, which may be associated with myocardial ischemia. We describe our experience with a case of a patient with acute inferior myocardial infarction in whom J waves were observed in the inferior leads with ST‐segment elevation. The coronary artery was completely occluded, and during percutaneous intervention, ST‐segment elevation was normalized first, followed by the disappearance of the J waves after full revascularization. On follow‐up coronary angiography (CAG), the J waves in the inferior leads reappeared during the right CAG. The J waves were associated with an alteration of the electrical axis. J waves developing in association with myocardial ischemia seemed to be more sensitive to ischemia and might represent a depolarization abnormality.