Electrocardiographic masking of a myocardial infarction by a fasciculoventricular Mahaim fiber, atrioventricular reentry with anterograde conduction over a fasciculoventricular Mahaim fiber and retrograde conduction over a concealed Kent bundle.
An intracardiac electrophysiologic study was performed in a patient with paroxysmal tachycardia. The patient had two previous episodes of myocardial infarction, but abnormal Q waves were absent in previously obtained electrocardiograms. Electrocardiographic diagnosis of inferior and anterior infarction was made because the electrocardiogram taken on admission temporarily showed abnormal Q waves. Atrioventricular reentry with anterograde conduction over a fasciculoventricular Mahaim fiber and retrograde conduction over a concealed Kent bundle was observed during the tachycardia. It was also demonstrated that electrocardiographic masking of the Q waves was caused by conduction over a fasciculoventricular Mahaim fiber.
D003937:Diagnosis, Differential; D004562:Electrocardiography; D006329:Heart Conduction System / Q000002:abnormalities / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000503:physiopathology; D013617:Tachycardia, Supraventricular / Q000175:diagnosis* / Q000503:physiopathology