title: Wolff-Parkinson-White syndrome type B and left bundle-branch block: electrophysiologic and radionuclide study.
abstract: Coinciding left bundle-branch block and Wolff-Parkinson-White syndrome type B, a very rare electrocardiographic occurrence, was found in a patient with dilated cardiomyopathy. Electrophysiologic study revealed eccentric retrograde atrial activation during ventricular pacing, suggesting right-sided accessory pathway. At programmed atrial pacing, effective refractory period of the accessory pathway was 310 ms; at shorter pacing coupling intervals, normal atrioventricular conduction with left bundle-branch block was seen. Left bundle-branch block was seen also with His bundle pacing. Radionuclide phase imaging demonstrated right ventricular phase advance and left ventricular phase delay; both right and left ventricular phase images revealed broad phase distribution histograms. Combined electrophysiologic and radionuclide investigations are useful to disclose complex conduction abnormalities and their mechanical correlates.
mesh_terms: D000368:Aged; D002037:Bundle-Branch Block / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology; D004562:Electrocardiography; D004594:Electrophysiology; D005260:Female; D006801:Humans; D011877:Radionuclide Imaging; D013667:Technetium; D014927:Wolff-Parkinson-White Syndrome / Q000145:classification / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology
chemical_list: D013667:Technetium