From a wide to a narrow QRS tachycardia and back. What is the mechanism?
A 40-year-old man developed a near syncope during exercise due to a wide complex tachycardia with periods of changing RR intervals accompanied by changes in QRS morphology. The differential diagnosis of this electrocardiographic pattern is discussed.
Department of Cardiology, University Hospital Ghent, Ghent, Belgium. vfirsovaite@hotmail.com
Vida
V
Firsovaite
Mattias
M
Duytschaever
Rene
R
Tavernier
D000328:Adult; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000503:physiopathology*; D003937:Diagnosis, Differential; D004562:Electrocardiography; D004630:Emergencies; D015444:Exercise; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D013575:Syncope / Q000209:etiology; D017180:Tachycardia, Ventricular / Q000175:diagnosis* / Q000503:physiopathology*