The tracing shown was observed at EP study in a young man without evidence of heart disease. What is the likely mechanism of tachycardia for both the narrow and wide QRS complex arrhythmias? Source: Wide QRS Complex Tachycardia, Clinical Electrophysiology Review, 2e Citation: Klein GJ, Prystowsky EN. Clinical Electrophysiology Review, 2e; 2016 Available at: http://accesscardiology.mhmedical.com/DownloadImage.aspx?image=/data/Books/1787/kleincer_ch5_f0019A.png&sec=120739309&BookID=1787&ChapterSecID=120739209&imagename= Accessed: October 09, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved