This case report is kindly provided by Michael Rosengarten from McGill and is part of the McGill Cases. These cases come from the McGill EKG World Encyclopedia.
This is a regular rhythm with a ventricular rate of 70/min. The QRS has a left axis deviation and a dominant R wave in V1. The PR interval is 260 ms. This tracing suggests a first degree heart block with a left anterior hemi block and RBBB. This has been called Trifasicular block.
