McGill Case 357

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. Previous Case: McGill Case 356 | Next Case: McGill Case 358

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.