Dr. M. Gabriel Khan is a cardiologist at the Ottawa Hospital and an Associate Professor of Medicine at the University of Ottawa, Canada. He graduated MB, BCh, with First-Class Honors at The Queen's University of Belfast, was appointed Staff Physician in charge of a Clinical Teaching Unit at the Ottawa General Hospital and is a Fellow of the American College of Cardiology, the American College of Physicians, and the Royal College of Physicians of London and Canada. His books include On Call Cardiology, 3^rd edition (2006), Heart Disease Diagnosis and Therapy, 2^nd edition (2006), Rapid ECG Interpretation, 2^nd edition (2003), Cardiac and Pulmonary Management (1993), Medical Diagnosis and Therapy (1994), Heart Attacks, Hypertension and Heart Drugs (1986), and Heart Trouble Encyclopedia (1996). Dr. Khan's books have been translated into numerous languages. He has built a reputation as a clinician-teacher and has become an internationally acclaimed cardiologist through his writings.