At least a half-dozen times per year, an acute care physician sends me an ECG demonstrating a regular monomorphic wide complex tachycardia (WCT), asking me for my thoughts about the diagnosis. The backstory is almost always the same: The physician assumed that the WCT was a supraventricular tachycardia with aberrant conduction (SVT-AC) and treated it as such. The patient had a poor outcome because the diagnosis should have been ventricular tachycardia (VT). Consequently, the physician is criticized for poor decision-making and then sends me the case, hoping I will support their decision-making.
Figure. Courtesy of Amal Mattu, MD
The Figure demonstrates an example. This is the ECG of a 45-year-old man who presented to an emergency department in a country in which the specialty of emergency medicine was still developing. The patient was hemodynamically stable and had no history of coronary disease. The ECG was read as SVT with right bundle branch block. When two doses of IV adenosine failed to convert the patient's rhythm, two doses of IV metoprolol were administered. After the second dose, the patient suddenly became hypotensive (blood pressure 60/35 mm Hg). The physician attempted cardioversion, which led to ventricular fibrillationThe physician then defibrillated the patient, which resulted in return of spontaneous circulation. This near-death experience significantly compromised the level of respect for the emergency physician group within the hospital. The electrophysiology lab later confirmed VT.
