Sections View Full Chapter Figures Tables Videos Full Chapter Figures Tables Videos Supplementary Content ++ ECG Findings ++ Wide-complex irregular, extreme tachycardia QRS complexes with changing morphology ++ Pearls ++ Polymorphic ventricular tachycardia (PVT) may occur in association with a normal QT interval or a prolonged QT interval. When associated with a prolonged QT interval, torsades de pointes is diagnosed. Normal-QT PVT is typically associated with cardiac ischemia. Immediate treatment consists of cardioversion; ventricular antiarrhythmics such as amiodarone, procainamide, or lidocaine may be used followed by assessment for and treatment of ischemia. Torsades de pointes (literally translated “twisting of the points” in French) has a characteristic “twisting” appears of the QRS complexes around the ECG baseline, as shown in Figs. 23.24A-B. Immediate treatment for torsades de pointes consists of cardioversion; if cardioversion is unsuccessful, a bolus of intravenous magnesium should be given. If the arrhythmia persists, overdrive electrical pacing or overdrive chemical pacing (with isoproterenol) will help shorten the relative QT and convert the patient back to sinus rhythm. Following conversion, a magnesium infusion should be initiated, and the cause of the prolonged QT should be aggressively sought out and treated. ++ FIGURE 23.35A Torsades de Pointes. (ECG contributor: James V. Ritchie, MD.) Graphic Jump LocationView Full Size|Favorite Figure|Download Slide (.ppt) ++ FIGURE 23.35B Very rapid wide-complex tachycardia with sine wave appearance and fluctuations in the amplitude of the QRS complexes consistent with torsades de pointes. Graphic Jump LocationView Full Size|Favorite Figure|Download Slide (.ppt) GET ACCESS TO THIS RESOURCE Sign In Username Error: Please enter User Name Password Error: Please enter Password Forgot Username? Forgot Password? Sign in via OpenAthens Sign in via Shibboleth Get Free Access Through Your Institution Contact your institution's library to ask if they subscribe to McGraw-Hill Medical Products. Access My Subscription GET ACCESS TO THIS RESOURCE Subscription Options Pay Per View Timed Access to all of AccessEmergency Medicine 24 Hour $34.95 (USD) Buy Now 48 Hour $54.95 (USD) Buy Now Best Value AccessEmergency Medicine Full Site: One-Year Individual Subscription $595 USD Buy Now View All Subscription Options