Sections View Full Chapter Figures Tables Videos Full Chapter Figures Tables Videos Supplementary Content ++ ECG Findings ++ QRS amplitude of ≤ 5 mm in all limb leads or QRS amplitude ≤ 10 mm in all precordial leads ++ Pearls ++ Differential diagnosis includes normal variant, low standardization of the ECG machine, pericardial or pleural effusion, obesity, anasarca, COPD/emphysema, cardiac infiltrate (tumor, amyloid), MI, myocarditis, cardiomyopathy, adrenal insufficiency, or hypothyroidism. Always check the calibration markings on the ECG to check for low standardization of the ECG machine as an etiology for the observed tracing. ++ FIGURE 23.55A Low-Voltage ECG with Underlying Atrial Flutter. (ECG contributors: Clifford L. Freeman, MD, and Nicole S. McCoin, MD.) Graphic Jump LocationView Full Size|Favorite Figure|Download Slide (.ppt) ++ FIGURE 23.55B QRS height is less than 5 mm in the precordial leads in this normally calibrated tracing. 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