The patient is a 46-year-old male with a history of hypertension and congestive heart failure who presents complaining of his defibrillator firing—twice yesterday and once today. He denies chest pain, shortness of breath, fever, nausea or vomiting. He ran out of his carvedilol about 1 month ago.

 View the initial ECG and consider what your diagnosis and next steps would be.

46-year-old's defibrillator firing
Figure 1. Initial ECG (Case presented by Catherine Reynolds, MD, McGovern Medical School, Department of Emergency Medicine, The University of Texas Health Science Center of Houston.)

A 46-Year-Old Male Who Presents Due to His Defibrillator Firing