An elderly woman with worrisome weakness: Take a pause to think of blocked PACs.

We present the case of a 93-year-old woman with dementia, with no pertinent cardiac history except for hyperlipidemia, who presented to the emergency department with six months of progressive dysphagia, weakness, and falls. While she had no seemingly cardiac symptoms and or remarkable cardiovascular examination features, the patient's initial electrocardiogram (ECG) showed occasional brief pauses with no atrial or ventricular activity. Computer interpretation of the rhythm was "sinus pause," but upon closer investigation, the true diagnosis was different, but with potential to be equally ominous if not accurately recognized and appropriately managed.