Acute onset of extreme shortness of breath.

A 33-year-old male presented via ambulance to the emergency department (ED) with extreme shortness of breath. A 12-lead electrocardiogram showed a heart rate of 158 beats/minute and atrial fibrillation with frequent runs of right bundle branch block-type aberrant conduction. Notable labs included a brain natriuretic peptide (BNP) level of 1167 pg/ml (<100pg/ml) and Troponin I of 1.23 ng/ml (<0.04ng/ml). Chest X-ray revealed bibasilar interstitial opacities interpreted as pulmonary edema. Chest auscultation was difficult due to obese body habitus, but heart sounds were described as distant and diaphoresis was noted. Bedside echocardiogram revealed severe mitral regurgitation. He became hypoxemic and required emergent endotracheal intubation. During intubation, he became bradycardic and entered pulseless electrical activity. Despite aggressive resuscitative protocols, the patient was declared dead within four hours of his arrival in the ED. Medical history was pertinent for morbid obesity and hypertension, as well as nonischemic cardiomyopathy characterized by recent (five days prior) left and right heart cardiac catheterization without ventriculography, echocardiogram findings of moderate pulmonary hypertension with no coronary artery disease, and a ventricular ejection fraction documented at 20%. Postmortem toxicology was subsequently shown to be negative. Full, unrestricted autopsy permission was granted under coroner authorization.