Introduction: Atrial fibrillation (AF) is the most common cardiac arrhythmia, occurring primarily in individuals with known risk factors such as advanced age, heart failure, and coronary artery disease. Cannabis use produces several cardiovascular changes resulting in proarrhythmic effects on the heart.

Case Report: A 38-year-old woman with no significant past medical history presented to the emergency department (ED) complaining of palpitations with associated shortness of breath occurring after smoking marijuana. She was found to be in AF. Evaluation in the ED and during hospitalization found no cardiac or metabolic conditions that predisposed to AF. The AF resolved within three hours of onset
without intervention.

Conclusion: Cannabis use should be considered as a possible etiology of new-onset AF, especially in relatively young patients with no other predisposing risk factors.

Lemierre syndrome is a rare condition characterized by a septic thrombophlebitis of the internal jugular vein with septicemia and metastatic foci of infection. It typically occurs as the result of an infection in the head and neck, most commonly pharyngitis. For reasons that are unclear, the incidence of Lemierre syndrome has been increasing over the past 15 years. Diagnosis of Lemierre syndrome is often delayed, and identification of internal jugular vein thrombosis is often the first indicator of its presence. We report a case of Lemierre syndrome associated with a laryngeal carcinoma.

Colpocephaly is a form of congenital ventriculomegaly characterized by enlarged occipital horns of the lateral ventricles with associated neurologic abnormalities. The diagnosis of colpocephaly is typically made in infancy. Its diagnosis in adulthood without associated clinical symptoms is exceptionally rare. We report a case of colpocephaly diagnosed incidentally in an adult without neurologic abnormalities in the emergency department. To our knowledge, this is only the ninth reported case in an asymptomatic adult and the first to be described in the emergency medicine literature.