Hot-Air Balloon Explosion in the Heart

A 16-year old girl experiencing palpitations underwent elective transthoracic echocardiographic examination at a nearby clinic, which showed a 3-cm balloon-like, cystic structure, with inhomogeneous content, adherent to the atrial septum and anchored above the anteroseptal commissure of the tricuspid valve without evidence of flow from the aorta to the right atrium (Figure 1A). On examination, blood pressure (120/70 mm Hg) and heart rate (70 bpm) were normal, but she was advised to limit physical activity. While waiting for scheduled MRI scan, she was admitted to the emergency department for acute vision loss and syncope. At physical examination, the patient presented dyspnea, hypotension (90/50 mm Hg), and tachycardia (130 bpm); a 5/6 continuous, rough murmur was heard over the left precordium. Chest x-ray revealed cardiomegaly and pulmonary congestion. To refine diagnosis of the cardiac mass, the girl underwent transesophageal echocardiographic examination, which demonstrated communication between the aortic root and the previously identified cystic mass, now ruptured in …