Defibrillator Wire Leads Traversing an Atrial Septal Defect

An implantable cardioverter defibrillator (ICD) is placed in the chest wall of patients who have reduced cardiac function and recurrent episodes of ventricular tachycardia or fibrillation. The purpose of the ICD is to detect life-threatening arrhythmias with subsequent cardioversion to a normal rhythm. Standard positioning of ICD leads are isolated to the right atrium and right ventricle, respectively. This case report documents an incidental but rare finding of an ICD lead traversing a suspected atrial septal defect in a patient with worsening dyspnea and a history of pulmonary embolism. Transthoracic echocardiography revealed what appeared to be a looped right atrial lead within the left atrium traversing the atrial septum, demonstrating an unusual ring appearance artifact. Subsequent imaging by contrast-enhanced computed tomography of the chest and transesophageal echocardiography confirmed the initial transthoracic echocardiographic findings.