Third time lucky: challenging secundum atrial septal defect.

Secundum atrial septal defect is the most common form of interatrial communication. Atrial septal defects can present in young adults with a variety of clinical presentations, including breathlessness on effort, palpitations, or stroke. Clinical heart failure and resting desaturation are both rarely seen in young patients. We present a case of a young man with a secundum atrial septal defect and a diagnosis of constrictive pericarditis, only made after two attempts at surgical correction of the atrial septal defect, with pericardiectomy at the third attempt and subsequent symptomatic improvement.