A Humongous Atrial Septal Defect

Our patient was a 74-year-old male who presented to the emergency department as a case of obstructed inguinal hernia and was planned for urgent surgery. He was evaluated by the department of cardiology as a part of presurgical workup. He had a history of mild breathlessness on exertion for the last 10–15 years which he attributed to his chronic smoking status and was never worked up for this. On examination, he had a wide-fixed split-second heart sound with a loud P2 component. Electrocardiogram revealed right bundle branch block pattern with left anterior hemiblock [Figure 1a]. Chest X-ray was suggestive of cardiomegaly with pulmonary plethora and prominent proximal pulmonary arteries [Figure 1b]. Peripheral arterial saturation was 97%.Figure 1: (a) Electrocardiogram revealed right bundle branch block pattern with left anterior hemiblock. (b) Chest X-ray was suggestive of cardiomegaly with pulmonary plethora and prominent proximal pulmonary arteries. (c) Two-dimensional echocardiography demonstrated a humungous 76 mm ostium secundum atrial septal defect. (d) Ostium secundum atrial septal defect with left-to-right shunt. (e) Pulmonary artery systolic pressure of 77 mm of Hg + right atrial pressure indicating severe pulmonary artery hypertension. (f) Moderate-to-severe mitral regurgitationTwo-dimensional echocardiography demonstrated a humungous 76 mm ostium secundum atrial septal defect (ASD) [Figure 1c], with left-to-right shunt [Figure 1d] and resultant dilatation of the right atrium and ventricle. There was a moderate-grade tricuspid regurgitation with a pulmonary artery systolic pressure of 77 mm of Hg + right atrial pressure [Figure 1e], indicating severe pulmonary artery hypertension. There was moderate-to-severe mitral regurgitation with mitral valve prolapse [Figure 1f]. The right and left ventricular functions were normal. This is a rare case with a triad of unusual findings. First, according to our review, this is the largest ASD ever reported. This humungous ASD is postulated to be due to concomitant stretching of the ASD margins by the enlarging atria. Atrial size is enlarged due to the combination of severe mitral regurgitation (left atrium), left-to-right shunt (right atrium), and atrial fibrillation (both atria).[1] Second, it is a large ASD presenting unusually late.[2] Third, mitral regurgitation leading to the elevation of left-sided pressures is postulated to contribute to persistent left-to-right shunt despite severe pulmonary artery hypertension. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.