A Patient with Right-to-Left Shunt Atrial Septal Defect Without Pulmonary Hypertension

Abstract

We present a case of atrial septal defect (ASD) in a 27-year-old young woman who presented with a right-to-left shunt despite normal pulmonary artery pressure without anomalous pulmonary venous drainage and only mild tricuspid regurgitation (TR), but it was associated with right ventricular dysfunction. Considering the dysfunction of the right heart and significant dilatation of the tricuspid annulus, the surgeon still decided to repair ASD and perform tricuspid valvuloplasty. The surgery lasted approximately three hours, and the whole procedure was smooth and uneventful. Her postoperative recovery was uneventful and discharged in good condition. The occurrence of right-to-left (R-L) shunting in patients with ASD is uncommon and is usually an ominous sign, heralding irreversible pulmonary hypertension (PH). There is little information about similar shunts for patients without PH and tricuspid regurgitation (TR), and the majority of these patients have an anatomic anomaly that favors this type of shunt. ASD with R-L shunt without Eisenmenger physiology is rarely reported and may be underestimated due to difficulty in its diagnosis. Intraoperative transesophageal echocardiography (TEE) examination should not only focus on cardiac structure but also the evaluation of ventricular function. Right-to-left shunt is possible in ASD patients even with normal pulmonary arterial pressure.