Original Studies Midterm Follow-Up Results of Transcatheter Treatment in Patients With Unroofed Coronary Sinus Jou-Kou Wang, 1 * MD, Shy-Jye Chen, 2 MD, Jui-Yu Hsu, 1 MD, Su-Man Lin, 3 MD, Ming-Tai Lin, 1 MD, Shuenn-Nan Chiu, 1 MD, Chun-An Chen, 1 MD, and Mei-Hwan Wu, 1 MD Objective: We present the midterm results of transcatheter treatment of unroofed coronary sinus (CS) using the Amplatzer septal occluder. Background: The unroofed CS is a rare atrial septal defect communicating the left atrium and CS. Surgery has been the mainstay of treatment. Methods: In a 4.5-year period, nine patients (five males) with ages ranging from 26 to 69 years (median 39 years) diagnosed with an unroofed CS but without a persistent left superior vena cava (LSVC) underwent trans- catheter treatment. Computerized tomography (CT) was performed in eight patients. Transesophageal echocardiography (TEE) was used to monitor the procedure. Results: The mean Qp/Qs ratio was 2.4 6 1 and mean systolic pulmonary artery pressure was 35 6 19 mm Hg. An Amplatzer septal occluder was deployed in all nine patients. The device was implanted in the defect in one patient and at the CS ostium in the other eight patients. The median device size used was 22 mm (16–28 mm). The left disc her- niated into the CS in the single patient in whom the device was implanted within the defect. All patients were available for the 3-month follow-up. None had a residual shunt on the 3-month follow-up echocardiography. One patient died of a stroke 4.5 months after the procedure. At mean follow-up of 42.6 6 18.3 months, symptomatic improvement was documented in the remaining eight patients. All eight patients had an O 2 saturation above 96%. Conclusion: Transcatheter treatment for unroofed CS without persistent LSVC using Amplatzer septal occluder is safe and feasible. V C 2013 Wiley Periodicals, Inc. Key words: unroofed coronary sinus; transcatheter treatment; Amplatzer septal occluder INTRODUCTION The unroofed coronary sinus (CS) allows a left-to- right shunt between left atrium and CS through the defect located on the roof of the CS. Hemodynami- cally, it mimics the atrial septal defect with a left-to- right shunt at the atrial level. It is a rare form of interatrial communication and is frequently associated with persistent left superior vena cava (LSVC) [1–5]. Surgery has been the mainstay of treatment [1,6,7]. Recently, transcatheter intervention using devices has been regarded as a procedure of choice in the treatment of the secundum type atrial septal defect [8]. This tech- nique has been applied in the closure of the unroofed CS in limited case reports [9,10]. We report our initial and mid-term follow-up results of transcatheter treat- ment of the unroofed CS in nine patients without per- sistent LSVC. 1 Department of Pediatrics, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan 2 Department of Radiology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan 3 Department of Anesthesiology, National Taiwan University Hospi- tal, College of Medicine, National Taiwan University, Taipei,Taiwan Conflict of interest: Nothing to report. Contract grant sponsor: National Science Council; Contract grant number: 94-2314-B-002-148. *Correspondence to: Jou-Kou Wang, Department of Pediatrics, National Taiwan University Hospital, No. 7 Chung-Shan South Road, Taipei, Taiwan. E-mail: jkww@ntuh.gov.tw Received 13 April 2012; Revision accepted 25 August 2013 DOI: 10.1002/ccd.25185 Published online 00 Month 2013 in Wiley Online Library (wileyonlinelibrary.com) V C 2013 Wiley Periodicals, Inc. Catheterization and Cardiovascular Interventions 00:00–00 (2013)