A Large Retrospective Study to Evaluate Utility of Zephyr Covered Stent in Transcatheter Closure of Sinus Venosus Defects

BACKGROUND: Transcatheter closure (TCC) of sinus venosus defects (SVD) using balloon-expandable covered stents is an emerging alternative to surgery. ZephyrCS (Sahajanand Laser Technologies, Gandhinagar, India) is available in long lengths to suit SVD closure. A recent hybrid design with a short uncovered end intends to prevent left innominate vein and additional high-draining pulmonary vein occlusion. AIMS: Study the procedural success, serious adverse events, stent performance parameters and need for reintervention after SVD closure. METHODS: This retrospective, single-center observational study analysed all consecutive SVD closures using ZephyrCS between January 2022 and December 2025. RESULTS: TCC was attempted in 100 patients with a median age of 33 years (4-73 years). Availability of long stents allowed a single-stent strategy (hybrid in 14) in 79% and elective overlapping stents only in 21%. 79 mm stent length was more frequently used. Additional stents to bail-out embolization, caudal migration, and fabric leak were required in 22%. Median stent shortening was 9%, and recoil was negligible (median 2%). Procedural success was 98%; two embolizations required surgery. 73.5% had no residual shunt at 1-year transesophageal echocardiography. At a median follow-up of 21 months (2-41 months), residual leak warranted two reinterventions. Asymptomatic intraluminal stent thrombosis was noted in 10.2%, and minor insignificant fabric leak in 11.2%. CONCLUSIONS: ZephyrCS is safe, feasible, and effective for SVD closure, with acceptable mid-term outcomes. Long stents and hybrid design are useful for most anatomic variations. Even though minor fabric leak and intraluminal stent thrombus were not clinically significant, they need to be addressed.