A functioning dialysis vascular access is critical to the delivery of lifesaving hemodialysis. Arteriovenous graft (AVG) is a surgically created vascular access used for hemodialysis in patients with end-stage renal disease. AVG thrombosis due to underlying flow-limiting stenosis of the graft vein junction and outflow veins is a common complication. Thrombosed AVG can be treated with thrombolysis combined with percutaneous transluminal angioplasty with good immediate success rates. However, the mid-to-long term patency rates following angioplasty have been suboptimal. Sirolimus drug-coated balloon has been shown to be safe and effective in the salvage of thrombosed arteriovenous graft. The investigators hypothesize that sirolimus drug-coated balloon is non-inferior to stent graft in maintaining the patency of thrombosed AVG that is successfully salvaged. This study is conducted to compare the 6-month access circuit primary patency of thrombosed AVG treated with sirolimus drug-coated balloon versus stent graft.