This is a proposal, for the first time in Canada, to examine the comparative effectiveness of three commercially available devices (ASO, FSO, and GAO/GSO) for transcatheter closure of atrial septal defects (ASD) in adults using a pilot randomized controlled trial.

The most widely used transcatheter device for ASD closure is the the Amplatzer Septal Occluder (ASO). Two other devices that entered the Canadian market are the Gore Cardioform ASD occluder (GAO) and the Figulla Flexible II Occlutech (FSO) device. There exists a paucity of data on the comparative efficacy and safety of these devices. This is a proposal, for the first time in Canada, to examine the comparative effectiveness of three commercially available ASD devices in an internal pilot randomized trial.

Approximately 60 patients referred for transcatheter ASD closure will be recruited in this study over a period of 15 months from 4 participating centers across Canada. This will be a registry-based randomized controlled trial (RRCT) where patients will be enrolled into one of three arms (ASO, FSO, and GAO/GSO) to compare the effectiveness and safety outcomes of three different ASD closure devices.

Inclusion Criteria:

• ≥18 years old referred for percutaneous (secundum) ASD closure with right atrial and ventricular enlargement; and
• clinically significant left-to-tight shunt (Qp:Qs≥1.5:1), or
• evidence of paradoxical embolism (with a TEE defect >10mm),
• written informed consent

Exclusion Criteria:

• TEE/CCT/CMR defect diameter >30mm,
• rim sizes of < 5 mm to the coronary sinus, inferior vena cava rim, an atrioventricular valve, or the right upper pulmonary vein,
• multiple defects,
• complex congenital heart disease requiring surgical repair within 3 years of device placement,
• Eisenmenger-syndrome,
• recent myocardial infarction PCI/CABG < 6 weeks,
• demonstrated intra cardiac thrombi on echocardiography (especially LA or LAA thrombi), or atrial tumor
• known occluded bilateral femoral veins/IVC,
• pulmonary artery systolic pressure more than half the systemic systolic arterial pressure
• recent pelvic venous thrombosis
• serious comorbidity with life expectancy <3 years (e.g., non-skin cancers not in remission, advanced renal failure serum creatinine >160 umol/L)
• patients whose size or condition would cause the patient to be a poor candidate choice for cardiac catheterization (e.g., too small for echocardiographic imaging probe, catheter size, vascular size, active infection, body weight < 8 kg)
• serious infection in < 6 weeks producing bacteremia (e.g. sepsis), active endocarditis, or any other infection that cannot be treated successfully prior to device implantation (patient must have negative blood cultures off antibiotics for 1 week prior to procedure),
• active GI bleed < 6 weeks,
• bleeding disorder, untreated ulcer, or any other contraindications to aspirin therapy, unless another antiplatelet agent can be administered for 6 months
• previous stroke in the past 12 months,
• documented chronic atrial fibrillation or >2 episodes of documented paroxysmal atrial fibrillation in the last 12 months,
• pregnancy or breastfeeding, plan to become pregnant within the next 6 months, not using an effective method of birth control in premenopausal women,
• documented nickel/titanium allergy, or intolerance to contrast agents.

Patients and outcome assessors will be blinded to the device they receive. Healthcare providers or site coordinators cannot be blinded due to clear differences between devices.