What is iASD and its clinical relevance?  

An iASD is a defect created when a catheter is inserted across the atrial septum, primarily in the ostium secundum region, when performing left heart diagnostic or interventional procedures including: ablations, left atrial appendage occlusion and mitral valve repair or replacement.1,2

The resulting defect in the septum may allow blood to shunt between the left and right atria, either in a left-to-right or right-to-left direction. In some patients, this shunting can be clinically relevant, resulting in potential right heart volume overload or reduced systemic oxygenation.3,4,5

In many patients, the iASD may close on its own over time or have clinically insignificant shunting.6 Clinical studies have shown that larger iASDs are more likely to remain open and cause residual shunting.7

Clinical considerations and FDA approval

Gore has confirmed with the U.S. Food and Drug Administration that iASD closure is within the scope of approved indications for GORE® CARDIOFORM Septal Occluder and GORE® CARDIOFORM ASD Occluder, which include the closure of ostium secundum ASDs.

Gore does not have sufficient data to inform the management of iASDs using septal occluders. Currently, there are no established clinical guidelines or recommendations available for iASD management.

Refer to Instructions for Use at eifu.goremedical.com for a complete description of all applicable indications, warnings, precautions and contraindications for the markets where this product is available. RXOnly

Read Gore's confirmation letter

Clinical decision making

There are no established clinical guidelines on how to manage iASDs or when closure is recommended. Physicians should carefully monitor patients with iASDs and consider the hemodynamic impact of the shunt and clinical presentation when deciding on the necessity and timing of closure.

The decision to close an iASD is at the discretion of a patient’s physician based on patient-specific factors.

Clinical studies of transcatheter edge-to-edge repair of the mitral valve, which utilize a 22 Fr delivery system that crosses the atrial septum, have demonstrated that up to 50% of patients may have a persistent iASD following the index procedure at timepoints up to 6 months post-procedure.8 In some cases patients may show clinical signs that suggest a benefit from closure including larger defects with left-to-right shunting that place a significant volumetric load on the right heart, right-to-left shunting resulting in hypoxemia and a potential concern for paradoxical embolism.9

Gore does not have clinical data to inform clinical decision making associated with iASDs. Closure of iASDs varies across the clinical community, but case studies show that clinical workup is substantially equivalent to the evaluations needed for congenital defect closure decisions.4,5 Patients with left-to-right shunting and signs of right heart volume overload from a persistent iASD present like those with a congenital defect. Other patients may experience acute hemodynamic instability.3,5 In either case, the procedural steps to implant a septal occluder for iASD closure are identical to congenital ASD closure and the mechanism of defect occlusion is the same.

Products related to iatrogenic Atrial Septal Defects (iASD)

  1. Kadado AJ, Islam A. Iatrogenic atrial septal defect following the MitraClip procedure: a state-of-the-art review. Catheterization & Cardiovascular Interventions 2021;97(7):E1043-E1052.
  2. Nagy Z, Kis Z, Géczy T, Temesvari A, Som Z, Borbas S, Breuer T, Molnar D, Foldesi C, Kardos A. Prospective evaluation of iatrogenic atrial septal defect after cryoballoon or radiofrequency catheter ablation of atrial fibrillation-"EVITA" study. Journal of Interventional Cardiac Electrophysiology 2019;56(1):19-27.
  3. Takaya Y, Akagi T, Hara H, et al. Iatrogenic atrial septal defect requiring transcatheter closure following transcatheter mitral valve repair. Circulation Journal 2022;86(11):1740-1744.
  4. Kelly BA, Awdish R, Hegab S. Good fences make good neighbors: How an iatrogenic atrial septal defect can impact the pulmonary circulation. Presented at the American Thoracic Society International Conference (ATS) 2017; May 19-24, 2017; Washington, DC. American Journal of Respiratory and Critical Care Medicine 2017;195. C70.
  5. Nandkeolyar S, Contractor T, Bhardwaj R, et al. A multidisciplinary approach to electrical instability and cardiogenic shock in acute myocardial infarction. JACC: Case Reports 2020;2(13):2053-2059.
  6. Lurz P, Unterhuber M, Rommel KP, et al. Iatrogenic atrial septal defects following transcatheter mitral valve repair and implications of interventional closure. JACC: Cardiovascular Interventions 2021;14(24):2685-2694.
  7. Alkhouli M, Sarraf M, Zack CJ, Holmes DR. Rihal CS.  Iatrogenic atrial septal defect following transseptal cardiac interventions. International Journal of Cardiology 2016;209:142-148.
  8. Schueler R, Öztürk C, Wedekind JA, et al. Persistence of iatrogenic atrial septal defect after interventional mitral valve repair with the Mitraclip system: a note of caution. JACC: Cardiovascular Interventions 2015;8(3):450-459.
  9. Wiktor DM, Carroll JD. ASD closure in structural heart disease. Current Cardiology Reports 2018;20(6):37. 
IFU Consult instructions

Refer to Instructions for Use at eifu.goremedical.com for a complete description of all applicable indications, warnings, precautions and contraindications for the markets where this product is available. RXOnly

INDICATIONS FOR USE IN THE U.S.: The GORE® CARDIOFORM ASD Occluder is a permanently implanted device indicated for the percutaneous, transcatheter closure of ostium secundum atrial septal defects (ASDs). CONTRAINDICATIONS: The GORE® CARDIOFORM ASD Occluder is contraindicated for use in patients: unable to take anti-platelet or anticoagulant medications such as aspirin, heparin, or warfarin; with anatomy where the GORE® CARDIOFORM ASD Occluder size or position would interfere with other intracardiac or intravascular structures, such as cardiac valves or pulmonary veins; with active endocarditis, or other infections producing bacteremia, or patients with known sepsis within one month of planned implantation, or any other infection that cannot be treated successfully prior to device placement; with known intracardiac thrombi.

INDICATIONS FOR USE IN THE U.S.: The GORE® CARDIOFORM Septal Occluder is a permanently implanted device indicated for the percutaneous, transcatheter closure of the following defects of the atrial septum: ostium secundum atrial septal defects (ASDs); patent foramen ovale (PFO) to reduce the risk of recurrent ischemic stroke in patients, predominantly between the ages of 18 and 60 years, who have had a cryptogenic stroke due to a presumed paradoxical embolism, as determined by a neurologist and cardiologist following an evaluation to exclude known causes of ischemic stroke. CONTRAINDICATIONS: The GORE® CARDIOFORM Septal Occluder is contraindicated for use in patients: unable to take antiplatelet or anticoagulant medications such as aspirin, heparin or warfarin; with anatomy where the GORE® CARDIOFORM Septal Occluder size or position would interfere with other intracardiac or intravascular structures, such as cardiac valves or pulmonary veins; with active endocarditis, or other infections producing bacteremia, or patients with known sepsis within one month of planned implantation, or any other infection that cannot be treated successfully prior to device placement; with known intracardiac thrombi.

25CR6003-EN01