eMedicine Specialties > Cardiology > Congenital Heart Disease in the Adult

Atrial Septal Defect: Treatment

Author: Larry W Markham, MD, Assistant Professor of Pediatrics and Medicine, Vanderbilt University School of Medicine
Coauthor(s): Marc G Cribbs, MD, Fellow, Department of Pediatric Cardiology, Vanderbilt University Medical Center
Contributor Information and Disclosures

Updated: Jan 21, 2010

Treatment

Medical Therapy

Atrial septal defect (ASD) is a disorder to be addressed surgically or through interventional catheterization. No specific or definitive medical therapy is available. However, patients with significant volume overload or atrial arrhythmias may require specific drug therapy.

Surgical Therapy

Criterion standard

The criterion standard in the treatment of atrial septal defect (ASD) is direct closure of the defect by using an open approach with extracorporeal support. John Gibbon performed the first successful ASD closure by applying this method in 1953. Surgical techniques and equipment have since improved to the point that the mortality rate from this repair approaches zero.

In the usual procedure, a median sternotomy incision is made, and the sternum is split in the midline. Direct arterial and double venous (superior vena cava and inferior vena cava) cannulation are performed. By applying cardiopulmonary bypass, the aorta is clamped, and the heart is arrested with a cardioplegia solution. The caval snares are tightened, and the right atrium is opened. Most secundum defects can be closed by using a direct continuous suture of 3-0 or 4-0 polypropylene (Prolene).

Caution must be taken when large defects are directly closed because this closure can distort the atrium. Large defects that rise superiorly can distort the aortic anulus if closed directly. These ASDs are best closed by using autologous pericardium or synthetic patches made of polyester polymer (Dacron) or polytetrafluoroethylene (PTFE). Care must be taken to completely remove any air or debris from the left atrium and ventricle before cardiopulmonary bypass is discontinued. Temporary pacing wires are left in place on the right ventricle before the chest is closed over the drains.

In an ostium primum defect, surgical closure is more complicated. The patch must be attached to the septum at the juncture of the mitral and tricuspid valves. Mitral valve repair, including closure of the cleft mitral leaflet and, possibly annuloplasty, may be necessary to correct or prevent mitral insufficiency. In rare cases, mitral valve replacement may be required.

In a sinus venosus defect, partial anomalous pulmonary venous return is typical. One or more of the pulmonary veins primarily drains into the right atrium. The ASD must be patched in such a way as to ensure that the anomalous pulmonary venous drainage is diverted into the left atrium. This patching may be simple or complex, depending on where the anomalous drainage enters. Many innovative techniques have been developed to redirect pulmonary venous flow, and the surgeon should be familiar with several approaches. Pulmonary venous return must not be compromised with the redirection because this invariably causes localized pulmonary venous hypertension.

Minimally invasive approaches

In recent years, minimally invasive approaches to the repair of ASD have garnered significant interest. In most cases, the size of the incision is simply decreased with different approaches to cardiopulmonary bypass. Examples include partial or full submammary skin incision, hemisternotomy, and limited thoracotomy. The goal is to improve better cosmetic results because these approaches are not associated with decreased morbidity or mortality.

Percutaneous transcatheter closure

In recent times, secundum ASD have been closed by using a variety of catheter-implanted occlusion devices rather than by direct surgical closure with cardiopulmonary bypass. These devices are placed through a femoral venous approach and are deployed like an umbrella to seal the septal defect. These devices work best for centrally located secundum defects. Although surgical closure is associated with low morbidity and mortality and excellent long-term results, sternotomy and cardiopulmonary bypass are required.

Drs King and Mills performed the first transcatheter closure of a secundum ASD in the mid-1970s. William Rashkind pioneered the development of percutaneous ASD closure technique in late 1970s. Jim Lock developed the clamshell method in 1989. Around the same time, Sideris started clinical trials with buttoned device.

Although many devices have been studied, over the last few years, 4 major devices have become available: CardioSEAL (NMT Medical, Inc; Boston, Mass), Amplatzer septal occluder (ASO) (AGA Medical Corporation; Golden Valley, Minn), HELEX septal occluder (Gore Medical [WL Gore & Associates, Inc]; Flagstaff, Ariz), and Sideris patch (Custom Medical Devices; Amarillo, Tex). The ASO is currently the most widely used device because it is easy to implant and allows closure of large orifices with excellent success rates in most cases. It was first used in humans in 1995. Selection of a particular device is difficult because no randomized trials have been conducted. Furthermore, devices are currently not amenable to percutaneous closure of ostium primum and sinus venosus defects.

With this technique, the static diameter of the defect is first assessed by using TEE, and the stretched diameter is then measured with a sizing balloon to select the proper diameter of the device. The margins of the orifice must be wide enough to accommodate the edges of the closing device. TEE has been the mainstream technique for device sizing, positioning, and deployment, but it can cause discomfort. In addition, airway protection and general anesthesia are required. Intracardiac echocardiography has been used for the same purpose.

Transcatheter closure of ASDs is now established practice at most cardiac centers. It is proven safe in experienced hands, it is cost-effective, and it favorably compares to surgical closure with successful implantation rates of more than 96%. Transcatheter closure has been associated with fewer complications, shortened hospitalization, and reduced need for blood products.

Furthermore, transcatheter closure appears to have additional benefits regarding hemodynamic improvement compared with surgery. In one study, transcatheter closure with ASO improved the left atrial volume index, the left ventricular myocardial performance index, and the right ventricular myocardial performance index.5 The last was unimpressive after surgery, possibly because of cardiopulmonary bypass.

Another group compared atrial function in 45 patients with a mean age of 9 years after surgery and after percutaneous closure by using strain-rate imaging.6 They found that both atrial functions were preserved after transcatheter closure, whereas the same was not seen after surgery. A potential explanation was that an atriotomy scar might have negatively influenced right atrial functio, whereas perioperative hypoxia or intraoperative myocardial damage might have altered the deformation properties of the left atrium.

Postoperative Details

Postoperative management after atrial septal defect (ASD) repair is usually standard. Patients are expected to be awake and often extubated shortly after the operation. Drainage tubes are removed from the chest the first morning after surgery, and, except when rhythm problems occur, the pacing wires are removed shortly thereafter. Most patients can eat and ambulate without difficulty on the first or second postoperative day, and most are discharged by the third or fourth postoperative day. After transcatheter occlusion, patients are generally discharged the next day. Six months of treatment with aspirin with or without clopidogrel is recommended to prevent thrombus formation.

Follow-up

Surgical follow-up care is maintained until the patient's wounds are completely healed and normal activities are resumed. This period rarely exceeds 1-2 months. All complications must be clearly resolved before the patient is discharged from surgical care.

Obtain at least 1 follow-up echocardiogram to confirm complete closure of the ASD. A cardiologist with congenital experience should continue patient care to monitor for recurrence of the shunt and to ensure that the patient has returned to normal activities and cardiac function. For most patients, a yearly appointment after the immediate postoperative period is adequate, in large part to follow and evaluate for arrhythmia complications.

For excellent patient education resources, visit eMedicine's Heart Center. Also, see eMedicine's patient education article Palpitations.

Complications

Surgery may be associated with a long-term risk of atrial fibrillation or flutter. The risk of infective endocarditis exists during the first 6 months after surgery. The following complications are also associated with atrial septal defect (ASD):

The following complications are specifically associated with the use of transcatheter occlusion devices:

  • Device embolization and malpositioning: The incidence significantly varies among devices and is related to operator experience and appropriate case selection. With experienced clinicians, the incidence is less than 1%. Device embolization and malpositioning happens as a result of inadequate sizing of the defect or incorrect device placement.
  • Postimplantation arrhythmias: The incidence is 1-4% and varies from first- to third-degree AV block and atrial fibrillation. These arrhythmias are usually short-lived and do not require medical treatment. Patients who develop complete heart block are typically hemodynamically stable and do not require pacing. The incidence of arrhythmia appears to be related to the size of the device.
  • Thrombus formation: A study of 1000 patients was performed to investigate the incidence of thrombus by performing TEE at 4 weeks and 6 months after the procedure.7 The overall incidence was 1.2%; 70% were found at 4 weeks. The lowest incidence was with ASO. Thromboembolic events were seen in 20% of patients with thrombus. In 80-85%, thrombus resolved with heparin and warfarin. Risk factors for thrombogenesis on the device were the type of device, postprocedural atrial fibrillation, incomplete neoendothelialization of the surface of the device, insufficient antithrombotic treatment, and previously undiagnosed hypercoagulability disorders (including aspirin resistance and persistent interatrial septal aneurysm). For prophylaxis, aspirin given for 6 months is a common practice. When combined with clopidogrel, no thrombus was noted at 4 weeks and 6 months in one study of 37 patients.8
  • Cardiac perforation: The incidence is 0.1-0.4% for various devices. Oversizing of the device and deficient anterosuperior rims are risk factors for perforation. Technique-related perforation during the procedure is amenable to intervention. Device-related perforations occur after technically adequate procedure in approximately 70% of patients after hospital discharge. A retrospective review of 24 patients revealed that all presented with chest pain, shortness of breath, hemodynamic collapse, or sudden death. About 76% were female patients, and 70% of the perforations were late. If pericardial effusion is present on predischarge echocardiography, the patient should be hospitalized for 24-48 hours of observation and follow-up echocardiography.9
  • Device erosion: Erosion of septal occluder devices occurs in 0.1-0.15% of implants.10 Nearly all erosions occur at the dome of atria near the aortic root. Risk factors are a deficient aortic rim and/or superior rim and use of an oversized device. Aortic–right atrial fistula may be the consequence. Although device erosion is rare, the mortality rate is 10%.
  • Increased levels of cardiac troponin I: Transcatheter closure induces minor myocardial lesions, the extent of which depends on the size of the ASO. The patient's age is not a factor.11
  • Residual shunts: As many as 20% of patients may have a residual shunt persisting for 24 hours after the procedure; >90% of such residua are small. During follow-up, the incidence approaches 0% at 3 years for most series.12,13
  • Other complications include pericardial effusion, transient ischemic attack, and sudden death.

More on Atrial Septal Defect

Overview: Atrial Septal Defect
Workup: Atrial Septal Defect
Treatment: Atrial Septal Defect
Follow-up: Atrial Septal Defect
Multimedia: Atrial Septal Defect
References
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Further Reading

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Keywords

atrial septal defect, atrial septum defect, ASD, atrial septal defect repair, atrial septal defect closure, atrial septal defect surgery, atrial septal defect symptoms

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Contributor Information and Disclosures

Author

Larry W Markham, MD, Assistant Professor of Pediatrics and Medicine, Vanderbilt University School of Medicine
Larry W Markham, MD is a member of the following medical societies: American Academy of Pediatrics
Disclosure: Nothing to disclose.

Coauthor(s)

Marc G Cribbs, MD, Fellow, Department of Pediatric Cardiology, Vanderbilt University Medical Center
Marc G Cribbs, MD is a member of the following medical societies: American Heart Association, American Medical Association, and Christian Medical & Dental Society
Disclosure: Nothing to disclose.

Medical Editor

Park W Willis IV, MD, Sarah Graham Distinguished Professor of Medicine and Pediatrics, University of North Carolina at Chapel Hill School of Medicine
Park W Willis IV, MD is a member of the following medical societies: American Society of Echocardiography
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

Steven J Compton, MD, FACC, FACP, Director of Cardiac Electrophysiology, Alaska Heart Institute, Providence and Alaska Regional Hospitals
Steven J Compton, MD, FACC, FACP is a member of the following medical societies: Alaska State Medical Association, American College of Cardiology, American College of Physicians, American Heart Association, American Medical Association, and Heart Rhythm Society
Disclosure: Nothing to disclose.

CME Editor

Amer Suleman, MD, Consultant in Electrophysiology and Cardiovascular Medicine, Department of Internal Medicine, Division of Cardiology, Medical City Dallas Hospital
Amer Suleman, MD is a member of the following medical societies: American College of Physicians, American Heart Association, American Institute of Stress, American Society of Hypertension, Federation of American Societies for Experimental Biology, Royal Society of Medicine, and Society of Cardiac Angiography and Interventions
Disclosure: Nothing to disclose.

Chief Editor

Park W Willis IV, MD, Sarah Graham Distinguished Professor of Medicine and Pediatrics, University of North Carolina at Chapel Hill School of Medicine
Park W Willis IV, MD is a member of the following medical societies: American Society of Echocardiography
Disclosure: Nothing to disclose.

 
 
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