The St. Jude Amplatzer Atrial Septal Occluder (ASO) has been linked to rare but life-threatening tissue erosions, which may require emergency open-heart surgery. In some cases, erosion can occur many years after the ASO is implanted.
What is the St. Jude Amplatzer ASO?
St. Jude Medical gained FDA approval for the Amplatzer Atrial Septal Occluder (ASO) in December 2001. This medical device is implanted in children and adults with atrial septal defect, which is an abnormal hole between the upper left and right chambers of the heart. The abnormal opening usually results in too much blood flow to the lungs.
The Amplatzer ASO is designed to close a hole in the heart by “sandwiching” it between two metal discs. It is considered a minimally-invasive treatment, because instead of open heart surgery, the device is implanted through a vein in the groin and guided into the heart with a catheter. Once in place, tissue grows over the Amplatzer and closes the hole in the heart.
What is the problem?
October 17, 2013 — Tissue erosion is a rare but life-threatening side effect of the Amplatzer ASO that may require emergency open heart surgery, according to a Safety Communication from the U.S. Food and Drug Administration (FDA).
The FDA warned:
“The device rubbing against the wall of the heart can erode the tissue and create a hole. It can also lead to further scraping or erosion through tissue in the upper chambers (atria) of the heart, primarily in the top of the atria near the aorta. This scraping may also cause separate or simultaneous holes in the aortic root, potentially leading to blood building up in the sac surrounding the heart (cardiac tamponade). If too much blood builds up in this sac, the heart will not be able to work properly.”
How Often Does Tissue Erosion Occur with the Amplatzer Septal Occluder?
Tissue erosion is estimated to occur in 1 to 3 per 1,000 patients who are implanted with the Amplatzer ASO, according to the FDA. Between 2002 and 2011, the FDA received more than 100 reports of tissue erosion associated with the Amplatzer ASO. Several medical journals also reported the side effect.
The FDA is concerned because “This type of device failure has not been seen in similar devices used to treat this condition.” They have asked St. Jude to conduct a study of patients who were recently implanted with the device. The study is designed to estimate the incidence of erosion.
Studies of St. Jude Amplatzer Tissue Erosion
- Catheter Cardiovascular Intervention, December 2004: 28 cases (14 in the United States) involving tissue erosion from Amplatzer ASO; incidence estimated at 0.1%.
- Annals of Thoracic Surgery, May 2011: Case report of an Amplatzer ASO that eroded into the patients aortic root within 4 months, caused congestive heart failure, and had to be removed surgically.
- Catheter Cardiovascular Intervention, October 2013: Report the case of a very late Amplatzer tissue erosion, more than 8 years after the implant.
- And more
FDA Class 1 Recall of St. Jude Amplatzer TorqVue Delivery System
In January 2013, the FDA issued a Class 1 recall for the Amplatzer TorqVue Delivery System, which is used to deliver the Amplatzer Occluder devices into a patient’s heart because the core wires could fracture.
- Cardiac perforation
- Fistula formation
- Scar tissue
- Migration of the Amplatzer
- Congestive heart failure
- Cerebral embolism
- Emergency open-heart surgery