Selected Podcast
AMPLATZER PFO Occluder Device
Lowell Satler, MD, discusses the recently FDA-approved AMPLATZER PFO Occluder, including benefits, risks, and best potential candidates for the device. Dr. Satler also explains the implantation procedure, as well as MedStar Heart & Vascular Institute's unique, patient-based approaches to post-surgical care.
Featured Speaker:
Learn more about Lowell Satler, MD
Lowell Satler, MD
Lowell Satler, MD is the Medical Director of the Catheterization Lab at MedStar Heart & Vascular Institute at MedStar Washington Hospital Center.Learn more about Lowell Satler, MD
Transcription:
AMPLATZER PFO Occluder Device
Melanie Cole (Host): The US Food and Drug Administration recently approved the AMPLATZER PFO Occluder Device, which can reduce the risk of stroke in patients who have previously had a stroke believed to be caused by a blood clot that passed through a small hole in the heart and then traveled to the brain. My guest today is Dr. Lowell Satler. He’s the Medical Director of the Catheterization Lab at MedStar Heart and Vascular Institute at MedStar Washington Hospital Center. Welcome to the show, Dr. Satler. What had been done in the past to prevent recurrent, cryptogenic strokes in terms of PFO closures?
Dr. Lowell Satler (Guest): As you know, cryptogenic strokes probably occur in up to 25% of young patients. We don’t know the source of the stroke, and we start to look for different particular abnormalities, one of which is a small hole in the heart known as the patent foramen ovale. When we’ve identified a patient with a cryptogenic stroke and a patent foramen ovale, we thought that it might be best to have the patient on some type of anticoagulant. For many years, anticoagulants were felt to be the treatment of choice even though we had other methods of treating it, such as an AMPLATZER PFO Occlusion Device. Until recently, there was no data to suggest that the AMPLATZER PFO Occluder Device was superior to medical therapy and as a result, the only patients that were treated with a PFO occluder device in the past were patients who could not take medical therapy or who had recurrent strokes on medical therapy. With the recent FDA approval of the PFO occluder device for the treatment of cryptogenic stroke, we now have a different algorithm for treating patients and that we can offer them the PFO occluder device early on in their disease management.
Melanie: What would be some indication for closure with this device? Give us some clinical indications.
Dr. Satler: It would be a young patient with a cryptogenic stroke for the first time. They are usually evaluated with a series of studies. They’re often seen by either their Primary Care Doctors, or a Neurologist, or even a Hematologist. They’ve all presented with a stroke. They have documentation by a CT or MRI of the stroke, and then an evaluation for the source of the stroke is pursued. This usually involves an echo, which will show the presence of a PFO in a certain percentage of these patients.
Once we’ve identified the PFO and it appears anatomically suitable for closure, we can now recommend using this device to close the defect. What the AMPLATZER PFO Occluder does is it closes the PFO and thus blocks blood clots from passing from the right atrium to the left atrium. To place the device, usually, we insert a delivery catheter through a vein in the leg until it reaches the heart. Then we would advance the occluder through the delivery catheter and open the left disk in the left atrium and then the right disk in the right atrium. The position would then separate the PFO Occluder Device from the delivery catheter, and you remove delivery catheter leaving the occluder device permanently implanted in the heart. This is all done with guidance by Echo. We use a special Echo called called Intracardiac Echo to allow placement and delivery of the device. The patient then leaves the cath lab and would recover overnight in the hospital to be discharged the following day.
Melanie: First of all, you mentioned about providers referring to you, and you mentioned Neurologists and Hematologists, so what would cause them to refer?
Dr. Satler: They’re both evaluating patients with strokes of undetermined etiology at first and if they cannot find another source – a common source might be carotid disease, it might be an irregular heart rhythm – if those are not identified, somewhere in the evaluation an Echo is usually performed, which may demonstrate a patent foramen ovale.
Melanie: Let’s compare medical treatment versus this closure device. When you were using medication -- who would not be a candidate for the device?
Dr. Satler: You have to have certain anatomic requirements so the device would actually fit properly, but the recent trial demonstrated the following important findings. This was known as the RESPECT Trial. It took six and a half years to finally show a positive conclusion, but a better way of looking at this is that if a thousand stroke patients were treated with this device, about six of these patients would have an additional stroke within one year, compared to twelve patients who would have an additional stroke if they were just treated with blood thinning medication alone. Another way of saying this is that there would be a 50% reduction in the incidence of stroke.
Melanie: Dr. Satler, then when you’re talking about the procedure itself, tell us about using imaging studies for the patient before and during the procedure.
Dr. Satler: Before, most of the imaging that identifies the defect is either a surface echo, or 2D echo, or a TEE, to better define the septum and the abnormalities in the septum. Once the defect is identified, and if we decide to treat, the device is implanted with a different type of Echo -- it’s called an Intracardiac Echo. This is a small probe that is placed into the right atrium, and it allows us to visualize the entire intracardiac anatomy for the precise placement of the device.
Melanie: And what might be the complications for the occluder?
Dr. Satler: They’re small, but they do exist – perforation of the heart, infection, a blood clot during or after the delivery, and then very rarely, erosion of the device through the heart. There are certain types of patients that we would not treat. It should not be used in patients who have a tumor or a blood clot at the device implantation site, or a blood clot in vessels along the path to the heart, blood vessels that are too small to allow performance of the implant procedure, have a body organ such as a heart muscle, heart valve, or blood vessels that do not permit placement of the required device, have other congenital heart defects, or have an active infection or an untreated infection.
Melanie: Who would be the continuing provider after this procedure?
Dr. Satler: It’s a team approach. It would be the Cardiologist, the Primary Care Physician, and even the Neurologist to monitor for additional events.
Melanie: And what are some of the recommendations for medicational intervention after discharge? How long does a patient need to be on them?
Dr. Satler: We usually have patients on Aspirin and Clopidogrel, or dual antiplatelet therapy for a period of two to three months, after which time, we stop the Clopidogrel. Our main recommendation is that if anyone is going to have any kind of elective procedure, we prefer them to wait for six months. During that first six months, there is healing of the device, and the interlining of the heart covers the fabric of the device. If any type of elective procedure is performed in the early portion of that six months, there is the potential for bacteremia and an infection of the device. We recommend routine SBE prophylaxis for the first six months after the device implant. In general, we try and avoid any kind of dental manipulation for the first six months after the device implant. Certainly in patients who need any kind of dental work we recommend that be performed prior to the device implant.
Melanie: Have you seen any leakage in the implant post-procedure?
Dr. Satler: We achieve over 85 to 90% complete closure of the residual defect, and so there is a small percentage of patients that will still leak after the device is implanted. For those patients, we can either continue them on additional anticoagulants or antiplatelet therapy or in some case we can identify the residual leak and place an additional device.
Melanie: Dr. Satler, do you think other providers are aware of the possibility of referral and the FDA approvals at this point?
Dr. Satler: We have found at this point in time that the recognition of approval of the PFO Occlusion Device is not known in most of the medical communities, both Cardiology, Neurology, Hematology, and even the Primary Care Physicians. Everyone has been used to the fact that the data, until October of 2016, was not strong enough to support the approval, but after the RESPECT trial with a six-year follow-up, the data was strong enough for the FDA to approve it in October.
Melanie: So what would you like to tell other physicians about the AMPLATZER PFO Occluder Device for cryptogenic stroke – give your best advice, what you want other physicians to know about recognizing this approval and looking into this device or referral?
Dr. Satler: Going forward, we now have an effective tool to reduce the likelihood of stroke in patients with cryptogenic strokes that have PFOs. We can effectively reduce the likelihood of recurrent strokes by 50%. It simplifies the patient management as they no longer require lifelong antiplatelet or anticoagulant therapy. Particularly for this young patient population, it allows a less complicated management course.
Melanie: Thank you, so much, Dr. Satler, for being with us today. You’re listening to Medical Intel with MedStar Washington Hospital Center, and for more information, you can go to MedstarWashington.org, that’s MedstarWashington.org. This is Melanie Cole. Thanks, so much, for listening.
AMPLATZER PFO Occluder Device
Melanie Cole (Host): The US Food and Drug Administration recently approved the AMPLATZER PFO Occluder Device, which can reduce the risk of stroke in patients who have previously had a stroke believed to be caused by a blood clot that passed through a small hole in the heart and then traveled to the brain. My guest today is Dr. Lowell Satler. He’s the Medical Director of the Catheterization Lab at MedStar Heart and Vascular Institute at MedStar Washington Hospital Center. Welcome to the show, Dr. Satler. What had been done in the past to prevent recurrent, cryptogenic strokes in terms of PFO closures?
Dr. Lowell Satler (Guest): As you know, cryptogenic strokes probably occur in up to 25% of young patients. We don’t know the source of the stroke, and we start to look for different particular abnormalities, one of which is a small hole in the heart known as the patent foramen ovale. When we’ve identified a patient with a cryptogenic stroke and a patent foramen ovale, we thought that it might be best to have the patient on some type of anticoagulant. For many years, anticoagulants were felt to be the treatment of choice even though we had other methods of treating it, such as an AMPLATZER PFO Occlusion Device. Until recently, there was no data to suggest that the AMPLATZER PFO Occluder Device was superior to medical therapy and as a result, the only patients that were treated with a PFO occluder device in the past were patients who could not take medical therapy or who had recurrent strokes on medical therapy. With the recent FDA approval of the PFO occluder device for the treatment of cryptogenic stroke, we now have a different algorithm for treating patients and that we can offer them the PFO occluder device early on in their disease management.
Melanie: What would be some indication for closure with this device? Give us some clinical indications.
Dr. Satler: It would be a young patient with a cryptogenic stroke for the first time. They are usually evaluated with a series of studies. They’re often seen by either their Primary Care Doctors, or a Neurologist, or even a Hematologist. They’ve all presented with a stroke. They have documentation by a CT or MRI of the stroke, and then an evaluation for the source of the stroke is pursued. This usually involves an echo, which will show the presence of a PFO in a certain percentage of these patients.
Once we’ve identified the PFO and it appears anatomically suitable for closure, we can now recommend using this device to close the defect. What the AMPLATZER PFO Occluder does is it closes the PFO and thus blocks blood clots from passing from the right atrium to the left atrium. To place the device, usually, we insert a delivery catheter through a vein in the leg until it reaches the heart. Then we would advance the occluder through the delivery catheter and open the left disk in the left atrium and then the right disk in the right atrium. The position would then separate the PFO Occluder Device from the delivery catheter, and you remove delivery catheter leaving the occluder device permanently implanted in the heart. This is all done with guidance by Echo. We use a special Echo called called Intracardiac Echo to allow placement and delivery of the device. The patient then leaves the cath lab and would recover overnight in the hospital to be discharged the following day.
Melanie: First of all, you mentioned about providers referring to you, and you mentioned Neurologists and Hematologists, so what would cause them to refer?
Dr. Satler: They’re both evaluating patients with strokes of undetermined etiology at first and if they cannot find another source – a common source might be carotid disease, it might be an irregular heart rhythm – if those are not identified, somewhere in the evaluation an Echo is usually performed, which may demonstrate a patent foramen ovale.
Melanie: Let’s compare medical treatment versus this closure device. When you were using medication -- who would not be a candidate for the device?
Dr. Satler: You have to have certain anatomic requirements so the device would actually fit properly, but the recent trial demonstrated the following important findings. This was known as the RESPECT Trial. It took six and a half years to finally show a positive conclusion, but a better way of looking at this is that if a thousand stroke patients were treated with this device, about six of these patients would have an additional stroke within one year, compared to twelve patients who would have an additional stroke if they were just treated with blood thinning medication alone. Another way of saying this is that there would be a 50% reduction in the incidence of stroke.
Melanie: Dr. Satler, then when you’re talking about the procedure itself, tell us about using imaging studies for the patient before and during the procedure.
Dr. Satler: Before, most of the imaging that identifies the defect is either a surface echo, or 2D echo, or a TEE, to better define the septum and the abnormalities in the septum. Once the defect is identified, and if we decide to treat, the device is implanted with a different type of Echo -- it’s called an Intracardiac Echo. This is a small probe that is placed into the right atrium, and it allows us to visualize the entire intracardiac anatomy for the precise placement of the device.
Melanie: And what might be the complications for the occluder?
Dr. Satler: They’re small, but they do exist – perforation of the heart, infection, a blood clot during or after the delivery, and then very rarely, erosion of the device through the heart. There are certain types of patients that we would not treat. It should not be used in patients who have a tumor or a blood clot at the device implantation site, or a blood clot in vessels along the path to the heart, blood vessels that are too small to allow performance of the implant procedure, have a body organ such as a heart muscle, heart valve, or blood vessels that do not permit placement of the required device, have other congenital heart defects, or have an active infection or an untreated infection.
Melanie: Who would be the continuing provider after this procedure?
Dr. Satler: It’s a team approach. It would be the Cardiologist, the Primary Care Physician, and even the Neurologist to monitor for additional events.
Melanie: And what are some of the recommendations for medicational intervention after discharge? How long does a patient need to be on them?
Dr. Satler: We usually have patients on Aspirin and Clopidogrel, or dual antiplatelet therapy for a period of two to three months, after which time, we stop the Clopidogrel. Our main recommendation is that if anyone is going to have any kind of elective procedure, we prefer them to wait for six months. During that first six months, there is healing of the device, and the interlining of the heart covers the fabric of the device. If any type of elective procedure is performed in the early portion of that six months, there is the potential for bacteremia and an infection of the device. We recommend routine SBE prophylaxis for the first six months after the device implant. In general, we try and avoid any kind of dental manipulation for the first six months after the device implant. Certainly in patients who need any kind of dental work we recommend that be performed prior to the device implant.
Melanie: Have you seen any leakage in the implant post-procedure?
Dr. Satler: We achieve over 85 to 90% complete closure of the residual defect, and so there is a small percentage of patients that will still leak after the device is implanted. For those patients, we can either continue them on additional anticoagulants or antiplatelet therapy or in some case we can identify the residual leak and place an additional device.
Melanie: Dr. Satler, do you think other providers are aware of the possibility of referral and the FDA approvals at this point?
Dr. Satler: We have found at this point in time that the recognition of approval of the PFO Occlusion Device is not known in most of the medical communities, both Cardiology, Neurology, Hematology, and even the Primary Care Physicians. Everyone has been used to the fact that the data, until October of 2016, was not strong enough to support the approval, but after the RESPECT trial with a six-year follow-up, the data was strong enough for the FDA to approve it in October.
Melanie: So what would you like to tell other physicians about the AMPLATZER PFO Occluder Device for cryptogenic stroke – give your best advice, what you want other physicians to know about recognizing this approval and looking into this device or referral?
Dr. Satler: Going forward, we now have an effective tool to reduce the likelihood of stroke in patients with cryptogenic strokes that have PFOs. We can effectively reduce the likelihood of recurrent strokes by 50%. It simplifies the patient management as they no longer require lifelong antiplatelet or anticoagulant therapy. Particularly for this young patient population, it allows a less complicated management course.
Melanie: Thank you, so much, Dr. Satler, for being with us today. You’re listening to Medical Intel with MedStar Washington Hospital Center, and for more information, you can go to MedstarWashington.org, that’s MedstarWashington.org. This is Melanie Cole. Thanks, so much, for listening.