Atrial Septal Defects
- Secundum atrial septal defect (ASD) with suitable rims of tissue, associated with symptoms of dyspnea, fatigue, or palpitations
- Secundum ASD discovered before the age of 21. In asymptomatic children, the decision to intervene is based on the presence of right heart dilation and significant ASD (>5 mm) that shows no signs of spontaneous closure.
- Secundum ASD with enlargement of right-sided chambers
- Secundum ASD with pulmonary hypertension (pulmonary artery pressure or vascular resistance > 2/3 systemic arterial pressure or systemic vascular resistance, left-to-right shunt ≥ 1.5:1, or evidence of pulmonary artery reactivity with administration of pulmonary vasodilator)
- Secundum ASD and paradoxical embolization
Patent Forman Ovale
- Being evaluated in research to prevent recurrent neurologic events in patients with a cryptogenic stroke and a patent foramen ovale (PFO) in comparison with standard medical therapy
- Being evaluated in research evaluating the role of PFO closure (vs sham procedure) in patients with medically refractory migraine headaches with large right-to- left shunts
- There are no Food and Drug Administration–labeled indications for closure. However, closures have been done for a variety of medical indications in which right-to-left shunting via a PFO has been implicated:
- Cryptogenic stroke
- Migraine headaches
- Platypnea-orthodeoxia (positional right-to-left shunting leading to transient hypoxemia)
- To prevent recurrent decompression illness (the bends) in divers
- Before certain high-risk surgical procedures, such as sitting-up intracranial surgery, liver transplantation, and others, wherein it is common to have the introduction of air into the venous system, which has been associated with hemodynamic and/or neurologic compromise
- Although not reportedly used for such an indication, recurrent high altitude pulmonary edema might be a logical consideration.
- Patients with severe pulmonary hypertension and right heart failure: Closure of a PFO or ASD may exacerbate the right heart failure. Closure of ASDs has been done before the development of right heart failure, however, and is believed to attenuate the progression of the pulmonary hypertension.
- Inadequate rims of tissue to hold the device in place (for ASDs). There should be a minimum of 5 mm of tissue around the majority of the ASD, with the exception of the anteriorly located retro-aortic space, as the aorta will provide a fulcrum for holding onto a device.
- ASD >38 mm
- It is unclear if nickel allergy should be a relative contraindication.
- Pregnancy because of exposure of the fetus to radiation
- Interrupted or occluded inferior vena cava (although alternative access sites may be considered in such circumstances, such as trans-hepatic or jugular vein)
- Coexisting other cardiac condition that would require surgical repair, such as an anomalous pulmonary vein
Note: The procedures for ASD and PFO closure are quite similar, with some overlap in device choices, which may be used for the closure, especially since devices specifically designed to close PFOs are only available as part of research protocols.
- Sterile masks, caps, gloves and drapes
- Routine monitors: blood pressure cuff, ECG, pulse oximeter
- Availability of supplemental oxygen and delivery method (eg, nasal cannula, mask)
- Resuscitation equipment including crash cart, defibrillator, resuscitation drugs, suction, intubation equipment
- Fluoroscopy equipment
- Equipment for IV start for fluid and sedation administration
- Syringe with small-gauge (25- or 30-gauge) needle for subcutaneous infiltration for peripheral IV
- IV catheter
- IV fluid and tubing
- Alcohol or other prep solution
- Tape or transparent sterile dressing to secure IV
- Bandage for IV site after removal
- Lidocaine for subcutaneous administration (0.5%-2%)
- Several syringes
- A bowl of heparinized saline
- Access sheaths for femoral veins: one 8F sheath for access to the defect and a second 8F or 9F sheath (if intracardiac echocardiography is to be used).
- Standard 0.036” J-tipped guidewire
- 6F multipurpose catheter
- An appropriately sized balloon for measuring the defect size. These come in 18 mm, 24 mm, and 32 mm diameters, which should be chosen based on the estimate of the defect size seen on pre-procedure echocardiography (especially transesophageal echocardiography [TEE]) or cardiac magnetic resonance imaging. The use of a balloon is optional but useful for PFO closures
- An appropriately sized, specifically designed transseptal sheath (with dilator), depending on the type and size of the device to be delivered. These range in size from 6F to 12F. A three-dimensional curved transseptal sheath may be used in some circumstances when rotation of the catheter is necessary to orient the device more suitably.
- A bowl with contrast to fill the balloon
- A pressure manifold is optional, as is other equipment for performing a right heart catheterization or for measuring oxygen saturation in right heart chambers.
- An intracardiac echocardiography (ICE) or transesophageal echocardiography (TEE ) probe. An echocardiography console with a technician or sonographer and an echocardiographer if TEE is being used. For the purposes of this demonstration, ICE will be used.
- An appropriately sized closure device, which is often chosen during the procedure, so an assortment of device sizes should be available.
- Large sized snares, larger sheath sizes (14F), and suture closure devices in case of device embolization
- Parenteral heparin
- Parenteral antibiotics (cefazolin or vancomycin for patients who are allergic to penicillin), typically 1 g IV
- Pressure dressing for femoral vein access site
- Typically, venous access is obtained via the femoral veins. If ICE is done, two femoral venous sheaths may be placed—either one in each vein or both in the right femoral vein. Vascular access for catheter ablation via the femoral vein is described here. The femoral vein is located in the groin just medial to the femoral pulsation below the inguinal ligament. The vein is accessed medial to the pulsation of the femoral artery, 1 cm below the inguinal ligament.
- Ostium primum defects occur low in the atrial septal wall.
- Ostium secundum defects occur at the site of the fetal fossa ovalis.
- Sinus venosus defects occur near the openings of the superior and inferior vena cavae.
- Coronary sinus septal defects: In the rarest of ASDs, the roof of the coronary sinus is missing, and blood can enter the coronary sinus from the left atrium and pass into the right atrium.
- The foramen ovale is a normal fetal communication between the overlapping layers of the primum and secundum portions of the atrial septum. Failure of the layers of the septum to fuse may allow the flap of septum primum that normally covers the fossa ovalis to open transiently during pressure changes in the left and right atria. This can permit blood flow in either direction.