Closure of Atrial Septal Defect with Helex device

  • Information for PARENT / GUARDIAN

    Dear Parent,

    You have already been informed that your child has an Atrial Septal Defect (ASD) which needs to be repaired. In the past the only way of doing this involved open-heart surgery. This was a major procedure that necessitated heart lung bypass and required several days of hospitalisation. The operation involved a thoracotomy with its attendant pain and subsequent need for wound healing and left a permanent scar on the chest. In some cases blood transfusion was needed and full recovery took a few weeks. Surgery, at the present time, can be accomplished with minimal risk (less than 1%), but because of the obvious discomfort and relatively long recovery period, alternative procedures have been developed.

    Over the last few years it has become possible to close ASDs with a catheter technique, which avoids the need for surgery and requires only a very brief period in hospital. We have carried out more than two hundred procedures at the Royal Children's Hospital with such devices and are now offering the option of using a new device with different features and some important advantages. This device is called the HELEX device. Your child has been selected as a possible candidate for this procedure, because there is considered to be a high likelihood of successful closure with this device.

    The duration of the procedure will be about 1-2 hours. The catheter will be introduced into a leg vein at the groin and X-ray pictures (angiograms) performed to show the defect. An appropriate sized device will be placed in the defect to achieve closure. An Echo probe will be passed through the mouth and placed in the oesophagus to visualise the heart during the procedure.

    Once satisfactory positioning is confirmed the device would be released. After recovery from anaesthesia and 2 hours of bed rest, your child will be able to sit up and walk about. There may be no need to stay in the hospital overnight (many patients can go home on the day of the procedure) but on the following day we will need to repeat an x-ray of the chest and echocardiography to confirm the position of the device. Some bruising and soreness may persist, in the region where the catheter was introduced, for approximately one week. The procedure can be performed under a local anaesthetic, but in small children (and some older patients), the procedure will usually be performed under general anaesthesia.

    Follow-Up Evaluation

    The clinical study requires a follow-up examination at 24 hours, 1 month, 6 months and 1 year. This entails a physical exam, Echocardiography and X-ray of the chest on all visits to ascertain satisfactory closure. During the exam at 6 months your child will also undergo a detailed X-ray (Fluoroscopy) examination of the device, which would be undertaken in the catheter laboratory
    but only takes approximately 15 minutes.

    Advantages of Closure by using a Device

    The primary advantage of this procedure is that it is a non-surgical technique and is an alternative to open heart surgery. The pain of surgery is avoided and, in comparison to several days hospitalisation for surgery, your child will probably be in the hospital for only 1 day. The procedure requires no blood transfusions, and a scar on the chest will be avoided.

    Risks of Closure by using a Device

    The risks of the procedure are very low and similar to those of routine cardiac catheterisation.  These include allergy to X-ray dye, accidental introduction of air or blood clot (embolism) with potential for "stroke", bleeding around introducer sheaths, disturbance to the heart rhythm during the procedure, infection, injury to the artery, vein or nerves in the groin, and perforation of the heart. Each of these problems is very rare and is not likely to be different than with many other heart catheter procedures. Moreover similar problems can occur during open-heart surgery. Probably the main risk, specific to this procedure, is that the device may dislodge and
    not satisfactorily close the defect. If this were to happen an attempt would be made to retrieve the device, by a catheter technique, and a further device could then be positioned, if considered appropriate. If the device cannot be retrieved easily from the heart, your child will need cardiac surgery for its removal and at the same time the ASD would be repaired. It is anticipated that the risks of the procedure would be no greater than with open-heart surgery.

    Device Safety

    The fabric used in the device is similar to that used by surgeons to repair some heart defects.  The wire frame is made of a biocompatible alloy (Nitinol), which has been employed in different kinds of surgical 'implants' over many years. Structural failure of the device has not been encountered in experimental studies. It is not likely to lead to any adverse effect.

    Advantages of the HELEX device

    Compared with other devices the HELEX device is less 'bulky' and contains only a very small amount of metal (Nitinol) that is covered by the fabric material and not in contact with the blood. It is expected that the device will rapidly become covered by natural tissue and will 'heal' into the heart very completely. During the procedure to place the device it is easily retrievable if its position is not satisfactory and even after it has been 'locked' into position it can still be removed with the catheter if it is not satisfactorily closing the defect or is thought to be unsatisfactory for any reason. If this were to be necessary it might be possible to introduce a different / larger device to close the defect, thus avoiding the need for an operation.

    Further Information

    If, at any time, you have any questions, concerns, or wish to discuss this further please contact Dr Geoff Lane on (03) 9345 5712