I would not know the answer to this question, as I do not do this procedure. You should email Stan Perry or another experienced interventionalist for a more experienced opinion.

I would advice joint approach with a surgeon standing by.

No longer.Balloon stretching may destroy the edges.TEE size+2mm would be the device size I choose.

Pediatric interventionalists are moving away from balloon sizing, even though it is not standard practice yet. Reasons include increasing concern about erosions and the perception that balloon sizing leads to choice of larger devices. Now, the practice is very variable. Even within my institution (3 interventionalists), we differ in our practices. In general, the selection of device size is made based on various factors - patient's size, appearance of defect, variation between ASD diameters in long-axis and short-axis, thickness of the rims on each side, length of atrial septum, etc. TEE size + 0 to 4 mm is being used. There have been times, when we have chosen the same size as the TEE measurement especially in an younger child. When we reviewed our data on predicting balloon-stretch diameter from TEE diameter, they were mostly ~4 mm above the TEE diameter (with some exceptional cases where stretch diameter was much higher than TEE diameter).

The use of the balloon measurement of the stretched diameter of SASD is preferably because the edges of the defect in some cases can be very soft, and if implant the prostheses just +2mm to TEE diameter it can be embolized. To avoid damage of the edges of the asd it is necessary to inflate the balloon up to slight appearance of the waist, not more.

It depends a lot of the morphology of the ASD. In typical central located ASD´s the ballon sizing is optional because of the mentioned technical difficulties and the problem that the device will be larger than necessary. In very soft thin rims it can be helpful to "interrogate" the stiffness of the septum. Important is to limit the maximal diameterof the device in the short axis between aorta and posterior wall of the atrium and in the 4 chamber view to prevent erosions of the atrial roof. In huge ASDs I prefer to size the defct form the native diameters and oversize the device 3-5mm.

I think it is necessary to accentuate which type of ASD device we are using and in which type of ASD. Because each of them has his own indication, contraindication and limitations for use regarding the size of ASD and its rims. Let say for Amplatzer devices with the size of 4-10mm the LAD (left atrial disc) is over the waist for 6 mm and RAD is over the waist for 4 mm. And for Amplatzer ASD device in size from 11 to 40 mm the LAD is over the waist for 8mm and RAD - for 5 mm. It is mean that if we have insufficiency of some of the rims around the ASD we has risk for interference of the margin of the disc of the device with surrounding ASD edge's heart structures. It is recommended that in case of insufficiency of one of the rims the TC ASD occlusion can be provided, in case of insufficiency of two rims it is under debate and depend of degree of insufficiency (3-5 mm, or less than 3 mm or complete absence) and the insufficient rim localization, in case of insufficiency of 3 or more rims according to my experience it is better do not provide TC ASD occlusion with the Amplatzer device. What regards to other devices and other types of ASDs - all of them has own indication, contraindications and limitations. It is better to keep along with recommendations to avoid the complications.

Flow stop technic is better

Dear Dr. Mese, I agree with you, but in large ASD the stop flow and the extended diameter cannot be obtained. What is your conduct in this case?

As a Pediatric cardiolog I prefer to send it to surgeon

This is a not wrong conduct, but in many these cases successful percutaneous treatment is possible.

Dr.Jacob! Could you say me please, what exact diameter has this ASD by TTE or TEE and what sizes are its rims. Also please give me any information what type of ASD occluder you are going to use? Also please inform regarding patient's age.

Dear Armine. It is not a case. This is a generic question about large ASD with 30mm or more. In these case I performe the occlusion as descrided in my coment bellow the question. In these cases I prefer the Occutech device that is more soft than Amplatzer or CERA devices that also I use. The other devices I think inadequte for these cases.The use of big devices is possible only in adult patients.

I followed the answers on this question with interest. Since several years we do not balloon size ASD's anymore and our results tend to be superior compared to the balloonsizing era (probably also positively influenced by increasing experience and improved material). We use the colour flow width at the septum as "stretched" diameter and add 2 mm if the septum is firm and 4 mm is the septum is thin. If your ASD is 30 mm or larger, you probably should not be too reluctant to oversize your device respecting the total septum length though. We carefully evaluate the presence of a posteroinferior rim, as in our experience absence of this rim is the only predictor of embolization. Moreover, we try not to exceed the total septal length with our device chosen. In large ASD's we prefer the Occlutech device, which due to its rotating and angulating attach mechanism is easier to position correctly without the need for complicated techniques.

Just to add another perspective. We have looked at our 107 patients, several years ago (2001, unpublished data) during US trial of Amplatzer device. Balloon-stretch diameter (we used to create a waist in the balloon those days) was ~4-5 mm larger than TEE diameter (by 2D, not color). This is similar to few other formulas published - by Dr. Rao and Dr. Hellebrand (each independently). I still use this measure, without routine balloon sizing - adding ~4 mm to the TEE diameter by 2D. There are certainly issues with parallelax error during measurement. One should use some judgement in assessing the accuracy of the measurement(s), regardless of the method. This is similar to what Dr. de Wolf has described. As pointed out earlier, device selection is altogether different for Helex device. (Don't have experience with other ASD devices, not approved in US).