A new technique for sizing of atrial septal defects.
This article evaluates a new compliant balloon catheter for sizing of Atrial Septal Defects (ASDs) in vitro and in vivo using X-ray and echo measurements. A phantom consisting of a plastic plate with 17 circular holes varying from 8 to 30 mm was used to determine the accuracy of the measurements. The catheter has a 7 Fr shaft with a double lumen. The balloon is made from a 0.002" plastic membrane. Four platinum marker bands on the shaft of the catheter allow radiographic measurements. The balloon catheter was placed through various holes of the phantom and inflated with 38% contrast medium. X-ray measurement by video and cine recording were performed and compared with the true measurement of the model. The study was carried out in a double blind fashion. For echo measurements, the plastic model was immersed in a water bath. The balloon was inflated with water and measured in a long-axis view. The actual diameters were compared with the measurements obtained by video, cine, and echo recordings. One young pig with a surgically created ASD was used for in vivo measurement. The balloon catheter was passed through the ASD over an exchange wire, inflated with diluted contrast medium until a waist was observed, which was measured by video and cine techniques. The animal was euthanized, and the defect was measured by a tapered measuring probe. The difference between the actual size and measurements obtained by video recordings was 0.54 +/- 0.30 mm, by cine 0.62 +/- 0.20 mm, and by echo measurements 0.60 +/- 0.43 mm. All measurements were less than 1 mm in error except for four measurements (<1.5 mm). A strong correlation was present between each two groups (r = 0.99, P < 0.0001). In the in vivo study, the size of the video and cine recordings (14.2 and 13.9 mm, respectively) were very closer to the actual size (14 mm) as measured by a probe in the postmortem specimen. The new balloon catheter provides a more rapid and precise determination of the stretched diameter of atrial septal defects. It eliminates the error of pulling a catheter through the communication. This new technique should be of benefit to all investigators using septal occlusion devices and will facilitate the selection of the properly sized Amplatzer septal occluder.
Gu
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Department of Radiology, Fairview University Medical Center, Minneapolis, Minnesota 55455, USA.
Han
Y M
YM
Berry
J
J
Urness
M
M
Amplatz
K
K
D000818:Animals; D002404:Catheterization / Q000379:methods*; D002932:Cineangiography; D006344:Heart Septal Defects, Atrial / Q000628:therapy*; D008422:Materials Testing; D019736:Prostheses and Implants; D013552:Swine