Antegrade percutaneous closure of membranous ventricular septal defect using X-ray fused with magnetic resonance imaging.

OBJECTIVES

We hypothesized that X-ray fused with magnetic resonance imaging (XFM) roadmaps might permit direct antegrade crossing and delivery of a ventricular septal defect (VSD) closure device and thereby reduce procedure time and radiation exposure.

BACKGROUND

Percutaneous device closure of membranous VSD is cumbersome and time-consuming. The procedure requires crossing the defect retrograde, snaring and exteriorizing a guidewire to form an arteriovenous loop, then delivering antegrade a sheath and closure device.

METHODS

Magnetic resonance imaging roadmaps of cardiac structures were obtained from miniature swine with spontaneous VSD and registered with live X-ray using external fiducial markers. We compared antegrade XFM-guided VSD crossing with conventional retrograde X-ray-guided crossing for repair.

RESULTS

Antegrade XFM crossing was successful in all animals. Compared with retrograde X-ray, antegrade XFM was associated with shorter time to crossing (167 +/- 103 s vs. 284 +/- 61 s; p = 0.025), shorter time to sheath delivery (71 +/- 32 s vs. 366 +/- 145 s; p = 0.001), shorter fluoroscopy time (158 +/- 95 s vs. 390 +/- 137 s; p = 0.003), and reduced radiation dose-area product (2,394 +/- 1,522 mG.m(2) vs. 4,865 +/- 1,759 mG.m(2); p = 0.016).

CONCLUSIONS

XFM facilitates antegrade access to membranous VSD from the right ventricle in swine. The simplified procedure is faster and reduces radiation exposure compared with the conventional retrograde approach.