Laboratory Evaluation of Translumbar Embolization of Endoleaks with NBCA

Since the first endovascular repair of an abdominal aortic aneurysm by Parodi in 1990, the problems of incomplete exclusion of the aneurysm and peri-graft leaks have plagued vascular surgeons. The term “endoleak” was first coined in 1996.¹ The decision of when to treat and when to observe endoleaks has been debated in the vascular literature, and many methods of treatment have been described. There are clinical reports describing successful embolization of endoleaks with N-Butyl Cyanoacrylate (NBCA) via a translumbar approach. The study by Barge et al² in the current issue of Vascular Disease Management attempts to shed further light on the treatment of type 2 endoleaks with NBCA. The authors simulated an endoleak using an in-vitro apparatus, creating a model with one entry and two exit vessels. Swine plasma was used to mimic blood. The endpoints of the study were the successful sealing of the endoleak, and ease in removal of the catheter or needle from the sac after injection of NBCA. NBCA glue successfully sealed the endoleaks at concentrations consistent with those used clinically. A variety of catheters, needles, and sheaths were tested in the study, with both metallic needles and plastic sheaths and catheters demonstrating equal success in achieving embolization. The study showed a slight increased resistance to removal when curved catheters were used or when a catheter was placed through the sheath into the sac. The results of the current study confirm the clinical finding that NBCA can be used to successfully treat type 2 endoleaks using a variety of catheters and needles. While the results of the study are important, it is more important to remember there is still much to be learned regarding the treatment of abdominal aortic aneurysm using endovascular techniques, particularly regarding the treatment of complications such as endoleaks. This study should remind vascular surgeons of the importance of laboratory studies in the development of new clinical techniques and confirming the efficacy of existing clinical techniques. Vascular surgeons should be encouraged to aggressively strive to correlate clinical and laboratory findings.