1Clinique Saint-Gatien Radiologie Vasculaire Diagnostique & Interventionnelle Tours 2Clinique Jouvenet Surgery Paris France Email: luc.turmel{at}wanadoo.fr
Sir,
We were happy to read that Tordoir et al. [1] concluded that "an aggressive approach towards early interventional treatment of these non-functional AVFs (arteriovenous fistulas for dialysis) is worthwhile and leads to a considerable salvage rate". However, there are three major points of disagreement between the Dutch team and our experience concerning diagnostic, therapeutic and strategic approaches.
From a diagnostic point of view, the authors claim that angiography did not reveal any abnormality in 36% of their cases of non-maturation, which opposes a previous publication in which we reported that a stenosis or chronic occlusion was found in all cases [2]. There are three possible explanations for this apparent discrepancy.
First, the authors never mention the only differential diagnosis of immaturity, which is the deep location of the vein, a diagnosis made by ultrasound and which is treatable by surgical transposition of the vein into a more superficial location.
Secondly, whereas we emphasized that angiography by arterial puncture at the elbow is mandatory for correct evaluation of these immature fistulas, angiography in the Dutch article was performed by puncture of the vein and retrograde arterial filling obtained after placement of a venous cuff on the limb. Such unphysiological opacification, leading to numerous superimpositions, may by itself explain the misdiagnosis of stenoses.
Thirdly, the Dutch surgeons and radiologists interpret small insufficiently developed arteries and veins as poor vessels, whereas we consider that arteries and veins do not increase in diameter after fistula creation because they are stenosed.
From a therapeutic point of view, the authors report that only "short segmental stenosis (<1 cm) in the cephalic vein underwent balloon angioplasty" and that fistulas "without demonstrable stenoses, usually indicating poor vessel remodelling, were abandoned", which indicates a restricted view of the place of interventional radiology. All stenoses, short or long, arterial or venous, are amenable to angioplasty, especially in immature fistulas since this is the only chance to save the fistula and to preserve the patients venous capital. We therefore oppose the authors view when they write that "remodelling failure of the radial artery is not cured by revision" since most of the time it is cured by endovascular revision.
From a strategic point of view, we are surprised to read that a European team gives greater importance to prosthetic graft placement than autogenous fistula creation at the elbow when a forearm fistula fails or is deemed not feasible. Such an attitude opposes all the findings of the international literature. In Europe, Rodriguez published mean secondary patency rates ranging from 3.6 to 5.1 years for autogenous elbow fistulas compared to only 1 year for grafts [3]. The American DOQI guidelines emphasize that prosthetic grafts should be placed only when brachiocephalic fistulas cannot be created [4]. In addition, forearm graft placement invariably results in a stenosis of the venous anastomosis, with either the basilic vein or the cephalic vein at the elbow, and this means that these veins which are damaged by a more or less extensive stenosis might be then unusable for autogenous fistula creation. The authors are therefore not convincing and shoot themselves in the feet when they write that "therefore it seems vital to obtain autogenous fistulas in all new dialysis patients".
Conflict of interest statement. None declared.
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