Stent-Apposition Salvage of an Anterior Tibial Artery After Inadvertent Angioplasty Balloon Retention During CTO Revascularization.

INTRODUCTION: Progressive improvement in the ability to treat complete total occlusions in the tibial level arterial circulation have made it possible to revascularize patients with critical limb ischemia. REPORT: A 59 year old male presented with a complete total occlusion of his anterior tibial artery with distal reconstitution through peroneal artery collaterals. During attempted angioplasty a balloon was retained within the patent portion of the target vessel. Two 3.0 mm drug eluting coronary stents were deployed across the length of the balloon with excellent luminal preservation. DISCUSSION: Successful CTO revascularization was completed and a strong dorsalis pedis artery pulse was restored following intervention.

Long-term intermittent compression increases arteriographic collaterals in a rabbit model of femoral artery occlusion.

OBJECTIVES: To assess the effects of intermittent limb compression on arterial collateral formation in a rabbit-model. DESIGN: Animal study. MATERIAL AND METHODS: New Zealand rabbits (n=11), aged 2-years, weight of at least 4.0 kg, underwent bilateral superficial femoral artery ligation. In ten of these, the experimental leg underwent 60 minutes of daily intermittent compression for a ten week period with 3 sec/90 mmHg pressure inflation and a cycle of 3 times per minute. The contra-lateral limbs were not treated. At the end of the ten-week period, high-resolution angiograms were obtained by barium infusion into the aorta. The angiograms were analyzed in a blinded manner and the number of collateral arteries larger than 100 microns, was counted. Following perfusion-fixation, histological specimens of transverse sections of the compressed semi-membranous muscle were examined. RESULTS: The compressed limbs demonstrated a significantly (8.1+/-.87 vs 6.0+/-.97; p<0.005) greater number of collateral vessels, ranging in size from 100-700 microns, as compared to the control sides. The mean size of collaterals in the compressed limbs was not significantly different (0.33+/-0.17 vs 0.31+/-0.16). Microscopic examination of the collaterals confirmed remodeling by a typical neo-intima consisting of 6-7 cell-layers. CONCLUSIONS: Intermittent limb compression increases the number of angiographical collateral arteries.

Analysis of the CD40/CD40L role in the sustenance of alloreactive antibody production.

CD40 ligand (CD40L) is important for T/B lymphocyte interaction. To understand the cellular basis of humoral allosensitization we, therefore: (1) measured CD40L protein and gene expression in sensitized and non-sensitized uremic unactivated peripheral CD4+ T lymphocytes; (2) studied the impact of blocking the CD40/CD40L pathway on alloreactive antibody (allo-Ab) production by engrafted sensitized PBLs into severe combined immunodeficient (SCID) mice after in vitro preactivation with IL2/LPs/HLA class II allopeptides and adjuvants as a potent stimulus to produce allo-Ab (Shoker et al. Transplantation 1999;68;1188); and (3) studied the modifying effect of CD40/CD40L blockade on T helper type I and II cytokine gene expression in the respective mice spleen. The CD40L protein was measured by flow cytometry and the gene expression was measured by quantitative RT-PCR. Alloreactive antibodies (alo-Abs) produced by sensitized PBLs engrafted into SCID mice with and without blockade of the CD40 receptor were measured by the PRA-STAT ELISA method. The modifying effects of CD40 blocking on allo-Ab production and cytokine gene expression by the engrafted cells measured by RT-PCR were then compared. There was no detectable CD40L protein expression in either the uremic or the control groups. The CD40L gene expression of 0.04 +/- 0.02 attomoles (aM) in the sensitized group was significantly higher than in the non-sensitized patients (0.009 +/- 0.007 aM, P < 0.0001) or the control CD4+ T cells (0.016 +/- 0.004 aM, P < 0.001). Blockade of the CD40 receptor abrogated the production of allo-Ab antibodies by the engrafted sensitized cells in 60% of the tested mice (n = 10); decreased the mean +/- S.D. optic density of allo-Ab to 0.1 +/- 0.13 and the mean +/- S.D. PRA to 12 + 16). In the presence of the control Ab, allo-Ab production in SCID sera was present in 100% of the 10 SCID mice tested; the mean +/- S.D. PRA was 75 +/- 20, and the mean + S.D. OD activity was 0.412 +/- 0.17. All cytokine genes were, otherwise, expressed in the presence or absence of CD40 blockade. The results suggest a potential role of an enhanced CD40/CD40L interaction in the sustenance of alloreactive antibody production without significant deviation to T helper-like I or II responses. Blocking the CD40/CD40L pathway may have a potential therapeutic benefit to treat sensitized uremic patients.

Thigh isosulfan blue injection in the treatment of postoperative lymphatic complications.

Postoperative lymphatic complications after infrainguinal revascularization are troublesome and potentially serious complications. Vital dye injection into the web spaces of the foot has been recommended as a simple and reliable method to identify lymphatic channel disruption before groin exploration. Such distal injections, however, are not always successful. We describe a modified technique using a proximal thigh injection with isosulfan blue, which is faster and more useful than the distal web space method.