Stent-graft arteriovenous fistula: an endovascular technique in hemodialysis access.

PURPOSE: To determine the feasibility and safety of a new endovascular technique for creating an arteriovenous (AV) fistula utilizing catheter-directed techniques and stents. METHODS: Stent-graft AV fistulas were offered on an experimental basis to 8 patients who had a history of multiple failed access procedures or very small arm veins unsuitable for standard vascular access techniques. The device consisted of a balloon-expandable Palmaz stent attached to the designated venous end of a polytetrafluoroethylene graft. The balloon-mounted stent-graft was inserted into the brachial vein through an arteriotomy and advanced over a guidewire into the axillary vein. After the stent-graft was deployed, the arterial anastomosis was completed in standard surgical fashion using an end-to-side anastomosis of the graft to the brachial artery. RESULTS: The stent-graft was inserted successfully in all patients, but there were two early failures. The first resulted from a steal phenomenon secondary to high flows through the stent-graft, necessitating ligation of the fistula. Another stent-graft was placed too peripherally in the upper arm, and the stainless steel stent was crushed by external compression. Three of the 6 remaining grafts were patent for over 1 year, and 2 grafts are still functioning at 22 and 13 months. CONCLUSIONS: Endoluminal stent-grafts can be successfully inserted into the axillary vein for creation of an AV fistula and remain patent for 2 years or more. This method may be most useful in patients with very small, unusable arm veins or multiple failed AV grafts.

A giant renal artery aneurysm diagnosed post partum.

We report a case of a 5.8 cm. right renal artery aneurysm diagnosed intact 8 weeks post partum. Rupture of a renal arterial aneurysm during pregnancy is a rare but well described catastrophic event. There are no previous reports of an intact renal artery aneurysm diagnosed either ante partum or post partum. To our knowledge, this also represents the largest reported renal artery aneurysm. The aneurysm was repaired successfully with kidney salvage and closure of the fistulous connection to the renal vein.

Analysis of inferior venacavography before Greenfield filter placement.

The value of routine preoperative inferior venacavography through a femoral approach was assessed in 64 patients who required a Greenfield inferior vena cava filter. Nearly 11% of the patients had an abnormality, for example, duplication of the inferior vena cava, circumaortic renal vein, interrupted or discontinuous inferior vena cava, and so on, requiring an alternate approach to placement. No deaths or complications occurred upon recognition of the anatomic variant before filter placement. In three of the seven abnormalities encountered, adequate visualization and filter placement could only have been accomplished through femoral catheterization. Preoperative cavograms before Greenfield filter placement should be routinely performed using a femoral approach in the absence of contraindications to this technique.

Primary aldosteronism: computerized tomography in preoperative evaluation.

We reviewed the value of computerized tomography (CT) in the preoperative evaluation of 34 patients with primary aldosteronism. All 34 patients entered a standard protocol including saline suppression testing, abdominal CT scanning, and adrenal venous sampling. Surgical pathologic findings, biochemical determinations, and clinical response to adrenalectomy were the criteria used to evaluate 68 adrenals in 34 patients. Of 36 diseased glands 17 were correctly identified by CT (48%). Of the 32 normal glands, 29 were identified correctly by CT (91%). Thus, CT is not sensitive (0.48), but very specific (0.91) in Conn's syndrome. Our patients were divided into two groups: group 1 were those scanned between 1977 and 1980, group 2 were those scanned from 1981 to 1983 with a high-resolution GE-8800 scanner. CT results in group 2 showed no significant improvement in specificity (0.92), but improvement in sensitivity (0.58) over group 1 (specificity 0.90, sensitivity 0.42). Furthermore, CT is less sensitive in patients with smaller tumors than in those with larger tumors.