The Simon nitinol filter: evaluation by MR and ultrasound.

In this prospective blinded study of inferior vena caval (IVC) patency, 18 patients underwent 25 duplex ultrasound (US) and magnetic resonance (MR) angiography examinations over an eight-month period following Simon nitinol filter placement. Clinical examination for lower extremity venous stasis and plain abdominal radiography were also performed. Twenty-three of 24 MR examinations and 11 of 24 US examinations were judged technically adequate by the blinded observers. One technically adequate US exam was false positive for intraluminal caval thrombus. Thirteen technically inadequate US examinations missed 3 complete caval occlusions and 2 partial occlusions. MR identified all patients with complete or partial caval occlusion. The authors conclude that duplex US reliably confirms IVC patency only when strict criteria for technical adequacy and interpretation are met (good visualization of filter and IVC above and below filter). MR, although expensive, more reliably identifies nonoccluding intraluminal thrombus and caval occlusion. It should be the noninvasive study of choice in symptomatic patients with venous stasis and patients with recurrent pulmonary emboli.

Peripheral directional atherectomy: 4-year experience.

Directional atherectomy alone or with supplemental percutaneous transluminal angioplasty was used to treat peripheral vascular lesions in 77 patients (85 procedures). Lesions involved 17 iliac arteries, 45 infrainguinal arteries, and 23 laser extremity vein bypass grafts. Technical success, defined as reduction of stenosis diameter to 30% or less of the normal vessel diameter, was achieved in 78 of 85 (92%) cases. The complication rate was 21% (18 of 85 procedures). Most complications were minor and were related to puncture sites. Patients underwent noninvasive follow-up studies, including measurement of ankle-brachial index and segmental pressures, plethysmography, and clinical examination. The mean follow-up period was 13.5 months. The probability of 1-, 2-, and 3-year patency for lesions treated with atherectomy alone was 92%, 84%, and 84%, respectively. Kaplan-Meier survival analysis revealed no difference in 2- to 3-year patency rate on the basis of lesion location or presence of calcification, eccentricity, or ulceration. Diabetic patients, however, had a higher restenosis rate than did patients who were not diabetic (P less than .03).

Role of superficial femoral artery puncture in the development of pseudoaneurysm and arteriovenous fistula complicating percutaneous transfemoral cardiac catheterization.

Of 13,203 transfemoral diagnostic and therapeutic cardiac catheterization procedures performed between January 1, 1980 and December 31, 1990, 73 (0.55%) were complicated by pseudoaneurysm (PA) formation, and 15 (0.11%) by arteriovenous fistulas (AVF). The rate of PA increased progressively from 0.44% (1980-1987), to 0.59% (1987-1989), to 0.92% (1990), with no corresponding change in the incidence of AVF. The rising incidence of PA complicating transfemoral cardiac catheterization was associated closely with the use of larger diameter catheters and aggressive antiocoagulation during coronary interventions, but findings during surgical repair suggested that puncture of the superficial femoral (SFA), rather than the common femoral artery (CFA), was an important avoidable cause of some PA and AVF. A technique for fluoroscopic localization of the puncture site to avoid inadvertent SFA puncture and the associated increased risk of complication is proposed.

Percutaneous enterostomy with the Cope suture anchor.

Eighty-two percutaneous enterostomies were performed at three institutions with the Cope suture anchor for stomach or jejunal wall stabilization during alimentation tube placement. The anchors were successfully placed into the stomach or jejunum in 81 cases. Early in the series, two anchors were misplaced, with no sequelae. There were no other complications at the time of placement. In all successful cases, excellent immobilization of the viscus was achieved. Tract dilation and tube placement were easily performed, and there were no guidewire or tube dislodgments.

Double-lumen needle for percutaneous ureteral pressure-flow studies.

Ureteral perfusion studies in patients without preexisting renal access currently must be intermittently interrupted for intrarenal pressure measurement. A double-lumen needle has been successfully placed in four patients (two with native and two with transplanted kidneys). This permits simultaneous perfusion and intrarenal pressure monitoring yet maintains the safety and ease of use of a single skinny needle.