Guide wire perforation leading to fatal perirenal hemorrhage from transcortical collaterals after renal artery stent placement.

After successful renal artery angioplasty and stent placement, a patient in a fully anticoagulated state developed hypotension and flank pain. Review of the intraprocedural angiogram demonstrated transcortical position of the guide wire. Computed tomography of the abdomen revealed a large perinephric hematoma. Although only a single renal artery branch was accessed with the guide wire during stent placement, subsequent emergent angiography revealed extravasation from multiple capsular branches. Renal artery embolization failed to control the hemorrhage. The patient's course rapidly deteriorated and he ultimately died. The unique angiographic finding and proposed mechanism of this fatal complication are described and discussed.

Time-resolved magnetic resonance angiography as a noninvasive method to characterize endoleaks: initial results compared with conventional angiography.

PURPOSE: Several types of endoleaks have been described, each with different methods of treatment. Conventional arteriography is widely regarded as the gold standard for the classification of endoleaks. Recently, faster magnetic resonance gradients have allowed for rapid data acquisition and review of vascular studies as a real-time continuous angiogram (time resolved magnetic resonance angiography [TR-MRA]). This study was performed to compare the findings of TR-MRA with conventional angiography for the characterization of endoleaks. METHODS: Between June 2002 and June 2003, 12 patients with documented endoleaks following endovascular repair of aortic aneurysms (10 abdominal and two thoracic) underwent TR-MRA to identify and characterize the endoleak. All patients had nitinol-based aortic stent grafts. MRA was performed on a 1.5-Tesla magnet (Sonata class; Siemens Medical Systems, Iselin, NJ). The TR-MRA studies were reviewed under continuous observation as a "cine MR angiogram." These MRA data sets were used to classify the endoleaks into types 1 through 3. The patients underwent conventional angiography following the MRA to confirm the findings and to plan treatment. The MRA findings were compared with the findings made at conventional arteriography. RESULTS: TR-MRA identified seven patients with type 1 leaks, including four proximal and three distal. Four patients had type 2 leaks, including two arising from the inferior mesenteric artery and two from an iliolumbar artery. One patient had a type 3 leak. Conventional angiography confirmed the type of endoleak in all 12 patients. CONCLUSION: These initial results demonstrate TR-MRA to be an effective noninvasive method for classifying endoleaks. This technique may allow for screening of patients with endoleaks to identify those requiring urgent repair.

Devices and techniques for endovascular surgery: catheters, stents, coated stents, and stented grafts.

Endovascular/minimally invasive surgery has undergone rapid innovation and growth. From crude, stiff, large-bore tubes that were used initially to evaluate vascular structures, some of the new catheters and wires are only a little bigger than the human hair, which permits their passage in vessels previously thought inaccessible. Closed arteries and veins now can be effectively traversed and blood flow restored by the use of balloons and metallic stents to maintain the integrity of the vascular lumen.