Three-dimensional rotational angiography of the inferior vena cava as an adjunct to inferior vena cava filter retrieval.

The objective of this study was to explore the role of three-dimensional (3-D) rotational angiography (RA) of the inferior vena cava (IVC; 3-D CV) before filter retrieval and its impact on treatment planning compared with standard anteroposterior cavography (sCV). Thirty patients underwent sCV and 3-D CV before IVC filter retrieval. Parameters assessed were: projection of filter arms or legs beyond the caval lumen, thrombus burden within the filter and IVC, and orientation of the filter within IVC. Skin and effective radiation doses were calculated. Statistical analysis was performed using paired Student t test and nonparametric McNemar's test. Standard anteroposterior cavography detected 49 filter arms or legs projecting beyond the caval lumen in 25 patients. Three-dimensional CV demonstrated 89 filter arms or legs projecting beyond the caval lumen in 28 patients. Twenty-two patients had additional filter arms or legs projecting beyond the caval lumen detected on 3-D CV that were not detected on sCV (p < 0.001). Filter apex tilt detection differed significantly (p < 0.001) between sCV and 3-D CV, with 3-D CV being more accurate. The filter apex abutted the IVC wall in 10 patients (33%) on 3-D CV, but this was diagnosed in only 3 patients (10%) with sCV. Thrombus was detected in 8 patients (27%), 1 thrombus of which was seen only on 3-D CV, and treatment was changed in this patient because of thrombus size. Mean effective radiation doses for 3-D CV were approximately two times higher than for sCV (1.68 vs. 0.86 mSv), whereas skin doses were three times lower (12.87 vs. 35.86 mGy). Compared with sCV, performing 3-D CV before optional IVC filter retrieval has the potential to improve assessment of filter arms or legs projecting beyond the caval lumen, filter orientation, and thrombus burden.

Subintimal arterial flossing with antegrade-retrograde intervention (SAFARI) for subintimal recanalization to treat chronic critical limb ischemia.

PURPOSE: To describe the technique of subintimal arterial flossing with antegrade-retrograde intervention (SAFARI) to improve technical success for the performance of subintimal recanalization when there is failure to reenter the distal true lumen or when there is a limited segment of patent distal target artery available for reentry. MATERIALS AND METHODS: Subintimal recanalization was attempted in an antegrade direction in all patients. If reentry into the distal true lumen was unsuccessful or a short segment of target artery was present, retrograde access was obtained in the distal target artery (popliteal, anterior tibial/dorsalis pedis, or posterior tibial) and a retrograde subintimal channel was created. A guide wire was used to connect the retrograde and antegrade subintimal channels simultaneously to create a "flossing" guide wire. The subintimal tract was dilated with balloon angioplasty with or without stent implantation. Limb salvage, amputation-free survival, and survival rates over time were determined. RESULTS: The SAFARI technique resulted in successful subintimal recanalization creating straight-line flow to the foot in all 21 limbs in 20 patients in which the technique was attempted. Antegrade-retrograde access was performed with the femoral artery and the following vessels: popliteal, n = 11; anterior tibial/dorsalis pedis, n = 10; and posterior tibial, n = 2 (two limbs involved multiple accesses). All procedures were successful. The limb salvage rate with SAFARI was 90% (95% CI, 74%-100%) at 6 months. CONCLUSIONS: The SAFARI technique can be useful for completing subintimal recanalization when there is failure to reenter the distal true lumen from an antegrade approach or when there is limited distal target artery available for reentry. The SAFARI technique improves technical success in the performance of subintimal recanalization. Limb salvage rates are comparable to those with antegrade subintimal recanalization.

Percutaneous intentional extraluminal recanalization in patients with chronic critical limb ischemia.

PURPOSE: To review percutaneous intentional extraluminal recanalization (PIER) for treatment of patients who are poor candidates for infrainguinal arterial bypass surgery (IABS) and have arterial occlusions and chronic critical limb ischemia (CCLI). MATERIALS AND METHODS: Patients with CCLI who were poor candidates for IABS were candidates for PIER. PIER was performed to create continuous arterial flow to the foot for limb salvage. PIER was attempted in 40 patients (22 men, 18 women; median age, 69 years; age range, 44-87 years). Of these patients, 24 (60%) had diabetes, 17 (42%) had renal disease, and 26 (66%) had coronary artery disease. Wound healing was evaluated at follow-up. Kaplan-Meier curves were constructed to evaluate limb salvage, survival, and amputation-free survival. RESULTS: Fifty procedures were attempted in 44 limbs. Tissue loss was present in 40 (91%) limbs, and rest pain was present in four (9%); technical success occurred in 38 (86%). Thirty-seven (84%) of 44 limbs treated with PIER involved tibial vessels (tibial vessels only, n = 15; tibial and superior femoral artery [SFA] and/or popliteal vessels, n = 22). Sixty-six infrainguinal arterial vessel segments (SFA, n = 29; tibial, n = 37) in 38 limbs (1.7 segments per limb) were successfully treated with PIER. Thirty-five (95%) of 37 tibial occlusions and 24 (83%) of 29 SFA and/or popliteal occlusions were longer than 10 cm. Median run-off scores were 5.3 (range, 3-8) and 6.6 (range, 3-9) for patients with tibial occlusions and SFA and/or popliteal occlusions, respectively, as scored with modified Rutherford weighting of run-off arteries. Median follow-up was 7.8 months (range, 1-24 months). Twelve months after PIER, Kaplan-Meier analysis showed limb salvage rate was 66%, survival rate was 71%, and amputation-free survival rate was 48% in these patients. The 30-day mortality rate was 2.5%. Major complications occurred in four (10%) patients, and minor complications occurred in an additional four (10%). CONCLUSION: PIER is a useful percutaneous technique for limb salvage in patients with CCLI.

Safety and efficacy of ERCP in pregnancy.

BACKGROUND: Choledocholithiasis during pregnancy increases the risk of morbidity and mortality for both fetus and mother because of cholangitis and pancreatitis. ERCP has been advocated as safe and effective in pregnant women, but fetal radiation exposure is not routinely monitored. The aim of this study was to record fetal exposure to ionizing radiation during ERCP and to assess outcome. METHODS: Seventeen ERCPs were performed in pregnant women between January 1995 and August 2003. Techniques to minimize fluoroscopy were used, and fluoroscopy times were recorded. Thermoluminescent dosimeters affixed to the skin of the mother were used to estimate fetal radiation exposure. OBSERVATIONS: Mean gestational age was 18.6 (8.9) weeks (range 5-33 weeks). Mean fluoroscopy time was 14 (13) seconds (range 1-48 seconds). Estimated fetal radiation exposure was 40 (46) mrad (range 1-180 mrad). There was a correlation between fluoroscopy time and radiation exposure, but there was a wide range of radiation exposure for individual fluoroscopy times. Complications included post-sphincterotomy bleeding in one patient (controlled by hemoclip placement) and post-ERCP pancreatitis in one patient that necessitated 3 days of hospitalization. Two women developed third-trimester preeclampsia, and labor was induced in both. Thirteen of the 15 patients who delivered were contacted and they confirmed that their child was in good health. CONCLUSIONS: ERCP with modified techniques is safe during pregnancy. Dosimetry should be routinely recorded.

Gadolinium-based contrast agents in angiography and interventional radiology.

Gadolinium is useful as an alternative contrast agent for diagnostic angiographic and interventional procedures in patients with renal insufficiency or a history of a severe reaction to iodinated contrast material. Gadolinium usually is used as a "problem solver" to answer specific diagnostic questions or guide interventional procedures that cannot adequately be defined with CO2 angiography. Because of dose limitations with Gd, careful planning is required prior to its use with angiography or interventional procedures.

Gadolinium chelates in angiography and interventional radiology: a useful alternative to iodinated contrast media for angiography.

Gadolinium has physical properties that are well suited for radiographic imaging. Digital subtraction angiography with a gadolinium chelate as contrast medium can provide images of suitable quality for diagnosis and intervention. The overall safety profile of gadolinium-based contrast media is excellent. In particular, these contrast media are well tolerated in patients with renal insufficiency when administered intraarterially in doses of less than 0.3-0.4 mmol per kilogram body weight, with a decreased incidence of contrast medium-induced nephropathy, as compared with similar volumes of iodinated contrast material. The currently available formulations of gadolinium chelates can be injected safely into every arterial and venous structure. However, substantial data are lacking on the intraarterial use of gadolinium in patients with renal insufficiency, particularly at doses that exceed those routinely used in magnetic resonance angiography. Gadolinium chelates in appropriate volumes are useful alternative contrast media in selected high-risk patients undergoing angiographic studies.