[Recanalization of the lower leg: PTA or stent?]. / Rekanalisation am Unterschenkel: PTA oder Stent?

Percutaneous transluminal angioplasty (PTA) and stent placement are currently accepted methods for endovascular treatment of critical limb ischemia, if infragenual vessels are involved. Outcome results in high technical success and satisfactory clinical results for treatment of infrapopliteal lesions with regard to patency rates and amputation-free survival. These treatment modalities are also safe for the patients. The question whether PAT alone or additional stent placement is the better choice, is still unanswered due to limited data.

CAS: which stent for which lesion.

Current carotid stent designs and their attributes like scaffolding to reduce plaque prolapses and embolization, flexibility, adaptability and conformability to the vessel vary largely. Knowing that differences in behaviour due to stent design exist, especially due to the open cell design (which show high flexibility and therefore adaptability to the vessel but allows in theory easy particle penetration due to open structure) and closed cell designs (which show low flexibility and therefore low adaptability to the vessel but show high resistance to particle penetration due to closed cell design and high scaffolding), physicians have to be aware of these differences when planning carotid artery stenting procedures. The individual characteristics of each stent device may make it an attractive choice in one circumstance but render it less desirable in other situations; in approximately 75% of all procedures, all types of stents will achieve similar outcomes, making adequate device selection unnecessary; for the remaining quarter, careful preoperative screening is mandatory. The aim of this article was to review different stents with regard to latest designs intended for carotid stenting with regard to topics as mentioned above highlighting latest developments in specific designs especially developed for carotid lesion treatment.

[Transjugular intrahepatic portosystemic shunt: evaluation of the impact of the stent's configuration on the patency rate]. / Transjugulärer intrahepatischer portosystemischer Shunt: Untersuchung des Einflusses der Stentkonfiguration auf die Offenheitsrate.

PURPOSE: To evaluate the impact of the configuration of the stent on the patency rate after transjugular intrahepatic portosystemic shunt with a self-expanding stent. MATERIALS AND METHODS: In total, 80 patients (60 male, 20 female; mean age 56 +/- 9.6, range 37 - 81) with a transjugular intrahepatic portosystemic shunt were evaluated. The primary technical success rate, interventional revision rate, and mean patency rate according to Kaplan-Meier were calculated. The angle of deviation of the blood flow at the portal venous inflow and central venous outflow were measured on projected angiograms (valid cases, n = 78). The following five angle groups were established: 1. portal venous inflow, 2. central venous outflow, 3. maximum, angle, 4. minimum angle, and 5. sum of both angles in the shunt system. Within each group, the Mann-Whitney Test and after dichotomic partition using the median Pearson's Chi-Square Test and Fisher's Exact Test were carried out to prove the dependency of the patency on the stent's configuration. RESULTS: The primary technical success rate was 93 %, the interventional revision rate was 28 %, and the mean patency rate was 17.5 months. The mean/standard deviation/median angle were as follows: 1. portal venous inflow 66.5 degrees / 19.2 degrees / 65 degrees , 2. central venous outflow 43.7 degrees / 14.0 degrees / 40 degrees , 3. maximum angle 69.1 degrees / 16.3 degrees / 65 degrees , 4. minimum angle 40.6 degrees / 13.3 degrees / 40 degrees , and 5. sum of both angles 110.2 degrees / 21.8 degrees / 110 degrees . The 2-sided values of significance in the Mann-Whitney Test/Chi-Square Test/Exact-Fisher Test were as follows: 1. portal venous inflow 0.112 / 0.066 / 0.083, 2. central venous outflow 0.960 / 0.919 / 1.000, 3. maximum angle 0.151 / 0.042 / 0.056, 4. minimum angle 0.578 / 0.622 / 0.632, and 5. sum of both angles 0.104 / 0.111 / 0.140. CONCLUSION: The shunt's patency rate when using a self-expanding stent is not dependent on the stent's configuration regarding the deviation of the blood flow at the portal venous inflow and central venous outflow, and the maximum, minimum and total deviation in the shunt.

Variation of a Persistent Primitive Hypoglossal Artery (PPHA) as Incidental Finding in the Diagnostic Clarification of Cerebral Vasculopathy Associated with Intracranial Vasculitis.

We present a very rare variation of a persistent primitive hypoglossal artery (PPHA) arising from the internal carotid artery, detected during a diagnostic angiography. A 50-year-old female patient was admitted with an atypical intracranial hematoma in the left frontal lobe. Catheter angiography revealed intracranial vasculopathy with segmental stenoses, a small aneurysm of the right internal carotid artery bifurcation and a "string of beads" appearance of the left carotid artery, consistent with fibromuscular disease. On the left side, a vertebral artery ending in the posterior inferior cerebellar artery (PICA) was detected, whereas on the right side the vertebral artery was aplastic. During selective angiography of the right common carotid artery, a persistent hypoglossal artery was seen supplying the basilar artery. The literature of persistent embryonal carotid-vertebrobasilar anastomosis and their anatomical variations is discussed with respect to clinical importance for ischemia, interventional procedures, and surgery.

[Does interventional therapy prolong the patency of hemodialysis fistulas and grafts?]. / Verlängert die radiologisch-interventionelle Therapie die Shuntnutzungsdauer bei hämodialysepflichtigen Patienten?

PURPOSE: To retrospectively evaluate procedural success and patency after endovascular treatment of acute dysfunctional hemodialysis fistulas and grafts in a non-preselected patient cohort. MATERIALS AND METHODS: 185 angiographies of hemodialysis fistulas and grafts on the upper extremities were analyzed for 120 patients (53 male, 67 female; mean-age 63.1 +/- 11.4, range 24 - 91). 70 % (n = 130) were native arteriovenous fistulas, 17 % (n = 31) were prosthetic grafts, and 13 % (n = 24) were non-specific. In total, 278 lesions requiring endovascular treatment were detected. 13 % (n = 35) of the lesions were located in the arterial inflow, 18 % (n = 49) in native arteriovenous anastomoses, 7 % (n = 19) in prosthetic grafts and 62 % (n = 171) in the venous outflow. The primary, secondary and cumulative patency after endovascular treatment was calculated. RESULTS: In 51 % (n = 94) of the cases endovascular treatment could be performed, in 8 % (n = 14) no lesion requiring treatment was detected, and in 42 % (n = 77) intervention was not considered possible. In 45 % (n = 124) of the detected lesions endovascular treatment was successful, in 18 % (n = 51) the intervention failed, and in 37 % (n = 103) intervention was not considered possible. The complication rate was 5 % (n = 10). The primary, secondary, and cumulative patency rates for 50 % of the hemodialysis fistulas and grafts after endovascular treatment were 65, 191, and 370 days, respectively. The results differed significantly from each other with p < 0.05 in the log rank test and log rank trend test. CONCLUSION: Endovascular treatment of acute dysfunctional hemodialysis fistulas and grafts is effective in restoring the patency for hemodialysis.

Impact and Effectiveness of Dual Aspiration Technique in Stent-Assisted Mechanical Thrombectomy: Recent Improvements in Acute Stroke Management.

BACKGROUND AND PURPOSE: To evaluate feasibility and impact of dual aspiration technique (DAT) within stent-assisted mechanical thrombectomy on procedural parameters and clinical outcome. MATERIALS AND METHODS: Within 16 months, 76 consecutive patients (mean age 70.7 year; range 33-89) underwent stent-assisted mechanical thrombectomy. Of 52 enrolled patients (68.4 %) with occlusion of the anterior circulation, 22 patients (42.3 %) underwent DAT; 30 patients (57.7 %) were treated in conventional monoaspiration technique (MAT). Epidemiological data, clinical and imaging characteristics (mRS, NIHSS, ASPECTS) as well as procedural details were analyzed (TICI, number of retrieval, procedure time). Clinical outcome was determined with mRS at discharge and after 90 days. RESULTS: In the context of DAT additional carotid artery stenting was required in 45.5 % (10/22) in underlying tandem lesion (vs. 0/30 MAT). No differences were found in NIHSS at admission (MAT: 20.5, range 15-29; DAT: 18.6; range 11-25), mRS at admission (MAT: 4.6 vs. DAT: 4.57) or ASPECT score (MAT: 8.3, ±1.5; DAT: 8.4, ±1.5; P > 0.05). TICI ≥ 2b/3 was conducted in 90 % (MAT) and 100 % (DAT), respectively. The procedure time was longer in the MAT group (65 min, ±25.9, range 18-126) compared to the DAT group (49.7 min, ±15, range 32-101; P = 0.016). The clinical outcome increased from admission to discharge and in follow-up after 90 days (mRS ≥ 2: MAT: 53.3 %, DAT: 54.5 %; P > 0.05). CONCLUSIONS: The dual aspiration technique with an additional intermediate guide catheter placed closed to the stent retriever leads to decreased procedure time in the anterior circulation. Even in cases with higher thrombus load and treated in DAT, clinical outcome improved.

Comparison of the mechanical thrombectomy efficacy of the Amplatz thrombectomy device and the Cragg thrombolytic brush in vitro.

RATIONALE AND OBJECTIVES: To determine the efficacy of thrombectomy (without thrombolytic agents) for the Amplatz thrombectomy device (ATD) and the Cragg thrombolytic brush catheter (CBC) in vitro. METHODS: Thrombectomy was performed with the ATD or CBC (6F) in a flow model. Embolus sizes, weight, remaining thrombus, and activation time were evaluated. RESULTS: No significant difference in the activation time was found. The CBC produced significantly less embolism (3.3% vs. 0.03% in the 5-mm and 89% vs. 0.5% in the 7-mm model), but also much more thrombus remained in the system than with the ATD (1% vs. 41% in the 5-mm and 0.1% vs. 62% in the 7-mm model). CONCLUSIONS: The ATD can remove almost all thrombus (99%), whereas the CBC removes only up to 60%, producing fewer emboli than the ATD. This might be due to the lower rotational speed of the CBC compared with the ATD, which is 20 times greater. The soft nylon brush offers less resistance and shear force toward the thrombus than the stainless-steel impeller of the ATD. Because of the large amount of remaining thrombus, the CBC should not be used without lytic agents.

Enhancement of in vitro effectiveness for hydrodynamic thrombectomy devices. Simultaneous high-pressure rt-PA application.

RATIONALE AND OBJECTIVES: To determine the efficacy of simultaneous high-pressure recombinant tissue plasminogen activator (rt-PA) application for clot removal and procedure-related peripheral particle embolization for the hydrodynamic thrombectomy devices LF 140 AngioJet (LF 140) and triplelumen Hydrolyser (triple HL) in an in vitro flow model. METHODS: Thrombectomy of clots (n = 47) from 5-day-old human blood (8.9-9.7 g) was performed with the LF 140 and the triple HL, each with and without simultaneous rt-PA (9.97-12.59 g) application in a flow model (flow 1 liter/min) made of silicone tubes (7 mm inner tube diameter). All catheters were used according to the manufacturer's recommendations. RESULTS: The triple HL revealed no statistically significant performance differences with additional rt-PA. For the LF 140, mean thrombectomy time ranged from 23.5 sec (with rt-PA) to 33.5 sec (P = 0.05). The ratio of peripheral embolus weight to thrombus weight was reduced from 2.12% to 0.46% (rt-PA; P = 0.05). None of the tested devices had an isovolumetric performance; the mean ratio of applied saline to aspirated fluid for the devices were different from one, ranging from 0.89 to 0.92 (rt-PA) for the triple HL and from 0.43 to 0.52 (rt-PA) for the LF 140. No significant differences for remaining thrombus within the tubes were found. CONCLUSIONS: Simultaneous rt-PA-enhanced hydrodynamic thrombectomy is feasible in vitro. This combination reduces the time for thrombectomy and procedure-related peripheral particle embolization for the LF 140. No effect could be demonstrated for the triple HL in an in vitro flow model. It remains unclear whether this procedure is effective in vivo. It seems likely that the incidence of fibrinolysis-associated complications may increase in vivo.

Mechanical assistance for enhancement of in vitro effectiveness for hydrodynamic thrombectomy.

OBJECTIVE: To determine whether the efficacy for clot removal and procedure-related peripheral particle embolization for the hydrodynamic thrombectomy device CF 105 AngioJet (CF 105) can be enhanced with the use of guiding catheters and an occlusion balloon in an in-vitro flow model. METHODS: Thrombectomy of clots (n = 97) from 5-day-old human blood (range, 9.28-9.77 g) was performed with the CF 105 alone, with additional guide wires (CF 1050.014/0.018), with a 30 degree angled tip (CF 10530 degrees), with guiding catheters (CF 105MP/HS), and with an additional occlusion balloon (CF 105OB) in a flow model (flow 1 L/min) of silicone tubes (inner tube diameter, 7 mm). RESULTS: Mean thrombectomy time ranged from 28.71 seconds (CF 105OB) to 37.02 seconds (CF 10530 degrees). When a guide wire was used, the time for thrombectomy was not prolonged. None of the devices tested worked isovolumetrically. The ratio of applied saline and aspirated fluid (0.34) for CF 105 alone was significantly better than for CF 1050.014/0.018 (0.49/0.60; for both P < 0.001). Compared with CF 105 alone (273.16 mg), wall-adhesive thrombus was reduced significantly with CF 105MP (43.66 mg), CF 105HS (48.66 mg), and CF 10530 degrees (97.27 mg; P < 0.001 for all). Compared with the highest rate of embolism for CF 105 alone (4.62%), CF 105OB (2.50%; P < 0.001), CF 105HS (3.04%; P < 0.001), CF 105MP (3.49%; P < 0.001), and CF 105018 (3.64%; P < 0.001) produced better ratios. CONCLUSIONS: The use of guiding catheters and occlusion balloons is feasible to enhance hydrodynamic thrombectomy in vitro. This combination reduces procedure-related peripheral particle embolization and wall-adhesive thrombus during hydrodynamic thrombectomy. To avoid blood loss, the device should be used only with a 0.018" guide wire.

Rheolytic hydrodynamic thrombectomy for percutaneous treatment of acutely occluded infra-aortic native arteries and bypass grafts: midterm follow-up results.

RATIONALE AND OBJECTIVES: To evaluate the efficacy of a rheolytic thrombectomy catheter (RTC) for treatment of acutely occluded infra-aortic native arteries and bypass grafts and to determine midterm primary patency, death, and amputation-free survival rates. METHODS: From March 1995 to September 1997, 112 patients with occluded arteries or bypass grafts were primarily treated with RTC at two centers. Thrombus removal was evaluated by two angiographers. RESULTS: More than 75% of the thromboembolic material could be removed with RTC alone. Mean activation time of RTC was 280 +/- 163 seconds. Residual mural or organized thrombi (29%) required adjunctive fibrinolytic therapy or aspiration thrombectomy. Remaining stenoses were treated with percutaneous transluminal angioplasty and additional stent implantation. For acute reocclusions, surgical intervention was required. Technical success after the entire procedure was 88.4%. RTC-associated complications included distal embolization, dissection, vessel perforation, and technical failure of RTC. Mean follow-up time was 14.8 months +/- 11.5, rates of primary patency, secondary patency, death, and amputation-free survival were 60%, 84%, 16%, and 75% after 2 years, respectively. CONCLUSIONS: RTC is a rapid and efficient technique for mechanical thrombectomy of acutely thrombosed native leg arteries and bypass grafts. Midterm results are comparable to the results of alternative treatment modalities such as Fogarty balloon thromboembolectomy or local fibrinolysis.

Visualization of flow patterns from stents and stent-grafts in an in vitro flow-model.

RATIONALE AND OBJECTIVES: The authors determine flow characteristics and pressure gradients of different stents and stent grafts in an in vitro flow-model. METHODS: Five vascular stents (Memotherm, Cragg, two Palmaz P308, Strecker, and Wall) and one stent graft (Cragg EndoPro System 1), equal in length (60 mm) and diameter (10 mm), were deployed in a closed flow-model. The inner diameter of the tube measured 9 mm. Flow at 1.5 L/min, 6 L/min, and 10 L/min was simulated. Flow patterns were visualized by anionic particles illuminated with two Helium-Neon lasers. Laminary flow characteristics and pre-/poststent pressure gradients were determined in either expanded stent, 25% stenosis, or 50% stenosis. RESULTS: Stent implantation induced a decrease of laminary flow compared with an unstented tube with and without concentric 25% stenosis (P < 0.01) at all flow rates and an increase of pressure gradients compared with an unstented tube for flow rates greater than 1.5 L/min (P < 0.01) (except for Cragg EndoPro System 1 stent, which revealed an increase of the pressure gradient at a flow rate of 1.5 L/min [P < 0.01]). Memotherm stent permitted maximum of laminary flow at all flow rates and stenoses (expanded: 79.50% at 1.5 L/min to 69.90% at 10 L/min; P < 0.01). Memotherm and Palmaz permitted lowest pressure gradients (P < 0.01). All of the endoprostheses demonstrated laminary flow at 50% stenosis. CONCLUSIONS: The investigated stents and stent grafts showed different severity of flow disturbances and pressure gradients at different graded stenoses. Inadequate stent depolyment bears the risk of creating less laminary flow and pathologic pressure gradients. Because flow disturbances and pressure gradients may influence neointimal hyperplasia, stent design and completeness of stent unfolding are important regarding the appearance of postinterventional restenoses.

Mechanical thrombectomy of major and massive pulmonary embolism with use of the Amplatz thrombectomy device.

RATIONALE AND OBJECTIVES: To evaluate the feasibility of mechanical thrombectomy with the Amplatz thrombectomy device (ATD) in restoring patency of acutely thrombosed pulmonary arteries resulting from pulmonary embolism for the improvement of patient outcome. METHODS: Mechanical thrombectomy with the ATD (8F) was performed in nine consecutive patients with angiographically documented thrombus in the left or right pulmonary artery resulting from deep vein thrombosis (n = 4) or unknown cause (n = 5). RESULTS: The Miller index decreased from 18 to 11. In all patients, the majority of the thrombus in the pulmonary artery was cleared after a mean activation time of the ATD of 367 seconds. Thrombectomy was performed with the ATD alone (n = 4) or with additional long-term fibrinolysis therapy (n = 5) with infusion of recombinant tissue-type plasminogen activator. Pulmonary arterial pressure decreased from a mean of 57 mm Hg before mechanical thrombectomy to 55 mm Hg directly after the procedure and to 39 mm Hg after termination of the recombinant tissue-type plasminogen activator infusion. CONCLUSIONS: Mechanical thrombectomy with the ATD in patients with minor and major pulmonary embolism is technically feasible and safe. It is a potential alternative to drug-mediated thrombolysis and surgery. However, the incremental benefit of the ATD over conventional treatments could be shown only in a randomized controlled study.

Characterization of ultrasmall magnetite [correction of paramagnetic magnetite] particles as superparamagnetic contrast agents in MRI.

RATIONALE AND OBJECTIVES: Very small dextran-coated magnetite particles were developed. These particles can be used either as immunospecific contrast agents for MRI by coupling to antibodies or as an interstitial contrast agent. METHODS: The particles were synthesized from iron chloride/dextran solutions. Size was evaluated by electron microscopy and photon correlation spectroscopy. The iron concentration was determined by x-ray spectroscopy. T1 and T2 values as well as relaxivities RI and R2 were evaluated with a clinical MR scanner at 1.5 T. Biocompatibility assays were performed with the cell line U937 in methylcellulose cultures. RESULTS: Superparamagnetic, dextran-coated magnetite particles with a hydrodynamic diameter of 10 nm were developed. The iron core size was 7 nm; R1,7 L/mmol x s; and R2, 19 L/mmol x s. These particles are smaller than those currently available commercially and therefore show a smaller R1 to R2 ratio. Biocompatibility tests have shown no toxic side effects so far. CONCLUSIONS: Ultrasmall magnetite particles with a dextran coating were developed; the physical properties of these particles evaluated in vitro are described in this study.

In vitro effectiveness study for hydrodynamic thrombectomy devices of the second generation.

RATIONALE AND OBJECTIVES: To determine the efficacy of clot removal and the amount of applied saline and aspirated fluid and to compare procedure-related particle embolization for the hydrodynamic thrombectomy devices the LF 140 Angiojet (LF 140), the double-lumen Hydrolyser (double HL), and the triple-lumen Hydrolyser (triple HL) in an in vitro flow model. METHODS: Thrombectomy of clots (n = 42) from 7-day-old porcine blood (9.8 g) was performed with the LF 140, the double HL, and the triple HL in a flow model (flow 1 L/min) made of silicone tubes (7 mm inner tube diameter). All catheters were used according to the manufacturer's recommendations. RESULTS: Mean time of thrombectomy ranged from 20 seconds (triple HL) to 58 seconds (LF 140, P < 0.05). Only for the triple HL was remaining thrombus found within the tubes (41 mg). None of the tested devices worked isovolumetrically: the mean ratio of applied saline and aspirated fluid for the devices ranged from 0.79 (triple HL) to 0.89 (double HL, P < 0.05). Mean embolus weight and percentage of embolism from original thrombus were 675 mg/6.7% (LF 140, P < 0.05), 38 mg/0.4% (double HL), and 26 mg/0.3% (triple HL). CONCLUSIONS: Thrombectomy time and embolus weight depend on the device chosen. The ratio of applied to aspirated fluid, indicating the capability to work nearly isovolumetrically, is acceptable for all tested devices. In vitro, the triple HL seems to be the most appropriate device for rapid mechanical, hydrodynamic thrombectomy. Because of the high in vitro particle embolization rate, the LF 140 seems to be strictly limited to small-caliber vessels.

Intravascular ultrasound evaluation of peripheral arterial stent-grafts.

RATIONALE AND OBJECTIVES: To evaluate neointimal hyperplasia, plaque distribution, and morphologic features of peripheral arterial stent-grafts with intravascular ultrasound (IVUS). METHODS: Twenty-three patients with stenoses or occlusions of the pelvic or femoral arteries were treated with 31 stent-grafts. Angiography and IVUS of the stented artery were performed 13.9 +/- 9.7 months after stent implantation. Maximum in-stent restenosis was measured by IVUS. Plaque composition and lesion topography were also assessed. RESULTS: The maximum in-stent restenosis was 53.2 +/- 26.5% for the femoral and 14.2 +/- 10.1 for pelvic arterial stent-grafts. Predilection sites of maximum neointimal tissue accumulation were the edges of the femoral stent-grafts. Only small amounts of neointimal hyperplasia were found in the stent-graft edges. No predilection site for maximum in-stent restenosis was found for the pelvic arterial stent-grafts. CONCLUSIONS: Predilection sites of maximum in-stent restenosis were the edges of femoral stent-grafts in contrast to pelvic stent-grafts. Femoral stent-grafts showed significantly higher graded stenoses with IVUS than iliac stent-grafts. The authors' findings at IVUS did not change the treatment plan in these patients treated with stent-grafts.

Mechanical thrombectomy of acute thrombosis in transjugular intrahepatic portosystemic shunts.

RATIONALE AND OBJECTIVES: To evaluate the feasibility of mechanical thrombectomy with the use of the Amplatz thrombectomy device (ATD) in restoring patency to acutely thrombosed stent-shunts after transjugular intrahepatic portosystemic shunt (TIPS) placement. METHODS: Mechanical thrombectomy with the ATD was performed in 10 consecutive patients with angiographically documented complete thrombosis of the stent-shunt (mean +/- SD, 6.6 +/- 3.4 cm), which occurred an average of 2.8 months (range, 0-11 months) after the TIPS procedure. RESULTS: In all patients, immediate restoration of patency of the stent-shunt was achieved after thrombectomy alone (n = 1), thrombectomy plus percutaneous transluminal angioplasty (PTA; n = 4), and thrombectomy, PTA, and stenting (n = 5). The mean activation time of the ATD was 253 +/- 43 seconds. The pressure gradient for portal decompression decreased from 23 +/- 6 mmHg before to 11 +/- 3 mmHg after the procedure. The primary patency rate was 80% at 3 months and 60% at 11 months. CONCLUSIONS: Mechanical thrombectomy with the ATD in acutely thrombosed TIPS is technically feasible. Mechanical thrombectomy is a potential alternative to thrombolysis.

Theoretical considerations and in vitro results for the development of percutaneous transcatheter balloon embolectomy.

RATIONALE AND OBJECTIVES: To prove the feasibility of performing percutaneous transcatheter embolectomy using a funnel-shaped catheter tip and balloon embolectomy catheters. METHODS: A theoretical model is described to assess the influence of the diameter of an introductory device and coaxially introduced embolectomy catheter. A funnel-shaped catheter tip was attached to 7F, 8F, and 9F introductory sheaths. In vitro embolectomy of 5 g and 12 g thrombi was performed with 3F and 4F embolectomy catheters. RESULTS: The number of extractions required was significantly related to the ratio of the diameters of the sheaths and embolectomy catheter shafts. The combination of a 7F sheath with a 4F embolectomy catheter required the greatest number of extractions (8.4 +/- 1.7). The least number of extractions was needed for the combination of a 9F sheath with 4F and 3F embolectomy catheters (1.6 +/- 0.7 and 1.8 +/- 0.4, respectively). CONCLUSIONS: Our results indicate that percutaneous embolectomy with balloon embolectomy catheters is feasible. However, further research is necessary before the final catheter design is chosen.

Fatal lipid embolism following intraarterial angiography at an early stage of arteriosclerosis.

Intraarterial angiography was performed on a patient with peripheral arterial occlusive disease (Fontaine IIb). No relevant risk factors were known, and a previous angiography had been undertaken without incident. After administration of contrast medium, the patient complained of acute pain in the lower abdomen and both legs, and a sudden rise in blood pressure was observed. The patient subsequently lost consciousness and died within 1.5 h. Postmortem examination showed that death was due to peripheral atheromatous microembolism of lipids, and not cholesterol as is usual in these cases. The differential diagnosis is discussed and a review of the literature is presented.