Long-term patency of open revascularization for visceral artery pathologies.

OBJECTIVE: Aim of the study was to evaluate the long-term patency of bypass grafts used to treat occlusive and aneurysmal disease of the visceral arteries. METHODS: A retrospective analysis of our vascular surgery database identified 30 patients (11 men, mean age 59 ± 14 years) who underwent 32 operations for visceral artery pathology between January 1995 and December 2009. Acute mesenteric ischemia (aMI) was present in 10, chronic mesenteric ischemia (cMI) in 14 and visceral artery aneurysm (VAn) in 7 cases. The primary endpoint of this study was vessel patency, secondary endpoints were survival and freedom from reintervention. RESULTS: A total of 46 vessels were revascularized (26 bypass grafts) and additional revascularization procedures (thromboembolectomy, patch plasty, transposition) were performed in 21 cases. In the perioperative period, 6 deaths (5 aMI, 1 cMI) occurred, resulting in a mortality rate of 50 % for aMI and 7 % for cMI. At long-term follow-up (55 months), 22 patients (100 % follow-up) were interviewed and 21 were scheduled for clinical and imaging examinations. Four vessel (3 grafts) occlusions were found in these patients. CONCLUSION: We were able to show that bypass grafting for a visceral artery pathology, although associated with an increased perioperative mortality, is a successful and durable procedure.

Initial experience with a new method of external polyester scaffolding for infrainguinal vein grafts.

OBJECTIVES: This study aims to evaluate the feasibility of external polyester scaffolding in infrainguinal bypass grafting when available vein material is suboptimal due to varicosity or dilatation. Primary objectives were short-term primary patency, assisted primary patency and secondary patency. Secondary objectives were to assess the rate of graft stenoses, infections and other adverse effects related to the use of external scaffolding. MATERIALS AND METHODS: A total of 50 consecutive patients were included in this prospective, multicentre, feasibility study from six centres. The indication for infrainguinal bypass was critical limb ischaemia (64%), severe claudication (34%) or popliteal aneurysm (2%). Indications for the use of the external scaffolding were varicosity of the vein graft, ectatic vein graft or the use of spliced vein grafts with segments of widely differing diameters. Duplex scanning of the graft was done perioperatively and at follow-up visits at 1, 3, 6 and 12 months after operation. RESULTS: Primary patency, assisted primary patency and secondary patency at 6 months were 82.3% (+/-SE 6.2%), 88.6% (+/-SE 4.8%) and 92.1% (+/-SE 4.4%), respectively. Six graft stenoses were detected in duplex surveillance. There were no infections related to polyester mesh. CONCLUSIONS: External scaffolding of infrainguinal vein grafts may be a promising innovation. Early results from this multicentre study show that polyester mesh is safe and feasible adjunct to peripheral revascularization enabling the use of otherwise non-optimal vein grafts with acceptable short-term patency.

Infrapopliteal composite bypass with autologous vein and second generation glutaraldehyde stabilized human umbilical vein (HUV) for critical lower limb ischaemia.

OBJECTIVE: To audit a single center consecutive series of infrapopliteal composite bypasses with second generation glutaraldehyde stabilized human umbilical vein. DESIGN: Retrospective study. PATIENTS: From January 1996 to July 2006 89 femoro-distal bypasses were constructed in 85 patients with HUV and residual vein segments as composite grafts in the absence of sufficient length of autologous vein. METHODS: All patients with infrainguinal bypass operations were registered prospectively. Bypasses to infrapopliteal arteries performed with HUV-composite grafts were reviewed for graft patency, limb salvage, patient survival and possible biodegeneration of the HUV. RESULTS: Early graft thrombosis was noted in 21.3%, necessitating revision surgery. Primary, primary assisted and secondary patency rates were 35%, 40% and 42% respectively, with a limb salvage rate of 87% after 5 years. Graft infection occurred in 7 limbs. Aneurysmal HUV graft degeneration was not detected by duplex scanning. CONCLUSION: HUV-composite bypasses provide acceptable patency and favorable limb salvage rates. Patency was similar to previous series using PTFE-composite bypasses but was significantly inferior to vein bypass. Possible biodegradation of the HUV grafts seems to be of minor clinical relevance.

Operative technique and morbidity of superficial femoral vein harvest.

BACKGROUND: The use of autologous superficial femoral veins (SFV) as an arterial or venous substitute represents a valuable technique in modern vascular surgery with versatile indications. The SFV autografts exhibit excellent control of infection and durable long-term results in terms of graft patency in prosthetic or arterial infections. In cases of elective use of the SFV, duplex ultrasound evaluation of the deep leg vein system should be implemented to confirm the patency of the profunda femoris vein. MATERIAL AND METHODS: The SFV can be harvested distal to the adductor hiatus with a proximal portion of the popliteal vein but should not exceed the level of the knee joint. Formation of a stump of the proximal SFV must be avoided. Simultaneous harvesting of the ipsilateral greater saphenous vein should be avoided to reduce the risk of significant chronic edema. RESULTS: Early postoperative swelling of the donor leg can be expected but resolves spontaneously in most cases. Chronic mild edema of the leg with a possible indication for compression therapy may occur in up to 20 % of cases but severe complications are very rare if the anatomical borders for vein harvesting are respected. Temporary therapeutic anticoagulation after vein harvest is subject to individual decision making. CONCLUSION: Duplex ultrasound is a reliable tool to assess the residual deep and superficial venous system in the long term. Excellent graft function and the tolerable adverse effects of vein harvest on the donor leg justify the use of the SFV in arterial and venous vascular surgery if indicated.

[Classification and treatment of endoleaks after endovascular treatment of abdominal aortic aneurysms]. / Klassifikation und Therapie von Endolecks nach endovaskulärer Behandlung von abdominellen Aortenaneurysmen.

This article describes the classification of endoleaks after endovascular treatment of abdominal aortic aneurysms, thereby summarizing the most important problems of this endovascular technique. The correct classification of endoleaks is a prerequisite for interdisciplinary discussion. It is indispensable for professional reporting of the pathological findings and for the decision making as to the adequate treatment of endoleaks. Irrespective of the types of stent graft and property of the material, five endoleak types are defined in the literature: leakage at the anchor sites (type I); leakage due to collateral arteries (type II); defective stent grafts (type III); leakage due to porosity of the graft material (type IV); and endotension (type V). The causes of endoleaks are discussed and treatment options are reviewed for the diverse pathologic findings.

Diagnosis of perioperative myocardial necrosis following coronary artery surgery--a reappraisal of isoenzyme analysis.

Although the routine determination of CK-MB activity is widely used after coronary artery bypass grafting (CABG), the diagnosis of a perioperative myocardial necrosis remains arbitrary. The intention of the present study was to develop discriminative enzymatic parameters of CK-MB activity in a collective of 710 patients following CABG. Patients were grouped according to their postoperative electrocardiogram (ECG). For each patient, the time activity curve of CK-MB was determined. The total amount of CK-MB was calculated by integrating the area beneath the CK-MB activity curve. Patients presenting with an unchanged postoperative ECG (group I) or a new bundle branch block with uncompromised haemodynamics (group IIa) had an uniform and low profile of CK-MB activity. Serial CK-MB activities as well as the integrated CK-MB area of these two collectives were significantly different (P less than 0.001) from values determined for patients with bundle branch block and low cardiac output (group II b) or patients with new Q waves (group III). After 24h, the 90th percentile of serial CK-MB activities of group I had declined to 18 U/l and was clearly exceeded by 90% of all patients that belonged to either group IIb or III. The 90th percentile of CK-MB areas for group I showed a value of 801 U/l x h. CK-MB areas above 801 U/l x h were seen in about 50% of all patients of group IIa.(ABSTRACT TRUNCATED AT 250 WORDS)

Endovascular treatment of acute bleeding complications in traumatic aortic rupture and aortobronchial fistula.

OBJECTIVE: Herein we report our experience in placement of endovascular stentgrafts in the descending aorta in patients with acute bleeding complications due to traumatic rupture or aortobronchial fistula. METHODS: Six patients (one woman, five men, mean age 47+/-19 years) were treated from September 1995 to February 2000 by implantation of endovascular stentgrafts in the descending aorta. Indications included traumatic ruptures of the aortic isthmus (n=3) and aortobronchial fistulas (n=3). All procedures were performed under general anaesthesia. The implants were introduced under fluoroscopic guidance via the aorta (n=1), the iliac (n=4) or femoral (n=2) artery, respectively. RESULTS: All aortobronchial fistulas and ruptures were sealed up successfully. There was no perioperative morbidity and no procedure-related morbidity except one patient who received aortofemoral reconstruction because of iliac occlusive disease. All patients are alive and well after a mean follow-up of 31 months (range 6-60). Two patients had recurrent hemoptysis, in one case, the patient received a second implant (distal extension), the other patient was managed conservatively. CONCLUSION: Endovascular treatment by a stentgraft is a safe and reliable procedure in the management of acute bleeding complications in patients with aortic rupture or aortobronchial fistulas.

Emergency surgical revascularization following coronary angioplasty: evaluation of operative results by isoenzyme analysis and electrocardiography.

Seventeen patients underwent emergency coronary artery bypass grafting due to balloon catheter induced occlusion or dissection of a major coronary artery. Patients were revascularized within a maximum of 210 min from the onset of ischaemia and received an average of 1.6 distal anastomoses. A perioperative transmural or non-transmural myocardial infarction as diagnosed by CK-MB activity and electrocardiographic patterns occurred in 7 patients (41.2%). One early death resulted in an overall perioperative mortality of 5.9%. Successful preservation of myocardium was demonstrated in 10 patients by a rapid decline of CK-MB activity, no perioperative electrocardiographic changes and no requirement for inotropic support. The incidence of a perioperative myocardial infarction was independent of the anginal status before coronary angioplasty or the angiographic evidence of a complete occlusion versus a dissection. Major ischaemic myocardial complications associated with coronary angioplasty are rare but frequently catastrophic events. Fast surgical intervention is mandatory to prevent myocardial infarction or to limit the extent of injury. The operative outcome can be evaluated by careful analysis of time release curves and cumulative parameters of CK-MB activity.

[Therapy of thromboembolic blockages in the crural arteries: Clinical experience with the Angiojet thrombectomy catheter]. / Therapie thrombembolischer Verschlüsse der Unterschenkelarterien: Klinische Erfahrungen mit dem Angiojet-Thrombektomiekatheter.

UNLABELLED: To investigate the clinical impact of a new hydrodynamic thrombectomy catheter in thromboembolic occlusion of tibial arteries. METHOD: 10 patients with thromboembolic occlusion of all tibial arteries were treated with the Angiojet thrombectomy device in order to reestablish blood flow. Depending on angiographic and clinical results of thrombectomy, additional thrombolysis, PTA, recanalization, or surgical bypass grafting was performed. RESULTS: Antegrade blood flow in at least one tibial artery was reestablished in 6 cases with the thrombectomy device. However, additional treatment modalities were used in order to improve the outcome and to resolve adherent thrombi or to treat vessel stenoses and occlusions: thrombolysis (n = 9), PTA (n = 3), recanalization (n = 1), bypass grafting (n = 3), suction thromboembolectomy (n = 1), replacement of popliteal aneurysm (n = 1). The limb salvage rate was 7/10. The ratio of injected volume to aspiration volume was 1.04 +/- 0.07 indicating that the system works isovolumetrically. The device induced moderate hemolysis with plasma free hemoglobin rising by the factor 12.91 +/- 11.59, (P < 0.01). CONCLUSION: In cases with thromboembolic occlusions of tibial arteries the Angiojet thrombectomy catheter is a valuable addition to the interventional instrumentarium. It works isovolumetrically but induces moderate hemolysis and thereby may compromise renal function. However, in most cases additional treatment modalities are required.

[CT angiography in arterial occlusive disease: comparison of 3 rendering techniques]. / CT-Angiographie bei arterieller Verschlusskrankheit: Vergleich von 3 Rekonstruktionsverfahren.

PURPOSE: To evaluate different rendering techniques of CT data for the assessment of long vessel segments in peripheral vascular occlusive disease. MATERIAL AND METHODS: 40 CT angiograms (aortoiliac: n = 20, leg arteries: n = 20) were viewed using three different rendering techniques: 1, maximum intensity projection (MIP); 2, volume rendering (VR); 3, shaded surface display (SSD). CT angiograms were obtained in 6 or 8 projections. Axial cross-section images were analysed using an interactive cine mode. Intraarterial DSA was the standard in all cases. RESULTS: The sensitivities for the diagnosis of occlusive disease were 100% (cross-section images), 94% (MIP), 91% (VR) and 93% (SSD). The specificities were 100%, 99%, 99% and 99%, respectively. For the accurate grading of high-grade (> 75%) stenoses, the sensitivities were 85% (cross-section images), 62% (MIP), 44% (VR) and 35% (SSD). Specificity was 99% for all techniques. CONCLUSIONS: CTA is accurate in occlusive disease. Interactive viewing of cross-section images is the most accurate technique. MIP is superior to VR in the imaging of high-grade stenoses because contrast-to-noise ratio is high and thresholding is not necessary.

[Influence of endoleaks on aneurysm volume and hemodynamics after endovascular aneurysm repair]. / Einfluss von Typ-II-Endoleaks auf die Grössenänderung und Hämodynamik experimenteller Aortenaneurysmen nach endovaskulärer Therapie.

PURPOSE: To evaluate the aneurysm volume and the intra-aneurysmatic pressure and maximal pressure pulse (dp/dtmax) in completely excluded aneurysms and cases with endoleaks. MATERIALS AND METHODS: In 36 mongrel dogs, experimental autologous aneurysms were treated with stent-grafts. All aortic side branches were ligated in 18 cases (group I) but were preserved in group II (n = 18). Aneurysm volumes were calculated from CT scans before and after intervention, and from follow-up CT scans at 1 week, 6 weeks and 6 months. Finally, for hemodynamic measurements, manometer-tipped catheters were introduced into the excluded aneurysm sac (group I and II), selectively in endoleaks (group II), and intraluminally for aortic reference measurement. Systemic hypertension was induced by volume load and pharmacologic stress. Pressure curves and dp/dt were simultaneously recorded and the ratios of aneurysm pressure to systemic reference pressure calculated. RESULTS: At follow-up, type-II. endoleaks were excluded in all cases of group I by selective angiography. In contrast, endoleaks were evident in all cases of group II. Volumetric analysis of the aneurysms showed a benefit for group I with an improved aneurysm shrinkage: DeltaVolume + 0.08 %, - 1.62 % and -9.76 % at 1 week, 6 weeks and 6 months follow-up (median, group I), compared to + 1.43 %, + 0.67 %, and - 4.04 % (group II), p < 0.05. In case of complete aneurysm exclusion the ratio of systolic aneurysm pressure to systemic reference pressure was 0.662, 0.575 and 0.385 (median) at 1 week, 6 weeks and 6 months. The corresponding dp/dtmax ratios were 0.12, 0.07 and 0.04, respectively. However, within endoleaks selective measurements showed significantly increased pressure load: the ratios of systolic endoleak pressure to systemic reference pressure and the corresponding ratios for dp/dtmax were 0.882 and 0.913 (median), respectively. These hemodynamic findings were linear from hypotension, physiologic blood pressure to hypertension. CONCLUSION: Occlusion of all aortic side branches of an aneurysm prior to stent-grafting reduces endoleaks and promotes aneurysm shrinkage. Complete aneurysm exclusion significantly reduces systolic pressure and dp/dt max. In contrast, endoleaks showed nearly systemic pressure load and undamped pulsatility.

[Endovascular therapy of abdominal aortic aneurysm: results of a mid-term follow-up]. / Endovaskuläre Therapie von abdominellen Aortenaneurysmen: Klinisch-radiologische Ergebnisse im mittelfristigen Verlauf.

PURPOSE: Prospective study to evaluate clinical results and complications of endovascular abdominal aortic aneurysm treatment in a mid-term follow-up. MATERIALS AND METHODS: A total of 122 patients (9 females, 113 males, average age 70.9 +/- 7.9 years) with abdominal aortic aneurysms were treated with stent grafts (53 Vanguard or Stentor endografts, 69 Talent endografts). Group I consisted of 40 patients who had all aortic tributaries of the aneurysm sac occluded prior to endovascular grafting, either spontaneously by parietal thrombosis or by selective coil embolization of the respective ostia preserving collateral circulation distal to the vessel occlusion. Group II consisted of 82 patients and included all cases without or with incomplete coil embolization with at least one patent vessel. Stent grafting was performed in general anesthesia in the first 21 patients, followed by peridural anesthesia in 15 cases, and local anesthesia with conscious sedation in 86 cases. The results were evaluated with Spiral-CT, MRI and radiographs of the endovascular graft, with follow-up examinations obtained at 3, 6, 12 months, and every year. RESULTS: Implantation was successfully completed in all cases without primary conversion surgery, laparotomy, or any significant complication. Mean follow-up was 29 +/- 21 months (maximum 84 months). The 30-day mortality was 0.8 % due to a myocardial infarction 3 days after discharge from the hospital. A total of 47 re-interventions were performed in 29 patients (23.8 %), with 35 re-interventions in 18 cases with Vanguard or Stentor endografts and 12 re-interventions in 11 patients with Talent endografts. 23 percutaneous re-interventions included distal graft extension (n = 11), Wallstents for kinking and limb stenosis (n = 3), and secondary coil embolization of collateral vessels (n = 9). 24 surgical re-interventions included proximal graft extension (n = 6), new endovascular grafts (n = 3), surgical clipping of lumbar and mesenteric artery branches for type-II endoleaks following ineffective secondary coil embolization (n = 1), and femorofemoral crossover bypasses (n = 4). A total of 10 secondary conversion operations were performed because of damage to the membrane (n = 4; 3 Vanguard endografts, 1 Talent endograft), significant caudal migrations (n = 5; 4 Vanguard endografts, 1 Talent endograft) associated with type-I endoleaks (n = 2), limb occlusion (n = 1), disconnection of graft components (n = 1), and significant endoluminal thrombus deposits (n = 1). One patient, who was followed for 82 months, suffered from a significant endoleak for 10 months with increasing aneurysm diameter but he refused surgery. He was admitted with aneurysm perforation and was successfully operated with aortic graft replacement. Compared to group II, the incidence and size of endoleaks was reduced in group I (incidence 19.2 % versus 29.9 %, p < 0.05). Group I demonstrated significantly better aneurysm shrinkage at 36 months follow-up (Delta sagittal diameter - 11.1 +/- 8.4 mm versus - 4.9 +/- 6.2 mm, p < 0.05). CONCLUSION: In selected patients, endovascular aneurysm treatment is an effective alternative to open surgery. It is safely performed in local anesthesia with low mortality rate and a low number of acute complications. Intermediate follow-up revealed re-interventions in around one quarer of all patients, especially when Vanguard or Stentor endografts were implanted. Primary coil embolization of all aortic branches prior to endovascular grafting improves clinical outcome. Insufficient proximal fixation and its consecutive complications remains a major problem of this method.

[CT angiography versus intra-arterial DSA in abdominal aortic aneurysms]. / CT-Angiographie versus intraarterielle DSA bei Bauchaortenaneurysmen.

PURPOSE: To evaluate if CT angiography is able to image all features necessary for the preoperative planning of abdominal aortic aneurysms (accessory renal arteries, stenoses or occlusions of renal and iliac arteries, patency of inferior mesenteric artery). METHODS: CT angiography and DSA were performed on 27 patients with abdominal aortic aneurysms. CT angiography was performed using a protocol that covered the abdominal aorta and the pelvic arteries with a single spiral acquisition (contrast dose: 150 ml, collimation: 5 mm, table feed: 7.5 mm/s, increment of reconstruction: 2 mm). Maximum intensity projections (MIP) and axial scans were compared with the results of intraarterial DSA. RESULTS: Using axial scans and subvolume MIP, CTA accurately defined 7/8 accessory renal arteries, 13/13 occlusions and 9/12 high grade stenoses of renal and pelvic arteries. High-grade stenoses of the iliac arteries were underestimated in two cases and overlooked in one case. CT angiography was superior to DSA in imaging the inferior mesenteric artery. CT angiography precisely diagnosed 33 aneurysms of the iliac, renal and coeliac arteries. CONCLUSION: CT angiography using a single administration of intravenous contrast may replace preoperative DSA in most cases of abdominal aortic aneurysm.

[Popliteal aneurysms: clinical aspects and diagnosis]. / Das Popliteaaneurysma: Klinik und Diagnostik.

PURPOSE: To identify clinical and radiological features allowing an early diagnosis of popliteal aneurysms. MATERIAL AND METHODS: History, clinical features and radiological findings of 23 patients with 37 aneurysms were reviewed. RESULTS: 14 patients presented with a history of a sudden onset of rest pain localised in the calf or foot. Arteriography found popliteal artery occlusion in 12 of them. Amputation was necessary in one patient in spite of immediate diagnosis and therapy. In two cases embolisation of the tibial vessels caused intermittent claudication. In at least 7 patients the underlying disease was not suspected until arteriography was performed. In 16/23 patients the presence of thrombus prevented direct visualisation of the aneurysm and there were only secondary angiographic signs of the underlying condition. Thus, arteriography may fail to diagnose popliteal aneurysms. In 21/22 cases colour Doppler sonography was quick and accurate in the assessment of patent and thrombosed aneurysms. CONCLUSION: In any patient with ischaemic symptoms of the lower extremity a thorough palpation of the popliteal fossa should be performed. In patients with a prominent popliteal pulse, in pulseless popliteal tumours and in patients arteriographically shown to have popliteal artery occlusion, a sonographic study of both popliteal fossae should be performed.

[Pressure load of the aneurysm sac after endovascular treatment of aortic aneurysm]. / Druckentlastung im Aneurysmasack nach endovaskulärer Therapie von Aortenaneurysmen.

PURPOSE: Stent grafting of aortic aneurysms should result in relief of pressure within the excluded aneurysmal sac, however confirming data are not available. This study evaluates the intra-extraluminal pressure translation and translation of maximum pressure increase (dp/dtmax) into the excluded aneurysmal sac after endovascular treatment of experimental aortic aneurysms. MATERIALS AND METHODS: Experimental autologous aneurysms were created surgically using a patch from the sheath of the rectus abdominis muscle in 12 mongrel dogs. After 12 weeks reconvalescence, endovascular treatment was performed viafemoral access using dacron-covered nitinol stents. Spiral CT and angiography were performed at one week and six weeks follow-up and 6 animals each. Laparotomy was performed for hemodynamic measurements. A manometer-tipped catheter was introduced into the excluded aneurysmal sac. A second manometer-tipped catheter was placed intraluminally within the stent graft. Pressure curves and their first derivative dp/dt were simultaneously recorded to calculate the intra-extraluminal transmembraneous pressure transmission. RESULTS: At one week follow-up systolic blood pressure and mean blood pressure were significantly reduced by factors of 0.60 +/- 0.17 (p < 0.01) and 0.78 +/- 0.3 (p < 0.05), respectively in the excluded aneurysm sac. The maximal pressure increase, dp/dt max, was considerably reduced by a factor of 0.06 +/- 0.05 (p < 0.01). However, the diastolic blood pressure was not significantly changed. There were no hemodynamic differences between one and six weeks follow-up. CONCLUSION: In experimental aortic aneurysms, endovascular treatment with stent grafts significantly reduces the systolic peak pressure and dp/dt max in the excluded aneurysmal sac, and thereby significantly reduces the wall stress in the diseased aneurysm wall. Despite complete exclusion of the aneurysm, a considerable pressure load remains in the excluded aneurysmal sac.

[Emergency endovascular treatment of acute aortic diseases]. / Endovaskuläre Behandlung akuter Erkrankungender thorakalen Aorta.

PURPOSE: To investigate the safety and efficacy of emergency treatment of acute aortic diseases with endovascular stent grafts. METHODS: In 11 patients (median age 55 years, range 18 - 85) with acute complications of descending aortic diseases endovascular emergency treatment was performed: traumatic aortic rupture (n = 4), penetrating ulcer with aortobronchial fistula or hematothorax (n = 4), acute type B dissection (n = 2, one with penetration, one with subacute mesenteric ischemia), and symptomatic aneurysm of the thoracic aorta (n = 1) with pain and diameter progression. 15 stent grafts were implanted (Talent n = 11, Vanguard/Stentor n = 4). Stent extension was necessary in 4 cases. In 2 cases graft extension was done during the first procedure (due to distal migration and due to the total length of the aortic aneurysm). In 2 cases graft extension was performed 5 days (due to a new aortic ulcer at the proximal stent struts) and 5 months after the initial procedure (recurrent aortobronchial fistula due to aneurysm progression). 14 of 15 implantations required general anesthesia, one symptomatic thoracic aneurysm was performed in local anesthesia and sedation. RESULTS: 14 of 15 graft procedures were performed using the femoral or iliac approach. One procedure required aortofemoral bypass grafting due to extensive arteriosclerotic stenosis and the stent graft was inserted via the bypass graft. The orifice of the subclavian artery was crossed with bare stent struts in 4 cases without neurological complications. Median follow-up is 27 months (range 6 to 72 months). In traumatic aortic ruptures, immediate sealing of bleeding was achieved and follow-up is inconspicuous at a maximum of 72 months. In cases of aortobronchial fistulas, follow-up is satisfactory (maximum 72 months) despite the necessity for reintervention and graft extension. In one acute type B dissection retrograde dissection of the aortic arch occurred during stent release with stable disease during follow-up without neurological complications. In one type B dissection with mesenteric ischemia the mesenteric blood flow was restored. A second look operation confirmed pulsatile flow in the mesenteric trunk but a total necrosis of the small intestine and the patient consequently died. CONCLUSION: Endovascular treatment is safe and effective for emergency treatment of life-threatening complications in selected acute aortic syndromes. Mid-term results are encouraging, however, regular follow-up is mandatory to recognize late complications of the stent graft.

[Intravascular therapy of aortic aneurysms: initial clinical results]. / Endovaskuläre Therapie aortaler Aneurysmen: erste klinische Ergebnisse.

PURPOSE: A clinical study aiming at examining the implantation technique and the clinical results of a new vascular prosthesis in endovascular therapy of aneurysms of the aorta. MATERIAL AND METHODS: In 21 patients (20 men of 55 to 87 years of age, average age 70 years) with aneurysms of the infrarenal abdominal aorta (AAA n = 19) and the thoracic aorta (n = 2), a self-expanding nitinol stent with outer Dacron sheath (tubular prosthesis n = 4; bifurcation prosthesis n = 17) was implanted by means of an F-18 introductory set after surgical opening of the inguinal artery. RESULTS: By means of the 4 tubular prostheses and 13 of the 17 bifurcation prostheses the aneurysm was bypassed completely. In 4 cases residual perfusion through leaks (n = 3) or collateral blood supply (n = 1) was seen. In 6 patients 7 complications occurred which did not require to be operated on. No patient died in consequence of the surgical intervention or during the hospital stay. Follow-ups up to 8 months after surgery did not reveal any late complications to date. CONCLUSIONS: Endovascular implantation of vascular prostheses is a promising new method for interdisciplinary treatment of aneurysms of the aorta.

[Comparison of contrast-enhanced MR angiography of the aortoiliac vessels using a 1.0 molar contrast agent at 1.0 T with intra-arterial digital subtraction angiography]. / Ergebnisse der kontrastverstärkten MR-Angiographie der aortoiliakalen Gefässe mit einem 1-molaren Kontrastmittel bei 1,0 T: Vergleich zur i. a. DSA.

PURPOSE: To evaluate the diagnostic accuracy of contrast-enhanced MR angiography (CE-MRA) using a 1.0 molar contrast agent at 1.0 T for the diagnosis of abdominal aortic aneurysms and stenoses of renal or iliac arteries in comparison to intraarterial digital subtraction angiography (DSA). MATERIALS AND METHODS: A total of 19 patients with the suspicion of abdominal aortic aneurysm or stenosis of renal or iliac arteries were examined with CE-MRA at 1.0 T. Intra-arterial DSA served as reference in all cases. After test bolus tracking, 10 or 8 ml of the 1.0 molar contrast agent Gadobutrol corresponding to a dose of 0.1 - 0.15 mmol/kg bw were injected and imaging performed using a FLASH-3D sequence. To evaluate the interobserver-variability, the blinded images were analyzed by two radiologists. Besides the rating of overall image quality on a 4-point-scale, the images were evaluated for aneurysms and arteriosclerotic lesions with a stenosis of < 50 % or > 50 % or occlusion. RESULTS: A total of 144 segments were analyzed. The mean value of the CE-MRA image quality was 3.4 on a 4-point-scale. The sensitivity of CE-MRA in depicting relevant pathological findings was 96 % and the specificity 99 %. The positive predictive value was 96 % and the negative predictive value 99 %. Inter-observer variability was low with a kappa value of 0.82. CONCLUSION: CE-MRA using a 1.0 molar contrast agent at 1.0 T enables an excellent diagnosis or exclusion of pathologies of the aortoiliac vessels.

[Endovascular aneurysm treatment: Radiological and macropathological findings of the endoluminal surface of modular stent grafts]. / Endovaskuläre Aneurysmatherapie: Radiologisch-makropathologische Befundkorrelation der endoluminalen Oberfläche einer modularen Stentprothese.

PURPOSE: Characterization of the endoluminal surface of a modular stent graft and correlation of macropathological findings with results of radiological methods. METHODS: Aneurysms of the infrarenal aorta were created in 36 mongrel FBI dogs using autologous material. Endovascular treatment was performed with modular stent grafts using two polyester-covered nitinol stents connected with overlap within the aneurysm. Follow-up was 1 and 6 weeks, and 6 months for 12 animals, respectively. Results were documented using sonography, intravascular ultrasound (IVUS), spiral CT, MRI, and digital subtraction angiography (DSA). After fixation, the aorta was prepared and incised lengthwise. Before histopathological work-up, the different segments were macropathologically characterized and correlated with the respective findings of the radiological methods. RESULTS: 4 cases showed high grade stenosis within the stent grafts and graft occlusion occurred in two cases. The connection sites of these modular stent grafts showed steps and partial separation of the graft components was causative in 5 of these cases. Migration of graft components occurred in three cases, one of them with complete disconnection of the modular device. Irregulartities and deposits on the endoluminal surface were systematically underestimated with all radiological techniques used. IVUS showed moderate concordance concerning deployment and unfolding of the stent graft, however, irregularities of the endoluminal surface were systematically underestimated. Concordance of MRI, sonography, and CT was worse. Contrast-enhanced T1-w MRI detected endoluminal deposits with moderate concordance. However, the thickness of deposits was underestimated. DSA, IVUS, and CT showed only poor concordance with macropathological findings. CONCLUSIONS: The connection site of modular stent grafts predisposes to stenosis, occlusion, and disconnection of the modular device. Stent deployment and unfolding of the membrane might be examined with IVUS. MRI is useful for detecting endoluminal deposits and stenosis. However, radiological methods will underrate irregularities and deposits of the endoluminal surface.

Arterial embolism to the upper extremity in a patient with factor V Leiden mutation (APC resistance)--a case report and review of the literature.

Factor V Leiden mutation has emerged as one of the leading abnormalities in inherited blood coagulation disorders, resulting in a markedly increased risk for deep leg vein thrombosis. A 24-year-old woman presented with acute onset of critical ischemia of her left thumb and index finger. Intraarterial angiography revealed an embolus in the distal radial artery and a thrombotic occlusion of the digital artery of the thumb and index finger. Immediate therapy encompassed a selective surgical embolectomy of the distal radial artery followed by a local intraarterial lysis that was continued for 3 days. Additionally, therapeutic anticoagulation and vasodilating drugs (prostaglandin E) were administered. Within 2 days, capillary refill reappeared and the initial loss of sensory function at the tip of the thumb and index finger diminished. A screening test for thrombophilic disorders led to the diagnosis of a heterozygous mutation of factor V (Leiden mutation). Arterial thromboembolic events of factor V Leiden mutation are rare and have to date been described only in the supraaortic and coronary circulation. Therefore, the arterial embolism to the left hand presented in this report constitutes a rarity that could be successfully salvaged by the combined use of a vascular surgical procedure and intensified medical management.