Dijk, L.C. van

A comparative study of myocardial injury during conventional and endovascular aortic aneurysm repair: Measurement of cardiac troponin T and plasma cytokine release (Article)

2010-03-01T00:00:00Z

Background: Major aortic surgery results in significant haemodynamic and oxidative stress to the myocardium. Cytokine release is a major factor in causing cardiac injury during aortic surgery. Endovascular aortic aneurysm repair (EVAR) has the potential to reduce the severity of the ischaemia reperfusion syndrome and its systemic consequences. Aim: The aim of this study was to investigate the occurrence of myocardial injury during conventional and endovascular abdominal aortic aneurysm repair using measurement of the myocardial-specific protein, cardiac troponin T. Interleukin-6 was also measured in both groups and haemodynamic responses to surgery assessed. Methods: Nine consecutive patients undergoing conventional infra-renal aortic aneurysm surgery were compared with 13 patients who underwent EVAR. Patients were allocated on the basis of aneurysm morphology and suitability for endovascular repair. Results: Patients undergoing open repair had significantly more haemodynamic disturbance than those having endovascular repair (mean arterial pressure at 5 min following unclamping or balloon deflation: open (69.6 + 3.3 mmHg); endovascular (86 + 4.4 mmHg), P < 0.05 vs. pre-op). Troponin T levels at 48 h post-operatively were higher in patients who underwent open repair (open 0.164 + 0.1 ng/ml; endovascular 0.008 + 0.0005 ng/ml, P < 0.04). Significantly more patients in the open repair group had troponin T levels > 0.1 ng/l when compared with the endovascular group (P < 0.01, χ 2 test) Conclusion: Endovascular aortic surgery produces significantly less myocardial injury than the open technique of aortic aneurysm repair.

Complex liver trauma with bilhemia treated with perihepatic packing and endovascular stent in the vena cava (Article)

2009-08-01T00:00:00Z

Subtotal adrenalectomy (Br J Surg 2008; 95: 1075-1076) (Article)

2008-12-01T00:00:00Z

Multi-detector row CT angiography in patients with abdominal angina. (Article)

2004-01-01T00:00:00Z

Abdominal angina (AA) is an infrequently occurring syndrome characterized by postprandial abdominal pain due to reduced blood flow to organs in the territory of the celiac trunk, superior mesenteric artery (SMA), and inferior mesenteric artery. Multi-detector row computed tomographic (CT) angiography with four- or 16-row scanners has become a primary tool for the evaluation of patients with suspected steno-occlusive diseases of the abdominal vessels. In patients with suspected AA, multi-detector row CT angiography can help evaluate the presence and degree of stenosis in the celiac trunk and SMA, demonstrate the collateral circulation, and help exclude other causes of vascular obstruction. It also allows visualization of small vessels and of vessel wall abnormalities in the absence of significant stenosis. Vessels with a complex anatomic configuration can easily be visualized with proper postprocessing techniques. This modality can also be used to follow up patients who have undergone percutaneous interventional treatment. Limitations include the lack of dynamic representation of flow abnormalities and difficulty in evaluating heavily calcified vessels. Nevertheless, multi-detector row CT angiography with appropriate postprocessing techniques is highly effective for the diagnosis, evaluation, and treatment of suspected AA. Additional studies will help further evaluate the performance and applications of this modality.

Shrinkage of the distal renal artery 1 year after stent placement as evidenced with serial intravascular ultrasound (Article)

2002-01-01T00:00:00Z

The objective of this study was to determine the quantitative intravascular ultrasound (IVUS) and angiographic changes that occur during 1 year follow-up after renal artery stent placement, given that restenosis continues to be a limitation of renal artery stent placement. 38 consecutive patients with symptomatic renal artery stenosis treated with Palmaz stent placement were studied prospectively. IVUS and angiography were performed at the time of stent placement and at 1 year follow-up. At follow-up, angiographic restenosis was seen in 14% of patients. The lumen area in the stent, seen with IVUS, was significantly decreased from 24+/-5.6 mm(2) to 17+/-5.6 mm(2) (p<0.001) solely due to plaque accumulation. The distal main renal artery showed a significant decrease in lumen area owing to a significant vessel area decrease from 39+/-14.0 mm(2) to 29+/-9.3 mm(2) (p<0.001) without plaque accumulation. Angiographic analysis confirmed this reduction in luminal diameter and showed that the distal renal artery diameter at follow-up was significantly smaller than before stent placement (86+/-23.0% vs 104+/-23.9% of the contralateral renal artery diameter; p=0.003). Besides plaque accumulation in the stent, unexplained shrinkage of the distal main renal artery was evidenced with IVUS and angiography 1 year following stent placement.

A precious metal alloy for construction of MR imaging-compatible balloon-expandable vascular stents (Article)

2001-01-01T00:00:00Z

The authors developed ABI alloy, which mechanically resembles stainless steel 316. The main elements of ABI alloy are palladium and silver. Magnetic resonance (MR) images and radiographs of ABI alloy and stainless steel 316 stent models and of nitinol, tantalum, and Elgiloy stents were compared. ABI alloy showed the least MR imaging artifacts and was more radiopaque than stainless steel 316. ABI alloy has the potential to replace stainless steel 316 for construction of balloon-expandable MR imaging-compatible stents.

Stent placement for renal arterial stenosis: where do we stand? A meta-analysis (Article)

2000-01-01T00:00:00Z

PURPOSE: To perform a meta-analysis of renal arterial stent placement in comparison with renal percutaneous transluminal angioplasty (PTA) in patients with renal arterial stenosis. MATERIALS AND METHODS: Studies dealing with renal arterial stent placement (14 articles; 678 patients) and renal PTA (10 articles; 644 patients) published up to August 1998 were selected. A random-effects model was used to pool the data. RESULTS: Renal arterial stent placement proved highly successful, with an initial adequate performance in 98% and major complications in 11%. The overall cure rate for hypertension was 20%, whereas hypertension was improved in 49%. Renal function improved in 30% and stabilized in 38% of patients. The restenosis rate at follow-up of 6-29 months was 17%. Stent placement had a higher technical success rate and a lower restenosis rate than did renal PTA (98% vs 77% and 17% vs 26%, respectively; P <.001). The complication rate was not different between the two treatments. The cure rate for hypertension was higher and the improvement rate for renal function was lower after stent placement than after renal PTA (20% vs 10% and 30% vs 38%, respectively; P <.001). CONCLUSION: Renal arterial stent placement is technically superior and clinically comparable to renal PTA alone.

Intravascular ultrasound evidence for coarctation causing symptomatic renal artery stenosis (Article)

1999-01-01T00:00:00Z

BACKGROUND: A recent study of human cadaveric renal arteries revealed that renal artery narrowing could be due not only to atherosclerotic plaque compensated for by adaptive remodeling, but also to hitherto undescribed focal narrowing of an otherwise normal renal arterial wall (ie, coarctation). The present study investigated whether vessel coarctation could be identified in patients with symptomatic renal artery stenosis (RAS). METHODS AND RESULTS: Consecutive symptomatic patients with angiographically proven atherosclerotic RAS who were referred for stent placement were studied by 30-MHz intravascular ultrasound before intervention (n=18) or after predilatation (n=18). Analysis included assessment of the media-bounded area and plaque area (PLA) at the most stenotic site and at a distal reference site (most distal cross-section in the main renal artery with normal appearance). Coarctation was considered present whenever the target/reference media-bounded area was

Three-dimensional ultrasound study of carotid arteries before and after endarterectomy; analysis of stenotic lesions and surgical impact on the vessel (Article)

1998-01-01T00:00:00Z

BACKGROUND and PURPOSE: It has been proved that symptomatic patients with severe carotid stenosis benefit from endarterectomy. Currently used methods for quantitation of the severity of carotid stenosis have limitations, and the impact of endarterectomy on the operated region of carotid artery remains unknown. The purpose of this study was to examine the accuracy of a 3-D ultrasound system for quantitation of stenotic lesions and to evaluate changes in regional vessel volume and cross-sectional area after carotid endarterectomy. METHODS: We studied 14 patients with both carotid angiography and 3-D ultrasound. Of 13 patients who underwent surgery, 12 were reexamined with 3-D ultrasound after surgery. The length and volume of 20 randomly selected plaques were measured from 3-D data sets. The severity of stenosis was quantified by 3-D ultrasound using both a diameter method and an area method on cross-sectional views at the most stenotic site; the results were then compared with those from carotid angiography. The segmental vessel volume and average cross-sectional area of the operated artery both before and after endarterectomy were measured from 3-D ultrasound data. RESULTS: Good correlation was obtained between 3-D ultrasound and carotid angiography in quantitative analysis of carotid stenosis (SEE=12.4%, r=0.76, and mean difference=7.0+/-12.3% with the diameter method; SEE=10.5%, r=0.82, and mean difference=1.8+/-10.5% with the area method by 3-D ultrasound). 3-D ultrasound had excellent reproducibility and small intraobserver and interobserver variability in plaque length and volume measurements. No significant changes in segmental vessel volume and average cross-sectional area of the operated artery were observed after surgery in patients with suture closure. However, a significant increase in segmental vessel volume was obtained in patients with polyfluorethylene patches applied to the surgical opening of the artery. CONCLUSIONS: 3-D ultrasound can be used for both qualitative and quantitative analysis of plaques in the carotid artery and to detect and quantify significant carotid stenosis. Its volumetric potential has important clinical implications in serial follow-up studies for observing the progression or regression of stenotic lesions and for evaluating the outcome of interventional procedures such as endarterectomy or stent placement.

'Closed' in Situ Vein Infrainguinal Bypass (Doctoral Thesis)

1996-11-06T00:00:00Z

The autologous greater saphenous vein is considered to be the best bypass material for below knee femoropopliteal and femorocnual arterial reconstructions . . The history of the greater saphenous vein arterial bypass in humans started in 1949, with its first introduction by Kunlin. Upto 1959, when Rob performed the first in situ saphenous vein bypass, the reversed saphenous vein technique of Kunlin was the standard procedure. The first publication about the in situ bypass was written in 1962 by Karl Victor Hall. After tlus preliminary report, several optimistic reports, written by Hall, ConnOlly, May and Samuel followed. Despite the promissing results, the in situ bypass technique only achieved minimal popularity, mainly in Europe. It was not before Leather, Powers and Karmody published their historical publication in 1979 that the in situ bypass really was considered to be a worthy alternative for the "reversed" technique. Their excellent results received worldwide attention and contributed to the adoption of the in situ bypass technique in many major vascular surgery departments during the early eighties (including those in the USA).