J.F. Dyet

Treatment of Malignant Superior Vena Cava Obstruction: Metal Stents or Radiation Therapy

PURPOSE The results of treating malignant superior vena cava obstruction by means of percutaneous self-expanding stent insertion or by means of radiation therapy were compared. PATIENTS AND METHODS Seventy-six patients with malignant superior vena cava obstruction who were treated by stent insertion were studied prospectively and 25 patients who were treated by radiation therapy were studied retrospectively. A superior vena cava obstruction score was devised to measure treatment effectiveness. Speed of symptom relief and complications were recorded. End points in the study were recurrent obstruction or death. Asymptomatic survival times were compared by log rank and Mann Whitney tests of significance, as well as Kaplan-Meier analysis. A subgroup of 26 patients who were treated by stent placement only were compared with the radiation therapy group and analyzed separately. RESULTS There were seven complications in the overall stent group, one in the stent-only group, and 25 in the radiation therapy group. Stent insertion provided faster relief of symptoms and significantly greater improvement in the superior vena cava obstruction score than radiation therapy (P < .001, Mann-Whitney U test). A Kaplan-Meier analysis of asymptomatic survival demonstrated that significantly fewer patients in the overall and stent-only groups developed recurrent symptoms (P = .0005 and .001, respectively, log rank test). CONCLUSION This study suggests that percutaneous stent insertion in malignant superior vena cava obstruction fulfills the requirements of a palliative procedure significantly better than radiation therapy and that it should be the procedure of first choice.

Mechanical properties of metallic stents: how do these properties influence the choice of stent for specific lesions?

AbstractPurpose: To assess selected balloon-expandable and self-expanding stents for radial force, flexibility, radio-opacity, and trackability, and to relate these physical characteristics to potential indications for placement. Methods: Force-strain curves were plotted for each stent and the force required to produce 50% luminal narrowing was recorded. The ability of the stent to show elastic recoil following deformation was also noted. Flexibility was measured by bending the stents against a force transducer and recording the force required per degree of flexion. Radio-opacity was measured by comparing each stent against a standard aluminum step wedge. Trackability was measured by testing the ability of the stent on its delivery system to track over angles of 90° and 60°. Results: The balloon-expandable stents showed greater radial strength and radio-opacity but, apart from the AVE Iliac Bridge stent, showed poorer flexibility and trackability. The self-expanding stents showed less radial force but were able to re-expand following deformity. They were generally more flexible and had better trackability but lower radio-opacity. Conclusion: There is no stent which exhibits all the ideal properties required and therefore the interventionist will need to keep a range of stents available if all lesions are to be addressed.

Hepatic Artery Angiography and Embolization for Hemobilia Following Laparoscopic Cholecystectomy

AbstractPurpose: The effectiveness of angiography and embolization in diagnosis and treatment were assessed in a cohort of patients presenting with upper gastrointestinal hemorrhage secondary to hepatic artery pseudoaneurysm following laparoscopic cholecystectomy. Methods: Over a 6-year period 1513 laparoscopic cholecystectomies were carried out in our region. Nine of these patients (0.6%) developed significant upper gastrointestinal bleeding, 5–43 days after surgery. All underwent emergency celiac and selective right hepatic artery angiography. All were treated by coil embolization of the right hepatic artery proximal and distal to the bleeding point. Results: Pseudoaneurysms of the hepatic artery adjacent to cholecystectomy clips were demonstrated in all nine patients at selective right hepatic angiography. In three patients celiac axis angiography alone failed to demonstrate the pseudoaneurysm. Embolization controlled hemorrhage in all patients with no further bleeding and no further intervention. One patient developed a candidal liver abscess in the post-procedure period. All patients are alive and well at follow-up. Conclusion: Selective right hepatic angiography is vital in the diagnosis of upper gastrointestinal hemorrhage following laparoscopic cholecystectomy. Embolization offers the advantage of minimally invasive treatment in unstable patients, does not disrupt recent biliary reconstruction, allows distal as well as proximal control of the hepatic artery, and is an effective treatment for this potentially life-threatening complication.

The use of the wallstent endovascular prosthesis in the treatment of malignant obstruction of the superior vena cava

Seventeen patients (10 men and seven women) aged 48-76 years (mean 63.4) who were suffering from malignant superior vena caval obstruction had Wallstents implanted percutaneously to relieve the obstruction. Fifteen of the patients had previously been treated by radiotherapy or chemotherapy, with either failure to remit or later recurrence. Six patients required thrombolysis prior to stenting. All patients had rapid relief of the obstructive symptoms. This was sustained in 15 patients to date or at death. Two patients, both of whom had pre-stent lysis, developed stent thrombosis following withdrawal of anticoagulation at 4 months and 7 days respectively. Stenting has been shown to be extremely effective at relieving superior vena caval obstruction in these patients and is usually the only method available in this condition when other treatments fail. Whether all patients presenting with malignant superior vena caval obstruction should be stented de novo remains to be proven.

Treatment of chronic iliac artery occlusions by means of percutaneous endovascular stent placement

PURPOSE A retrospective evaluation of outcomes in patients with chronic iliac occlusions treated with insertion of metallic endovascular stents, without previous thrombolysis, on an intention-to-treat basis. MATERIALS AND METHODS Seventy-two patients with chronic iliac occlusion underwent attempted stent placement from either the ipsilateral or contralateral femoral artery. There were 49 men and 23 women. Mean age was 63.1 years (range, 39-88 years). A total of 89 stents were deployed in 67 patients. Follow-up was from 24 to 69 months (mean, 37.5 months). RESULTS Stents were successfully deployed in 67 patients (93%), with two early failures, giving a primary success rate of 90%. There were five significant and four insignificant procedural complications. There were four late failures (all within the first year) and four non-stent-related deaths. CONCLUSION Endovascular stent placement offers an alternative to surgery in the treatment of chronic iliac occlusions.

Long-Term Follow-Up of Percutaneous Balloon Angioplasty in Adult Aortic Coarctation

AbstractPurpose: To assess long-term outcomes following percutaneous transluminal angioplasty (PTA) of congenital aortic coarctation in adults. Methods: Seventeen patients underwent PTA for symptomatic adult coarctation of the aorta. Sixteen patients, with a mean age of 28 years (range 15–60 years), were reviewed at a mean interval after angioplasty of 7.3 years (range 1.5–11 years). Assessment included magnetic resonance imaging (MRI), Doppler echocardiography, and clinical examination. Current clinical measurements were compared with pre- and immediate post-angioplasty measurements. Results: At follow-up 16 patients were alive and well. The patient not included in follow-up had undergone surgical repair and excision of the coarctation segment following PTA. Mean brachial systolic blood pressure for the group decreased from 174 mmHg before angioplasty to 130 mmHg at follow-up (p = 0.0001). The mean gradient had fallen significantly from 50.9 to 17.8 at follow-up (p = 0.001). The average number of antihypertensive drugs required per patient decreased from 0.56 to 0.31 (p = 0.234). No significant residual stenoses or restenoses were seen at MRI. Small but clinically insignificant residual pressure gradients were recorded in all patients using Doppler echocardiography. Complications included one transient ischemic attack at 5 days, one external iliac dissection requiring stent insertion, and a further patient who developed a false aneurysm close to the coarctation site at 12 months which subsequently required surgical excision. Conclusion: PTA of adult coarctation is safe and effective in the long term. Although primary stenting has recently been advocated in the treatment of this condition, our results suggest that PTA remains the treatment of choice.

Vascular imaging and intervention in peripheral arteries in the diabetic patient

Diabetic patients are four times more likely to develop peripheral vascular disease than the general population. This disease is likely to be more aggressive, with five times more patients developing critical limb ischaemia. Early diagnosis and treatment allows up to 80% of these patients to have some form of surgical or endovascular re‐vascularisation. The primary imaging modalities to be used should be duplex ultrasound followed by angiography. Magnetic resonance angiography, however, holds out promise for the future as being a good method of non‐invasive imaging. Endovascular (interventional radiological) procedures have a major role to play in treatment of vascular stenoses and occlusions. Thrombolytic agents can be used to dissolve thrombus within occluded vessels and so restore patency. Percutaneous transluminal angioplasty is of value in dilating the stenotic lesions within the vessels and so restoring normal blood flow. Endovascular stents may be inserted to ensure longer term patency. There is indirect evidence to suggest that the outcomes of endovascular procedures in the diabetic patient are less good than those in the general population, but nevertheless such procedures may save the diabetic patient from primary amputation and allow healing of ischaemic ulcers. Copyright

Long-term follow-up of the Bird's Nest IVC Filter.

AIM This study is a long-term clinical follow-up of the Birds Nest Filter which addresses issues such as caval patency, filter integrity, morbidity and mortality. MATERIALS AND METHODS 78 consecutive patients with Birds Nest Filters inserted between 1989 and 1994 were recalled for clinical assessment and imaging follow-up. Pre- and post-filter medical histories were obtained from the patients and their medical records. They were examined for clinical signs of inferior vena cava occlusion. Imaging follow-up was by plain abdominal radiography, colour duplex ultrasound and computed tomography. RESULTS 52 patients were alive and well at 4-6 years. Thirty-day mortality was 5.1%. Three-year mortality was 19.2%. Recurrent pulmonary embolus occurred in 1.3%. IVC occlusion was demonstrated in 4.7%. No evidence of filter migration was seen. Wire prolapse occurred in 70% on abdominal X-ray and asymptomatic performation of the caval wall in 85.3% on CT. Morbidity and mortality were the same whether the patient was anticoagulated or not. CONCLUSION The Birds Nest Filter is safe and effective in both the short and long term.

The use of the Wallstent in aorto-iliac vascular disease

Forty-three patients had self-expanding endovascular Wallstents inserted for aorto-iliac arterial disease. A total of 59 Wallstents were inserted into 50 iliac arteries. There were 27 males and 16 females with a mean age of 62.51 years. Included in the series were 19 iliac occlusions, 21 severe atheromatous disease of the aortoiliac segment, two severe dissections following conventional angioplasty and one re-stenosis of a previously dilated iliac segment. All of the stents were successfully deployed but there were five significant complications. One case of distal embolism was treated by surgical embolectomy but the other four were treated by an additional percutaneous technique. At follow-up after 6 months all patients remain symptomatically improved. Aorto-iliac stenting is a cost-effective treatment in selected cases of severe aorto-iliac disease.

Percutaneous angioplasty of the superior gluteal artery in the treatment of buttock claudication

A 65-year-old man developed bilateral buttock claudication due to stenosis of the main stem of the left internal iliac artery and stenoses of the left and right superior gluteal branches of the internal iliac arteries. These stenoses were successfully dilated by percutaneous angioplasty using coronary angioplasty equipment. Percutaneous angioplasty is shown to be an effective method of treatment of buttock claudication caused by stenoses of the internal iliac and superior gluteal arteries.