Duncan F. Ettles

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.

Managing inadvertent arterial catheterization during central venous access procedures.

AbstractPurpose: Approximately 200,000 central venous catheterizations are carried out annually in the National Health Service in the United Kingdom. Inadvertent arterial puncture occurs in up to 3.7%. Significant morbidity and death has been reported. We report on our experience in the endovascular treatment of this iatrogenic complication. Methods: Retrospective analysis was carried out of 9 cases referred for endovascular treatment of inadvertent arterial puncture during central venous catheterization over a 5 year period. Results: It was not possible to obtain accurate figures on the numbers of central venous catheterizations carried out during the time period. Five patients were referred with carotid or subclavian pseudoaneurysms and hemothorax following inadvertent arterial catheter insertion and subsequent removal. These patients all underwent percutaneous balloon tamponade and/or stent-graft insertion. More recently 4 patients were referred with the catheter still in situ and were successfully treated with a percutaneous closure device. Conclusion: If inadvertent arterial catheterization during central venous access procedures is recognized and catheters removed, sequelae can be treated percutaneously. However, once the complication is recognized it is better to leave the catheter in situ and seal the artery percutaneously with a closure device.

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

Fibroid Calcification after Uterine Artery Embolization: Ultrasonographic Appearance and Pathology

PURPOSE To describe the ultrasonographic (US) appearance of fibroid calcification occurring after uterine artery embolization (UAE) and discuss its etiology and pathology. MATERIALS AND METHODS Twenty-seven of a total of 38 patients were followed up clinically and with duplex US for longer than 6 months after UAE for uterine fibroids. At US, changes in uterine size, fibroid vascularity, and morphology have been recorded. Pathologic studies were performed by one of the authors on resected specimens from a different cohort of patients, at intervals ranging from 4 months to 1 year after UAE. RESULTS Twenty patients reported complete resolution of symptoms. In 16 of these, a reduction in fibroid volume of 70%-85% was recorded and, at US, the development of a peripheral hyperechoic rim around an increasingly hypoechoic fibroid was noted. Computed tomography in two patients revealed it to be a rim of calcium. Histologic studies in a different cohort of patients who had undergone hysterectomy at variable intervals after UAE demonstrated early aggregation of polyvinyl alcohol (PVA) particles, an intermediate giant cell inflammatory reaction, and calcification in the periphery of the infarcted fibroid at 6-12 months. CONCLUSION Calcification is the end stage of hyaline degeneration. However, its peripheral location is unlike that of natural fibroid involution and hyaline necrosis. Pathologic studies in resected human fibroids after embolization suggest that its development is the end result of aggregation of PVA particles in peripheral fibroid arteries.

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.

Acute aortic syndrome: CT findings

Acute aortic syndrome (AAS) is a constellation of potentially life-threatening acute aortic diseases. The spectrum includes penetrating atherosclerotic ulcer, intramural haematoma, dissection, and unstable thoracic aneurysm. AAS cannot be reliably diagnosed clinically and multidetector computed tomography (MDCT) has revolutionized the diagnosis and management of this group of conditions in the acute setting due to its availability, speed, and accuracy. The purpose of this review is to illustrate key MDCT findings of AAS. Imaging techniques, radiological findings, and common pitfalls are also discussed.

Penetrating atherosclerotic ulcer of the aorta: A continuing debate

Aortic penetrating atherosclerotic ulcer (PAU) is a relatively common incidental finding on thoracic computed tomography (CT) examinations. This is likely to relate to the steady increase in the number of CT examinations performed and also due, in part, to the increasing age of the general population. There is as yet no consensus on the management of incidental PAUs in asymptomatic patients. This article aims to review the literature and discuss the natural history, prognosis, and management of incidental PAU.