Long-term follow-Up of percutaneous balloon angioplasty in adult aortic coarctation.

PURPOSE: 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.

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

PURPOSE: 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 degrees and 60 degrees. 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.

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

AIM: This study is a long-term clinical follow-up of the Bird's Nest Filter which addresses issues such as caval patency, filter integrity, morbidity and mortality. MATERIALS AND METHODS: 78 consecutive patients with Bird's 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 Bird's Nest Filter is safe and effective in both the short and long term.

Directional atherectomy in iliac stent failure: clinical technique and histopathologic correlation.

PURPOSE: To assess the feasibility and efficacy of directional atherectomy in the treatment of iliac stent stenosis or occlusion and to evaluate the histologic composition of excised atherectomy specimens. METHODS: Directional atherectomy of six occluded and 10 severely stenosed iliac stents was undertaken in 12 patients at a mean interval of 28 months (range 3-69 months) after stent insertion for occlusive aortoiliac disease. In cases of stent occlusion, atherectomy was preceded by low-dose thrombolysis. In all patients stent clearance with return of femoral pulses was achieved within 24 hr and there were no significant complications. All excised specimens were sent for histologic examination. RESULTS: Eleven patients (92%) remain symptom free with unlimited walking distance at a mean follow-up interval of 11.5 months (range 3-31 months) after treatment. Histologic examination revealed typical myointimal hyperplasia at three excision sites, intimal fibrosis at three sites, atheroma at four sites and organized thrombus at six sites. CONCLUSION: Atherectomy offers an effective treatment in iliac stent occlusion and restenosis with no significant adverse effects. Debulking of these lesions seems to offer a more logical approach than simple balloon angioplasty. Clinical and duplex follow-up confirms satisfactory outcome within the first year but longer-term results are not yet known. The histologic data obtained demonstrate that stent restenosis and occlusion are likely to be multifactorial, and challenge the assumption that myointimal hyperplasia is the sole cause of iliac stent occlusion.

Comparison of Iotrolan 320 and Iohexol 350 in cardiac angiography: a randomised double-blind clinical study.

OBJECTIVE: A double-blind randomised study was conducted in two British centres, to evaluate the safety, tolerance and efficacy of the new dimeric non-ionic contrast medium Iotrolan 320 in comparison with the monomeric non-ionic compound Iohexol 350 in coronary angiography. METHODS AND MATERIAL: 120 patients were randomised to receive either Iotrolan at a concentration of 320 mgI/ml or Iohexol at a concentration of 350 mgI/ml, during selective coronary angiography and left ventriculography. The variables measured were: maximum increase of the left ventricular end-diastolic pressure up to 6 min after ventriculography, haemodynamic and electrocardiographic variables, arrhythmogenicity, clinical laboratory parameters, tolerance, adverse events and efficacy. RESULTS: Iotrolan resulted in a smaller change of left ventricular end-diastolic pressure compared to Iohexol, but the difference was not statistically significant. Transient changes in left ventricular systolic pressure, intra-arterial systolic pressure, intra-arterial diastolic pressure, and in electrocardiographic parameters, occurred after the injections, but they were not clinically significant. Changes in the clinical laboratory markers from baseline values were comparable between the two groups and confirmed good renal and hepatic tolerance. During the left ventriculogram, Iotrolan resulted in less symptoms compared to Iohexol (P = 0.002). Adverse events, which were mild or moderate in most cases, were observed with no statistical difference between the two agents. The contrast quality of both agents was good with no statistical difference. CONCLUSION: This study did not show a significant difference between Iotrolan 320 and Iohexol 350 with regard to cardiovascular safety or patient tolerance, except for a minor difference in the intensity of heat/warmth sensation.

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.

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.

Pictorial review: endovascular repair of abdominal aortic aneurysms.

Endovascular repair of abdominal aortic aneurysms is an exciting new procedure. Depending on aneurysm morphology, tube grafts, bifurcated grafts or aorto-uni-iliac systems may be used. Early results are encouraging but many problems will require solving before the technique comes into general use.

Balloon or bougie for dilatation of benign esophageal stricture?

Ninety-three adult patients with benign esophageal stricture were randomized to receive balloon or bougie dilatation. Eighty-five patients were eligible for analysis and were followed prospectively for a year. Twenty-four patients required repeat dilatation within a year, but 50 patients completed a year's follow-up without further dilatation. The bougie group initially had a better symptomatic result, experiencing significantly less dysphagia at five months, although this difference had disappeared at one year. Eighteen patients in the balloon group required redilatation for symptoms compared with six in the bougie group. The bougie group had a significantly greater increase in their stricture diameter, and this was still present at one year after dilatation. There was no significant difference in safety or patient acceptability. Balloons are probably more costly to use than bougies. Bougie dilatation is to be preferred to balloon dilatation in adults except in special circumstances.

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.

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.

Balloon angioplasty of adult aortic coarctation.

OBJECTIVE: To examine the use of balloon angioplasty in the treatment of native adult aortic coarctation. DESIGN: Haemodynamic and angiographic studies to establish the diagnosis of aortic coarctation were established before carrying out the procedure in all patients. SETTING: All the studies and angiographic procedures were performed in a large district general hospital within the departments of cardiology and radiology. There was careful perioperative monitoring. The mean hospital stay was three days. PATIENTS: 15 adult patients (with clinical, haemodynamic, and angiographic evidence of native aortic coarctation) were considered for this treatment. 13 were offered balloon angioplasty. One was excluded, as there was no significant gradient across the lesion. One patient had complete atresia at the site of the coarctation. INTERVENTIONS: Percutaneous transluminal balloon angioplasty was carried out with balloon catheters diameter 2 mm less than the diameter of the aorta immediately below the left subclavian artery to minimise the possibility of tearing the aortic wall. MAIN OUTCOME MEASURES: Abolition or significant reduction of the preoperative gradient was achieved in all 13 patients treated. Reduction in blood pressure of the upper limb was also achieved in all of the patients. Only four patients required continued antihypertensive treatment. Two patients developed false aneurysms after the procedure and required surgery. No deaths occurred. These results compare favourably with conventional surgery and are much more economical. CONCLUSIONS: Balloon angioplasty could become the first line treatment for all patients with native adult aortic coarctation, but longer term follow up is required to validate this.

Comparison of iopromide and iopamidol in left ventricular angiography and in coronary angiography.

A double blind randomized trial of two non-ionic contrast media--iopamidol and iopromide--was performed on 101 patients undergoing left ventriculography and coronary angiography. Both products performed well in the trial and there were no statistically significant differences in side effects, cardiovascular parameters, blood analysis or film quality between the two products.

Outpatient arteriography--a safe and practical proposition?

Ninety-five patients, who underwent fine catheter peripheral angiography as outpatients, were followed up and assessed to determine the safety of this procedure. No patients reported any major side effects and in particular no patients experienced a rebleed from the arterial puncture site. This procedure could be safely adopted in any radiology department.