Balloon angioplasty with intraluminal stenting as the initial treatment modality in aorto-iliac occlusive disease

The challenges of treating peripheral arterial disease

Today, peripheral arterial disease (PAD) patients need effective medical care for an extended period of their lifetime. Therefore, different treatment modalities have to be tied sequentially into an effective therapeutic chain. First, preventive measures have to be reinforced and risk factors tightly controlled. Furthermore, antiplatelet agents have to be applied in every PAD patient to reduce the risk of cardiac and cerebral ischemic events, restenosis or reocclusion after revascularization, and possibly also progression of the PAD itself. Angiotensin-converting enzyme (ACE) inhibitors should be entertained in high-risk groups such as PAD patients with diabetes. In the claudicant, exercise therapy should be strongly encouraged and vasoactive drugs considered for those who are not good candidates for either exercise training or revascularization. In patients with disabling claudication or critical limb ischemia, revascularization procedures are highly effective. Especially for high-grade stenoses or short arterial occlusions, percutaneous transluminal angioplasty (PTA) should be the method of fi rst choice followed by the best surgical procedure later on. To achieve good long-term effi cacy, a close follow-up including objective tests of both the arterial lesion and hemodynamic status, surveillance of secondary preventive measures and risk factor control is mandatory.

The TransAtlantic InterSociety Consensus (TASC) Classification System in Iliac Arterial Stent Placement: Long-term Patency and Clinical Limitations

PURPOSE

To evaluate the long-term patency of iliac arterial stent placement according to individual TransAtlantic Intersociety Consensus (TASC) stages and demonstrate the limitations of TASC classification for iliac arterial disease.

MATERIALS AND METHODS

Retrospective analysis of 218 patients who underwent iliac arterial stent placement revealed 295 stents were placed in 260 limbs. Iliac lesions of patients were classified according to the TASC classification on initial angiography but patients having bilateral different staged lesion were classified with limb based TASC classification. Analysis was performed based on the number of treated limbs not on the number of patients. Stent patency of individual TASC stages was analyzed by Kaplan-Meier methods and were compared by the log rank test.

RESULTS

The technical success rate was 99%. 171 patients (80%) were classified under a single TASC category, however, 44 patients (20%) with bilateral iliac lesions could not be classified under a single TASC stage. The number of patients and limbs in each TASC group was: TASC A (88/97), TASC B (91/97), TASC C (32/48), and TASC D (16/18). The 1, 3 and 5 year primary patencies of the iliac arterial stent for TASC A were 96%, 84%, and 81%; TASC B were 95%, 85%, and 85%; TASC C were 94%, 94%, and 78%; and TASC D were 93%, 74%, and 74%, respectively. Four TASC groups were not statistically different for primary patency rates (P < .03).

CONCLUSION

The patency of iliac arterial stents did not show statistically significant difference among TASC stages. TASC system is limited for patient classification with bilateral iliac arterial disease [corrected]

Controlled blunt microdissection for percutaneous recanalization of lower limb arterial chronic total occlusions: A single center experience

BACKGROUND

Percutaneous techniques for the revascularization of symptomatic lower limb arterial chronic total occlusions (CTOs) remain suboptimal due to difficulty in safely and reliably crossing these heavily calcified lesions using standard guidewire and balloon technology.

OBJECTIVES

The objective of this prospective study was to evaluate the technical success and safety of controlled blunt microdissection (CMD) for the treatment of resistant peripheral CTOs.

METHODS

This series enrolled 36 patients (26 men; mean age 67 +/- 12 years), with 44 symptomatic CTOs (2 terminal aortic, 24 iliac, 16 femoral, and 2 popliteal), which had previously failed conventional percutaneous revascularization. CMD was carried out using a specialized prototype catheter. Actuation of the hinged jaws of this CMD catheter created a channel within the occluded arterial segment for guidewire passage, and subsequent angioplasty and stenting using standard procedures. The problem of subintimal CMD catheter passage, creating an eccentric channel, was addressed using a second novel device, the true-lumen reentry (LRE) catheter, which allowed reentry into the downstream lumen.

RESULTS

Procedural success, evaluated angiographically, was achieved in 40 (91%) of the 44 CTOs. Fourteen (35%) of these 40 successful recanalizations required guidewire redirection, using the LRE catheter for lesion traversal. There were no complications related to CMD per se; although one patient experienced acute in-stent thrombosis, managed successfully with intra-arterial thrombolysis.

CONCLUSIONS

We therefore conclude that CMD can be used safely and successfully to facilitate recanalization of resistant CTOs in the pelvic and lower limb arteries.

Atherosclerotic Renal Artery Stenosis

The clinical diagnosis of renal artery stenosis relies on a high index of suspicion and confirmation by noninvasive imaging modalities. There are three distinct clinical syndromes associated with renal artery stenosis: renin-dependent hypertension, essential hypertension, and ischemic nephropathy. Clinical features that should heighten suspicion for renal artery stenosis include abrupt-onset or accelerated hypertension at any age, unexplained acute or chronic azotemia, azotemia induced by angiotensin-converting enzyme (ACE) inhibitors, asymmetric renal dimensions, and congestive heart failure with normal ventricular function. Patients with true renin-dependent (renovascular) hypertension are typically young or middle-age women with renal fibromuscular dysplasia (FMD). Initial therapy for renovascular hypertension associated with FMD is an ACE inhibitor; refractory hypertension responds readily to balloon angioplasty without stenting. Elderly patients with generalized atherosclerosis and hypertension often have atherosclerotic renal artery stenosis (ARAS); hypertension in these patients is usually not renin dependent (ie, essential hypertension). Hypertension alone, even if treated with multiple medications, is not a compelling indication for renal artery revascularization; these patients should be treated aggressively with antihypertensive medical therapy. Renal artery revascularization with stenting may be considered for refractory severe hypertension, and would be expected to improve blood control and modestly reduce medication requirements. Renal revascularization rarely cures hypertension in patients with ARAS. Patients with ARAS, hypertension, and end-organ injury should be considered for renal revascularization. Manifestations of end-organ injury include nonischemic pulmonary edema; hypertensive crisis associated with acute coronary syndrome, aortic dissection, or neurologic impairment; and renal insufficiency. Ischemic nephropathy is best treated before the development of advanced renal failure. The best candidates for revascularization are those with baseline serum creatinine less than 2.0 mg/dL, bilateral renal artery stenosis, normal renal resistive indices, no proteinuria, and one or more manifestations of end-organ injury. In these patients, renal revascularization is best accomplished by stenting, although surgical revascularization may be considered in patients with concomitant severe aortic aneurysmal or occlusive disease.

Intravascular ultrasound scanning improves long-term patency of iliac lesions treated with balloon angioplasty and primary stenting

PURPOSE

Underdeployment of an intravascular stent has been identified as a cause of restenosis or occlusion of a treated arterial lesion. Intravascular ultrasound (IVUS) has been shown to initially improve the anatomic and clinical stenting. The purpose of this study was to determine whether the use of IVUS increased long-term patency of this intervention.

METHODS

Between March 1992 and October 1995, 71 limbs (52 patients) with symptomatic aortoiliac occlusive disease underwent balloon angioplasty with primary stenting. IVUS and arteriography were used in 49 limbs (36 patients) to evaluate stent deployment. Arteriography alone was used in 22 limbs (16 patients) to evaluate stent deployment. Patients were captured prospectively in a vascular registry and retrospectively reviewed.

RESULTS

Mean age of patients treated with IVUS was 61.1 plus minus 9.0 years (range, 38-85) versus 70.0 plus minus 10.1 years (range, 57-87) in patients treated without IVUS (P <.01). There was no difference between the groups with respect to preoperative comorbidities, ankle-brachial indices, or number of stents per limb. Mean follow-up for IVUS patients was 62.1 plus minus 7.3 months (range, 15-81) and 57.9 plus minus 8.7 months (range, 8-80) for patients treated without IVUS (P = not significant). In 40% (20/49) of limbs, IVUS demonstrated inadequate stent deployment at the time of the original procedure. Kaplan-Meier 3- and 6-year primary patency estimates were 100% and 100% in the IVUS group and 82% and 69%, respectively, in limbs treated without IVUS (P <.001). There have been no secondary procedures performed in limbs treated with IVUS and a 23% (5/22) secondary intervention rate in the non-IVUS group (P <.05). Overall Kaplan-Meier survival estimates at 3 and 6 years for all patients were 84% and 67%, respectively.

CONCLUSION

Balloon angioplasty and primary stenting of symptomatic aortoiliac occlusive lesions is a durable treatment option. Long-term follow-up of treated patients shows outcomes that are comparable with direct surgical intervention. IVUS significantly improved the long-term patency of iliac arterial lesions treated with balloon angioplasty and stenting by defining the appropriate angioplasty diameter endpoint and adequacy of stent deployment.

Intra-aortic balloon pump placement following aorto-iliac angioplasty and stent placement

Approximately 20% of patients are unable to receive an intra-aortic balloon pump (IABP) due to aorto-iliac atherosclerotic disease. Aorto-iliac stenoses can be managed with angioplasty or stent placement; however, there are limited data about this strategy to facilitate IABP placement. Thirty-seven IABPs were placed in 35 patients. A total of 45 revascularization procedures were performed. With revascularization, the minimal lumen diameter increased from 2.78 +/- 1.46 to 6.75 +/- 2.36 mm (P < 0.0001). Limb ischemia occurred following 2/37 (5%) IABP insertions. Limb ischemia was managed with IABP removal and angioplasty. The mortality rate was 32%. Mortality was more common with chronic renal insufficiency (8/11, 73%; P = 0.0014), dialysis-dependent renal failure (3/3, 100%; P = 0.028), and presentation with acute myocardial infarction (8/15 patients, 53%; P = 0.036). Although no patients required vascular surgery for limb ischemia, one patient required surgery for bleeding. Angioplasty or stenting to facilitate IABP placement in patients with peripheral vascular disease is safe and effective.

Endovascular treatment of occlusive lesions in the distal aorta: mid-term results in a series of 31 consecutive patients

The purpose of this study was to evaluate the early and mid-term results of endovascular treatment of occlusive lesions in the distal aorta in a consecutive series of patients. Between February 1996 and March 1999, a total of 31 patients underwent transluminal procedures for treatment of occlusive atherosclerotic lesions located at the lower end of the aorta. Thirty patients presented with intermittent claudication and one had critical ischemia. Manifestations were bilateral in 26 cases and unilateral in 5. The lesion was confined to the lower aorta in 3 patients and extended to the common iliac arteries in 19, with predominant proximal lesions of the common iliac artery occurring in 9 patients. Fourteen patients had concurrent infracrural occlusive lesions. All patients underwent exclusive endovascular treatment without any associated open surgical procedure. The three patients with isolated aortic lesions were treated by angioplasty, followed by stent placement in two cases. The 19 patients with aortobiiliac lesions were treated by bilateral common iliac artery angioplasty according to the "kissing-balloon" technique; 7 of these patients also underwent aortic angioplasty. In these 19 patients, aortic stenting was performed in 3 cases and bilateral iliac stenting in 10 cases, including 3 in association with aortic stenting. The nine patients with a proximal lesion of the common iliac arteries were treated by angioplasty, followed by bilateral stenting in three cases and unilateral stenting in three cases. The findings of this study show that the mid-term anatomical and functional results of endovascular treatment for atherosclerotic lesions of the distal aorta are satisfactory. We recommend it as the initial treatment modality.

Iliac occlusions: stenting or crossover grafting? An examination of patency and cost

OBJECTIVES

Percutaneous transluminal angioplasty with stenting is perceived to be a less invasive and cheaper option for the treatment of iliac artery occlusion than surgical reconstruction. We have carried out a prospective observational study of all patients undergoing an iliac stent or femorofemoral crossover graft for iliac artery occlusion to assess the cost effectiveness of the two approaches in a district general hospital.

METHODS

Fifty-one patients underwent primary angioplasty with stenting and 87 patients crossover grafting. Patients were all assessed 2 months after their procedure and then at intervals over the following years.

RESULTS

In 13 cases, it was impossible to place the stent successfully. In a further 10 patients, major complications occurred which were mainly thromboembolic. Fifteen patients underwent crossover grafting after failure to insert a stent, or after stent occlusion. No major complications occurred following crossover grafting. The median length of stay following successful stenting was 1 day; the following crossover grafting was 4 days. The mean stay was higher in each group (2.5 and 5.8 days) and is a more accurate parameter for estimation of cost, which for iliac stenting is estimated at pound1912 versus pound3072 for crossover grafting. The mean additional cost of those patients sustaining complications after stenting was pound2481. On an <<<<intention to treat>>>> basis, patency following stent insertion at 6 months was 52%; patency after bypass was 100% (p <0.0001). If any complication occurs after stenting, the cost advantage of the procedure is lost. In those patients without complication, the initial cost benefit of iliac stenting is lost within 6 months, as patients require further intervention, usually as a crossover graft, when the stent occludes. Crossover grafting is a durable low-risk procedure.

CONCLUSIONS

We suggest that stenting of occluded iliac arteries should be reserved for those patients with limited life expectancy. Patients who are younger and fitter should be offered femorofemoral crossover grafting as a primary procedure until research enables identification of those patients who are most likely to maintain long-term patency after stenting.

Accidental intraaortic placement of a Greenfield filter

A Greenfield vena cava filter was accidentally placed in the mid-abdominal aorta. It was manipulated to the aortic bifurcation, where it has been observed for >48 months. This case is the first example of arterial placement of a vena cava filter. This report describes the probable mechanisms for this aberrant placement, methods for prevention of this complication, and options for management of this problem.

Aortoiliac stenting, determinants of clinical outcome

OBJECTIVES

To determine predictors of clinical outcome in stenting aortoiliac disease.

DESIGN

Prospective/retrospective study.

MATERIALS AND METHODS

One hundred and forty patients (163 limbs) underwent iliac artery stenting in the period 1994-1997. Ninety-eight occlusions and 65 stenoses were treated, either with primary stenting (n = 129) or after failed angioplasty (n = 34). Median follow-up 18 months (1-66). Factors analysed for their effect on outcome were: gender, age, Fontaine stage, ABI, lesion type/length/site, primary or secondary stenting, stent type, BP, smoking, diabetes, aspirin, cholesterol, residual gradient, overhanging and run-off.

RESULTS

The immediate success was 95%. The primary successful clinical outcome was 90% at 12 months and 84% at 36 months; the primary-assisted successful clinical outcome was 95% at 12 months and 91% at 36 months and the secondary successful clinical outcome was 92% at 12 months and 87% at 36 months. Adverse factors affecting outcome were: residual pressure gradient (> 10 mmHg) and no treatment with aspirin (p < 0.05). Major complications occurred in 18% of patients with a re-intervention in 8%. The 30-day mortality was 5.5%.

CONCLUSIONS

Stenting for aortoiliac occlusive disease has good short and long term clinical success, with low morbidity and mortality. Factors that might improve results further are ensuring that patients are taking aspirin and any residual pressure gradient is abolished.

Aortic bifurcation reconstruction: use of the Memotherm self-expanding nitinol stent for stenoses and occlusions

PURPOSE

To assess the technical success, initial clinical outcome, and intermediate follow-up of the Memotherm nitinol self-expanding stent in aortic bifurcation reconstruction.

METHODS

Thirty-three patients (13 male, 20 female), mean age 64 years, were treated, who had symptoms classified by the Surgical Vascular Society/International Society of Cardiovascular Surgery (SVS/ICVS) classification as grade 2 in 11 (33%), grade 3 in 19 (58%) and grade 4 in 3 (9%) patients. Lesions were classified according to severity and type. Indications for placement of a Memotherm nitinol self-expanding stent were failed angioplasty in 14 (42%), chronic occlusions in 12 (37%), and complex stenoses in seven (21%) patients.

RESULTS

Sixty-seven stents were technically successfully placed in 66 aorto-iliac segments in 33 patients, with one major complication. Initial clinical outcome was improvement in 25 (81%), no change in four (13%), and a worsening in two (6%) patients by Rutherford criteria. Mean early ankle/brachial pressure index (ABI) gain was 0. 27 for occlusions and 0.05 for stenoses. Clinical follow-up was obtained in all patients, with retrospective angiographic follow-up in 28 (85%) at a mean of 16 months (range 12-26 months). The decrease in ABI and the decrease in angiographic luminal diameter at follow-up was determined as the "late loss." The mean ABI late losses were -0.06, 0.00, and 0.09, and the mean angiographic late losses were 6.7%, 10% and 14% for occlusions, stenoses, and normal segments respectively. Primary clinical patency was 96%, primary angiographic patency was 89%, and secondary angiographic patency was 93%.

CONCLUSION

The high technical success of stent placement, the low complication rates for aortic bifurcation reconstruction using the Memotherm self-expanding stent, and high clinical and angiographic patency maintained at intermediate follow-up support their use in aortic bifurcation reconstruction.

Carotid angioplasty and stenting in high-risk patients

BACKGROUND

To examine our initial experience in carotid stenting (CS) for the prevention of stroke in patients with high-grade carotid stenoses.

METHODS

The authors performed 26 CS procedures in 25 carotid vessels in 22 patients over a 15-month period. All carotid stenoses treated, except one, were 70% or greater. Of all CS procedures, 84% were performed for obstructing atherosclerotic plaques. CS was performed in one patient each for carotid dissection and pseudoaneurysms caused by a gunshot wound, post-radiation stenosis, post-carotid endarterectomy (CEA) restenosis, and a flow-obstructing post-CEA intimal flap. Of all patients, 68.2% were symptomatic, with a history of stroke or transient ischemic attacks ipsilateral to the treated carotid artery. In addition, 36.4% of our patients were either hospitalized or required skilled nursing care before CS because of severe neurologic deficits. Using the Sundt CEA-risk classification system, 59.1% of our patients were classified as Grade III and 40.9% were Grade IV pre-CS. All but one patient had either a compelling medical or anatomic reason for endovascular treatment of their carotid disease. We used both Wallstents and Palmaz stents, and all procedures were performed via the transfemoral route. Three procedures were performed in conjunction with detachable platinum coil embolization for multiple carotid pseudoaneurysms, a residual carotid "stump" after previous ICA thrombosis, and an ipsilateral MCA saccular aneurysm.

RESULTS

We had a 96.2% procedural technical success rate. There was one death in our series 3 weeks post-CS attributable to myocardial infarction. Despite a high 30-day combined death, stroke, and ipsilateral blindness rate of 27.3% (6/22 patients), only two ipsilateral strokes directly related to CS occurred (7.7% per procedures performed) from which one patient recovered fully within 5 days. The average follow-up post-CS was 5.9 months (range, 3 weeks-15 months). Of successfully treated vessels, 58.3% have undergone 6-month follow-up vascular imaging, which has revealed a 14.3% rate of occlusion or restenosis greater than 50%. At or beyond 1 month post-CS, 19 of 21 surviving patients (90.5%) were ambulatory, fluent of speech, and independent, and none has thus far suffered a delayed stroke or TIA.

CONCLUSION

CS seems to be a reasonable alternative to medical management for the treatment of carotid disease in patients deemed to be poor candidates for standard carotid surgery. Longer term follow-up is necessary to assess the durability of carotid revascularization using CS.

Does stent placement improve the results of ineffective or complicated iliac artery angioplasty?

OBJECTIVE

This study was undertaken to determine the results and complications of stents placed for initially unsuccessful or complicated iliac percutaneous transluminal angioplasty (PTA), the effect of location (external iliac or common iliac) on outcome, and the influence of superficial femoral artery patency on benefit.

DESIGN

From 1992 through 1997, 350 patients underwent iliac artery PTA at the authors' institutions. Of this group, 88 patients (88 arteries) had one or more stents placed after PTA (140 stents in total) for residual stenosis or pressure gradient (63 patients), iliac dissection (12 patients), long-segment occlusion (10 patients), or recurrent stenosis (3 patients). Thirty patients required the placement of more than one stent. The indications for PTA in these 88 patients were claudication (48 patients) and limb-threatening ischemia (40 patients). Forty-seven patients had stents placed in the common iliac, 29 patients had stents placed in the external iliac, and 12 patients had stents placed in both. Seventy-one arteries (81%) were stenotic, and 17 (19%) were occluded before PTA. Sixty-six arteries were treated by interventional radiologists, 15 by a vascular surgeon, and 7 jointly.

MAIN OUTCOME MEASURE

Criteria for success included (1) increase of at least one clinical category of chronic limb ischemia from baseline or satisfactory wound healing, (2) maintenance of an ankle/brachial index increase of more than 0.10 above the preprocedure index, and (3) residual angiographic stenosis less than 25% and, for patients with pressure gradient measurements, a residual gradient less than 10 mm Hg.

RESULTS

Stent placement was accomplished in all 88 patients with 16 (18%) major complications. Mean follow-up was 17 months (range, 3 to 48 months). By life-table analysis, success was 75% at 1 year, 62% at 2 years, and 57% at 3 years. No cardiovascular risk factor or independent variable was statistically significant in predicting success. There was no difference in success rates for common iliac or external iliac lesions. Superficial femoral artery patency did not correlate with outcome.

CONCLUSIONS

Although stents can eliminate residual lesions and arterial dissection, these patients are likely to require adjuvant or subsequent procedures to attain clinical success. By controlling the PTA complication and treating the emergent problem, stents may allow for subsequent elective intervention.

Aortoiliac stent placement in patients treated for intermittent claudication

PURPOSE

To assess the results of iliac artery stent placement for the treatment of patients with intermittent claudication.

MATERIALS AND METHODS

Lesions in 90 iliac arteries were treated in 65 patients with 111 Wallstents and 21 Palmaz stents. Stents were placed for symptoms of intermittent claudication classified as grade I, categories 1-3 by the SVS/ISCVS/SCVIR reporting standards. Sixty-two stenosed arteries and 28 chronically occluded arteries were treated. Patients were followed for up to 57.1 months (mean, 17.4 months +/- 14.9).

RESULTS

Technical success was achieved in 87 of 90 iliac limbs (97%), with major complications in seven of 65 patients (11%). The 30-day mortality was zero. Mean pressure gradients across stenoses improved from 14.7 mm Hg +/- 9.8 to 1.4 mm Hg +/- 1.4 (P < .001). Ankle-brachial indices improved from 0.62 +/- 0.21 to 0.90 +/- 0.18 (P < .001). With use of the Rutherford criteria, 84% demonstrated +2 or +3 improvement. The cumulative patency rates were 77%, 71%, 62%, and 62% at 1, 2, 3, and 4 years (standard error [SE] < 10%). Continued clinical and noninvasive test benefit was present in 80%, 80%, 73%, and 73% at 1, 2, 3, and 4 years, respectively (SE < 10%).

CONCLUSIONS

Significant hemodynamic improvement can be achieved by percutaneous stent placement, with excellent clinical results. Observed mortality in this series was zero, but major complications, requiring modification of the treatment plan, were seen in 11% of patients. Clinical results were better than suggested using current accepting reporting standards for "patency."

Intraoperative endovascular angioplasty and stenting of iliac artery: an adjunct to femoro-popliteal bypass

BACKGROUND

With the rapid development of endovascular techniques, the management strategy of patients with multilevel atherosclerotic arterial occlusive disease is also evolving. Iliac artery stenting is a means whereby multiple bypass operations can be avoided in such patients. The early results of preoperative iliac artery stenting seem promising but the role of intraoperative iliac artery angioplasty and stenting is less clear.

STUDY DESIGN

This study was undertaken to evaluate our early results of a combined endovascular and operative approach to patients with multilevel atherosclerotic arterial occlusive disease. Between June 1995 and March 1997, primary intraoperative iliac artery balloon angioplasty and stent placement were performed on 13 affected limbs of 12 patients undergoing an infrainguinal bypass operation. Indications for operation, patient demographics, and risk factors were noted. The outcome of surgery and the patency rates of bypass graft and stent were also recorded.

RESULTS

The initial technical success of primary iliac artery angioplasty and stenting was 93%. An improvement of the ankle-brachial index by a mean value of 0.38 was attained after operation (p < 0.001). Clinical success, based on the criteria suggested by the Society for Vascular Surgery/International Society for Cardiovascular Surgery, was achieved in all patients. There was no operative or hospital mortality. Postoperative morbidity rate was 8% (n = 1). The cumulative 1-year patency rates of iliac stent and infra-inguinal bypass grafts were 100% and 85%, respectively. The limb loss rate was 7%.

CONCLUSIONS

The technique of intraoperative angioplasty and stenting can be easily mastered by an experienced and skilled vascular surgeon, using a portable C-arm fluoroscopic unit, in the operation theater. A combined endovascular and operative approach optimizes the therapeutic option to this selected group of patients.

Use of intravascular ultrasound improves long-term clinical outcome in the endovascular management of atherosclerotic aortoiliac occlusive disease

PURPOSE

This study was undertaken to determine whether the use of intravascular ultrasound (IVUS) during balloon angioplasty and stenting of atherosclerotic aortoiliac occlusive lesions improved long-term clinical outcome. IVUS has been previously shown to be more accurate than arteriography in evaluating the deployment of stents in both peripheral and coronary arteries. Incomplete stent deployment has been anecdotally identified as a cause of restenosis or occlusion of a treated lesion. To our knowledge, there have been no previous studies that demonstrate whether the use of IVUS will affect the long-term patency rate of stented arterial lesions.

METHODS

Between March 1992 and October 1995, 52 patients with symptomatic aortoiliac occlusive disease underwent balloon angioplasty and stenting of their lesions. We retrospectively reviewed these cases to determine whether the use of IVUS influenced the long-term patency rate of these interventions. Follow-up ranged from 1 to 4 years with a mean of 28 months.

RESULTS

Fifty-two patients had confirmation of adequate stent deployment by arteriography. IVUS was used in conjunction with arteriography in 36 patients to evaluate stent deployment. Patients in the IVUS-assisted group were slightly younger than those patients who were evaluated solely by arteriography (p < 0.01). No statistical differences were noted between the two groups with respect to coronary artery disease, diabetes mellitus, obstructive pulmonary disease, hypertension, or obesity. Length of hospital stay, number of stents used, and preoperative ankle brachial indexes were comparable in both groups. In the arteriography plus IVUS group, 40% of patients had underdeployed stents by IVUS evaluation, though they appeared adequately expanded by arteriography. No restenoses or occlusions were seen in the arteriography plus IVUS group. Restenosis or occlusion of the stented lesion occurred in 25% of patients evaluated by arteriography alone (p < 0.01). These failures were treated by either thrombolysis or catheter thrombectomy and were then evaluated with IVUS. All were found to have underdeployed stents. Subsequent treatment consisted of adequate redeployment of existing stents using IVUS criteria. These salvaged reconstructions have continued to remain patent.

CONCLUSIONS

The use of IVUS may be the best means for assessing adequacy of arterial stent deployment. Our study suggests that the use of IVUS improves the long-term clinical outcome of balloon angioplasty and stented aortoiliac occlusive lesions.

Treatment of chronic iliac artery occlusions with guide wire recanalization and primary stent placement

PURPOSE

To evaluate the results of primary stent placement without initial thrombolysis in the treatment of iliac occlusions.

MATERIALS AND METHODS

During a 3-year period, 61 iliac artery occlusions were treated in 59 patients. The mean length of the occluded segment was 10 cm (range, 4-25 cm). The occluded arteries were treated with primary placement of self-expandable metallic stents.

RESULTS

Successful recanalization with primary stent placement was possible in 56 of 61 occlusions (92% technical success rate). Mean Doppler ankle/brachial index increased from 0.51 to 0.90 immediately after treatment and was 0.91 on the last follow-up (P < .05). Primary patency rate at 24 months was 73%, and secondary patency rate was 88%. Procedural complications included distal embolization (n = 4) and an episode of massive intra-abdominal bleeding. Three patients developed a hematoma at the puncture site that did not require additional therapy. Late complications included stent occlusion (n = 9) and significant stenosis related to intimal hyperplasia (n = 1). Mean follow-up period was 29 months (range, 7-55 months).

CONCLUSION

Primary stent placement is an effective therapeutic option for iliac artery occlusions.

Intraaortic balloon pump insertion after percutaneous revascularization in patients with severe peripheral vascular disease

Severe aortoiliac peripheral vascular disease (PVD) is considered a contraindication for the placement of an intraaortic balloon pump (IABP) because of a high risk of limb ischemia. Recent advances in percutaneous transluminal angioplasty (PTA) and stenting have altered the treatment of iliac stenoses such that the results of PTA with stenting compare favorably with surgery. We reviewed our experience with placement of IABP between July 1994 and February 1996. Of 64 patients receiving IABP, 17 had known or suspected peripheral vascular disease. Severe iliac or distal aortic stenoses were present in 9. These 9 patients underwent PTA with or without stenting prior to 10 IABP insertions. Limb ischemia occurred in 10% of PVD patients treated with percutaneous revascularization, compared to 11% in patients without PVD. No patient had a serious vascular complication or required vascular surgery. We conclude that percutaneous revascularization in patients with severe aortoiliac PVD, for whom this IABP insertion had previously been considered contraindicated, results in a low rate of limb ischemia.

Use of intravascular ultrasound in the endovascular management of atherosclerotic aortoiliac occlusive disease

BACKGROUND

Intravascular ultrasound (IVUS) has been described as interesting technology in search of a clinical application by some and by others as a valuable diagnostic tool for many endovascular interventions. Its clinical usefulness has yet to be fully defined. When used during endovascular interventions, it can provide structural and diagnostic information, assess effectiveness of the therapy, and identify treatment-related complications.

METHODS

Thirty-two consecutive patients with atherosclerotic aortoiliac occlusive disease who presented with 40 separate arterial lesions were evaluated with IVUS before and after balloon angioplasty and intraluminal stent placement. Information obtained from IVUS was compared with similar data obtained from simultaneous angiographic images. Both techniques were evaluated with respect to assessment of vessel size, lesion location, adequacy of therapy, and identification of complications.

RESULTS

Real time IVUS imaging compared with angiographic imaging showed that in 62% of the patients, vessel diameter was underassessed using angiographic criteria alone. More importantly, 40% (16 of the 40 lesions) had underdeployed stents by IVUS evaluation that appeared adequately expanded by angiographic criteria. Further stent expansion with a larger balloon was necessary to achieve accurate stent to vessel wall apposition. This was found to be significant by an exact binomial 95% confidence interval. Incomplete stent deployment has been identified as a possible cause for restenosis and vessel occlusion. Information obtained from IVUS imaging substantially altered the endovascular therapy in approximately 40% of our patients and provided valuable vessel sizing and lesion composition information in 62% of the patients.

CONCLUSION

Intravascular ultrasound can provide important diagnostic information that can alter the conduct of selected endovascular procedures. It is especially useful when the procedure requires deployment of arterial stents.

Results of peripheral endovascular procedures in the operating room

PURPOSE

This study presents the results of closed (percutaneous) and open endovascular procedures performed exclusively by vascular surgeons in the operating room and compares them with results from combined series from the literature, including primarily closed procedures in radiology or cardiology facilities.

METHODS

Retrospective review of 607 consecutive peripheral arterial and venous angioplasties, stents, thrombolytic cases, and inferior vena caval filters in 446 patients was analyzed for immediate success rate, complication rate, and 1-year life table patency rate.

RESULTS

The incidence of initial technical success was: aorta, 89%; iliac artery, 91%; superficial femoral artery, 90%; popliteal artery, 91%; tibial arteries, 79%; arm arteries and veins, 86%; renal arteries, 100%; IVC filters, 98%; and iliofemoral veins, 100%. The 1-year primary patency rates, including technical failures, were 70.3% in 113 femoropopliteal procedures and 83.7% in 194 iliac arteries. Advantages to the use of the operating room included: (1) simultaneous angioplasty during a bypass operation for abnormalities proximal or distal to the graft, (2) correction of lesions first discovered during thrombectomy, and (3) optimum patient monitoring and sedation in the operating room.

CONCLUSIONS

Endovascular procedures performed by vascular surgeons in the operating room lead to results comparable with procedures performed in nonsurgical interventional suites, and the use of the operating room has advantages.

Noncoronary vascular stenting

The aim of this report is to review the current state of the art with respect to noncoronary vascular stenting. A review of the literature was performed, examining the historical aspects of stent design and usage, as well as the currently available designs and their respective functions. When appropriate, we note our personal experience with stent placement in each anatomic site. Currently available stents take many forms: balloon-expandable, self-expanding, and shape-memory alloy. Varied design modifications have been made to maximize the open area, to limit the surface area of the prosthesis, to increase (or decrease) flexibility, and to increase (or decrease) stent plasticity and elasticity. Modifications to minimize thrombogenicity are also underway. The clinical uses of the currently available stents in multiple anatomic locations will be discussed. Intravascular stents are an addition to the arsenal available for prolonging blood vessel patency.

The use of expandable metallic airway stents for tracheobronchial obstruction in children

Expandable metallic angioplasty stents (Palmaz stent) have been implanted in the trachea and/or bronchi of seven children. Three children had severe tracheal stenosis after tracheoplasty for congenital tracheal stenosis repair, and four had tracheomalacia or bronchomalacia with or without vascular compression. The mean age at stenting was 9.7 months (range, 2 to 15 months). Balloon expandable stents were inserted into the trachea or bronchus through a 3.5-mm bronchoscope under fluoroscopic control. Initially a single tracheal stent was used for all patients except for one with obstruction in the trachea and both bronchi, in whom three stents were implanted. Three children had recurrent airway obstruction 1 month later; one was cured with a second stent; one child died 1 year later; and the other is being treated for heart disease. The others have no serious respiratory problems. The stents in all have been in place for 1 to 25 (mean, 11) months. No immediate complications were noted. Early and late bronchoscopy showed incomplete epithelialization of the stent and patches of granulation tissue on it. Two stents were removed bronchoscopically, one at the completion of treatment for tracheomalacia and the other at the time of recurrent airway obstruction. This preliminary experience indicates that expandable metallic stents have a useful role in the treatment of selected lower airway obstructions.