Association of Circulating Transforming Growth Factor beta, Tumor Necrosis Factor alpha and Basic Fibroblast Growth Factor with Restenosis after Transluminal Angioplasty

OBJECTIVES

To assess prospectively the early time course of Transforming Growth Factor beta-1 (TGFbeta-1), basic Fibroblast Growth Factor (bFGF) and Tumor Necrosis Factor alpha (TNFalpha) as possible contributors to restenosis development after angioplasty.

DESIGN

Prospective Study.

METHODS

The levels of the soluble forms of these factors in the early response to Percutaneous Transluminal Angioplasty (PTA) in the arteries of the lower limb were prospectively assessed. 32 patients with peripheral arterial occlusive disease (PAOD), presenting with intermittent claudication (Fontaine stage IIb) were scheduled for angioplasty treatment. Serum levels of TGFbeta-1, TNFalpha and bFGF were assessed before intervention, 15 and 60 minutes after, 24 hours after as well as 2 and 4 weeks after intervention. We compared the distribution patterns between patients treated with balloon angioplasty and patients who required secondary stent implantation. Endpoint was the development of restenosis within 6 months after interventional treatment, defined as a lumen diameter reduction of more than 50% by ultrasound measurement compared to the result after PTA.

RESULTS

The patients who later developed restenosis had significantly higher levels of TGFbeta-1 at 15 minutes, 24 hours and 2 weeks after PTA (p<0.05). TNFalpha and bFGF were only detected in a few patients and no significant change of serum levels was observed.

CONCLUSION

The results demonstrate a possible role of TGFbeta-1 in the formation of restenosis after PTA.

Isolated iatrogenic abdominal aortic dissection secondary to transfemoral arteriography: a case report

Primary dissections of the abdominal aorta are rare and in most cases traumatic in origin. However, the natural history of isolated iatrogenic abdominal aortic dissection has not been well defined. This report describes a case of a 69-year-old patient with iatrogenic dissection of the abdominal aorta after arteriography and delayed surgical approach.

The collateral pathway from the left internal thoracic artery to the left external iliac artery detected by multislice computed tomography

It is important to evaluate the presence or absence of the collateral pathway from the left internal thoracic artery in aortoiliac occlusive disease. This case report indicates that multislice computed tomography is a very useful method for detecting this collateral pathway.

Buttock claudication disclosing a thrombosis of the superior left gluteal artery: Report of a case diagnosed by a selective arteriography of the iliac artery, and cured by per-cutaneous stenting

We report on a case of left buttock claudication, occurring consistently after 150 meters walking, and disappearing after a short rest. As magnetic resonance angiography (MRA) did not show any explanation for this claudication, a selective angiography of left internal iliac artery was requested, which clearly identified a tight stenosis of the onset of the left superior gluteal artery. A per-cutaneous angioplasty together with stenting of this artery, induced a prompt and complete relief of pain at the three months follow-up visit.

Plaque excision with the Silverhawk catheter: Early results in patients with claudication or critical limb ischemia

OBJECTIVE

This study was conducted to detail the early experience after infrainguinal atherectomy using the Silverhawk plaque excision catheter for the treatment of symptomatic peripheral vascular disease.

METHODS

A prospective database was established in August 2004 in which data for operations, outcomes, and follow-up were recorded for patients undergoing percutaneous plaque excision for peripheral arterial occlusive disease. Society for Vascular Surgery (SVS) ischemia scores and femoropopliteal TransAtlantic Inter-Society Consensus (TASC) criteria were assigned. A follow-up protocol included duplex ultrasound surveillance at 1, 3, and 6 months and then yearly thereafter. Standard statistical analyses were performed.

RESULTS

During a 17-month period, 66 limbs of 60 patients (37 men [61.7%]) underwent 70 plaque excisions (four repeat procedures). Indications included tissue loss based on SVS ischemia at grades 5 and 6 (25/70), rest pain at grade 4 (22/70), and claudication at grades 2 to 3 (23/70). The mean lesion length was 8.8 +/- 0.7 cm. The technical success rate was 87.1% (61/70). Adjunctive treatment was required in 17 procedures (24.3%), consisting of 14 balloon angioplasties and three stents. Femoropopliteal TASC criteria included 5 TASC A lesions, 14 TASC B lesions, 32 TASC C lesions, and 19 TASC D lesions. Although 17 plaque excisions included a tibial vessel, no patient underwent isolated tibial atherectomy. The mean increase in ankle-brachial index was 0.27 +/- 0.04 and in toe pressure, 20.3 +/- 6.9 mm Hg. Mean duplex ultrasound follow-up was 5.2 months (range, 1 to 17 months). One-year primary, primary assisted, and secondary patency was 61.7%, 64.1%, and 76.4%, respectively. Restenosis or occlusion developed in 12 patients (16.7%) and was detected at a mean of 2.8 +/- 0.7 months. Restenosis or occlusion was significantly more common (P < .05) in patients with TASC C and D lesions compared with patients with TASC A and B lesions. Six (8.3%) of 12 patients underwent reintervention on the basis of duplex ultrasound surveillance results. Four (33.3%) of 12 patients experienced reocclusion during the same hospitalization, and amputation and open revascularization were required in two patients each.

CONCLUSIONS

Percutaneous plaque excision is a viable treatment option for lower extremity revascularization. Outcomes are related to ischemia and lesion severity. Patency and limb salvage rates are equivalent to other endovascular modalities.

CT Angiography of Peripheral Arterial Occlusive Disease

Lower extremity computed tomography angiography (CTA) is an effective, noninvasive, and robust imaging modality that is being used increasingly to evaluate patients with peripheral arterial occlusive disease (PAOD). It is important for vascular and interventional radiologists, and vascular surgeons to be familiar with the strengths and limitations, diagnostic accuracy, and practical application of lower extremity CTA. In this article, we review the technical principles of image acquisition, visualization techniques to effectively interpret the large volumetric datasets generated, and the current practical application of lower extremity CTA with respect to PAOD.

Chronic Ergot Toxicity Presenting with Bilateral External Iliac Artery Dissection and Lower Extremity Rest Pain

Chronic use of ergot alkaloids has been recognized as a rare cause of lower extremity ischemia. Most patients with ergot toxicity present with symptoms of lower extremity claudication. Herein we present a woman with bilateral lower extremity rest pain and a history of chronic ergot use for migraine headaches. Arteriography demonstrated extensive pruning of the distal arterial tree along with bilateral external iliac artery dissections - a finding that is not often associated with young, normotensive patients with chronic ergot toxicity. This patient was treated with endovascular stenting of the dissections along with cessation of ergot. Her symptoms improved markedly, and follow-up arteriography 6 weeks later demonstrated resolution of the iliac dissections along with restoration of nearly normal lower extremity runoff vessels. Discontinuation of ergot-containing products and cessation of tobacco and caffeine use is the cornerstone of therapy in chronic ergot toxicity. The association of ergot toxicity and iliac dissection has not been previously described. Endovascular or surgical interventions may be considered in patients with ergot toxicity for specific indications or those whose symptoms progress despite conservative management.

Popliteal artery entrapment syndrome: morphological classification utilizing MR imaging

OBJECTIVE

To retrospectively analyze magnetic resonance (MR) findings in patients with popliteal arterial entrapment syndrome.

MATERIALS AND METHODS

This study was a retrospective MRI and CT scan review of 12 patients with 23 limbs with popliteal artery entrapment syndrome (PAES) treated over a 10-yr period. All 12 patients (23 limbs) were evaluated with MR and CT scan (11 patients - bilateral sides; one patient - unilateral side). All cases were classified as to various types of anomalous relationships between the popliteal artery and the neighboring muscles. The PAES was classified to gastrocnemius medial head and lateral head anomaly. Gastrocnemius medial head anomaly was classified according to the classification made by Whelan and Rich, from type 1 to type 6 [12, 13]. Gastrocnemius lateral head anomaly was defined as popliteal artery entrapment due to medially inserted gastrocnemius lateral head or aberrant accessory head of gastrocnemius lateral head.

RESULTS

The gastrocnemius medial head anomaly was found in 14 limbs (14/23). The classic type 1 was found in none, type 2 in five patients (six limbs), type 3 in four patients (five limbs), type 4 in none, type 5 in one patient (one limb) and type 6 in one patient (two limbs). The uncommon type, i.e. lateral head of gastrocnemius anomaly, was found in five patients (eight limbs).

CONCLUSION

The gastrocnemius medial head anomaly was the cause of PAES, and PAES was classified by medial head anomaly. However the gastrocnemius lateral head anomaly was also the cause of PAES, and most cases of gastrocnemius lateral head anomaliy showed aberrant accessory slip which entrapped the popliteal artery and vein.

Infrainguinal revascularization based on duplex ultrasound arterial mapping

AIM

Recent reports have advocated duplex ultrasound arterial mapping (DUAM) as the sole preoperative imaging modality for planning infrainguinal revascularization. This study reports the outcome of arterial revascularization procedures for chronic limb ischemia based on DUAM.

METHODS

From January 2002 to December 2004, 253 patients (175 men, 78 women) underwent infrainguinal revascularization based on DUAM. The indications for surgery were severe claudication (11%), rest pain (15%), gangrene (40%), non-healing ulcer (34%). Preoperative evaluation consisted of DUAM alone in 208 cases (82%) or a combination of DUAM and contrast arteriography (CA) in 30 (12%) and intraoperative angiography or direct exploration in 15 (6%). DUAM allowed imaging from the distal aorta to the pedal arteries and the selection of inflow and outflow bypass anastomosis sites. CA was deemed necessary due to technical difficulties or medico-legal reasons.

RESULTS

DUAM procedure time averaged 90+30 min. Proximal anastomosis was located in common femoral arteries in 202 cases, popliteal in 51. Distal anastomosis was to the tibial arteries in 144 cases and pedal arteries in 109. Primary patency was 89% and 67% at 12 and 36 months. Secondary patency was 93% and 82% at 12 and 36 months.

CONCLUSIONS

This experience shows that DUAM may be a safe alternative to CA for patients with chronic limb ischemia. Adequate training and experience is necessary to utilize this technique as the sole preoperative imaging modality for planning infrainguinal revascularization.

Persistent sciatic artery: an uncommon cause of intermittent claudication

Persistent sciatic artery (PSA) is a rarely seen variation of the lower limb vessels. Anatomically the PSA is the continuation of internal iliac arteries. It follows the sciatic nerve from the sciatic foramen to the level of the knee. We report our experience with conservative therapy in a patient with complete occlusion of a PSA. A 54-year-old man with typical symptoms of intermittent claudication on the left limb was referred to our Department. After clinical examination Doppler and duplex sonography were performed. Angiography showed bilateral PSA. On the left side the PSA was occluded. The patient received 20 intravenous courses of prostaglandin E1 for 4 weeks, followed by oral anticoagulation with phenprocoumon for life (INR: 2.5-3.5). After 3 years therapy he does not show any typical symptoms of intermittent claudication or limb ischemia. This case shows that conservative therapy may be effective. However, it has to be emphasised that this approach requires frequent clinical and duplex sonography follow-up every 3 to 6 months with oral anticoagulation.

Severe obstructive calcifications affecting the descending and suprarenal abdominal aorta without coexisting peripheral atherosclerotic disease – coral reef aorta

The case of a 58-year-old woman with leg claudication due to a very rare form of atherosclerosis affecting the descending thoracic and abdominal aorta – known as coral reef aorta – without involvement of the femoro-distal vessels is reported. The patient was treated with a polyester bifurcation graft from the proximal descending aorta to both common iliac arteries via a left dorsal minithoracotomy and a second left retroperitoneal approach. This unusual approach was chosen instead of direct aortic replacement in order to prevent paraplegia. In case of future visceral or left renal malperfusion the diseased artery can be connected to the prosthesis directly or by the use of an additional bypass graft. This would not be the case with a conventional axillo-bifemoral graft.

Long-term results of primary stent placement to treat infrarenal aortic stenosis

OBJECTIVE

To determine the safety and the long-term results of primary stent placement for localized distal aortic occlusive disease.

DESIGN

Retrospective observational study.

PATIENTS AND METHODS

From July 1998 to July 2005 17 patients (14 female and 3 men, mean age 57 years (39-80)) were treated for intermittent claudication. Five of these patients underwent additional endovascular treatment of focal iliac lesions.

RESULTS

Technical success defined as residual stenosis of less than 50% or a trans-stenotic systolic pressure gradient <10% was achieved in 14 of 17 (82%) patients. Major complications included dissection at the puncture site in one patient and thrombosis of additional iliac stents in another patient. Both of these complications were successfully treated. During a mean follow-up of 27 months (range 1-86), four patients had recurrence of symptoms due to in-stent restenoses (n=2), femoral (n=1) or iliac occlusion (n=1), respectively. By Kaplan-Meier analysis, primary aortic hemodynamic patency was 83% at 3 years. Secondary aortic hemodynamic patency was 100%. The primary clinical patency was 68% at 3 years.

CONCLUSION

Primary stent placement for distal aortic stenoses is an alternative to surgical treatment because of its high patency and relatively low complication rates.

Treatment of neurogenic claudication by interspinous decompression: application of the X STOP device in patients with lumbar degenerative spondylolisthesis

OBJECT

Interspinous process decompression (IPD) theoretically relieves narrowing of the spinal canal and neural foramen in extension and thus reduces the symptoms of neurogenic intermittent claudication (NIC). The purpose of this study was to compare the efficacy of IPD with nonoperative treatment in patients with NIC secondary to degenerative spondylolisthesis.

METHODS

The authors conducted a randomized controlled study in patients with NIC; they compared the results obtained in patients treated with the X STOP IPD device with those acquired in patients treated nonoperatively. The X STOP implant is a titanium alloy device that is placed between the spinous processes to reduce the canal and foraminal narrowing that occurs in extension. In a cohort of 75 patients with degenerative spondylolisthesis, 42 underwent surgical treatment in which the X STOP IPD device was placed and 33 control individuals were treated nonoperatively. Patients underwent serial follow-up evaluations. The Zurich Claudication Questionnaire (ZCQ), 36-Item Short Form Health Survey (SF-36), and radiographic assessment were used to determine outcomes. Two-year follow-up data were obtained in 70 of 75 patients. Statistically significant improvement in ZCQ and SF-36 scores was seen in X STOP device-treated patients but not in the nonoperative control patients at all postoperative intervals. Overall clinical success occurred in 63.4% of X STOP device-treated patients and only 12.9% of controls. Spondylolisthesis and kyphosis were unaltered.

CONCLUSIONS

The X STOP device was more effective than nonoperative treatment in the management of NIC secondary to degenerative lumbar spondylolisthesis.

Intravascular ultrasound-guided creation of re-entry sites to improve intermittent claudication in patients with aortic dissection

PURPOSE

To report percutaneous fenestration of aortic dissection flaps to relieve distal ischemia using a novel intravascular ultrasound (IVUS)-guided fenestration device.

CASE REPORTS

Two men (47 and 62 years of age) with aortic dissection and intermittent claudication had percutaneous ultrasound-guided fenestration performed under local anesthesia. Using an ipsilateral transfemoral approach, the intimal flap was punctured under real-time IVUS guidance using a needle-catheter combination through which a guidewire was placed across the dissection flap into the false lumen. The fenestration was achieved using balloon catheters of increasing diameter introduced over the guidewire. Stenting of the re-entry was performed in 1 patient to equalize pressure across the dissection membrane in both lumens. The procedures were performed successfully and without complications. In both patients, ankle-brachial indexes improved from 0.76 to 1.07 and from 0.8 to 1.1, respectively. Both patients were without claudication at the 3- and 6-month follow-up examination.

CONCLUSION

Percutaneous intravascular ultrasound-guided fenestration and stenting at the level of the iliac artery in aortic dissection patients with claudication is a technically feasible and safe procedure and relieves symptoms.

Balloon angioplasty versus implantation of nitinol stents in the superficial femoral artery

BACKGROUND

Because stent implantation for disease of the superficial femoral artery has been associated with high rates of late clinical failure, percutaneous transluminal angioplasty is preferred for endovascular treatment, and stenting is recommended only in the event of suboptimal technical results. We evaluated whether primary implantation of a self-expanding nitinol (nickel-titanium) stent yielded anatomical and clinical benefits superior to those afforded by percutaneous transluminal angioplasty with optional secondary stenting.

METHODS

We randomly assigned 104 patients who had severe claudication or chronic limb ischemia due to stenosis or occlusion of the superficial femoral artery to undergo primary stent implantation (51 patients) or angioplasty (53 patients). Restenosis and clinical outcomes were assessed at 6 and 12 months.

RESULTS

The mean (+/-SD) length of the treated segment was 132+/-71 mm in the stent group and 127+/-55 mm in the angioplasty group. Secondary stenting was performed in 17 of 53 patients (32 percent) in the angioplasty group, in most cases because of a suboptimal result after angioplasty. At 6 months, the rate of restenosis on angiography was 24 percent in the stent group and 43 percent in the angioplasty group (P=0.05); at 12 months the rates on duplex ultrasonography were 37 percent and 63 percent, respectively (P=0.01). Patients in the stent group were able to walk significantly farther on a treadmill at 6 and 12 months than those in the angioplasty group.

CONCLUSIONS

In the intermediate term, treatment of superficial-femoral-artery disease by primary implantation of a self-expanding nitinol stent yielded results that were superior to those with the currently recommended approach of balloon angioplasty with optional secondary stenting. (ClinicalTrials.gov number, NCT00281060.).

Percutaneous angioplasty of the superior gluteal artery for buttock claudication: A report of seven cases and literature review

BACKGROUND

Buttock claudication due to stenosis or occlusion of the superior gluteal artery is infrequent. The recent development of noninvasive gluteal duplex scanning, combined with aortoiliac angiography using oblique projections and the availability of low-profile devices for percutaneous transluminal angioplasty (PTA), led us to review our recent experience concerning the diagnosis and mid-term results of PTA for superior gluteal artery stenosis or occlusion.

METHODS

The files of all patients who had been treated in our department by PTA for superior gluteal artery stenosis or occlusion with buttock claudication were analyzed retrospectively, and any associated arterial lesions, morbidity, restenosis, or recurrent buttock claudication were noted. Outcomes were compared with published reports.

RESULTS

Retrospective review identified six patients (5 men, 1 woman; mean age, 64 years) with seven cases of buttock claudication (1 bilateral localization) who had undergone PTA within the past 2 years. There was no case of isolated buttock claudication. Buttock claudication was associated with impotence, thigh claudication, or calf claudication in seven cases. Gluteal duplex scans were performed for three of the patients diagnosed with two stenoses and one occlusion. Aortoiliac angiography revealed five superior gluteal artery stenoses and two occlusions. PTA without stenting was successful in all cases, without morbidity or mortality. During a mean follow-up of 13 months, restenosis occurred in one patient. A repeat PTA without stenting was successful, with resolution of the buttock claudication.

CONCLUSIONS

Buttock claudication due to superior gluteal artery stenosis is probably underestimated when gluteal duplex scanning and aortoiliac angiography with oblique projections are not performed. PTA gives good results, and the procedure can be repeated should restenosis occur.

Role of adhesion molecules in the induction of restenosis after angioplasty in the lower limb

OBJECTIVE

The adhesion molecules P selectin, E selectin, intercellular adhesion molecule, vascular cellular adhesion molecule (VCAM), and monocyte chemoattractant protein 1 play a important role in the development of arteriosclerotic lesions and are considered main contributors to restenosis after angioplasty. We expected that the serum levels of these markers would increase in the early phase of the first few weeks after angioplasty.

METHODS

We assessed prospectively the levels of soluble forms of adhesion molecules on the day before and then 24 hours and 2 and 4 weeks after angioplasty in arteries of the lower limb by using enzyme-linked immunosorbent assays. We investigated the distribution pattern of these markers in 44 patients (25 male and 19 female; age, 67.7 +/- 8.5 years [mean +/- SD]) presenting with intermittent claudication (Fontaine stage IIb). Twelve patients (27.3%) underwent diagnostic angiography, 32 (72.2%) received interventional treatment, 22 (68.8%) received balloon angioplasty, and 10 (31.2%) required stent placement.

RESULTS

Ten (31.3%) of the treated patients developed restenosis within 6 months. These patients had significantly higher levels of P selectin (P = .034), E selectin (P = .006), and VCAM (P = .050) at all time points. E selectin, VCAM, and monocyte chemoattractant protein 1 levels increased between 24 hours and 4 weeks after angiographic procedures, thus indicating that the angiographic procedure itself leads to activation and inflammation of the endothelium.

CONCLUSIONS

This study emphasizes a meaningful role of the adhesion molecules E selectin, P selectin, and VCAM as interesting contributors to restenosis formation after percutaneous transluminal angioplasty.

The Role of Coagulation and Inflammation After Angioplasty in Patients with Peripheral Arterial Disease

PURPOSE

Restenosis remains a frequent complication after angioplasty in peripheral arterial disease. Inflammation plays a critical role in the vascular response to injury. Effective medical treatment to improve patency after angioplasty is still elusive. The aims of this prospective clinical study were to investigate changes in blood coagulation and inflammatory markers after angioplasty and their significance for restenosis.

METHODS

Thirty-four patients with peripheral arterial disease underwent angioplasty of the iliac and superficial femoral arteries. Ten patients undergoing diagnostic angiography were included in the study as controls. Plasma levels of tissue factor, prothrombin fragment 1 + 2, D-dimer, P-selectin, C-reactive protein (CRP), and fibrinogen were analyzed before and after angioplasty. Patients were followed up with angiography after 6 months to assess restenosis.

RESULTS

CRP was elevated the day after angioplasty (6.6 mg/l, p = 0.0001) and tended to peak after 1 week (11 mg/l, p = 0.09). There was a significant increase of D-dimer and P-selectin 1-4 hr after angioplasty (0.4 mg/l, p = 0.001 and 68 ng/ml, p = 0.05, respectively). None of the biochemical markers was a statistically significant predictor of restenosis.

CONCLUSION

We have observed a much more prolonged inflammatory response than previously noted, but only minor changes in coagulation activity after angioplasty. The biochemical markers, before and after angioplasty, were not related to restenosis. Further studies are needed to delineate the molecular mechanisms behind these observations and their involvement in thrombosis and restenosis. If these pathways are further defined, improved treatment strategies, including antithrombotic treatments and statins, could be tailored to modulate postprocedural inflammation.

Parenteral therapy with lipo-ecraprost, a lipid-based formulation of a PGE1 analog, does not alter six-month outcomes in patients with critical leg ischemia

PURPOSE

Eicosanoids with vasodilating and angiogenic properties have been postulated to be effective therapies for critical leg ischemia (CLI) secondary to atherosclerotic peripheral arterial disease. The ability to deliver active drug to the site of action at adequate doses for sufficient duration has been a major limitation in the clinical development of such therapies. Lipo-ecraprost is a lipid-encapsulated prostaglandin E1 prodrug with the potential to deliver active prostaglandin to the site of critical arterial ischemia. The current trial was designed to test the hypothesis that lipo-ecraprost would improve amputation-free survival in patients with CLI who had no revascularization options.

METHODS

The study was randomized, multicenter, double blind, and placebo controlled. Patients who met clinical and hemodynamic criteria were randomized to receive placebo or lipo-ecraprost (60 microg) administered intravenously on each of 5 days per week, for a total of 8 weeks. The study's primary endpoint was the rate of a composite end point of death or amputation above the level of the ankle at 180 days (6 months).

RESULTS

The study was terminated on a recommendation from the Data and Safety Monitoring Board after the completion of a protocol-specified interim analysis for futility. At the time of termination, 383 of the planned 560 patients had been randomized, of which 379 received at least one dose of study medication and thus were included in the intention-to-treat population. Twenty-three patients were lost to follow-up and were not available for 6-month assessments. At 6 months of follow-up, there were 23 amputations in the 177 patients who received placebo, and 29 amputations in the 179 patients randomized to lipo-ecraprost. At 6 months, 10 deaths had occurred in the placebo group and 18 deaths had occurred in the lipo-ecraprost arm. Changes in lower-extremity hemodynamics over the 6-month study period did not differ between the placebo and lipo-ecraprost treatment arms.

CONCLUSION

Intensive treatment with lipo-ecraprost failed to modify the 6-month amputation rate in patients with CLI who were not candidates for revascularization.

The Long-term Prognostic Value of the Resting and Postexercise Ankle-Brachial Index

BACKGROUND

Peripheral arterial disease is associated with a high incidence of cardiovascular mortality. Peripheral arterial disease can be detected by using the ankle-brachial index (ABI). This study assessed the prognostic value of the postexercise ABI in addition to the resting ABI on long-term mortality in patients with suspected peripheral arterial disease.

METHODS

In this prospective cohort study of 3209 patients (mean +/- SD age, 63 +/- 12 years; 71.1% male), resting and postexercise ABI values were measured and a reduction of postexercise ABI over baseline resting readings was calculated. The mean follow-up was 8 years (interquartile range, 4-11 years).

RESULTS

During follow-up, 1321 patients (41.2%) died. After adjusting for clinical risk factors, lower resting ABI values (hazard ratio per 0.10 lower ABI, 1.08; 95% confidence interval [CI], 1.06-1.10), lower postexercise ABI values (hazard ratio per 0.10 lower ABI, 1.09; 95% CI, 1.08-1.11), and higher reductions of ABI values over baseline readings (hazard ratio per 10% lower ABI, 1.12; 95% CI, 1.09-1.14) were significantly associated with a higher incidence of mortality. In patients with a normal resting ABI (n = 789), a reduction of the postexercise ABI by 6% to 24%, 25% to 55%, and greater than 55% was associated with a 1.6-fold (95% CI, 1.2-2.2), 3.5-fold (95% CI, 2.4-5.0), and 4.8-fold (95% CI, 2.5-9.1) increased risk of mortality, respectively.

CONCLUSIONS

Resting and postexercise ABI values are strong and independent predictors of mortality. A reduction of postexercise ABI over baseline readings can identify additional patients (who have normal ABI values at rest) at increased risk of subsequent mortality.

Risk factors for poor collateral development in claudication

The objective of this retrospective, cross-sectional study was to determine risk factors for poor collateral development in patients with claudication. The authors listed all patients with calf claudication who had undergone angiography in this hospital between 1999 and 2001 and extracted those with superficial femoral artery (SFA) occlusion, a popliteal artery without major lesions, and at least 1 patent calf artery. Forty-five patients met the criteria, and concomitant disease and claudication characteristics, ankle/brachial index (ABI) and number of outflow vessels were recorded. Three blinded observers calculated the number of collaterals on the angiograms, and the collateral count was related to the other factors by use of regression analysis. The mean patient age was 69 years (SD 11), and 62% were women. Their walking distance was 90 m (77) and ABI 0.47 (0.15). Thirty-three percent had diabetes and 50% had duration of symptoms longer than 5 years. The mean number of collaterals bypassing the occlusion was 15.1 (SD 4.8). Univariate regression analysis indicated an association (p <0.08) between few collateral vessels and diabetes, short duration of symptoms, current smoking habits, and old age. In the multivariate analysis only diabetes and short duration of symptoms were related to having few collaterals. In patients with claudication and SFA occlusion, few collaterals from the deep femoral artery appear to be associated with having diabetes and a short duration of symptoms.