Pulse Volume Recordings Research Articles

Never amputate without consultation of a vascular surgeon.

Lower limb ischaemia is one of the determinants in the development of diabetic foot ulcers and the most important factor preventing their healing. There are a number of misleading factors masking the presence of atherosclerotic disease and tissue damage; these are reduced inflammatory response to infection, autosympathectomy and mediasclerosis, which all diminish the clinical suspicion of ischaemia. Therefore, adequate assessment of the lower limb circulation should be routinely performed in complicated diabetic foot. This evaluation can often be made with simple methods. In addition to clinical examination ankle/brachial pressure index, systolic toe pressure, plethysmographic pulse volume recordings and simple hand-held Doppler auscultation are most often sufficient to make a decision as to whether angiography is needed or not. Duplex examination can give more profound information on the severity and extent of arterial occlusive disease, but the method is strongly user-dependent. Early vascular consultation is mandatory in diabetic foot work-up and should be undertaken within 2 weeks if a new skin lesion shows no tendency to heal. Long bypass grafting procedures and microvascular free flap techniques have been shown to achieve excellent results in relieving critical leg ischaemia, even in the presence of large foot lesions, and should be used to prevent major amputation. The timing of various procedures is a controversial issue. Feet with small ulcers or restricted dry gangrena can be revascularised first, with minor amputations and local surgery of the ulcer being done thereafter. In the septic neuroischaemic foot, major amputation may be unavailable but if the infection is not immediately life-threatening the infected part of the foot should be drained and debrided properly and left wide open, sometimes with a guillotine amputation in order not to risk the bypass graft, which can be done a couple of days later.

Evaluation of Common Femoral Endarterectomy for the Management of Focal Atherosclerotic Disease

Although uncommon, focal atherosclerotic lesions of the common femoral artery (CFA) are frequently responsible for disabling ischemic symptoms owing to their proximal location. The authors retrospectively identified 51 patients who between 1983 and 1995 underwent 53 common femoral endarterectomies (CFE) for occlusion (19) or hemodynamically significant (< 70%) stenoses (34). Operative indications included disabling claudication (21%), rest pain (45%), and nonhealing ulcers (34%). In Group 1, patients underwent CFE alone (37 limbs); in Group 2, CFE was combined with a distal bypass (16 limbs). CFA patency was ascertained by physical examination, limb pressures, and pulse volume recordings, with a mean follow-up of 40 months. Cumulative life-table CFA primary patency rates for all extremities were 95%, 85%, and 82% at 1, 3, and 5 years. CFA patency at 1, 3, and 5 years was 94%, 82%, and 77% in Group 1, compared to 100%, 92%, and 92% in Group 2 (p = 0.33, p = 0.34, p = 0.26). Sixty percent of patients with late failures were found to have an inherited hypercoagulable state. The 5-year limb salvage rate was 90% in Group 1 and 94% in Group 2 (p = 0.9). Postoperatively, limbs became asymptomatic, clinically improved, or deteriorated in 35%, 46%, and 19%, respectively of Group 1, compared with 44%, 50%, and 6% of Group 2 (p = 0.6). Focal atherosclerotic lesions of the common femoral artery can be successfully managed by common femoral endarterectomy with acceptable 5-year patency, limb salvage rates, and relief of symptoms.

Comparison of treatment plans for lower extremity arterial occlusive disease made with electrocardiography-triggered two-dimensional time-of-flight magnetic resonance angiography and digital subtraction angiography

Background: The purpose of the study was to determine whether preoperative treatment plans for patients with lower extremity ischemia can be made with electrocardiography (EKG)-triggered two-dimensional (2D) time-of-flight (TOF) magnetic resonance angiography (MRA) as accurately as digital subtraction angiography (DSA). Methods: Forty patients were prospectively evaluated with the combination of EKG-triggered 2D TOF MRA, DSA, and pulse volume recordings. Blinded reviewers graded arterial segments for disease severity. Accuracy of separate MRA- and DSA-based treatment plans was compared with the procedures performed based on all available information. Results: There was an 86% exact match between MRA- and DSA-based plans (92% MRA and 94% DSA accuracy). The MRA-based plan accurately predicted 90% of suprainguinal and 95% of infrainguinal procedures, whereas the DSA-based plan accurately predicted 100% of suprainguinal and 85% of infrainguinal procedures. Two-year primary patency was 83% for all procedures. Radiologists’ review of disease severity resulted in a mean exact correlation between studies of 81% (κ = 0.64). The agreement between radiologists interpreting the MRA was 84% (κ = 0.7) compared with 82% (κ = 0.66) for the DSA. Conclusions: MRA- and DSA-based preoperative management plans were of comparable efficacy. Significant interobserver variability was seen with the interpretations of both preoperative studies. EKG-triggered 2D TOF MRA can be used to plan arterial reconstructions; however, all patients require arterial pressure measurements prior to suprainguinal repair and confirmatory intraoperative angiography during infrainguinal revascularization.

When is urokinase treatment an effective sole or adjunctive treatment for acute limb ischemia secondary to native artery occlusion?

Background: Intra-arterial thrombolytic therapy is currently a therapeutic option for the treatment of acute limb ischemia. A recent large prospective randomized trial (TOPAS) comparing lytic therapy and operative intervention showed that both forms of treatment had similar results in terms of amputation-free survival. However, the exact role for lytic treatment is unclear. Method: Over a 4-year period we treated 60 cases of acute limb ischemia in 57 patients secondary to native artery occlusion with thrombolytic therapy with urokinase. All patients were evaluated at 1 week, 1 month, and then at 3-month intervals posttreatment. Follow-up evaluations included pulse examination, pulse volume recordings, and duplex examinations to confirm arterial patency. No patients were lost to follow-up with a range of 8 to 54 months (mean 26). Results: Of these 60 native arterial occlusions, complete lysis was achieved in 46 cases (76%). Of these 46 cases, 18 required lysis only, 19 cases (9 iliac, 7 superficial femoral artery (SFA), and 3 popliteal) required angioplasty of lesions uncovered by clot lysis, and 9 patients had lysis and angioplasty of iliac arteries followed by infrainguinal bypasses. Eight of the 57 patients (14%) who had been asymptomatic presented with symptoms limited to new onset claudication, all of which were successfully lysed. Cumulative patency for the 43 successful cases was 90% ± 5% at 1 year and 75% ± 4% at 2 years. The 1-year amputation-free survival for all native artery occlusions was 85% ± 6%. Conclusion: Thrombolysis with urokinase simplified the treatment of native arterial occlusion proving to be the sole therapy in 18 (29%) patients or a valuable adjunct by facilitating the angioplasty of arterial lesions and avoiding open surgery in 60% of patients treated. In addition, the correction of inflow lesions reduced the magnitude of required subsequent bypass procedures to achieve limb salvage. In conclusion, successful thrombolysis of native artery occlusion provided durable arterial patency and limb salvage, particularly in patients with new onset claudication.

PERIPHERAL VASCULAR DISEASE AFTER PANCREAS TRANSPLANT

668 The role of Ptx in altering the course of peripheral vascular disease (PVD) is uncertain. We evaluated a cohort of PTx recipients to determine the risk factors for peripheral vascular disease progression or complications after PTx. A retrospective review of all PTx performed from 1990 to 1997 was performed. Exclusions were made for graft or patient survival less than one year. Charts were reviewed for the presence of coronary artery disease (CAD), hypertension (HTN), hyperlipidemia, alcohol or tobacco use, duration of diabetes and dialysis. Post-Ptx variables evaluated include length of graft and patient survival, yearly cholesterol, LDL, HDL, and triglyceride levels. Annual non-invasive lower extremity vascular studies were obtained in most and evaluated for progression of PVD (worsening of pulse volume recordings or ABI reduction). Outcome was evaluated by pro-gression of PVD on non-invasive testing, amputation, or revascularization. Data is presented as mean±SEM. A p value ≤ 0.05 was considered significant. 62 patients, age 37.3±1 years, duration of diabetes 23.8±1 years were included. Forty one (66%) patients were males, 50 patients (80.6%) were on dialysis for 13.9±2 months. Pre-PTx HTN, hyperlipidemia, CVA, CAD, amputations and vascular reconstructions were identified in 57 (91.9%), 17 (27.4%), 2 (3.2%), 14 (22.6%), 6(9.7%) and 2(3.2%) patients respectively. 14 patients(22.6%) required amputation, 9(14.5%) underwent bypass and 19(30.6%) had PVD progression on vascular studies post-PTx. LDL at one year was higher in those with PVD progression 144.9±9 vs. 116.1±7 mg/dl (p=0.017), in patients requiring amputation 153.7±14 vs. 121.2±6 mg/dl(p=0.033) and in those requiring bypass 165±16 vs. 120.4±5 mg/dl(p=0.005). Cholesterol at one year was elevated in those wth PVD progression and those undergoing post-PTx bypass 221.9±12 vs. 187.7±7 mg/dl (p=0.017) and 232.3±23 vs. 194.7±7 mg/dl(p=0.048) respectively. One year triglyceride levels were elevated in PTx patients with PVD progression and in those requiring bypass 156.6±22 vs. 101.9±11 (p=0.022) and 175.5±48 vs. 112.3±10 (p=0.046) respectively. Multiple regression analysis identified only pre-PTx CVA (p=0.011) and CAD (p=0.006) as predictive of post-PTx PVD progression. No variables were found predictive of post-PTx bypass or amputation. Pre-PTx CAD and CVA were found to identify recipients at increased risk for progression of PVD. Improved control of hyperlipidemia may provide a therapeutic strategy for altering the progression of PVD in this population.

Percutaneous transluminal angioplasty for the treatment of limb threatening ischemia: Do the results justify an attempt before bypass grafting?

Purpose: Results of percutaneous transluminal angioplasty (PTA) in selected cases have been reported to be equal or superior to those of arterial bypass graft surgery, with a lower morbidity and mortality. We performed PTA of stenotic or occlusive lesions in patients with limb-threatening ischemia, hoping to improve our overall success and decrease morbidity in this group of patients. The results of PTA in the limb-salvage setting was evaluated. Methods: From 1992 to 1995, 307 PTAs were performed in 257 patients. One hundred sixty-one (63%) patients had diabetes mellitus, and 32 (12%) patients had renal failure. All patients were evaluated by means of pulse volume recordings and ankle brachial indices at 1 and 6 weeks after PTA and at 3 month intervals thereafter. Seventeen patients (9%) were lost to follow-up. The continued success or failure of PTA was defined by means of noninvasive vascular laboratory criteria, patency by means of pulse examination, the need for subsequent bypass grafting across the index lesion, and limb salvage. Results: The 1-year patency rates for external iliac PTAs (56%) were significantly lower ( P < .05) than those for common iliac PTAs (87%). Infrainguinal PTAs at the femoral, popliteal, and tibial level had 1-year patency rates of less than 15%. Conclusion: Common iliac artery PTA is justified in most cases in which it is feasible. However, when PTAs are performed below the inguinal ligament, the results are markedly worse. One-year patency rates of PTA in this group of patients with threatened limbs are inferior to the patency rates of arterial bypass grafts, even when these bypasses are performed with a prosthetic material. PTA should not be considered as a primary treatment modality for patients with infrainguinal arterial occlusive disease who also have limb-threatening ischemia, except in unusual circumstances. (J Vasc Surg 1998;28:1066-71.)

Analysis of digital pulse-volume recordings with radial and ulnar artery compression.

The vascular noninvasive studies of 289 consecutive cardiac surgery patients were reviewed to better understand hand blood-flow physiology in an older population with vascular disease. The radial artery was found to be more important to pulsatile digital blood flow than the ulnar artery. In more than 20 percent of hands, the thumb and the index and fifth fingers lost pulsatile blood flow with radial artery compression at the wrist compared with only 5 percent with ulnar artery compression. The maintenance of pulsatile digital blood flow did not follow anatomic patterns of blood vessels previously presumed to be of paramount importance. The hand acts more like a single vascular bed than it does like two separate systems with a connecting arch.

Arterial reconstruction: justified for patients with intermittent claudication?

The objective of this study was to evaluate the effects of arterial reconstruction in patients with intermittent claudication. A total of 243 patients (305 limbs) underwent lower extremity vascular reconstruction at our institution from 1979 to 1995. They were assessed by physical examination, pulse volume recordings, segmental pressure, Duplex ultrasonography, and intravenous subtraction arteriography to evaluate the effects of arterial reconstruction. Surviving patients (220 limbs) were enrolled for evaluation of outcome during the follow-up period. There were 59 deaths during the follow-up period. The cumulative life-table 5-year patency rates were 90% +/- 3%, 73% +/- 6%, and 74% +/- 10% for aortoiliac, infrainguinal, and aortofemorodistal arterial reconstructions, respectively. Among 129 repairs in the aortoiliac region, Fontaine stages I, II, and III were found in 109 limbs (84.5%), 17 limbs (13.2%), and 2 limbs (1.5%), respectively. There was one (0.7%) minor amputation. There was Fontaine stage I in 50 limbs (76.9%), Fontaine stage II in 14 limbs (21.5%), and Fontaine stage III in 1 limb (1.5%) for repairs in the infrainguinal region. Among the 26 aortofemorodistal repairs, there was Fontaine stage I in 21 limbs (81%) and Fontaine stage II in 5 limbs (19%). There was a statistically significantly higher incidence of Fontaine stage I than Fontaine stage II or III in aortofemoral, infrainguinal, and aortofemorodistal arterial reconstructions (p < 0.0001). Arterial reconstruction for patients at Fontaine stage II offered benefits and improved quality of life at follow-up. Arterial reconstruction for patients at Fontaine stage II offers benefits and improved quality of life at follow-up. It was concluded that the significant improvement in quality of life after arterial reconstruction warrants continued use of the procedure in patients with intermittent claudication.

Peripheral arterial disease as a predictor of outcome after renal transplantation.

Our aim was to assess the prevalence of symptomatic and asymptomatic peripheral occlusive arterial disease (POAD) in 129 consecutive diabetic (n = 34) and nondiabetic (n = 95) patients undergoing renal transplantation. The association of pre-existent POAD and complaints of claudication, lower limb amputations, and graft and patient survival were evaluated during a 5-year follow up. A questionnaire on walking capacity, ankle/brachial (ABI) and toe/brachial (TBI) pressure indices as well as the pulse volume recording (PVR) at the ankle were used to assess resting haemodynamics and the presence of POAD 4 days after the transplantation. Unquestionable ischaemia was encountered in 5 (4%) patients all with a history of intermittent claudication and an ABI equal or below 0.77. While using assessment methods not affected by vessel calcification, i.e. toe pressures and PVR damping, a many-fold frequency of arterial disease was observed when compared to previous studies. TBI below 0.65 was found in 11 of diabetic (32%) and in 15 of the others (16%), and a PVR amplitude below 5 min in 28 of diabetics (82%) and in 34 of non-diabetics (36%). During the 5-year follow up, abnormal TBI and PVR values and diabetes at the time of transplantation were the greatest risk factors for proximal foot amputations. The low TBI levels also indicated a shortened patient survival. However, transplant function was not affected by the presence of abnormal haemodynamic indices at the time of transplantation.

Peripheral arterial disease as a predictor of outcome after renal transplantation

Abstract Our aim was to assess the prevalence of symptomatic and asymptomatic peripheral occlusive arterial disease (POAD) in 129 consecutive diabetic (n= 34) and non-diabetic (n= 95) patients undergoing renal transplantation. The association of pre-existent POAD and complaints of claudication, lower limb amputations, and graft and patient survival were evaluated during a 5-year follow up. A questionnaire on walking capacity, ankle/brachial (ABI) and toe/brachial (TBI) pressure indices as well as the pulse volume recording (PVR) at the ankle were used to assess resting haemodynamics and the presence of POAD 4 days after the transplantation. Unquestionable ischaemia was encountered in 5 (4 %) patients all with a history of intermittent claudication and an ABI equal or below 0.77. While using assessment methods not affected by vessel calcification, i.e. toe pressures and PVR damping, a many-fold frequency of arterial disease was observed when compared to previous studies. TBI below 0.65 was found in 11 of diabetic (32 %) and in 15 of the others (16%), and a PVR amplitude below 5 min in 28 of diabetics (82 %) and in 34 of non-diabetics (36 %). During the 5-year follow up, abnormal TBI and PVR values and diabetes at the time of transplantation were the greatest risk factors for proximal foot amputations. The low TBI levels also indicated a shortened patient survival. However, transplant function was not affected by the presence of abnormal haemodynamic indices at the time of transplantation.

Clinical assessment of the patient with claudication: the role of the vascular laboratory.

The noninvasive vascular laboratory aids in the evaluation of patients with peripheral arterial disease (PAD). Several qualitative and quantitative noninvasive tests are useful for diagnosing PAD and monitoring patients' response to treatment. These tests include Doppler ultrasonography, pulse volume recording, segmental blood pressure measurement, exercise testing, post-occlusive reactive hyperemia testing, transcutaneous oximetry and color-assisted ultrasound imaging. Each test has specific utility and can be used either individually or in combination with other noninvasive tests to obtain information about the hemodynamic and functional severity of peripheral atherosclerosis in patients with claudication.

Percutaneous transluminal angioplasty and primary stenting of the iliac arteries in 288 patients

This study reports the initial and late results of percutaneous transluminal angioplasty (PTA) and intravascular stenting for atherosclerotic occlusive disease of the iliac arteries. The preprocedural and postprocedural clinical records, arteriograms, segmental limb pressure measurements (ankle-brachial [ABI] and thigh-brachial [TBI] indexes), and pulse volume recordings of 288 patients who underwent PTA and primary stenting of the common iliac (354, 69.4%) and external iliac (156, 30.6%) arteries were reviewed. Initial and late clinical, hemodynamic, and angiographic success were assessed by objective criteria. Data on patients who underwent unsuccessful attempts at iliac stent placement are unavailable; results are not reported on an intent-to-treat basis. Clinical follow-up data (mean, 11.9 months) are available for 268 of 288 patients (93.1%) and for 394 of 424 limbs (92.9%). The initial success rates, as determined by TBI, ABI, and clinical limb status, were 90.2%, 87.8%, and 74.6%, respectively. The Kaplan-Meier estimates of angiographic patency (101 arteries) were 96%, 81%, and 73% at 6, 12, and 24 months. Cumulative patency rates were 84%, 76%, and 57% on the basis of TBI, ABI, and clinical limb status at 24 months. Factors associated with initial success included the need for multiple stents (p = 0.0001), a higher degree of initial stenosis (p = 0.0001), lower severity of baseline ischemia (p = 0.007), younger age (p = 0.0015), and the preprocedural patency of the ipsilateral superficial femoral artery (p = 0.002). A higher degree of initial stenosis (p < 0.001) and superficial femoral artery patency (p = 0.004) were also associated with late success. PTA and stenting of the iliac arteries is associated with reasonable angiographic, hemodynamic, and clinical success. The outcome is favorably affected by higher initial severity of stenosis and greater extent of disease, lower severity of baseline ischemia, younger age, and by patency of the ipsilateral superficial femoral artery.

Delay in Improvement of Ankle-Arm Index and Ankle Waveforms after Lower-Extremity Revascularization

Ankle-arm index (AAI) and pulse volume recording (PVR) are commonly used in the early postoperative period to measure the outcome after lower-extremity revascularization. They are also used in addition to duplex scan for long-term follow-up of these patients. We noticed that in some patients the AAI and/or PVR after revascularization procedures did not improve immediately after surgery, but took 24 hours or longer to do so. We retrospectively reviewed the records of 47 patients who underwent various lower-extremity revascularization procedures and found that out of 20 patients who had AAI and/or PVR measured in the recovery room, 8 patients took 24 hours and 1 patient took more than 24 hours for maximal improvement of their AAI and/or PVR. This may be related to vascular spasm, and knowledge of this delayed improvement is important in preventing errors during follow-up.

Microcirculatory Compensation to Progressive Atherosclerotic Disease

The precapillary resistance in the skin of the foot increases with standing. This mechanism, termed the venoarterial reflex (VAR) restricts arterial inflow, and avoids an excessive rise in capillary pressure. This study tests the hypothesis that there is microcirculatory compensation to atherosclerotic disease of increasing severity. Foot skin perfusion (FSP) was measured in 100 limbs with a laser Doppler placed on the plantar aspect of the great toe. Limbs were categorized as normal (n = 31) with an ankle brackial index (ABI) > or = 0.96, claudicants (n = 42) ABI 0.5-0.86, and critical ischemia (n = 27) with an ABI < or = 0.49 or a pulse volume recording consistent with severe peripheral vascular disease and symptoms of rest pain or tissue loss. Segmental Doppler pressures and pulse volume recordings were performed prior to laser Doppler measurements. Subjects with clinical signs or symptoms of chronic venous insufficiency were excluded. The resting foot skin perfusion was measured in the horizontal and dependent position, with the patient supine and sitting. Comparisons within categories were done using Wilcoxon matched pairs signed rank test and between groups with Mann-Whitney U test for unpaired data. Differences were considered significant if they exceeded the 95% confidence level (p value < or = 0.05). Resting supine skin perfusion was similar between nondiabetic normals and claudicants and diabetic normals and claudicants. There was a significant decrease in the foot skin perfusion (mean FSP +/- SEM) in the normal limb with a change from the supine (7.8 +/- 2.2 ml/min/100 g) to the dependent (2.8 +/- 0.6 ml/min/100 g) position indicating an intact VAR. This was absent in 33% of the limbs with claudication. Limbs with critical ischemia demonstrated an increase in FSP with dependency (supine 4.0 +/- 1.0 ml/min/100 g) versus dependent (8.4 +/- 1.8 ml/min/100 g) and was present in both diabetic and nondiabetic limbs. Microcirculatory compensation occurs early in atherosclerotic limbs. Although supine FSP is similar in normals and claudicants, a greater percentage of claudicants demonstrate a loss of the VAR. Critically ischemic limbs have increased FSP in the dependent position. These observations indicate that there are microcirculatory alterations in limbs with claudication and assist in explaining why patients with ischemic rest pain obtain relief and develop edema with dependency.

Endovascular aortounifemoral grafts and femorofemoral bypass for bilateral limb-threatening ischemia.

Although axillobifemoral bypass procedures have a lower mortality rate than aortobifemoral bypass procedures, they are limited by decreased patency, moderate hemodynamic improvement, and the need for general anesthesia. This report describes an alternative approach to bilateral aortoiliac occlusive disease using unilateral endovascular aortofemoral bypass procedures in combination with standard femorofemoral reconstructions. Seven patients who had bilateral critical ischemia and tissue necrosis in association with severe comorbid medical illnesses underwent implantation of unilateral aortofemoral endovascular grafts, which were inserted into predilated, recanalized iliac arteries. The proximal end of the endovascular graft was fixed to the distal aorta or common iliac artery with a Palmaz stent. The distal end of the graft was suture-anastomosed to the ipsilateral patent outflow vessel, and a femorofemoral bypass procedure was then performed. All endovascular grafts were successfully inserted through five occluded and two diffusely stenotic iliac arteries under either local (1), epidural (5), or general anesthesia (1). The mean thigh pulse volume recording amplitudes increased from 9 +/- 3 mm to 30 +/- 7 mm and from 6 +/- 2 mm to 26 +/- 4 mm ipsilateral and contralateral to the aortofemoral graft insertion, respectively. In all cases the symptoms completely resolved. Procedural complications were limited to one local wound hematoma. No graft thromboses occurred during follow-up to 28 months (mean, 17 months). Endovascular iliac grafts in combination with standard femorofemoral bypass grafts may be an effective alternative to axillobifemoral bypass in high-risk patients who have diffuse aortoiliac occlusive disease, particularly when bilateral axillary-subclavian disease is present.

Elevated Lipoprotein(a) and increased incidence of restenosis after femoropopliteal PTA. Rationale for the higher risk of recurrence in females?

It has been shown that the incidence of recurrent stenosis following successful percutaneous transluminal coronary angioplasty (PTCA) is correlated with serum Lipoprotein(a) [Lp(a)] levels. The aim of the present study was to examine the influence of Lp(a) on restenosis after primarily successful femoropopliteal PTA. One hundred and thirty nine consecutive patients with peripheral arterial occlusive disease (PAOD) and successful femoropopliteal PTA were studied. Follow-up included clinical examination and non-invasive laboratory testing (pulse volume recordings, ankle-brachial arterial pressure measurement) in every patient before and after 1, 3, 6 and 12 months following intervention. Duplex sonography was performed 1 year after PTA. Suspicion of restenosis (≥ 50% diameter reduction) was verified by angiography. Lp(a) was determined using ELISA technique (mg/dl). Twelve months after successful PTA no restenosis was found in 82 patients (59%: group A). The one-year recurrence rate of 41% (group B) was due to significant restenosis in 35 patients (25%) and reocclusion in 22 patients (16%). The corresponding mean values ± S.E.M. for Lp(a) were as follows: group A, 28 ± 5.3; group B, 59 ± 11 ( P < 0.01). Women showed a higher frequency of recurrences (55%) versus men (30%, P < 0.01) also corresponding with a higher Lp(a) level (51.8 ± 8 versus 32.7 ± 5; P < 0.05). Furthermore Lp(a) aggravated the well known increased risk for recurrence in multiple stenoses or occlusions of ≥ 5 cm in length. There were no significant differences between groups A and B with respect to age, diabetes, hyperlipidaemia, obesity and cigarette smoking. The results support the view that Lp(a) is an independent risk factor for recurrence after PTA in the femoropopliteal area. It might also be a causal basis for the higher incidence of recurrences in female PAOD patients.

Duplex ultrasonography to diagnose failing arterial prosthetic grafts

Although several reports have documented the usefulness of a surveillance program with duplex ultrasonography (DU) to diagnose failing autologous vein bypasses, the effectiveness of DU to detect failing arterial prosthetic grafts has not been confirmed. We attempted to determine whether our program, which included DU and other noninvasive techniques (NonDU), was useful for this purpose. Between July 1, 1991, and September 30, 1994, 85 prosthetic bypasses in 59 patients performed for lower extremity ischemia were entered into a graft surveillance protocol. There were 35 femoropopliteal, 16 femorotibial, 15 iliofemoral, 13 axillofemoral, and 6 femorofemoral bypasses. Both DU and NonDU were performed 1 week and every 3 months after the initial bypass or after graft revision. NonDU criteria of a failing graft included changes in symptoms or pulses, decreased ankle/brachial index greater than 0.15, or diminution of ankle pulse volume recordings greater than 50%. Normal grafts were bypasses that had less than 50% stenosis documented by arteriography or remained patent. Problem grafts were those that required revision or thrombosed before intervention. Follow-up of patient grafts ranged between 3 and 36 months (mean, 11 months). DU predicted 17 (81%) of 21 problem grafts versus only 5 (24%) diagnosed by NonDU (p = 0.001). Lesions associated with these 21 grafts were perianastomotic in 10 cases, in adjacent inflow or outflow arteries in 8 cases, and intrinsic to the graft in 3 cases. The likelihood of a graft thrombosing in the presence of a normal test was 7% (4 of 58) for DU compared with 21% (16 of 76) for NonDU (p = 0.04). DU is more sensitive than NonDU in predicting failure of prosthetic grafts. This study suggests that DU should routinely be performed as part of a surveillance program for peripheral arterial prosthetic bypasses.

Continuous Pulse Amplitude Monitoring of Infrainguinal Bypass Grafts in the First 24 Postoperative Hours

To evaluate continuous pulse amplitude monitoring (CPAM) as a method for early postoperative graft surveillance following infrainguinal bypass surgery, a prospective observational study was carried out in 34 consecutive infrainguinal bypass grafts. CPAM tracings were compared with pre- and postoperative pulse palpation, ankle/brachial index (ABI) measurements, and pulse volume recordings (PVR). The utility of each method was defined by its ability to demonstrate graft patency in the first 24 hours. Pulse palpation was considered a useful monitoring tool if a postoperative pedal pulse was found in the absence of palpable preoperative pulses. The ABI qualified in this respect if a postoperative increase of at least 0.25 could be demonstrated; for PVR tracings an increase of at least one category was required. The utility of CPAM was established by an increase of at least 5 mm compared to the preoperative values. There were no early graft failures. We were therefore unable to calculate the ability of the studies to predict graft failure. The percentages (95% confidence limits) for which pulse palpation, ABI, and PVR were found capable of demonstrating graft patency were 50% (range 34% to 66%), 53% (range 36% to 70%), and 71% (range 54% to 83%), respectively. CPAM appeared to be far superior to these three methods with a utility of 94% (range 81% to 98%; p < 0.05). Patient and operator acceptability of CPAM was high. Skin pressure problems are a potential risk if the CPAM probe is left attached to the skin for more than 24 hours. CPAM was a valuable and reliable means of monitoring infrainguinal vascular reconstructions. Apart from being inexpensive, continuous, objective, and simple, CPAM is noninvasive and painless. It is advisable to remove the probe 24 hours after surgery, when the most crucial period for graft monitoring has passed.

Use of magnetic resonance angiography for the preoperative evaluation of patients with infrainguinal arterial occlusive disease

This study was designed to determine whether magnetic resonance angiography (MRA) will allow preoperative management decisions without the need for contrast arteriography in patients with lower extremity ischemia caused by infrainguinal arterial occlusive disease. Forty-five patients with lower extremity ischemia in 50 limbs were evaluated by both two-dimensional time-of-flight MRA and intraarterial digital subtraction angiography (DSA) between February 1992 and June 1995. Independent management plans were based on clinical presentation, pulse volume recordings, and separate reviews of the MRA and DSA. Of 50 limbs, 23 required arterial bypass, 19 percutaneous transluminal angioplasty, 5 patch angioplasty, and 3 amputation. MRA and DSA correlated exactly in 89.5% of infrainguinal arterial segments, whereas interpretations disagreed in 10.5% of arterial segments. Mismatches that had an influence on patient treatment decisions occurred in only 8 (2.3%) of 352 arterial segments. Independent MRA- and DSA-based revascularization plans agreed in 45 (90%) extremities. MRA predicted the level of arterial reconstruction in all 23 limbs that required arterial bypass. MRA identified focal stenoses amenable to percutaneous transluminal angioplasty in 18 (94.7%) of the 19 limbs that ultimately underwent percutaneous transluminal angioplasty. A strategy of preoperative planning by MRA with confirmatory intraoperative arteriography would represent a 31% cost savings per patient at our institution while eliminating the morbidity of preoperative DSA. When used in combination with the patient's physical examination and segmental limb pressures with plethysmography, MRA is sufficient for planning infrainguinal arterial bypass procedures and selecting patients for percutaneous transluminal angioplasty.

Mid-term and long-term results with directional atherectomy of vein graft stenoses

The purpose of this study was to evaluate the outcomes of our 6-year experience with directional atherectomy used for treatment of stenoses in infrainguinal vein grafts. From March 1988 to April 1994, 52 directional atherectomy procedures were undertaken in 42 patients to treat 67 stenoses in 44 vein grafts. Follow-up consisted of periodic physical examinations and graft surveillance; ankle/brachial indexes, pulse volume recordings, and color-flow duplex ultrasonography. Follow-up angiography (n = 18) was performed for recurrent symptoms, reproducible drop in ankle/brachial index of greater than 0.15, a twofold to threefold focal increase in peak systolic velocity, or incidentally during evaluation of the opposite leg. Forty-nine of 52 (94%) procedures were technically successful. In two the residual diameter stenosis was greater than 30%, and in one atherectomy could not be performed. Complications were minor in six (11%) and major in three (6%): two acute graft occlusions and one delayed pseudoaneurysm at the atherectomy site. There were no deaths at 30 days. With a mean follow-up of 21 +/- 18 months, 36 of 44 grafts (82%) remained patent without restenosis; 6 others were patent but considered "failed"--5 (11%) with restenosis, 1 with a pseudoaneurysm; and 2 grafts (5%) occluded. Clinically 33 of 44 extremities (75%) were asymptomatic during follow-up. Claudication improved in five, recurred in three, and was unchanged in one. There was one below-knee amputation. Life-table analysis including all 52 procedures reveals cumulative primary atherectomy patency rates for the 44 grafts of 82%, 78%, and 78%, respectively, at 1, 2, and 3 years after atherectomy, and 86%, 83%, and 83% for the 67 individual stenoses treated. Directional atherectomy of vein graft stenoses has high technical and clinical success rates, acceptably low morbidity rates, and offers better sustained patency rates than balloon angioplasty. Its long-term patency rate seems to approach that of surgical vein patch angioplasty.