Early outcome of high energy Laser (Excimer) facilitated coronary angioplasty ON hARD and complex calcified and balloOn-resistant coronary lesions: LEONARDO Study.

AIM: An innovative xenon-chlorine (excimer) pulsed laser catheter (ELCA X80) has been recently used for the treatment of complex coronary lesions, as calcified stenosis, chronic total occlusions and non-compliant plaques. Such complex lesions are difficult to adequately treat with balloon angioplasty and/or intracoronary stenting. The aim of this study was to examine the acute outcome of this approach on a cohort of patients with coronary lesions. METHODS AND RESULTS: Eighty patients with 100 lesions were enrolled through four centers, and excimer laser coronary angioplasty was performed on 96 lesions (96%). Safety and effectiveness data were compared between patients treated with standard laser therapy and those treated with increased laser therapy. Laser success was obtained in 90 lesions (93.7%), procedural success was reached in 88 lesions (91.7%), and clinical success in was obtained in 87 lesions (90.6%). There was no perforation, major side branch occlusion, spasm, no-reflow phenomenon, dissection nor acute vessel closure. Increased laser parameters were used successfully for 49 resistant lesions without complications. CONCLUSIONS: This study suggests that laser-facilitated coronary angioplasty is a simple, safe and effective device for the management of complex coronary lesions. Furthermore, higher laser energy levels delivered by this catheter improved the device performance without increasing complications.

Effects of successful percutaneous lower extremity revascularization on cardiovascular outcome in patients with peripheral arterial disease.

BACKGROUND: Lower extremity peripheral arterial disease (LE-PAD) reduces walking capacity and is associated with an increased cardiovascular risk. Endovascular revascularization of LE-PAD improves walking performance and quality of life. In the present study, we determined whether successful lower limbs revascularization also impacts cardiovascular outcome in LE-PAD patients. METHODS: 479 consecutive LE-PAD patients at stage II of Fontaine's classification, with ankle/brachial index ≤ 0.90 and one or more stenosis >50% in at least one leg artery, were enrolled in the study. According to the Trans-Atlantic Inter Society Consensus II recommendations, 264 (55.1%) underwent percutaneous lower extremity angioplasty (PTA group), while 215 (44.9%) were managed with conservative therapy (MT group). The incidence of major cardiovascular events (including cardiovascular death, myocardial infarction, ischemic stroke, coronary and carotid revascularizations) was prospectively analyzed by Kaplan-Meier curves. Crude and adjusted HRs (95% CI) of developing a cardiovascular event were calculated by Cox analysis. RESULTS: No baseline differences were observed among the groups, except for a lower maximum walking distance in the PTA group. During a median follow-up of 21 months (12.0-29.0), the incidence of cardiovascular events was markedly lower in PTA compared to MT patients (6.4% vs. 16.3%; p=0.003), and patients in the MT group showed a 4.1-fold increased cardiovascular risk compared to patients in the PTA group, after adjustment for potential confounders (95% CI 1.22-13.57, p=0.023). CONCLUSIONS: This study shows that successful revascularization of LE-PAD patients affected by intermittent claudication, in addition to improving functional status, reduces the occurrence of future major cardiovascular events.

Endovascular treatment of lower extremity arteries is associated with an improved outcome in diabetic patients affected by intermittent claudication.

BACKGROUND: Lower extremity peripheral arterial disease (LE-PAD) is a highly prevalent condition among diabetic patients, associated with reduced walking capacity and a high incidence of cardiovascular events. Endovascular revascularization of lower extremities arteries improves walking performance and quality of life of diabetic patients affected by intermittent claudication, but few studies evaluated the impact of revascularization on cardiovascular outcome in this high-risk population. Accordingly, in the present study we evaluated if leg-ischemia resolution by effective lower limbs percutaneous revascularization can also impact cardiovascular outcome in a homogeneous group of diabetic patients affected by intermittent claudication. METHODS: 236 diabetic patients affected by LE-PAD at stage II of Fontaine's classification, with ankle/brachial index ≤ 0.90 and one or more hemodynamically significant stenosis in at least one artery of the ileo-femoro-popliteal axis were enrolled in the study. According to the Trans-Atlantic Inter Society Consensus II recommendations, 123 (52.1%) underwent percutaneous transluminal angioplasty (PTA group), while 113 (47.9%) underwent conservative medical therapy only (MT group). The incidence of major cardiovascular events (cardiovascular death, myocardial infarction, ischemic stroke, coronary or carotid revascularization) was prospectively analyzed with Kaplan-Meier curves and the risk of developing a cardiovascular event calculated by Cox analyses. RESULTS: No baseline difference in cardiovascular risk factors were observed between the PTA and MT groups, except for a lower prevalence of males in PTA group (74.8% vs. 85.8%, p=0.034). Furthermore, patients in the PTA group showed a worse walking capacity as expressed by maximum walking distance (108.7 ± 300.9 vs 378.4 ± 552.3 meters, p<0.001). During a median follow-up of 20 months (12.0-29.0), the incidence of cardiovascular events was markedly lower in patients in the PTA group with respect to patients in the MT group (7.3% vs. 22.1%, p=0.001), and patients of the MT group had at Cox analysis a 3.9 increased risk with respect to PTA group, after adjustment for potential confounding factors (95% CI 1.1-15.3, p=0.049). CONCLUSIONS: The present study shows that lower limbs revascularization of diabetic patients affected by intermittent claudication, in addition to improve walking performance, is associated with a reduction in the incidence of future major cardiovascular events.

Femoral plaque echogenicity and cardiovascular risk in claudicants.

OBJECTIVES: The present study was designed to verify whether the evaluation of femoral plaque echogenicity might be a useful tool for cardiovascular risk assessment in patients affected by lower extremity peripheral arterial disease. BACKGROUND: Lower extremity peripheral arterial disease is a common manifestation of atherosclerosis and is associated with a high risk of developing major cardiovascular events. Vulnerable atherosclerotic plaque plays a central role in the occurrence of acute ischemic events in different vascular territories. Furthermore, atherosclerosis is a systemic disease, and the presence of an unstable atherosclerotic plaque in a certain vascular district, characterized by low echogenicity at B-mode ultrasound, is associated to a greater prevalence of unstable plaques in other vascular beds. METHODS: Femoral plaque echogenicity of 246 claudicants with ankle/brachial index ≤0.90 was evaluated at B-mode ultrasound by visual analysis and by calculating the grayscale median (GSM) value. In these patients, the occurrence of myocardial infarction and stroke was prospectively assessed. RESULTS: Femoral GSM values and plaque types assessed by visual analysis were highly correlated by Spearman analysis (rho = 0.905, p < 0.001). During a median follow-up of 30 months, 32 patients (13%) had a major cardiovascular event. Compared with patients without events, those who experienced an event during the follow-up had a lower femoral plaque GSM value (42.9 ± 26.2 vs. 58.8 ± 19.3, p = 0.002) and a higher prevalence of hypoechoic femoral plaque at visual analysis (68.8% vs. 19.6%, p < 0.001). At Cox analysis, femoral GSM showed an inverse relationship with cardiovascular risk, even after adjustment for possible confounders (hazard ratio: 0.96, 95% confidence interval [CI]: 0.95 to 0.98, p < 0.001). Furthermore, patients with hypoechoic femoral plaques at visual analysis had a 7.24-fold increased cardiovascular risk compared with patients with hyperechoic plaques after adjustment for possible confounders (95% CI: 3.23 to 16.22, p < 0.001). CONCLUSIONS: This study demonstrates that the presence of hypoechoic atherosclerotic femoral plaques is associated with higher cardiovascular risk in lower extremity peripheral arterial disease patients.

Aortic valve sclerosis in patients with peripheral and/or coronary arterial disease.

BACKGROUND: Aortic valve sclerosis (AVS) is a marker of cardiovascular risk; its prevalence increases in elderly and in patients with hypertension and/or coronary arterial disease (CAD). There are no data available in patients with peripheral arterial disease (PAD) and with both CAD and PAD. METHODS: To investigate the presence of AVS, 57 patients with stable CAD, 38 with PAD, and 62 with CAD + PAD where studied by echocardiography. RESULTS: The prevalence of AVS progressively increased within groups (P = 0.005). The prevalence of AVS in PAD doubled that in CAD group (42.1% vs. 22.8%, P < 0.05). PAD patients had a 4.634 (95% CI: 1.02-17.88; P = 0.026) fold increased risk of AVS compared to CAD. Also CAD + PAD group had a higher prevalence of aortic sclerosis when compared to CAD group (50.8% vs. 22.8%, P = 0.001). CAD + PAD showed a 3.799 (95% CI: 1.26-11.45; P < 0 .01) fold greater risk of aortic sclerosis than CAD group. There were no differences in AVS prevalence between CAD + PAD and PAD group (50.8% vs. 42.1%; P = 0.36). Age was related to AVS in both analysis (PAD vs. CAD and CAD + PAD vs. CAD: OR = 1.09, 95% CI: 1.02-1.16, P = 0.011 and OR = 1.13, 95% CI: 1.07-1.21; P < 0.001) but no classical cardiovascular risk factors. CONCLUSIONS: PAD patients have an elevated prevalence of AVS greater than CAD patients. In patients with both disease, the prevalence of AVS is similar to that of patients with PAD alone.

Leukocyte count in peripheral arterial disease: A simple, reliable, inexpensive approach to cardiovascular risk prediction.

BACKGROUND: An elevated leukocyte count is widely proven to predict cardiovascular risk in healthy subjects and coronary patients, but its prognostic role in peripheral arterial disease (PAD) has received scarce attention. OBJECTIVES: To assess the impact of leukocyte count on the incidence of major cardiovascular events in PAD, and verify whether it adds to the prognostic power of the ankle/brachial index (ABI). METHODS: The occurrence of myocardial infarction and stroke was prospectively assessed in 259 consecutive PAD patients. Receiver-operating characteristic analysis and the bootstrap approach were used to identify the best cut-offs to predict the outcome, and hazard ratios (HRs) and c-statistics to assess the ability to classify risk. RESULTS: During a median follow-up of 30.0 months, 28 patients had an event. Adjusted Cox analyses performed on total and differential leukocyte counts, showed that only total leukocyte count (TLC) and neutrophil count (NC), considered as continuous variables, were associated with increased cardiovascular risk (HR=1.35, p<0.01 and HR=1.31, p<0.02, respectively). Patients with ABI < or = 0.63 plus TLC>7.7 x10(9)/L or NC>4.6 x 10(9)/L had a higher risk of about 5-fold vs patients with ABI>0.63 plus TLC< or =7.7 x 10(9)/L (p<0.01) or NC < or = 4.6 x 10(9)/L (p<0.01). The c-statistic for ABI was 0.61, similar to those for TLC (0.63) and NC (0.66). However, it significantly increased to 0.70 and 0.69 for the models incorporating ABI and TLC or ABI and NC, respectively (p<0.05 for both vs ABI alone). CONCLUSIONS: TLC and NC, which are inexpensive and reliable tests, predict major cardiovascular events in PAD, and add to the prognostic power of ABI, currently the most powerful prognostic indicator in these patients.

Concomitant coronary and peripheral arterial disease: relationship between the inflammatory status of the affected limb and the severity of coronary artery disease.

OBJECTIVE: In coronary artery disease (CAD), concomitant peripheral arterial disease (PAD) entails increased systemic inflammatory profile and more severe coronary atherosclerosis. We investigated the relationship between the inflammatory status in the affected limb and CAD severity. METHODS: In 46 CAD+PAD and 31 CAD-alone patients, the inflammatory status of the leg circulation was measured by the transfemoral gradients of neutrophil myeloperoxidase (MPOx) content and interleukin-6 (IL-6). CAD severity was defined by evaluating coronary artery endothelial function, number of significant coronary stenoses, and prevalence of three-vessel CAD and myocardial infarction (MI). RESULTS: In the affected limb of CAD+PAD patients, the transfemoral gradients of neutrophil MPOx content and IL-6 were higher (P < .01, for both) than in the healthy leg of CAD-only patients. At multivariate analysis, CAD+PAD patients with transfemoral gradients of MPOx and IL-6 > median had a more compromised coronary artery endothelial function (P < .05, for both). Furthermore, CAD+PAD patients with transfemoral gradients of neutrophil MPOx content > median showed an independent association with a greater number of significant coronary stenoses, and a greater prevalence of three-vessel CAD and previous MI (P < .01, for all). A more severe coronary atherosclerosis was observed also in CAD+PAD patients with transfemoral gradients of IL-6 > median vs those with IL-6 < median, although differences were not statistically significant. CONCLUSION: In CAD patients, the coexistence of PAD does not necessarily entail a more severe coronary atherosclerosis. Only those with an inflammatory status of the affected limb presents more severe CAD. Future studies will clarify whether the presence of peripheral inflammation plays a mechanistic role in CAD evolution.

IGF system and peripheral arterial disease: relationship with disease severity and inflammatory status of the affected limb.

OBJECTIVES: IGF-1 and its binding proteins are involved in the pathogenesis of atherosclerosis. We designed this study to unravel the relationship of the IGF system with peripheral arterial disease (PAD). DESIGN: Case-control, cross-sectional study. MEASUREMENTS: Serum levels of IGF-1, IGFBP-3 and acid labile subunit (ALS) were measured in 96 PAD patients and 89 controls. In 28 patients who underwent peripheral angiography, C-reactive protein (CRP), IGF-1, IGFBP-3 and ALS were measured in blood from femoral vein of the affected limb and aorta. RESULTS: Compared to controls, PAD patients showed lower levels of IGFBP-3 (3569 +/- 115 vs. 3106 +/- 107 microg/l, P < 0.01), and ALS (12.2 +/- 0.5 vs. 8.3 +/- 0.5 mg/l, P < 0.01). In PAD, concentrations of IGFBP-3 and ALS were significantly lower in patients with ankle/brachial index less than median than in those with a less severe PAD. In the affected limb, CRP venous-arterial difference correlated negatively with that of IGF-1 (rho = -0.57, P < 0.01), and positively with that of IGFBP-3 (rho = 0.63, P < 0.01). At multivariate analysis, a high transfemoral gradient of CRP was independently associated with a low transfemoral gradient of IGF-1 (beta coefficient = -0.48, P < 0.01), and a high transfemoral gradient of IGFBP-3 (beta coefficient = 0.22, P < 0.05). CONCLUSIONS: This study is the first to demonstrate that the systemic levels of IGF axis components are associated with the presence and severity of PAD, and that the inflammatory status of the ischaemic limb affects the transfemoral concentrations of IGF-1 and IGFBP-3. Due to the importance of IGF axis in modulating atherosclerotic plaque progression, our data may contribute to a better understanding of PAD pathophysiology.

In concomitant coronary and peripheral arterial disease, inflammation of the affected limbs predicts coronary artery endothelial dysfunction.

BACKGROUND: In coronary artery disease (CAD), concomitant peripheral arterial disease (PAD) entails more severe coronary atherosclerosis. We investigated whether the inflammatory status of affected limbs impairs coronary artery endothelial function (CAEF). METHODS: We measured the neutrophil myeloperoxidase content (NMPOxC) and plasma levels of interleukin-6 and C-reactive protein in the aorta, femoral vein, and coronary sinus of 22 CAD+PAD and 18 CAD-alone patients. CAEF was assessed by the cold pressure test. Human coronary artery endothelial cells (HCAECs) were incubated with serum from the femoral vein and aorta of CAD+PAD patients to determine whether blood leaving the affected limb activates HCAECs. RESULTS: In CAD+PAD patients, NMPOxC was higher across the femoral circulation than across the coronary circulation (p<0.01); it was also higher than across healthy femoral circulation of CAD patients (p<0.01). These findings apply also to interleukin-6, but not to C-reactive protein. The transfemoral gradient of NMPOxC and interleukin-6 significantly correlated with CAEF. The NMPOxC/CAEF relationship was much greater after exercise (R=0.79, p<0.001), which increased neutrophil activation across the affected circulation. The post-exercise association remained significant after adjustment for potential confounders (p<0.01). Serum from the affected limb of CAD+PAD patients induced, in vitro, a significant release of MCP-1 from HCAECs versus serum from the aorta of the same patients (630 [550-740] vs. 547 [490-620]; p<0.05). CONCLUSIONS: In CAD+PAD, triggers from the affected circulation may activate the endothelium at distant sites. Thus, PAD, besides being a marker of cardiovascular risk, could exert a mechanistic function in CAD progression.

Omega-3 polyunsaturated fatty acid in peripheral arterial disease: effect on lipid pattern, disease severity, inflammation profile, and endothelial function.

BACKGROUND & AIMS: Peripheral arterial disease (PAD) is strongly associated with endothelial dysfunction and inflammation, which portend a high cardiovascular risk. Accordingly, we investigated the effects of omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation on endothelial function and inflammatory status in affected individuals. METHODS: PAD patients were randomly divided into two groups. In Group I (n=16) pre-enrollment therapy was not modified, while in Group II (n=16) n-3 PUFAs 1 g b.i.d. for 3 months were added to the previous treatment. Endothelial function was assessed by measuring plasma soluble thrombomodulin (sTM) and brachial artery flow-mediated dilation (FMD), and the inflammatory status by measuring high-sensitivity C-reactive protein and myeloperoxidase. RESULTS: In Group II, n-3 PUFAs reduced sTM levels from the median value of 33.0 ng/mL (interquartile range 16.7, 37.2) to 17.0 ng/mL (11.2, 33.7) (p=0.04), and improved FMD from 6.7% (3.7, 8.7) to 10.0% (6.2, 14.2) (p=0.02). Conversely, these markers did not change in Group I. After 3 months, the levels of inflammatory markers remained unmodified in both groups. CONCLUSIONS: In PAD, n-3 PUFAs induced a marked improvement in endothelial function. Conversely, they did not affect the inflammatory status. In future, large, prospective studies are needed to investigate whether n-3 PUFAs, by improving endothelial function, would reduce the incidence of ischemic events in a population at high risk.

Endothelial dysfunction: a key to the pathophysiology and natural history of peripheral arterial disease?

Dysfunctional endothelium plays a crucial role in all stages of atherosclerosis and thus the accurate assessment of this organ is a valuable tool, especially if such assessments are clinically relevant. In peripheral arterial disease (PAD), which affects about 27 million of individuals in Europe and North America, increased plasma markers of endothelial dysfunction and reduced endothelium-mediated vasoreactivity, are associated with both the severity and the extent of atherosclerosis in the arteries of the lower limbs, is exacerbated by acute exercise, may help identify subjects with subclinical coronary artery disease, and portends a worse outcome. As a result, endothelial dysfunction is a promising target for therapeutic interventions in PAD. Large clinical trials are needed to verify whether affected individuals with depressed endothelial function benefit from specific treatments.

Myeloperoxidase, but not C-reactive protein, predicts cardiovascular risk in peripheral arterial disease.

AIMS: The prognostic role of inflammation in peripheral arterial disease (PAD) remains to be conclusively established. Accordingly, in these patients we investigated the impact of myeloperoxidase (MPOx) and C-reactive protein on the incidence of myocardial infarction and stroke. METHODS AND RESULTS: Of 156 PAD patients, 10 had a myocardial infarction and seven a stroke, during follow-up. We used the receiver operating characteristic curve analysis and the bootstrap approach to identify the MPOx, C-reactive protein, and ankle brachial index (ABI) threshold levels that provided the best cut-off to predict the outcome. For MPOx a cut-off > or =183.7 pM was independently associated with a poor outcome (HR = 6.80, 95% CI 1.20-38.69, P = 0.031). The result remained unmodified when MPOx was used as a continuous variable (HR = 1.03, 95% CI 1.01-1.05, P = 0.031). Conversely, C-reactive protein was not a prognostic determinant in our series (HR = 0.88, 95% CI 0.60-1.29, P = 0.514). Kaplan-Meier curves for the four groups of patients delineated according to ABI and MPOx values identified using the bootstrap approach showed that the addition of MPOx measurement to ABI improved the ability to identify patients at risk for myocardial infarction and stroke. CONCLUSION: In PAD, MPOx, but not C-reactive protein, predicts an increased risk of major cardiovascular events, and adds to the prognostic value of ABI, currently the most powerful prognostic indicator in these patients.

Mortality in peripheral arterial disease: a comparison of patients managed by vascular specialists and general practitioners.

BACKGROUND: Peripheral arterial disease (PAD) is undertreated by general practitioners (GPs). However, the impact of the suboptimal clinical management is unknown. OBJECTIVE: To assess the mortality rate of PAD patients in relation to the type of physician who provides their care (GP or vascular specialist). DESIGN: Prospective study. SETTING: Primary care practice and academic vascular laboratory. PARTICIPANTS: GP patients (n = 60) were those of the Peripheral Arteriopathy and Cardiovascular Events study (PACE). Patients managed by specialists (n = 82) were consecutive subjects with established PAD who were referred to our vascular laboratory during the enrollment period of the PACE study. MEASUREMENTS: All-cause and cardiovascular mortality. RESULTS: After 32 months of follow-up, specialist management was associated with a lower rate of all-cause mortality (RR = 0.04; 95% CI 0.01-0.34; p = .003) and cardiovascular mortality (RR = 0.07; 95% CI 0.01-0.65; p = .020), after adjustment for patients' characteristics. Specialists were more likely to use antiplatelet agents (93% vs 73%, p < .001), statins (62% vs 25%, p < .001) and beta blockers (28% vs 3%, p < .001). Survival differences between specialists and GPs disappeared once the use of pharmacotherapies was added to the proportional hazard model. The fully adjusted model showed that the use of statins was significantly associated with a reduced risk of all-cause mortality (RR = 0.02; 95% CI 0.01-0.73, p = .034) and cardiovascular mortality (RR = 0.02; 95% CI 0.01-0.71, p = .033). CONCLUSIONS: Specialist management of patients with symptomatic PAD resulted in better survival than generalist management. This effect appears to be mainly caused by the more frequent use of effective medicines by specialists.

Peripheral arterial disease and cardiovascular risk in Italy. Results of the Peripheral Arteriopathy and Cardiovascular Events (PACE) study.

OBJECTIVE: Our knowledge about the natural history of peripheral arterial disease (PAD) is derived from studies carried out almost exclusively in northern European and northern American populations. This study was aimed at defining mortality and cardiovascular morbidity of PAD patients in Italy. METHODS: From the lists of seven general practitioners, we identified all subjects aged 40-80 years (n = 4352). Of those reporting leg symptoms while walking at the Rose Questionnaire (n = 760), 60 (1.6% of the general population) had PAD, as evidenced by an ankle-brachial index of < 0.90 or reduced Doppler flow velocity. For each PAD patient, three sex and age-matched controls negative to the Rose Questionnaire were randomly selected from the general practice lists. RESULTS: After 24 months of follow-up, 15% of PAD patients died, 8% from cardiovascular disease, and 25% developed a non-fatal cardiovascular event. At Cox analysis, the presence of PAD was associated with an increased risk of all-cause mortality (relative risk 4.03; 95% confidence interval 1.50-10.84; P = 0.006), cardiovascular mortality (relative risk 7.77; 95% confidence interval 1.51-40.16; P = 0.014), and non-fatal cardiovascular events (relative risk 3.11; 95% confidence interval 1.41-6.80; P = 0.005). CONCLUSIONS: This Italian study shows that, in general practice, symptomatic PAD is associated with a four-fold increased risk of mortality and a nearly eight-fold increased risk of cardiovascular mortality. These figures are quite similar to those reported in northern European and northern American populations. General practitioners, who are the clinicians primarily and largely responsible for the care of these patients, should be alerted to the consequences of PAD.

Metabolic syndrome in peripheral arterial disease: relationship with severity of peripheral circulatory insufficiency, inflammatory status, and cardiovascular comorbidity.

OBJECTIVE: Metabolic syndrome is defined by the clustering in the same person of at least three risk factors such as hyperglycemia, hypertriglyceridemia, low levels of high-density lipoprotein, hypertension, and abdominal obesity. In patients with peripheral arterial disease (PAD), we investigated the prevalence of metabolic syndrome and its relationship with the severity of peripheral circulatory insufficiency, inflammatory status, and cardiovascular comorbidity. METHODS: The presence of metabolic syndrome was assessed in 154 consecutive PAD patients (115 men, 39 women). Inflammatory status was assessed by measuring serum levels of C-reactive protein (CRP). RESULTS: Metabolic syndrome was present in 51.9% (42.7 % in men, 74.3% in women, P < .01). Patients with an ankle/brachial index (ABI) <0.64 (median) were more likely to have metabolic syndrome than those with less severe PAD (63.9% vs 42.8%, P < .02). The association between a low ABI and metabolic syndrome was maintained after adjustment for age and sex (odds ratio [OR], 2.19; 95% confidence interval [CI], 1.03 to 4.68). Compared with PAD patients without metabolic syndrome, those with the syndrome had greater body mass index (28.2 [25.6; 29.8] kg/m(2) vs 26.1 [24.2; 27.7] kg/m(2), P < .01) and higher levels of CRP (3.9 [1.6; 7.6] mg/L vs 2.0 [1.1; 3.7] mg/L, P < .02). A previous myocardial infarction was documented in 58.2% of patients with and in 37.5% of those without metabolic syndrome (P < .01). At multivariate analysis, metabolic syndrome was significantly associated with previous myocardial infarction also after adjustment for ABI (OR, 2.15; 95% CI, 1.06 to 4.38). CONCLUSIONS: Metabolic syndrome is present in >50% of PAD patients. The finding that well-established indicators of increased cardiovascular risk such as low ABI and increased CRP levels cluster with metabolic syndrome suggests that identification of this syndrome in these high-risk patients could indicate an even greater risk of cardiovascular events.

Cellular adhesion molecules and peripheral arterial disease.

Cellular adhesion molecules (CAMs), by mediating the recruitment of circulating leukocytes to the blood vessel wall and their subsequent migration into the subendothelial spaces, play a crucial role in all stages of atherosclerosis. Soluble forms of CAMs, probably derived from proteolytic shedding, are present in the circulation and their blood levels parallel the amount expressed on the cell surface. In patients with peripheral arterial disease (PAD), increased levels of soluble CAMs have been found during exercise-induced claudication, are associated with the presence, the severity and the extent of atherosclerosis in the arteries of the lower limbs, and portend a worse outcome. These findings have provided new insights into the pathophysiology of PAD and its consequences. However, further large population studies are needed to firmly establish whether increased levels of circulating CAMs give additive information to current risk assessment approaches, and to verify whether PAD patients with elevated levels of circulating CAMs would benefit from any specific therapy.

Effect of propionylcarnitine on changes in endothelial function and plasma levels of adhesion molecules induced by acute exercise in patients with intermittent claudication.

In patients with intermittent claudication, treadmill exercise may cause acute deterioration of endothelial function and increase in plasma concentrations of adhesion molecules. The authors evaluated the efficacy of intravenously administered propionylcarnitine (PLC)in preventing these phenomena. Thirty-six claudicants with postexercise decrease in brachial artery flow-mediated dilation (FMD)were randomized to either placebo or PLC (600 mg as a single bolus followed by 1 mg/kg/min for 60 minutes).In the 18 patients randomized to placebo, FMD markedly decreased with exercise before (from 6.8 +/-0.4% to 4.0 +/-0.4%; p < 0.001) and after treatment (from 6.5 +/-0.4% to 4.4 +/-0.5%; p < 0.001). By contrast, in the PLC group, FMD significantly decreased with exercise before treatment (from 8.0 +/-0.7% to 4.4 +/-0.4%; p < 0.001), but not after active drug administration (from 7.1 +/-0.7% to 6.0 +/-0.6%; p = 0.067). The difference between treatments was not significant (p = 0.099; ANOVA). However, in the PLC group, the authors found that the greater the exercise-induced deterioration in endothelial function before treatment, the greater the capacity of PLC to prevent a postexercise decrease in FMD (r = -0.50, p = 0.034). Accordingly, they analyzed data in the 19 patients with a baseline exercise-induced decrease in FMD >or=45% (ie, the median FMD reduction in the entire group of 36 patients), and found that the exercise-induced FMD decrease was less after PLC than after placebo (p = 0.046, ANOVA). In the same subgroup, the exercise-induced increase in plasma concentrations of soluble vascular cell adhesion molecule-1 (sVCAM-1) was significantly higher before than after treatment in patients randomized to PLC (23.4 +/-5% vs 15.3 +/-7%, p = 0.007). In conclusion, in patients with intermittent claudication suffering from a greater endothelial derangement after treadmill, PLC administration provided a protective effect against deterioration of FMD and increase of sVCAM-1 induced by exercise.

Functional status measured by walking impairment questionnaire and cardiovascular risk prediction in peripheral arterial disease: results of the Peripheral Arteriopathy and Cardiovascular Events (PACE) study.

The prognostic impact of the functional status of patients with intermittent claudication is still obscure. From the lists of seven general practitioners, we identified all subjects aged 40-80 years (n = 4352). Of those reporting leg symptoms while walking on the Rose questionnaire (n = 760), 60 had a qualifying diagnosis of peripheral arterial disease (PAD). All of them received the Walking Impairment Questionnaire (WIQ). For each patient affected by PAD, three sex- and age-matched controls were selected randomly. After a 24-month follow-up, survival curves showed that PAD patients with WIQ scores > median had a higher cardiovascular risk than controls, and patients with WIQ scores < median had an even poorer prognosis (p < 0.001 for all WIQ domains). In PAD, after adjustment for age, sex, ankle-brachial index and comorbidity, two WIQ domains (ie walking speed and stair-climbing) were associated with cardiovascular events. The cardiovascular risk of claudicants who had a score > median for at least three WIQ domains was intermediate versus the risk of controls and PAD patients with a WIQ score < median, also when adjusted for the covariates indicated above (RR = 3.26, p = 0.019). In intermittent claudication, a worse functional status entails a greater risk of ischemic events versus low functional impairment.

Adhesion molecules and cardiovascular risk in peripheral arterial disease. Soluble vascular cell adhesion molecule-1 improves risk stratification.

Although intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) play a relevant role in atherosclerosis, little is known about the prognostic impact of their soluble forms (s) in patients with peripheral arterial disease (PAD). The aim of this prospective study was to verify whether plasma levels of sICAM-1 and sVCAM-1 predict cardiovascular risk in PAD, and improve the prognostic value of the ankle/brachial index (ABI) alone. Accordingly, plasma levels of sICAM-1 and sVCAM-1, and the ABI were measured in 75 PAD patients who were monitored for a mean of 24+/-13 months. Twenty-two (29.3%) patients had a cardiovascular event (15 coronary, 3 cerebrovascular and 4 peripheral events). Plasma levels of sVCAM-1 were 618+/-258 ng/mL in patients with and 496+/-164 ng/mL in those without an event (p=0.016). The corresponding sICAM-1 values were 344+/-239 ng/mL and 275+/-99 ng/mL (p=0.079). The cardiovascular event rate was higher in patients with sVCAM-1 levels above the median than in those with sVCAM-1 below the median (p=0.0027 by log rank test). Independent predictors of events were sVCAM-1 levels above the median (p=0.005) and an ABI below the median (p=0.001). Amongst patients with ABI below the median, the occurrence of sVCAM-1 above the median was associated with a 3.4-fold increase in risk (95% CI 1.308 to 9.573, p=0.013). In conclusion, increased plasma levels of sVCAM-1 have a negative prognostic impact in PAD and improve the predictive value of ABI, which is currently the most powerful risk indicator in these patients.

Endothelial dysfunction and cardiovascular risk prediction in peripheral arterial disease: additive value of flow-mediated dilation to ankle-brachial pressure index.

BACKGROUND: Endothelial dysfunction plays a key role in atherogenesis. We prospectively investigated the impact of noninvasive measurement of endothelial function on cardiovascular risk in peripheral arterial disease (PAD). The study was specially aimed at assessing whether brachial artery flow-mediated dilation (FMD) added to the predictive value of ankle-brachial pressure index (ABPI). METHODS AND RESULTS: Of 131 patients monitored for a mean of 23+/-10 months, 18 had a coronary event, 12 a cerebrovascular event, and 9 a peripheral event. The median FMD was lower in patients with an event than in those without (5.8% versus 7.6%, P<0.05), whereas vasodilation to nitroglycerin was similar in the two groups. The cardiovascular event rate was higher in patients with FMD below the median versus those with FMD above the median (P<0.001 by log-rank test). In a Cox proportion hazard model, independent predictors of events were FMD below the median (P<0.01), ABPI below the median (P<0.01), and previous stroke (P<0.02). Similar results were obtained when peripheral events were excluded from the analysis. Below-median ABPI and FMD combined was more accurate in predicting risk (relative risk [RR] 13.0; 95% CI, 3.0 to 56.2; P<0.01) than ABPI (RR, 6.4; 95% CI, 1.4 to 29.1; P<0.02) and FMD (RR, 4.8; 95% CI, 1.1 to 23.3; P<0.05) alone. CONCLUSIONS: A low brachial artery FMD is an independent predictor of cardiovascular risk in patients with PAD and adds to the prognostic value of ABPI, which is currently the most powerful prognostic indicator in PAD.