The use of arm vein in lower-extremity revascularization: results of 520 procedures performed in eight years.

PURPOSE: The absence of an adequate ipsilateral saphenous vein in patients requiring lower-extremity revascularization poses a difficult clinical dilemma. This study examined the results of the use of autogenous arm vein bypass grafts in these patients. METHODS: Five hundred twenty lower-extremity revascularization procedures performed between 1990 and 1998 were followed prospectively with a computerized vascular registry. The arm vein conduit was prepared by using intraoperative angioscopy for valve lysis and identification of luminal abnormalities in 44.8% of cases. RESULTS: Seventy-two (13. 8%) femoropopliteal, 174 (33.5%) femorotibial, 29 (5.6%) femoropedal, 101 (19.4%) popliteo-tibial/pedal, and 144 (27.7%) extension "jump" graft bypass procedures were performed for limb salvage (98.2%) or disabling claudication (1.8%). The average age of patients was 68.5 years (range, 32 to 91 years); 63.1% of patients were men, and 36.9% of patients were women. Eighty-five percent of patients had diabetes mellitus, and 77% of patients had a recent history of smoking. The grafts were composed of a single arm vein segment in 363 cases (69. 8%) and of spliced composite vein with venovenostomy in 157 cases (30.2%). The mean follow-up period was 24.9 months (range, 1 month to 7.4 years). Overall patency and limb salvage rates for all graft types were: primary patency, 30-day = 97.0% +/- 0.7%, 1-year = 80.2% +/- 2.1%, 3-year = 68.9% +/- 3.6%, 5-year = 54.5% +/- 6.6%; secondary patency, 30-day = 97.0% +/- 0.7%, 1-year = 80.7% +/- 2.1%, 3-year = 70.3% +/- 3.4%, 5-year = 57.5% +/- 6.2%; limb salvage, 30-day = 97.6% +/- 0.7%, 1-year = 89.8% +/- 1.7%, 3-year = 82.1% +/- 3.3%, 5-year = 71.5% +/- 6.9%. Secondary patency and limb salvage rates were greatest at 5 years for femoropopliteal grafts (69.8% +/- 12.8%, 80.7% +/- 11.8%), as compared with femorotibial (59.6% +/- 10. 3%, 72.7% +/- 10.5%), femoropedal (54.9% +/- 25.7%, 56.8% +/- 26.9%, ) and popliteo-tibial/pedal grafts (39.0% +/- 7.3%, 47.6% +/- 15.4%). The patency rate of composite vein grafts was equal to that of single-vein conduits. The overall survival rate was 54% at 4 years. CONCLUSION: Autogenous arm vein has been used successfully in a wide variety of lower-extremity revascularization procedures and has achieved excellent long- and short-term patency and limb salvage rates, higher than those generally reported for prosthetic or cryopreserved grafts. Its durability and easy accessibility make it an alternative conduit of choice when an adequate saphenous vein is not available.

Soluble intercellular adhesion molecule, vascular cell adhesion molecule, and impaired microvascular reactivity are early markers of vasculopathy in type 2 diabetic individuals without microalbuminuria.

OBJECTIVE: Using von Willebrand Factor (vWF) as a marker of endothelial function, previous studies have shown that the development of microalbuminuria is associated with the onset of endothelial dysfunction in individuals with type 2 diabetes. We tested the hypothesis that endothelial dysfunction is already evident in normoalbuminuric individuals with type 2 diabetes. RESEARCH DESIGN AND METHODS: We used laser Doppler imaging scanning to measure vasodilation in the forearm skin in response to iontophoresis of 1% acetylcholine (endothelium-dependent) and 1% sodium nitroprusside (endothelium-independent). Multiple indicators of endothelial function--soluble intercellular adhesion molecule (sICAM), soluble vascular cell adhesion molecule (sVCAM), vWF, and microvascular reactivity--were measured in 20 healthy control subjects, 45 normoalbuminuric (urinary albumin/creatinine ratio < 30 micrograms/mg) individuals with type 2 diabetes, and 14 microalbuminuric (urinary albumin/creatinine ratio between 30 and 300 micrograms/mg) individuals with type 2 diabetes. RESULTS: Serum sICAM and sVCAM levels were elevated in the normoalbuminuric (305 +/- 120, 851 +/- 284 ng/ml) and microalbuminuric (300 +/- 89, 845 +/- 252 ng/ml) individuals with diabetes when compared with the healthy control subjects (213 +/- 58, 661 +/- 176 ng/ml) (P < 0.01). Furthermore, the microvascular endothelium-dependent and -independent vasodilation was reduced in the normoalbuminuric (76 +/- 44, 70 +/- 33) (percent increase in perfusion over baseline) and microalbuminuric (74 +/- 41, 73 +/- 28) individuals with diabetes compared with healthy control subjects (126 +/- 67, 120 +/- 47) (P < 0.05). In contrast, plasma vWF was elevated only in the microalbuminuric individuals with diabetes (129 +/- 35%) compared with the normoalbuminuric individuals with diabetes (110 +/- 34) and healthy control subjects (111.3 +/- 39) (P < 0.05). On stepwise multivariate analysis, fasting blood glucose was the most important contributing factor to the variation in microvascular reactivity and sVCAM, whereas insulin resistance (by homeostasis model assessment) was the most important contributing factor to the variation in sICAM. Addition of all clinical and biochemical measures explained only 15-22% of the variation in sICAM, sVCAM, and microvascular reactivity. CONCLUSIONS: Multiple markers of endothelial dysfunction were evident in normoalbuminuric individuals with type 2 diabetes. The pathogenic process of vasculopathy in type 2 diabetes occurs early and may be operative before the development of microalbuminuria.

The effect of hormonal replacement therapy on the vascular reactivity and endothelial function of healthy individuals and individuals with type 2 diabetes.

Estrogens protect healthy women from cardiovascular disease. However, epidemiological data suggest that women with diabetes are denied the cardioprotection associated with estrogens. Whether or not hormonal replacement therapy (HRT) confers cardiovascular benefits in postmenopausal women with diabetes is not known. The aim of this study was to examine the effects of HRT on the microvascular reactivity and endothelial function of individuals with and without diabetes. We studied the following groups of individuals: premenopausal healthy women [n = 28, age 41 +/- 8 yr (mean +/- SD)], premenopausal women with type 2 diabetes (n = 16, age 43 +/- 6 yr); postmenopausal healthy women (n = 12, age 57 +/- 4 yr), postmenopausal women with diabetes (n = 17, age 62 +/- 5 yr); postmenopausal healthy women on HRT (n = 13, age 51 +/- 5 yr), postmenopausal women with diabetes on HRT (n = 11, age 57 +/- 7 yr). We used laser Doppler flowmetry to measure forearm cutaneous vasodilatation in response to iontophoresis of 1% acetylcholine (endothelium dependent) and 1% sodium nitroprusside (endothelium independent). The endothelium-dependent vasodilation was significantly higher in premenopausal healthy women (180 +/- 67%; increase over baseline) compared to premenopausal diabetic women (87 +/- 41%; P < 0.001). endothelium-dependent vasodilation was also higher in postmenopausal healthy women on HRT (143 +/- 52) compared with postmenopausal diabetic women on HRT (86 +/- 61), postmenopausal healthy women without HRT (104 +/- 43), and postmenopausal diabetic women without HRT (74 +/- 28; P < 0.001). A similar pattern of responses was observed in the endothelium-independent vasodilation (premenopausal healthy women, 126 +/- 56; premenopausal diabetic women, 88 +/- 26; postmenopausal healthy women on HRT, 121 +/- 37; postmenopausal diabetic women on HRT, 88 +/- 41; postmenopausal healthy women without HRT, 84 +/- 36; and postmenopausal diabetic women without HRT, 73 +/- 36; P < 0.001). Soluble intercellular adhesion molecule (sICAM) was also measured among all the women with diabetes. Premenopausal women with diabetes (248.9 +/- 56 ng/ml) and postmenopausal women with diabetes on HRT (257.7 +/- 49 ng/ml) had lower sICAM levels compared with the postmenopausal diabetic women without HRT (346.4 +/- 149 ng/ml; P < 0.05). We conclude that menopausal status and type 2 diabetes are associated with impaired microvascular reactivity. HRT substantially improves microvascular reactivity in postmenopausal healthy women. In contrast, the effect of HRT on the microvascular reactivity of postmenopausal diabetic women is less apparent. However, the use of HRT among women with diabetes is associated with lower sICAM levels, suggesting an attenuation in endothelial activation.

Microvascular and macrovascular reactivity is reduced in subjects at risk for type 2 diabetes.

Abnormalities in vascular reactivity in the micro- and macrocirculation are well established in type 2 diabetes. However, little is known about changes in vascular reactivity in those at risk for developing type 2 diabetes. To address this situation, the vascular reactivity in both the micro- and macrocirculation was studied in four age and sex comparable groups: 30 healthy normoglycemic subjects with no history of type 2 diabetes in a first-degree relative (controls), 39 healthy normoglycemic subjects with a history of type 2 diabetes in one or both parents (relatives), 32 subjects with impaired glucose tolerance (IGT), and 42 patients with type 2 diabetes without vascular complications (diabetes). Laser Doppler perfusion imaging was used to measure vasodilation in the forearm skin in response to iontophoresis of 1% acetylcholine chloride (Ach) (endothelium-dependent) and 1% sodium nitroprusside (SNP) (endothelium-independent), whereas high-resolution ultrasound images were used to measure brachial artery diameter changes during reactive hyperemia. Plasma concentrations of endothelin-1 (ET-1), von Willebrand factor (vWF), soluble intercellular adhesion molecule (sICAM), and soluble vascular cell adhesion molecule (sVCAM) were also measured as indicators of endothelial cell activation. The vasodilatory responses to Ach, expressed as percent increase of blood flow over baseline, were reduced in relatives (98 +/- 48, mean +/- SD), IGT (94 +/- 52), and diabetes (74 +/- 45) compared with controls (126 +/- 67) (P < 0.001 controls versus relatives, IGT, and diabetes). The responses to SNP were similarly reduced: controls (123 +/- 46), relatives (85 +/- 46), IGT (83 +/- 48), and diabetes (65 +/- 31) (P < 0.001 controls versus relatives, IGT, and diabetes) as were the responses in the brachial artery diameter during reactive hyperemia: controls (13.7 +/- 6.1), relatives (10.5 +/- 6.7), IGT (9.8 +/- 4.5), and diabetes (8.4 +/- 5.0) (P < 0.01 controls versus relatives, IGT, and diabetes). Women had greater responses than men in both the micro- and macrovascular circulatory tests, but a similar progressive reduction was observed in both sexes with increasing degrees of glucose intolerance. A significant inverse correlation was found between microvascular reactivity and systolic blood pressure, fasting plasma glucose, HDL cholesterol, fasting plasma insulin, and homeostasis model assessment (HOMA) values, an index of insulin resistance. BMI and diastolic blood pressure had a significant inverse correlation only with endothelium-dependent vasodilation. In the macrocirculation, systolic blood pressure, HbA1c, HDL cholesterol, and HOMA had significant correlation with brachial artery diameter changes. Compared with control subjects, ET-1 was significantly higher in all groups, vWF was higher only in the diabetic group, sICAM levels were higher in the IGT and diabetic groups, while sVCAM concentrations were higher in the relatives and those with diabetes (P < 0.05). On stepwise multivariate analysis, age, sex, fasting plasma glucose, and BMI were the most important contributing factors to the variation of vascular reactivity. Addition of all clinical and biochemical measures explained only 32-37% of the variation in vascular reactivity. These results suggest that abnormalities in vascular reactivity and biochemical markers of endothelial cell activation are present early in individuals at risk of developing type 2 diabetes, even at a stage when normal glucose tolerance exists, and that factors in addition to insulin resistance may be operative.

Lower extremity arterial reconstruction in the very elderly: successful outcome preserves not only the limb but also residential status and ambulatory function.

PURPOSE: The purpose of this study was to evaluate our results with lower extremity arterial reconstruction (LEAR) in patients 80 years of age or older and to assess its impact on ambulatory function and residential status. METHODS: We performed a retrospective review of all patients 80 years of age or older undergoing LEAR at a single institution from January 1990 through December 1995. Preoperative information regarding residential status and ambulatory function was obtained from the hospital record and vascular registry. Telephone interviews with patients or next of kin were undertaken to provide information regarding postoperative residential status and ambulatory function. Residential status and level of ambulatory function were graded by a simple scoring system in which 1 indicates living independently, walking without assistance; 2 indicate living at home with family, walking with an ambulatory assistance device; 3 indicates an extended stay in a rehabilitation facility, using a wheelchair; and 4 indicates permanent nursing home, bedridden. Preoperative and postoperative scores for both residential status and ambulatory function were compared. Kaplan-Meier survival curves were generated for graft patency, limb salvage, and patient survival. RESULTS: Two hundred ninety-nine lower extremity bypass operations were performed in 262 patients 80 years of age or older (45% men, mean age 83.6 years, range 80 to 96 years). Sixty-seven percent of the patients had diabetes mellitus. Limb salvage was the indication for operation in 96%. The preoperative mean residential status and ambulatory function scores were 1.79+/-0.65 and 1.55+/-0.66, respectively. The perioperative mortality rate at 30 days was 2.3%. The median length of hospital stay decreased from 16 days in 1990 to 8 days in 1995 (range 4 to 145 days). Eighty-seven percent of grafts were performed with the autologous vein. The 5-year primary, assisted primary, and secondary graft patency rates for all grafts were 72%, 80%, and 87%, respectively. The limb salvage rate at 5 years was 92%. The patient survival rate at 5 years was 44%. The postoperative residential status and ambulatory function scores were 1.95+/-0.80 and 1.70+/-0.66, respectively. Overall scores remained the same or improved in 88% and 78% of patients, respectively. CONCLUSION: LEAR in octogenarians is safe, with graft patency and limb salvage rates comparable to those reported for younger patients. LEAR preserves the ability to ambulate and reside at home for most patients.

Reactive hyperemic response of the brachial artery: comparison of proximal and distal occlusion.

RATIONALE AND OBJECTIVES: The authors compared the postocclusion hyperemic responses of the brachial artery after occluding blood flow proximal to and distal to the studied area. MATERIALS AND METHODS: Response of the brachial artery to hypoxia was evaluated with duplex Doppler ultrasound in 13 healthy subjects. A pneumatic tourniquet was first positioned 2-5 cm superior to the left elbow, proximal to the area of artery studied. Two hours later the response was remeasured with the tourniquet positioned 2-5 cm inferior to the elbow, distal to the artery studied. Arterial diameter, mean and peak flow velocities, and heart rate were assessed. RESULTS: No significant differences were observed between measurements of baseline and postischemic arterial diameter, percentage diameter change, baseline mean arterial blood flow velocity, baseline peak arterial blood flow velocity, or postischemic heart rate obtained with proximal occlusion of the artery and those obtained with distal occlusion. In contrast, mean and peak postischemic arterial blood flow velocity and preocclusion heart rate were higher in measurements made during proximal artery occlusion. Significant correlation was found between measurements of percentage change in artery diameter obtained with proximal artery occlusion and those obtained with distal occlusion (r = 0.611, P < .05). CONCLUSION: There are no major differences in postischemic changes in brachial artery diameter related to reactive hyperemia between blood flow occlusion applied proximal and distal to the studied area. However, there are significant differences in the mean and peak systolic velocities. Either occlusion site can be used for clinical studies if arterial diameter change is monitored, but if velocity measurements are being compared, a single occlusion site should be chosen.

Differences in foot and forearm skin microcirculation in diabetic patients with and without neuropathy.

OBJECTIVE: We have compared the hyperemic response to heat and the endothelium-dependent and endothelium-independent vasodilatation between the dorsum of the foot and the forearm in diabetic neuropathic and non-neuropathic patients and healthy control subjects. RESEARCH DESIGN AND METHODS: We studied the cutaneous microcirculation in the forearm and foot in 15 diabetic patients with neuropathy, in 14 diabetic patients without neuropathy, and in 15 control subjects matched for age, sex, BMI, and in the case of diabetic patients, for the duration of diabetes. Patients with peripheral vascular disease and/or renal impairment were excluded. The cutaneous microcirculation of the dorsum of the foot and the flexor aspect of the forearm was tested in all subjects. Single-point laser Doppler was employed to measure the maximal hyperemic response to heating of the skin to 44 degrees C and laser Doppler imaging scanner was used to evaluate the response to iontophoresis of 1% acetylcholine chloride (Ach) (endothelium-dependent response) and 1% sodium nitroprusside (NaNP) (endothelium-independent response). RESULTS: The transcutaneous oxygen tension was lower in the neuropathic group at both foot and forearm level, while the maximal hyperemic response to heat was similar at the foot and forearm level in all three groups. The endothelium-dependent vasodilation (percent increase over baseline) was lower in the foot compared to the forearm in the neuropathic group (23 +/- 4 vs. 55 +/- 10 [mean +/- SEM]; P < 0.01)], the non-neuropathic group (33 +/- 6 vs. 88 +/- 14; P < 0.01), and the control subjects (43 +/- 6 vs. 93 +/- 13; P < 0.001). Similar results were observed during the iontophoresis of NaNP (P < 0.05). No differences were found among the three groups when the ratio of the forearm:foot response was calculated for both the endothelium-dependent (neuropathic group, 2.25 +/- 0.24; non-neuropathic group, 2.55 +/- 0.35; and control subjects, 2.11 +/- 0.26; P = NS) and endothelium-independent vasodilation (neuropathic group, 1.54 +/- 0.27; non-neuropathic group, 2.08 +/- 0.33; and control subjects, 2.77 +/- 1.03; P = NS). The vasodilatory response, which is related to the C nociceptive fiber action, was reduced at the foot level during iontophoresis of Ach in the neuropathic group. In contrast, no difference was found during the iontophoresis of NaNP at the foot and forearm level and of Ach at the forearm level among all three groups. CONCLUSIONS: In healthy subjects, the endothelial-dependent and endothelial-independent vasodilatation is lower at the foot level when compared to the forearm, and a generalized impairment of the microcirculation in diabetic patients with neuropathy preserves this forearm-foot gradient. These changes may be a contributing factor for the early involvement of the foot with neuropathy when compared to the forearm.

Estrogen improves endothelial function.

PURPOSE: To determine the effect of estrogen on endothelium-dependent relaxation in the cutaneous microcirculation of women. METHODS: Three groups of women participated in the study. Group 1 (n = 20) was premenopausal and had a mean age of 39 years (range 24-50 years). Group 2 (n = 9) was postmenopausal and had a mean age of 58 years (range 53-65 years). Group 3 (n = 11) was postmenopausal and taking estrogen replacement therapy; the mean age was 53 years (range 43-58 years). Eleven women in group 1 underwent testing twice, once during menstruation (mean serum estradiol level 73 +/- 30 pg/ml) and once during midcycle (mean serum estradiol level 268 +/- 193 pg/ml; p = 0.003). Single-point laser Doppler ultrasound and laser Doppler imaging with a scanner were used to measure vasodilatation in the forearm skin in response to iontophoresis of 1% acetylcholine (endothelium dependent) and 1% sodium nitroprusside (endothelium-independent smooth muscle relaxant). RESULTS: All three groups were matched for body mass index and fasting glucose, total, high-density lipoprotein, and low-density lipoprotein cholesterol and triglyceride levels. All women had normal blood pressure, and none smoked. Mean serum estradiol levels were 196 +/- 170 pg/ml (group 1), 35 +/- 12 pg/ml (group 2), and 107 +/- 78 pg/ml (group 3) (p = 0.004). Maximum microvascular vasodilatation (percentage increase over baseline) in response to acetylcholine was reduced in group 2 (93% +/- 43%) compared with group 1 (187% +/- 63%) and group 3 (142% +/- 56%) (p = 0.001). The response to sodium nitroprusside also was diminished in group 2 (73% +/- 27%) compared with group 1 (126% +/- 45%) and group 3 (100% +/- 32%) (p = 0.02). Within group 1 the acetylcholine response was higher during the midcycle phase (186% +/- 31%) compared with the menstrual phase (147% +/- 57%) (p < 0.05). The sodium nitroprusside response also was higher during the midcycle phase (144% +/- 31%) compared with the menstrual phase (94% +/- 41%) (p < 0.05) CONCLUSION: The results indicate that estrogens might enhance endothelium-dependent and endothelium-independent vasodilatation in the microcirculation of women.