用户名: 密码: 验证码:
In?vivo assessment of endothelial function in human lower extremity arteries
详细信息    查看全文
文摘
| Figures/TablesFigures/Tables | ReferencesReferences

Objective

Endothelial function has been measured in preclinical studies in human brachial and coronary arteries but not in lower extremity arteries affected by atherosclerosis. We describe a novel, first-in-man evaluation of endothelial function of the superficial femoral arteries (SFAs) in patients with peripheral arterial disease (PAD).

Methods

Enrolled were 25 patients with PAD requiring lower extremity angiography. Endothelial-dependent relaxation was measured using intravascular ultrasound (IVUS) imaging and a Doppler flow wire after the infusion of acetylcholine (Ach). IVUS-derived virtual histology of the same vessel was calculated. Endothelial-independent relaxation was measured with an infusion of nitroglycerin (200?¦Ìg). Levels of nitric oxide and serum nitric oxide metabolites were determined by laboratory analysis.

Results

Patients (48 % male; mean age, 62?years) had a history of hypertension (80 % ), coronary disease (36 % ), and diabetes (40 % ). The mean SFA diameter was 5.2?¡À 1?mm (range, 3.2-6.9?mm). Patients tolerated Ach infusion with no adverse events. Endothelial-dependent relaxation increased over baseline for all patients with Ach infusion of 10?6 to 10?4. At Ach 10?4, diameter (0.5 % ) and area (1.8 % ) changes in the diseased SFAs were modest and insignificant; however, average peak velocity of blood flow significantly increased 26 % , 46 % , and 63 % with an Ach 10?6 to 10?4 infusion. Calculations of limb volumetric flow (68 % at Ach 10?4) were significantly increased after Ach infusion. Lower extremity nitric oxide levels were slightly lower than systemic venous levels (P?= .04). Nitroglycerin infusion indicated normal smooth muscle responsiveness (3 % diameter, 9 % area, and 116 % velocity change over baseline). IVUS-virtual histology plaque stratification indicated predominantly fibrous morphology (46 % ; necrotic core, 29 % ; calcium, 18 % ). Atheroma burden was 14.9?¡À 5.5?mm3/cm and did not correlate with endothelial responsiveness.

Conclusions

Endothelial function can be measured directly in human lower extremity arteries at the sites of vascular disease. Despite extensive atherosclerosis, endothelial function is still intact. These data support the application of regional endothelial-specific biologic therapies in patients with PAD.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700