用于评估微血管功能及其与心血管风险状况关系的二维空间选择性实时磁共振成像

2D-spatially-selective real-time magnetic resonance imaging for the assessment of microvascular function and its relation to the cardiovascular risk profile.

作者信息

Schwitter Juerg, Oelhafen Markus, Wyss Barbara M, Kozerke Sebastian, Amann-Vesti Beatrice, Lüscher Thomas F, Boesiger Peter

机构信息

Division of Cardiology and CardioVascular Center, University Hospital Zurich, Zurich, Switzerland.

出版信息

J Cardiovasc Magn Reson. 2006;8(5):759-69. doi: 10.1080/10976640600737573.

DOI:10.1080/10976640600737573

PMID:16891237

Abstract

BACKGROUND

While local endothelial dysfunction of conduit arteries is well recognized as an early step in atherogenesis, contradictory observations are reported with regard to alterations in the microcirculation and their association with cardiovascular risk factors (RFs). A real-time MR approach was developed to investigate the relationship between the RFs profile and microcirculatory alterations assessed as impairment of reactive hyperemic flow in the leg circulation.

METHODS

The MR technique was applied to patients (n = 17, Pats1) with 1.8 +/- 0.8 RFs but without peripheral arterial occlusive disease (PAD), to age-matched healthy controls (n = 13, Con1), to young controls (n = 12, 23 +/- 4 y), and to patients with RFs and PAD (n = 8, Pats2).

RESULTS

Superficial femoral artery (SFA) peak hyperemic flow in Pats1 was reduced vs Con1 (24.6 +/- 4.2 vs 30.4 +/- 7.3 mL min-1 100 mL-1 calf tissue, p < 0.02), and minimal vascular resistance increased incrementally with the number of RFs and with Framingham and Procam risk scores. Flow-mediated vasodilation (FMD) of the SFA was blunted in both Pats1 and Con1 (-0.5 +/- 3.4% and +0.6 +/- 3.2%, respectively, both ns vs 0). In young controls, peak hyperemic flow (30.1 +/- 3.3 mL min-1. 100 mL-1) and endothelium-independent vasodilation (9.2 +/- 10.0%) were preserved, while FMD was minimal (2.0 +/- 5.9%,p < 0.02 vs endothelium-independent vasodilation). In Pats2, peak hyperemic flow was severely reduced (12.2 +/- 3.6 mL min-1 100 mL-1, p < 0.0003 vs Con1 and Pats1), and both FMD and endothelium-independent vasodilation were absent.

CONCLUSIONS

Reactive hyperemic flow in the SFA, reflecting microcirculatory function of the lower limb, gradually decreases with increasing cardiovascular risk suggesting a role for microvascular dysfunction in atherogenesis. The presented MR approach might become a valuable tool to study (micro)-vascular pathophysiology.

摘要

背景

虽然人们普遍认为输送动脉的局部内皮功能障碍是动脉粥样硬化形成的早期步骤，但关于微循环改变及其与心血管危险因素（RFs）的关联，却有相互矛盾的观察结果报道。本研究开发了一种实时磁共振成像方法，以探究RFs谱与以腿部循环中反应性充血血流受损来评估的微循环改变之间的关系。

方法

将磁共振成像技术应用于具有1.8±0.8个RFs但无外周动脉闭塞性疾病（PAD）的患者（n = 17，患者1组）、年龄匹配的健康对照者（n = 13，对照1组）、年轻对照者（n = 12，23±4岁）以及患有RFs和PAD的患者（n = 8，患者2组）。

结果

与对照1组相比，患者1组股浅动脉（SFA）的充血峰值血流降低（分别为24.6±4.2与30.4±7.3 mL·min⁻¹·100 mL⁻¹小腿组织，p < 0.02），并且最小血管阻力随着RFs数量、弗雷明汉风险评分和Procám风险评分的增加而逐渐增加。患者1组和对照1组的SFA血流介导的血管舒张（FMD）均减弱（分别为-0.5±3.4%和+0.6±3.2%，两者与0相比均无统计学意义）。在年轻对照者中，充血峰值血流（30.1±3.3 mL·min⁻¹·100 mL⁻¹）和非内皮依赖性血管舒张（9.2±10.0%）得以保留，而FMD最小（2.0±5.9%，与非内皮依赖性血管舒张相比，p < 0.02）。在患者2组中，充血峰值血流严重降低（12.2±3.6 mL·min⁻¹·100 mL⁻¹，与对照1组和患者1组相比，p < 0.0003），且FMD和非内皮依赖性血管舒张均消失。