Bleie Øyvind, Strand Elin, Ueland Per M, Vollset Stein E, Refsum Helga, Igland Jannicke, Nordrehaug Jan E, Nygård Ottar K
Department of Heart Disease, Haukeland University Hospital, Bergen, Norway.
Coron Artery Dis. 2011 Jun;22(4):270-8. doi: 10.1097/MCA.0b013e328344fff4.
Plasma concentration of total homocysteine is associated with risk of cardiovascular disease in epidemiological studies. We wanted to examine the effects of B-vitamin therapy, which may lower total homocysteine, on coronary flow and vascular function in patients with established coronary artery disease (CAD).
Forty patients with stable CAD, mean (standard deviation) aged 57.8 (9.0) years, recruited into the Western Norway B-Vitamin Intervention Trial, were randomly assigned to daily oral treatment with 0.8 mg of folic acid and 0.4 mg of vitamin B12 or placebo, and 40 mg of vitamin B6 or placebo, using a 2 × 2 factorial design. At baseline, and after 9 and 24 months, coronary blood flow was assessed by coronary angiography and Doppler flow-wire measurements during intracoronary infusion of saline (basal), incremental doses of acetylcholine, adenosine, and nitroglycerin.
We found a significant increase in basal (P < 0.02) and adenosine-induced (P < 0.05) coronary blood flow in patients who received folic acid/vitamin B12 for 24 months, compared with placebo or vitamin B6 alone. Folic acid/vitamin B12 or vitamin B6 treatment did not change endothelial-dependent response after acetylcholine infusion or flow-dependent proximal dilatation in response to adenosine-induced maximal hyperemia (P ≥ 0.45).
Long-term treatment with a combination of folic acid and vitamin B12 increase basal and adenosine-induced maximal coronary blood flow. This may reflect improved microvascular function in patients with stable CAD.
在流行病学研究中，血浆总同型半胱氨酸浓度与心血管疾病风险相关。我们想要研究可能降低总同型半胱氨酸的B族维生素疗法对已确诊冠心病（CAD）患者冠状动脉血流和血管功能的影响。
40例稳定型CAD患者，平均（标准差）年龄57.8（9.0）岁，入选挪威西部B族维生素干预试验，采用2×2析因设计，随机分配至每日口服0.8 mg叶酸和0.4 mg维生素B12或安慰剂，以及40 mg维生素B6或安慰剂组。在基线时以及9个月和24个月后，通过冠状动脉造影和冠状动脉内输注生理盐水（基础状态）、递增剂量的乙酰胆碱、腺苷和硝酸甘油期间的多普勒血流导丝测量来评估冠状动脉血流。
我们发现，接受叶酸/维生素B12治疗24个月的患者，与单独使用安慰剂或维生素B6相比，基础（P<0.02）和腺苷诱导的（P<0.05）冠状动脉血流显著增加。叶酸/维生素B12或维生素B6治疗在输注乙酰胆碱后并未改变内皮依赖性反应，或在腺苷诱导的最大充血反应中未改变血流依赖性近端扩张（P≥0.45）。
叶酸和维生素B12联合长期治疗可增加基础和腺苷诱导的最大冠状动脉血流。这可能反映了稳定型CAD患者微血管功能的改善。
