Department of Medicine, Renal Division, the Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, USA.
Circ Cardiovasc Imaging. 2010 Nov;3(6):663-71. doi: 10.1161/CIRCIMAGING.110.957761. Epub 2010 Sep 17.
coronary microvascular dysfunction may underlie the high cardiovascular risk associated with chronic kidney disease (CKD), but the effects of CKD on coronary microvasculature function remain uncertain.
we assessed myocardial blood flow changes in mild-to-moderate CKD and analyzed the association between creatinine clearance (CrCl) and peak myocardial blood flow and coronary flow reserve (CFR) measured as the ratio of stress to rest perfusion at baseline and at 1 year in 435 nondiabetic individuals who underwent quantitative rest and pharmacological stress positron emission tomography imaging. At baseline, CFR was significantly associated with CrCl (β per 10 mL/min increase, 0.07; P=0.001). Factors such as age and blood pressure accounted for this association, and it was not significant in adjusted analyses (β=-0.02, P=0.53). Peak flow was not associated with CrCl in either crude or adjusted analyses (β per 10 mL/min=-0.02 mL/min per g, P=0.29). Although change in peak flow at 1 year was similar in patients with and without CKD, CrCl was a strong and independent predictor of a higher rate of change in CFR, with a loss of 0.11 CFR units/y (95% confidence interval, 0.01 to 0.20) for each 10 mL/min drop in CrCl (P=0.03).
these findings demonstrate that mild-to-moderate CKD is not independently associated with a reduction in peak myocardial flow or CFR and suggests that microvascular changes are unlikely to explain the high cardiovascular mortality in mild to moderate CKD. Loss of CFR, however, may accelerate in mild to moderate CKD. Further studies are needed to determine whether these changes lead to more significant reductions that may reduce peak flows and CFR and contribute to cardiovascular risk in more severe CKD.
冠状动脉微血管功能障碍可能是慢性肾脏病（CKD）相关心血管风险高的原因，但 CKD 对冠状动脉微血管功能的影响仍不确定。
我们评估了轻度至中度 CKD 患者的心肌血流变化，并分析了 435 名非糖尿病个体的静息和药物负荷正电子发射断层扫描成像的定量静息和药物负荷灌注数据。在基线和 1 年时，通过测量应激和休息时的灌注比来分析肌酐清除率（CrCl）与峰值心肌血流和冠状动脉血流储备（CFR）之间的关系。在基线时，CFR 与 CrCl 显著相关（每增加 10 mL/min，β为 0.07；P=0.001）。年龄和血压等因素解释了这种相关性，在调整分析中没有统计学意义（β=-0.02，P=0.53）。在未调整和调整分析中，峰值血流均与 CrCl 无关（每增加 10 mL/min，β=-0.02 mL/min/g，P=0.29）。尽管在有和无 CKD 的患者中，1 年内峰值血流的变化相似，但 CrCl 是 CFR 变化率的一个强有力且独立的预测因素，CrCl 每下降 10 mL/min，CFR 损失 0.11 CFR 单位/y（95%置信区间，0.01 至 0.20）（P=0.03）。
这些发现表明，轻度至中度 CKD 与峰值心肌血流或 CFR 降低无关，提示微血管变化不太可能解释轻度至中度 CKD 患者的高心血管死亡率。然而，CFR 的损失可能会在轻度至中度 CKD 中加速。需要进一步研究来确定这些变化是否会导致更显著的减少，从而降低峰值流量和 CFR，并在更严重的 CKD 中导致心血管风险。
