冷加压实验超声心动图及冠脉血流显像技术评价冠脉微循环内皮功能

目的应用冷加压实验超声心动图及冠脉血流显像技术评价冠状动脉造影结果正常的冠心病高危人群的微循环内皮功能。方法冠脉造影结果正常受检者40例，分为无冠心病危险因素的对照组20例和冠心病高危人群组20例。分别于静息状态下、冷加压实验后、舌下含服硝酸甘油后测量冠状动脉左主干内径并计算其内径变化率；测量冠状动脉左前降支舒张期峰值血流速度，并计算其流速变化率，比较两组干预状态下的内径变化率和流速变化率。结果静息状态下两组冠脉内径及峰值流速基础值之间均无统计学差异（P〉0．05）。冷加压实验后，冠心病高危人群组冠脉内径扩张率（4．53±2．65）％、流速增加率（23．64±5．72）％，低于对照组的（11．37±3．29）％及（43．76±4．28）％（P〈0．05）。含服硝酸甘油后，两组内径变化率和流速变化率之间无统计学差异（P〉0．05）。结论冠心病高危人群在冠脉造影结果正常时可能已合并冠状动脉微循环内皮功能损伤，冷加压实验超声心动图评价冠状动脉微循环内皮功能有一定可行性。

Evaluation of coronary microcirculation endothelial function by cold pressor test echocardiography and coronary flow imaging

Objective To evaluate coronary microcirculation endothelial function in patients who had high risk factors for coronary artery disease but negative results in coronary arteriongraphy by cold pressor test （CPT） echocardiography and coronary flow imaging. Methods Fourty subjects with negative results by coronary arteriongraphy were divided into two groups. Group Ⅰ was20 subjects without risk factors for coronary artery disease, and group Ⅱ was 20 subjects with high risk factors for coronary artery disease. The left main coronary（LMC） diameter and the coronary peak velocity （CPV） were measured on rest condition, CPT and after taking sublingual nitroglycerin in both groups respectively. The percentage changes of LMC diameter, CPV after CPT and nitroglycerin administration in two groups were calculated to assess the endothelium function. Results There was no significant difference in coronary diameter and basic value of peak value flow in two groups on rest condition （ P 〉 0.05）. After CPT, the percentage increase of LMC diameter and the CPV in group I was （4.53±2.65） % and （23.64±5.72）%, which were lower than those in group Ⅱ, （11.37±3.29） % and（43.76±4.28） （P 〈 0.05）. After nitroglycerin administration, there was no significant difference between two groups （ P 〉 0.05）. Conclusion Coronary microcirculation endothelial dysfunction could be detected in groups with risk factors for coronary artery disease by cold pressor echocardiography, which is considered as an useful non- interventional method for clinical analysis, disease risk assessment and treatment.