CT冠状动脉造影不同对比剂用量对冠状动脉及冠状静脉窦的价值体会

目的〖KG*2〗分析CT冠状动脉造影时对比剂用量对于不同心功能冠心病患者的冠状动脉、冠状静脉窦强化程度的影响水平，探讨CT冠状动脉造影对冠心病的诊断价值及增强扫描时血管对比剂的应用体会。 〖HTH〗方法〖KG*2〗入选256层螺旋CT冠动脉血管成像的疑似冠心病患者98例。首先根据患者超声心动图结果分为A组（射血分数≥50%，n=58）、B组（射血分数＜50%，n=40），每组又采用随机数表法分为A1组、A2组各29例，B1组、B2组各20例。增强扫描时，A1组、B1组对比剂用量（按体重）为0.7 mL/kg；A2组、B2组对比剂用量（按体重）为0.8 mL/kg。测定注入对比剂后患者升主动脉、左前降支近段、右冠状动脉远段、左冠状动脉主干和冠状静脉窦CT最大值，对造影图像质量进行评分，将各组上述指标数值进行比较。 〖HTH〗结果〖KG*2〗4组前降支近段和右冠状动脉远段CT最大值总体差异有统计学意义（P＜0.001），经两两比较发现，A1组与A2组间差异无统计学意义，其他组间比较差异均有统计学意义；4组冠状静脉窦CT最大值总体差异有统计学意义（P＜0.001），经两两比较发现，各组间均差异有统计学意义；4组图像质量评分总体差异有统计学意义（P＜0.001），经两两比较发现，A1组与A2组间差异无统计学意义，其他组间比较差异均有统计学意义（P＜0.05）。 〖HTH〗结论〖KG*2〗对于心功能正常的患者，使用低剂量对比剂（0.7 mL/kg）并不减弱冠状动脉成像质量；对于心功能降低的患者，低剂量对比剂会降低冠状动脉成像质量。减少对比剂用量会降低冠状静脉窦的CT最大值；在应用相同剂量对比剂的情况下，心功能正常组的冠状静脉窦CT最大值低于心功能不全组。

The value of different contrast dosage in CT coronary angiography for coronary artery and coronary venous sinus

ObjectiveTo analyze the influence of contrast medium dosage on the enhancement of coronary artery and coronary venous sinus in patients with coronary heart disease of different severity during CT coronary angiography, and to explore the diagnostic value of CT coronary angiography for coronary heart disease and the application of contrast medium in enhanced scanning. MethodsNinety-eight patients detected by Philips 256-slice spiral CT coronary angiography were divided into group A(ejection fraction≥50%, n=58) and group B(ejection fraction<50%, n=40) according to the echocardiography reports. Each group was further divided into four groups by random number table method, 29 cases in group A1, 29 cases in group A2, 20 cases in group B1 and 20 cases in group B2. At the time of scanning, the dosage of contrast agent in group A1 and B1(according to body weight) was 0.7 mL/kg; the dosage of contrast agent in group A2 and B2(according to body weight) was 0.8 mL/kg; the maximum CT values of ascending aorta, proximal left anterior descending branch, distal right coronary artery, main left coronary artery and coronary sinus were measured after injection of contrast agent in four groups, and the dosage and injection rate of contrast agent in four groups were also counted. Scanning time, delay time and image quality of four groups were scored, and the values of the above indexes in each group were compared. ResultsThe overall difference of the 4 groups with the maximum CT value of the proximal anterior descending branch and the distal right coronary artery was statistically significant(P＜0.001). Pairwise comparison showed that there was no significant difference between the A1 group and the A2 group, while there were statistically significant differences in other groups. The overall difference of the 4 groups with the maximum CT value of coronary venous sinus was statistically significant(P＜0.001). Pairwise comparison showed that there were statistically significant differences among all groups. The overall difference of image quality scores in 4 groups was statistically significant(P＜0.001). Pairwise comparison showed that there was no significant difference between A1 group and A2 group, while there were statistically significant differences in the other groups. ConclusionIn patients with normal cardiac function, the use of low-dose contrast agents(0.7 mL/kg) did not impair the quality of coronary artery imaging. For patients with reduced cardiac function, low-dose contrast agents can reduce the quality of coronary artery imaging. Reducing the amount of contrast agent will reduce the CT maximum value of coronary venous sinus（P＜0.05）. With the same dose of contrast agent, the maximum CT value of coronary venous sinus in normal cardiac function group was lower than that in cardiac insufficiency group.