急性冠状动脉综合征的血管内超声特征

Intravascular ultrasound characteristics of acute coronary syndrome

目的 应用血管内超声研究急性冠状动脉综合征的病变基础。方法 113例患者 [男78例 ,女 35例 ,平均年龄 (6 3± 12 )岁 ]接受冠状动脉造影及血管内超声检查。其中不稳定性心绞痛 5 7例 ,急性心肌梗死 (1个月内 ) 34例 ,稳定性心绞痛 2 2例。血管内超声检查 :根据斑块回声的强弱 ,将其分为以下几类 :(1)软斑块 ,粥样硬化斑块的回声比血管壁外膜的回声弱 ;(2 )纤维斑块 ,粥样硬化斑块的回声等于或超过血管壁外膜 ;(3)钙化斑块 ,表现为比血管管壁外膜回声强并且后方有清楚的声影。软性斑块成分或硬性斑块成分超过 80 %判定为软斑块或硬斑块 ,否则判定为混合性斑块。结果 与稳定性心绞痛相比 ,血管内超声发现 4 8例 (84 % )不稳定性心绞痛及 30例 (88% )急性心肌梗死患者的目标病变为软斑块 (P <0 0 1)。 6例 (11% )不稳定性心绞痛及 6例 (18% )急性心肌梗死患者目标病变含有脂质池。并发现 9例 (16 % )不稳定性心绞痛及 12例 (35 % )急性心肌梗死患者伴有斑块破裂 (P <0 0 1)。稳定性心绞痛的病变则以硬斑块、钙化病变为多。另外 ,在不稳定性心绞痛组及急性心肌梗死组中半数以上的目标病变呈偏心性。结论 血管内超声可以识别不稳定斑块 (富含脂质池及薄纤维帽 ) 。

Objective To study the pathologic basis of acute coronary syndrome using intravascular ultrasound(IVUS) Methods One hunderd and thirteen patients [male 78, mean age (63±12) years] underwent coronary artery angiography(CAG) and IVUS examinations Unstable angina was diagnosed in 57 patients, acute myocardial infarction (within one month)in 34 and stable angina in 22 IVUS examinations : plaque was classified into 3 types according to different ultrasound patterns of tissue reflection:(1) Soft plaque appeared on ultrasound as an echo reflection weaker than the adventitia echogenicity;(2) Fibrous plaque appeared on ultrasound as an intense echo reflection greater than the adventitia echogenicity;(3) Calcification plaque appeared on ultrasound as an intense characteristic echo reflection with dropout of echoes peripherally, which was termed shadowing More than 80% plaque occupied by soft (or hard) echo reflection was defined as soft(or hard)plaque Otherwise, the plaque was defined as mixed plaque Results Compared with patients with stable angina, 48(84%) patients with unstable angina and 30(88%) patients with acute myocardial infarction had soft plaque( P <0 01) and 6(11%) patients with unstable angina and 6(18%)patients with acute myocardial infarction had plaques with lipid pool In addition, plaque rupture was found in 9 (16%)patients with unstable angina and 12(35%)patients with acute myocardial infarction ( P <0 01) Patients with stable angina had more hard plques and more calcification Besides, it was shown that more than half of the lesions in acute coronary syndrome were eccentric Conclusion The IVUS can accurately identify unstable plaque(with lipid rich pool and thin fibrotic cap) The rupture of unstable plaque is confirmed to be related to the occurrence of acute coronary syndrome