冠心病+成人教育.pptVIP

* * * * * * * * Slide 4 Pathophysiology of ACS Various factors affect the risk that an atherosclerotic plaque will rupture, including the tensile strength of the fibrous cap and the shear stresses to which it is subjected. Unstable plaques at high risk of rupture typically have a large lipid core, a thin cap and contain large numbers of macrophages but relatively few smoothmuscle cells. Rupture or fissure of the plaque exposes the thrombogenic core of the lesion and leads to adhesion and aggregation of platelets and thrombus formation. A large fissure typically results in the formation of a large thrombus that completely occludes the coronary artery, causing acute MI, characterized by persistent ST-segment elevation and subsequent development of new Q-waves on the electrocardiogram (ECG). A smaller fissure may result in a mural thrombus that partially or transiently occludes the artery, causing acute myocardial ischemia without persistent ST-segment elevation. The clinical diagnosis is unstable angina, or if thereis biochemical evidence of myocardial damage, non-Q-wave MI. ACS is a classic example of atherothrombosis (plaque rupture and thrombus formation). References Fuster V, Badimon L, Badimon JJ et al. N Engl J Med 1992;326:310–318. Davies MJ. Circulation 1990;82(Suppl 3):II38–46. * * * * * * * * * * * * * * * * * * * * * * * * * 鉴别诊断： 心血管神经官能症 急性心肌梗死 其它疾病引起的心绞痛 肋间神经痛 不典型疼痛 诊断与鉴别诊断 * 住院卧床休息，防止心肌梗死 硝酸酯类 Β受体阻滞剂 他汀类药物 如变异型心绞痛用钙拮抗剂 阿斯匹林、氯比格雷、肝素 PTCA、CABG 治 疗 * 心肌梗死 * 由于冠状动脉血供急剧减少或中断，使相应的心肌严重而持久地急性缺血而坏死。 急性心肌梗死 * 先兆：初发性心绞痛或原有心绞痛加重 症状： 疼痛 全身症状 胃肠道症状 心律失常 低血压和休克 心力衰竭：急性左心衰 临床表现 * 体征： 心率增快、心脏扩大 心尖区S1低钝，出现S3、S4 10-20%病人在起病2-3天出现心包摩擦音； 二尖瓣乳头肌功能失调→心尖部粗糙收缩期杂音 血压 可有心律失常 休克 心衰相关体征 临床表现 * 心电图 特征性改变 ST段增高呈弓背向上型 宽而深的病理性Q波：面向心肌坏死区导联 T波倒置 心电图及实验室检查 * 动态性改变 超急性期： 起病后数小时内，无异常/高尖T波 急性期： 数小时后，ST-T成单向曲线；R波降低，出现病理性Q波 亚急性期： 数日至2周，ST回到基线，T平坦或倒置。 陈旧期： 数周至数月后，T波对称倒置。 心电图及实验室检查 * 心肌梗死的心电图演变 * 三、定位、定范围 导联 前间隔 局限前壁 前侧壁 广泛前臂 下壁 下间壁 下侧壁 高侧壁 正后壁 V1 ＋ ＋ ＋ V2 ＋ ＋ ＋ V3 ＋ ＋ ＋