冠状动脉粥样硬化性心脏病英文课件.pptVIP

* 此图表明了斑块形成过程。早期阶段以损伤处出现少量泡沫细胞为主。以后脂质沉积产生脂质条纹。然后，脂质沉积在血管壁的细胞外间隙。在30岁后，可形成粥样斑块或肉眼看不见的脂质核心。应注意到，在此时斑块的主要生长方式为脂质沉积。40岁后，由于在粥样斑块核心上，含有平滑肌细胞和胶原的基质增多，故可见更多的纤维斑块。最后，如果斑块不稳定，可能被侵蚀或破裂。一旦斑块内溶物接触血液，可能导致血小板激活及血栓形成。 Stary, et al. Circulation 1995; 92: 1355-1374 * Atherosclerotic plaques have 2 main components—a soft lipid-rich core and a hard collagen-rich fibrous cap.1 In stable plaques, a thick fibrous cap may represent 70% of plaque volume. It stabilizes the plaque and prevents it from undergoing rupture.1 In contrast, unstable plaques have a thin fibrous cap and are at greater risk for rupture. In unstable plaques, the lipid-rich core may represent the majority of the plaque volume.1 Falk reviewed the work of other investigators regarding severity of stenosis and its association with the risk of MI. Results showed that 86% of MIs resulted from lesions that were 70% stenosed.1 Most experts prior to Falk thought that patients had heart attacks because of blockages that increased in size until they eventually blocked the blood vessel and caused a heart attack. Based on the findings by Falk, we now know the primary cause of heart attacks is the rupture of unstable plaques that are 70% stenosed and are clinically silent. Approximately 200 patients from 4 studies were used to generate these results, which have been confirmed in other studies. References 1 Falk E, Shah PK, Fuster V. Coronary plaque disruption. Circulation. 1995;92:657-671. 2 Libby P. Molecular bases of the acute coronary syndromes. Circulation. 1995;91:2844-2850. * Topic II - 54 * * * The catheter is passed through the sheath, over the guidewire, retrograde (against blood flow) to the aorta and the aortic valve and origins of the left and right coronary system. Dye is injected into the vessel for visualization of the left and right coronary arteries and left ventricle. * * Cardiovascular cause Myocardial infarction Pericarditis Aortic dissection Pulmonary embolism Pulmonary hypertension * * Noncardi