214.High cardiac level
每天朗读一段医学影像学英语文章
At this level, you should be able to identify the left atrium, right atrium, aortic root, and right ventricular outflow tract. The left atrium (LA) occupies the posterior and central portion of the heart. One or more pulmonary veins may be seen to enter the left atrium (solid white arrow). The right atrium (RA) produces the right heart border and lies anteriorly and to the right of the left atrium. The right ventricular outflow tract (RVOT) lies anterior, lateral and superior to the root of the aorta (Ao). (DA = descending thoracic aorta; LV = left ventricle.)
在这个层面，可以看到左心房、右心室、主动脉根部和右心室流出道。左心房（LA）位于心脏的后部和中央部分。可以看到一个或多个肺静脉进入左心房。右心房（RA）是心脏的右侧边界的组成部分，位于左心房前右侧。右心室流出道（RVOT）位于主动脉根部（AO）的前、外侧和上方。
Extensive Reading
Cardiac CT
Faster multislice CT scanners and ECG-gated acquisition to reduce degradation of the image by cardiac motion, along with powerful computer algorithms, now allow for the imaging and three-dimensional reconstruction of the coronary arteries and quantitative measurement of the amount of coronary artery calcium. The administration of intravenous contrast allows evaluation of vessel patency with identification of thrombus in the lumen or plaque in the vessel wall.
By reconstructing multiple phases of the cardiac cycle, it is also possible to analyze wall motion and evaluate ejection fraction and myocardial perfusion.
Calcium scoring is based on the premise that the amount of calcium in the coronary arteries is related to the degree of atherosclerosis and that quantifying the amount of calcium may help predict future cardiac events related to coronary artery disease.
· The scoring is done by calculations that include the amount of calcium visualized in the coronary arteries (Fig. 11-10).
· The absence of coronary artery calcification has a high negative predictive value for significant luminal narrowing.
It is possible to perform an ultrafast CT scan in the emergency department that will allow for the simultaneous evaluation of coronary artery disease, aortic dissection, and pulmonary thromboembolic disease—the so-called triple scan for patients who present with acute chest pain.
来源：每天朗读一段医学影像学英语文章
圈主
深圳市人民医院放射科副主任医师杨敏洁