心脏计算机断层血管造影(CCTA)

什么是心脏CT扫描?

A cardiac CT angiography (CCTA) scan is a noninvasive test that uses x射线 给你的心脏和血管拍照. A computer combines the images to create a three-dimensional (3D) image of your heart.

A CCTA scan is used to help find the presence of and percent of narrowing (stenosis) in the coronary arteries and blood vessels that supply blood to the heart or other parts of the body.

Multidetector CT, or MDCT, scans work fast and are very detailed. They can produce better images with lower radiation exposure.

为什么人们要做CCTA扫描?

您可能需要进行CCTA扫描，当其他测试，如 胸部x光片, 心电图(ECG), 超声心动图(回声), or 压力测试, don’t give your health care team enough information about your heart.

The test can help your health care team gather additional information on:

• Your heart’s structure and how well your heart pumps blood.
• 心脏肌肉上的疤痕 心脏病. 
• Fluid in the pericardial sac that covers the surface of the heart.
• The amount of plaque buildup and narrowing of your coronary arteries.
• Any abnormalities in the large blood vessels leaving the heart.
• 心脏病发作的风险.

它能帮助显示你是否有心脏病吗?

When contrast dye (iodine) is given during the CCTA scan, 它可以显示你的心脏动脉阻塞. This is useful to see if chest discomfort comes from lack of blood flow to the heart muscle due to blocked heart arteries (心绞痛). 如果心脏动脉正常, your health care team can confidently look into other causes of chest pain that aren’t related to the heart.

使用对比染料，CCTA扫描也可以检查是否 冠状动脉旁路移植术 心脏搭桥手术后保持开放或检测 先天性心脏缺陷 (problems present at birth) and how your ventricles are working. 

我可以做CCTA扫描而不是冠状动脉造影吗?

CCTA扫描不能代替 冠状动脉造影(PDF) or 心导管检查. Coronary angiography is the gold standard method for showing blockages in the coronary arteries. It also gives specific information about how your heart is working. In some cases, a CCTA may be done instead of a coronary angiogram. This is based on patient factors as well as the imaging capabilities of the hospital or outpatient center.

有哪些风险??

CCTA扫描会让你暴露在辐射中. Further studies on safety and possible risks are warranted. Talk with your health care team about safety and risks for any test you’re undergoing.

如果你怀孕了，告诉你的医疗团队. If the test is not urgent, ask them about delaying it until after your pregnancy. Also, if you have kidney problems, you may not be able to receive contrast dye. Your health care team will measure your kidney function before the test and may give you medications to help protect your kidneys from potential damage.

Some people have allergic reactions to the contrast dye that’s sometimes used in the test. Before the test, tell your health care professional if you’re allergic to dyes, iodine or shellfish.  Depending on the type of reaction you have previously had, certain medications like antihistamines and steroids may be given before the test to greatly reduce the chance of an allergic reaction. 在严重过敏反应的情况下, contrast dye will not be used and instead a test that doesn’t require contrast may be used.

我该如何准备CCTA扫描?

Talk to your health care professional about how long to fast before the test.

考试过程中会发生什么?

Technicians perform the CCTA scan in hospitals or special outpatient clinics.

• Electrodes will be attached to your chest to monitor your ECG. The ECG also helps the computer connected to the CT scanner create clear pictures of your heart.
• When you're ready, the table slowly moves inside the machine. 扫描仪环绕着你，但不触及你.
• If a contrast dye is used, it's injected through an intravenous line placed in an arm vein.
• You may also be given medicines that widen your heart arteries or slow down your heartbeat. These medicines make it easier to see any blockages in the heart arteries.
• The technician will watch you closely through a window. 你可以通过双向对讲机与他或她交谈.
• The technician will ask you to hold your breath for short periods.
• CT扫描大约需要5-10分钟.

CCTA扫描后会发生什么?

• Your health care professional will let you know when to resume normal activities.
• After the health care team gets a written report of the test results, they will make an appointment to discuss the results and next steps with you.