心脏核磁共振

定义

心 磁共振成像 is an imaging method that uses powerful magnets and radio waves to create pictures of the heart. 它不使用辐射(x射线).

Single 磁共振成像 (MRI) images are called slices. The images can be stored on a computer or printed on film. One exam produces dozens or sometimes hundreds of images.

该测试可作为a的一部分 胸部核磁共振.

选择的名字

Magnetic resonance imaging - cardiac; Magnetic resonance imaging - heart; Nuclear magnetic resonance - cardiac; NMR - cardiac; MRI of the heart; Cardiomyopathy - MRI; 心 failure - MRI; Congenital heart disease - MRI

如何执行测试

You may be asked to wear a hospital gown or clothing without metal fasteners (such as sweatpants and a t-shirt). Some types of metal can cause blurry images or be attracted to the powerful magnet.

You will lie on a narrow table, which slides into a large tunnel-like tube.

有些检查需要特殊的染料(造影剂)。. The dye is most often given before the test through a vein (IV) in your hand or forearm. The dye helps the radiologist see certain areas more clearly. 这与CT扫描所用的染料不同.

During the MRI, the person who operates the machine will watch you from another room. The test most often lasts 30 to 60 minutes but may take longer.

如何准备考试

You may be asked not to eat or drink anything for 4 to 6 hours before the scan.

Tell your health care provider if you are afraid of close spaces (have claustrophobia). You may be given a medicine to help you feel sleepy and less anxious, 或者你的十大赌博平台排行榜可能会建议你做“开放式”核磁共振, 在这种情况下，机器离身体不那么近.

在测试前，告诉你的十大赌博平台排行榜你是否有:

• 脑动脉瘤夹
• 某些类型的人工心脏瓣膜
• 心脏除颤器或起搏器
• 内耳(耳蜗)植入物
• Kidney disease or dialysis (you may not be able to receive contrast)
• 最近放置的人工关节
• 某些类型的血管 支架
• Worked with sheet metal in the past (you may need tests to check for metal pieces in your eyes)

因为核磁共振成像含有强磁铁, metal objects are not allowed into the room with the MRI scanner:

• Pens, pocketknives, and eyeglasses may fly across the room.
• Items such as jewelry, watches, credit cards, and hearing aids can be damaged.
• Pins, hairpins, metal zippers, and similar metallic items can distort the images.
• Removable dental work should be taken out just before the scan.

考试的感觉如何

心脏核磁共振检查不会引起疼痛. Some people may become anxious when inside the scanner. If you have a hard time lying still or are very anxious, you may be given medicine to relax. Too much movement can blur MRI images and cause errors.

The table may be hard or cold, but you can ask for a blanket or pillow. The machine produces loud thumping and humming noises when turned on. 十大赌博平台排行榜可能会给你戴上耳塞，以减少噪音.

An intercom in the scanner allows you to speak to the person operating the exam at any time. Some MRI scanners have televisions and special headphones to help pass the time.

There is no recovery time, unless sedation was necessary. (You will need someone to drive you home if sedation was given.)核磁共振扫描后, 你可以恢复正常饮食了, 活动, 和药品, 除非你的十大赌博平台排行榜另有说明.

为什么要进行测试

MRI provides detailed pictures of the heart and blood vessels from many views. 经常, it is used when more information is needed after you have had an echocardiogram or heart CT scan. MRI is more accurate than CT scan or other tests for certain conditions, 但对其他人来说就不那么准确了.

心脏MRI可用于评估或诊断:

• 心脏病发作后的心肌损伤
• 先天性心脏缺陷
• 心脏肿瘤和生长
• 心肌衰弱或其他问题
• 心力衰竭的症状

异常结果意味着什么

Abnormal results may be due to many things, including:

• 心脏瓣膜紊乱
• 心脏周围囊状覆盖物中的液体(心包积液)
• 血管或心脏周围的肿瘤
• 心房粘液瘤 或者心脏又长了一个肿瘤
• Congenital heart disease (heart problem that you are born with)
• 损伤或死亡的心脏肌肉，看到后 心脏病
• 心肌炎症心肌的炎症
• 异常物质对心肌的浸润
• Weakening of the heart muscle, which can be caused by sarcoidosis or amyloidosis

风险

核磁共振成像不涉及辐射. The magnetic fields and radio waves used during the scan have not been shown to cause any significant side effects.

Allergic reactions to the dye used during the exam are rare. The most common type of contrast (dye) used is gadolinium. 它很安全. The person operating the machine will monitor your heart rate and breathing as needed. Rare complications can occur in people with severe kidney problems.

People have been harmed in MRI machines when they did not remove metal objects from their clothes or when metal objects were left in the room by others.

MRI is most often not recommended for traumatic injuries. 牵引 and life-support equipment cannot safely enter the scanner area.

MRIs can be costly, take a long time to perform, and are sensitive to movement.

参考文献。

克莱默CM，贝勒GA，哈格斯皮尔KD. 无创心脏显像. 参见:Goldman L, Schafer AI主编. Goldman-Cecil医学. 26日艾德. Philadelphia, PA: Elsevier; 2020:chap 50.

邝的国家. 心血管磁共振成像. In: Libby P, Bonow RO, Mann DL, Tomaselli GF, Bhatt DL, Solomon SD, eds. Braunwald's 心 Disease: A Textbook of Cardiovascular Medicine. 12日艾德. Philadelphia, PA: Elsevier; 2022:chap 19.