Heart MRI
Definition
Heart
单个磁共振成像(MRI)图像称为切片. 这些图像可以存储在计算机上,也可以打印在胶片上. 一次考试会产生数十张甚至数百张图像.
The test may be done as part of a
Alternative Names
Magnetic resonance imaging - cardiac; Magnetic resonance imaging - heart; Nuclear magnetic resonance - cardiac; NMR - cardiac; MRI of the heart; Cardiomyopathy - MRI; Heart failure - MRI; Congenital heart disease - MRI
How the Test is Performed
你可能会被要求穿病号服或没有金属扣的衣服(如运动裤和t恤)。. 某些类型的金属会导致图像模糊或被强力磁铁吸引.
你将躺在一张狭窄的桌子上,桌子滑进一个像隧道一样的大管子.
Some exams require a special dye (contrast). 染料通常在检查前通过手或前臂的静脉注射. 这种染料可以帮助放射科十大赌博平台排行榜更清楚地看到某些区域. This is different from the dye used for a CT scan.
在核磁共振过程中,操作机器的人会在另一个房间看着你. 测试通常持续30到60分钟,但可能需要更长时间.
How to Prepare for the Test
你可能会被要求在扫描前4到6个小时不要吃或喝任何东西.
如果你害怕近距离空间(有幽闭恐惧症),告诉你的医疗保健提供者。. 十大赌博平台排行榜可能会给你开一种药,帮助你感到困倦和减少焦虑, or your provider may suggest an "open" MRI, in which the machine is not as close to the body.
Before the test, tell your provider if you have:
- Brain aneurysm clips
- Certain types of artificial heart valves
- Heart defibrillator or pacemaker
- Inner ear (cochlear) implants
- 肾脏疾病或透析(您可能无法接受对比)
- Recently placed artificial joints
- Certain types of vascular
stents - 过去曾接触过金属片(您可能需要检查眼睛中是否有金属片)
Because the MRI contains strong magnets, 金属物品不允许进入有核磁共振扫描仪的房间;
- 钢笔、小刀和眼镜可能会飞到房间的另一边.
- 珠宝、手表、信用卡和助听器等物品都可能被损坏.
- 别针、发夹、金属拉链和类似的金属物品会扭曲图像.
- 可拆卸的牙具应该在扫描前取出.
How the Test will Feel
A heart MRI exam causes no pain. 有些人在扫描仪内可能会感到焦虑. 如果你很难躺着不动或非常焦虑,你可能会服用药物来放松. 过多的运动可能会模糊MRI图像并导致错误.
桌子可能是硬的或冷的,但你可以要一条毯子或枕头. 机器开机时会发出巨大的砰砰声和嗡嗡声. You may be given ear plugs to help reduce the noise.
扫描仪内的对讲机可让您随时与操作检查的人员通话. 一些核磁共振扫描仪有电视和特殊的耳机来帮助打发时间.
没有恢复时间,除非需要镇静. (如果打了镇静剂,你需要有人开车送你回家.) After an MRI scan, you can resume your normal diet, activity, and medicines, unless your provider tells you otherwise.
Why the Test is Performed
核磁共振成像从多个角度提供心脏和血管的详细图像. Often, 当你做了超声心动图或心脏CT扫描后需要更多的信息时,可以使用它. 在某些情况下,核磁共振成像比CT扫描或其他测试更准确, but less accurate for others.
Heart MRI may be used to evaluate or diagnose:
- Heart muscle damage after a heart attack
- Birth defects of the heart
- Heart tumors and growths
- Weakening or other problems with the heart muscle
- Symptoms of heart failure
What Abnormal Results Mean
Abnormal results may be due to many things, including:
- Heart valve disorders
- Fluid in the sac-like covering around the heart (
pericardial effusion ) - Tumor of the blood vessels or around the heart
Atrial myxoma or another growth or tumor in the heart- 先天性心脏病(天生的心脏问题)
- Damage or death to the heart muscle, seen after a
heart attack - Inflammation of the heart muscle
- 异常物质对心肌的浸润
- 心肌衰弱,可由结节病或淀粉样变引起
Risks
There is no radiation involved in MRI. 在扫描过程中使用的磁场和无线电波尚未显示会造成任何显著的副作用.
对检查中使用的染料过敏反应是罕见的. 最常用的造影剂(染料)是钆. It is very safe. 操作机器的人会根据需要监测你的心率和呼吸. 有严重肾脏问题的人会出现罕见的并发症.
当人们没有从衣服上取下金属物品,或者当金属物品被其他人留在房间里时,他们就会在核磁共振成像仪中受到伤害.
MRI通常不推荐用于外伤性损伤.
核磁共振成像可能很昂贵,需要很长时间才能完成,而且对运动很敏感.
References
Kramer CM, Beller GA, Hagspiel KD. Noninvasive cardiac imaging. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 50.
Kwong RY. Cardiovascular magnetic resonance imaging. 见:Libby P, Bonow RO, Mann DL, Tomaselli GF, Bhatt DL, Solomon SD编. 布劳恩瓦尔德心脏病:心血管医学教科书. 12th ed. Philadelphia, PA: Elsevier; 2022:chap 19.
Review Date: 02/23/2022