Cardiac MRI

Changed by Mark Thurston, 23 Sep 2018

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Cardiac MRI consists of using MRI to study heart anatomy, physiology, and pathology.

Advantages

The main advantages ofIn comparison to other techniques, cardiac MRI in comparison with other techniques areoffers:

  • better definition ofimproved soft tissuestissue definition
  • use of different typesprotocol can be tailored to likely differential diagnoses
    • a large number of sequences improves diagnostic accuracyare available
    • dynamic imaging provides functional assessment
  • no ionising radiation

Limitations

The main limitation of MRI, comparedMRI is generally inferior to cardiac CT, is the poorer for evaluation of the coronary arteries.

In addition, cardiacCardiac MRI employs somecan be technically challenging. In particular, a comprehensive understanding of cardiac imaging planes is required for scan planning.

Imaging

Dark blood Imaging

Dark blood imaging involvesmay be based on spin echo or steady-state free precession sequences. Its main advantage is a The fast acquisition thattime of the sequences minimises respiratory and cardiac movement artefacts. Its main issue is However, a low signal/noise ratio and, therefore, a deficientresults in inferior spatial resolution. 

These can be T1, T2, or proton density weighted sequences:

  • T1 weighted sequences achieve better anatomic definition
  • T2 and PD weighted sequences reach better tissue characterization
White blood Imaging

White blood imaging involves gradient echo sequences and steady-state free precession MRI (SSFP). In practice, the difference between the two is that SSFP is less vulnerable to the T2* effect.

The main advantage of white blood imaging is its fast acquisition. It can obtain movement sequences and allows studying cardiac function and movement.

Flux quantification sequences

The most usual sequence of this group is phase contrast imaging. It encodes flux direction and speed, similarly to CSF flow studies.

Inversion Recovery sequences

These imaging techniques use additional 180º pulses to null signal from blood and other tissues, and, therefore, improve contrast.

The most used sequence is STIR.

Contrast-enhanced techniques

Perfusion imaging (also known as first-pass images)

These are T1 weighted, gradient-echo sequences. Image acquisition is performed 3 minutes after gadolinium contrast administration. If there is a hypoenhanced area, this implies a zone of myocardial infarction that is non-viable.

Viability study delayed (also known as myocardial enhancement study)

These are T1 weighted, gradient-echo sequences. Image acquisition is performed 10 minutes after gadolinium contrast administration. 

Focal myocardial fibrosis has a delayed gadolinium contrast wash out. So hyperenhancement indicates a myocardial scar, thus an evolved myocardial infarction.

Usually, an extra inversion pulse is used to improve contrast between fibrosis and the surrounding myocardium.

  • -<p><strong>Cardiac MRI</strong> consists of using MRI to study heart anatomy, physiology and pathology.</p><h4>Advantages</h4><p>The main advantages of cardiac MRI in comparison with other techniques are:</p><ul>
  • -<li>better definition of soft tissues</li>
  • -<li>use of different types of sequences improves diagnostic accuracy</li>
  • -<li>no ionising radiation<ul><li>some <a href="/articles/mri-safety">safety issues</a> still require consideration</li></ul>
  • +<p><strong>Cardiac MRI</strong> consists of using MRI to study heart anatomy, physiology, and pathology.</p><h4>Advantages</h4><p>In comparison to other techniques, cardiac MRI offers:</p><ul>
  • +<li>improved soft tissue definition</li>
  • +<li>protocol can be tailored to likely differential diagnoses<ul>
  • +<li>a large number of sequences are available</li>
  • +<li>dynamic imaging provides functional assessment</li>
  • +</ul>
  • -</ul><h4>Limitations</h4><p>The main limitation of MRI, compared to <a href="/articles/cardiac-ct-1">cardiac CT</a>, is the poorer evaluation of the coronary arteries.</p><p>In addition, cardiac MRI employs some particular <a href="/cases/cardiac-mri-standard-imaging-planes-1">imaging planes</a>.</p><h4>Imaging</h4><h5>Dark blood Imaging</h5><p>Dark blood imaging involves <a href="/articles/spin-echo-sequences">spin echo sequences</a>. Its main advantage is a fast acquisition that minimises respiratory and cardiac movement artefacts. Its main issue is a low signal/noise ratio and, therefore, a deficient spatial resolution. </p><p>These can be T1, T2, or proton density weighted sequences:</p><ul>
  • +<li>no ionising radiation<ul><li>
  • +<a href="/articles/mri-safety">MRI safety</a> still requires consideration</li></ul>
  • +</li>
  • +</ul><h4>Limitations</h4><p>MRI is generally inferior to <a href="/articles/cardiac-ct-1">cardiac CT</a> for evaluation of the <a href="/articles/coronary-arteries">coronary arteries</a>.</p><p>Cardiac MRI can be technically challenging. In particular, a comprehensive understanding of <a href="/articles/cardiac-imaging-planes">cardiac imaging planes</a> is required for scan planning.</p><h4>Imaging</h4><h5>Dark blood Imaging</h5><p>Dark blood imaging may be based on <a href="/articles/spin-echo-sequences">spin echo</a> or <a title="SSFP" href="/articles/steady-state-free-precession-mri-2">steady-state free precession</a> sequences. The fast acquisition time of the sequences minimises respiratory and cardiac movement artefacts. However, a low signal/noise ratio results in inferior spatial resolution. </p><p>These can be T1, T2, or proton density weighted sequences:</p><ul>

References changed:

  • 1. Ginat DT, Fong MW, Tuttle DJ, et al. Cardiac imaging: Part 1, MR pulse sequences, imaging planes, and basic anatomy. (2011) AJR. American journal of roentgenology. 197 (4): 808-15. <a href="https://doi.org/10.2214/AJR.10.7231">doi:10.2214/AJR.10.7231</a> - <a href="https://www.ncbi.nlm.nih.gov/pubmed/21940567">Pubmed</a> <span class="ref_v4"></span>
  • 2. Gaba RC, Carlos RC, Weadock WJ,et al. Cardiovascular MR imaging: technique optimization and detection of disease in clinical practice. (2002) Radiographics : a review publication of the Radiological Society of North America, Inc. 22 (6): e6. <a href="https://doi.org/10.1148/rg.e6">doi:10.1148/rg.e6</a> - <a href="https://www.ncbi.nlm.nih.gov/pubmed/12432131">Pubmed</a> <span class="ref_v4"></span>
  • 3. Reeder SB, Du YP, Lima JA, Bluemke DA. Advanced cardiac MR imaging of ischemic heart disease. (2001) Radiographics : a review publication of the Radiological Society of North America, Inc. 21 (4): 1047-74. <a href="https://doi.org/10.1148/radiographics.21.4.g01jl281047">doi:10.1148/radiographics.21.4.g01jl281047</a> - <a href="https://www.ncbi.nlm.nih.gov/pubmed/11452080">Pubmed</a> <span class="ref_v4"></span>
  • 3. Hernández C, Zudaire B, Castaño S, Azcárate P, Villanueva A, Bastarrika G. Principios básicos de resonancia magnética cardiovascular (RMC): secuencias, planos de adquisición y protocolo de estudio. Anales del Sistema Sanitario de Navarra. 2007 Dec;30(3):405–18.
  • 5. Alberto San Román J, Soler Fernández R, Rodríguez García E, Fernández-Avilés F. Conocimientos básicos necesarios para realizar resonancia magnética en cardiología. Revista Española de Cardiologia. 2006 Jun;6(Supl.E):7–14.
  • 1. Ginat DT, Fong MW, Tuttle DJ, Hobbs SK, Vyas RC. Cardiac Imaging: Part 1, MR Pulse Sequences, Imaging Planes, and Basic Anatomy. American Journal of Roentgenology. 2011 Oct 1;197(4):808–15.
  • 2. Gaba RC, Carlos RC, Weadock WJ, Reddy GP, Sneider MB, Cascade PN. Cardiovascular MR Imaging: Technique Optimization and Detection of Disease in Clinical Practice. RadioGraphics. 2002 Nov 1;22(6):e6–e6.
  • 4. Reeder SB, Du YP, Lima JAC, Bluemke DA. Advanced Cardiac MR Imaging of Ischemic Heart Disease. RadioGraphics. 2001 Jul 1;21(4):1047–74.

Updates to Synonym Attributes

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