Cardiac magnetic resonance for prognostic assessment: present applications and future directions

Abstract

Cardiac magnetic resonance is increasingly used in clinical practice for both diagnostic and prognostic purposes. In the field of ischemic heart disease, perfusion imaging permits the assessment of ischemia, which is strongly related to future cardiac events and mortality. Late gadolinium enhancement is also associated with the prognosis and can be used as a marker of functional recovery. Cardiac magnetic resonance also permits the detection of microvascular obstruction and infarct hemorrhage, both related to an adverse outcome. In non-ischemic heart disease, the presence of late gadolinium enhancement is linked to mortality and hard events. Finally, coronary angiography, as well as new techniques, such as T1 mapping, may also have a prognostic role.

Keywords::

• cardiovascular magnetic resonance
• late gadolinium enhancement
• perfusion
• prognosis
• risk assessment

Acknowledgement

The authors thank Anne Gale for editorial assistance in the preparation of the manuscript.

Financial & competing interests disclosure

A Doltra is supported by a research grant from the European Society of Cardiology. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Cardiac magnetic resonance (CMR) is a highly reproducible technique for the assessment of ventricular volumes, mass and function.

• The presence and extent of late gadolinium enhancement (LGE) in patients with ischemic cardiomyopathy are predictive of LV function and events at follow-up. The extent of LGE in the myocardial wall is strongly related with the probability of functional improvement: the larger the extent, the lower the probability of improvement in contractility for a particular segment.

• In nonischemic heart disease (dilated cardiomyopathy, hypertrophic cardiomyopathy), LGE is associated with a higher rate of cardiac death and appropriate ICD discharge. An abnormal CMR scan in patients with myocarditis is also predictive of a worse outcome.

• Stress CMR is a good technique to establish prognosis in coronary artery disease patients. The presence of inducible ischemia is a strong independent predictor of future events; the absence of inducible ischemia, on the other hand, is associated with an excellent outcome (annual death rate <1%).

• Stress CMR and LGE provide independent and additive prognostic information.

• T2 imaging can detect the presence of edema. In the setting of an acute myocardial infarction, T2 imaging permits calculation of the salvaged area, which is also related to future events and ventricular adverse remodeling.

• T1 mapping and extracellular volume fraction quantification are new techniques that may overcome LGE limitations for assessing interstitial and diffuse fibrosis. Some initial data suggest that they may also offer prognostic information, although more studies are needed.

• Coronary CMR angiography can be used to assess the coronary arteries and has been validated against invasive angiography. The diagnostic performance of coronary CMR angiography seems to be nonsignificantly inferior to that of coronary computed tomography angiography. Some initial data suggest its utility to predict events in patients with suspected or known coronary artery disease.

• Four-dimensional flow CMR permits the evaluation of flow characteristics and the impact of flow on the arterial wall. This technique can be used to study the pathophysiological mechanisms of valvular and vascular diseases.

Notes