Risk stratification in cardiomyopathies (dilated, hypertrophic, and arrhythmogenic cardiomyopathy) by cardiac magnetic resonance imaging

Abstract

Cardiac magnetic resonance imaging (CMR) is a non-invasive, multiplanar, and high spatial resolution imaging technique, which represents the current gold standard for the evaluation of biventricular volumes and function. Furthermore, unlike other methods, it has the great advantage of characterizing the myocardial tissue by identifying the presence of alterations, such as oedema and focal and diffuse fibrosis. In particular, the late gadolinium enhancement technique makes it possible to identify areas of focal fibrosis that often constitute the substrate for the triggering of threatening ventricular arrhythmias at the basis of sudden cardiac death. For this reason, the use of CMR in the study of cardiomyopathies has become of primary importance, both for the differential diagnosis and for patient risk stratification. In this brief review, the ability of CMR in prognostic stratification of patients with dilated, hypertrophic, and arrhythmogenic cardiomyopathy will be analysed. In particular, the role of CMR in the prediction of arrhythmic risk and in the decision-making process for the implantation of a cardiac defibrillator will be examined.

Keywords: Arrhythmic risk; Cardiac magnetic resonance; Implantable cardiac-defibrillator.

Figure 1

MRI images showing LGE in patients with cardiomyopathies: (A) NI-DCMP with areas of LGE at the level of the interventricular septum and inferolateral wall (arrows); (B) HCMP with large areas of interventricular septal LGE (arrows); (C) AC with LGE involving both ventricles (arrows). AC, arrhythmogenic cardiomyopathy; CMR, cardiac magnetic resonance; LGE, late gadolinium enhancement; NI-DCMP, non-ischaemic dilated cardiomyopathy.