The role of cardiac magnetic resonance imaging in the diagnostic work-up of patients with cardiomyopathies

Abstract

Cardiac magnetic resonance imaging is a noninvasive imaging modality that gives us a better look at cardiac function and morphology. It is highly accurate and reproducible.Cardiovascular diseases are the leading cause of mortality worldwide. Cardiomyopathy is a myocardial disorder in which the heart muscle is structurally and functionally abnormal, in the absence of coronary artery disease, hypertension, valvular disease, and congenital heart disease sufficient to cause the observed myocardial abnormality. Considering that most cardiomyopathies are often asymptomatic and their first manifestation is sometimes sudden cardiac death, the need for accurate and timely diagnosis is obvious. Early management can extend the patients’ life expectancy and provide a better quality of life. Today cardiac magnetic resonance is an integral part of diagnosing and monitoring patients with cardiomyopathies. Besides diagnosing and monitoring patients, cardiac magnetic resonance can provide aetiological assessment and prognosis.Multiple imaging techniques are used and are all based on principles of nuclear magnetic resonance. Steady-state free precession cine imaging allows dynamic imaging of cardiac wall motion with superior blood-endocardial border definition. Gadolinium based contrast agents highlight areas of myocardial fibrosis and necrosis, and based on distribution of enhancing areas it is possible to determine the aetiology of cardiomiopathy. T2-weighted fat-suppressed short-tau inversion recovery imaging shows increased signal in the presence of myocardial oedema. T1 and T2 mapping provide a pixel-by-pixel method of quantifying T1 and T2 relaxation time, respectively. T2* mapping allows quantification of myocardial tissue iron levels.This review paper explains modern cardiac magnetic resonance imaging modalities and their role in the diagnostic work-up of patients with cardiomyopathy.

Keywords

• cardiomyopathies – diagnostic imaging
• patology
• physiopathology; magnetic resonance imaging – methods; gadolinium; myocardium – pathology; image processing