Quantification of fatty tissue mass by magnetic resonance imaging in arrhythmogenic right ventricular dysplasia.

INTRODUCTION

Arrhythmogenic right ventricular dysplasia (ARVD) is a heart muscle disorder in which the pathological substrate is a fatty or fibro-fatty replacement of the right ventricular (RV) myocardium.

METHODS AND RESULTS

Magnetic resonance imaging (MRI) studies were performed in 10 patients with arrhythmogenic right ventricular dysplasia and in 24 matched controls in order to assess right ventricular epicardial/intramyocardial fatty tissue mass, RV myocardial mass, and RV functional parameters. Functional abnormalities were found in all ARVD cases. Patients with ARVD showed increased fatty tissue compared to controls (8.2 +/- 4 g vs. 2.0 +/- 1.0 g; P = 0.001), whereas no significant differences were found in RV myocardial mass (29.5 +/- 9.2 g vs. 23.2 +/- 6.7 g; P = NS). A correlation coefficient between 0.87 and 0.97 was found for repeated measurements.

CONCLUSION

Quantification of fatty tissue with MRI is feasible and constitutes an objective method for differentiating normal from pathological conditions. This approach may lead to a complete diagnostic assessment of ARVD with the potential application for monitoring the evolution of the disease.