Noninvasive detection of myocardial fibrosis in arrhythmogenic right ventricular cardiomyopathy using delayed-enhancement magnetic resonance imaging.
OBJECTIVE
We evaluated the role of myocardial delayed-enhancement (MDE) magnetic resonance imaging (MRI) for noninvasive detection of fibrosis in Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C).


BACKGROUND
Arrhythmogenic right ventricular dysplasia/cardiomyopathy is characterized by fibro-fatty replacement of the right ventricle (RV) leading to arrhythmias and RV failure. Endomyocardial biopsy can demonstrate fibro-fatty replacement of the RV myocardium; however, the test is invasive and carries a risk of perforation.


METHODS
Thirty consecutive patients were prospectively evaluated for ARVD/C. Magnetic resonance imaging was performed on a 1.5-T scanner. Ten minutes after intravenous administration of 0.2 mmol/kg of gadodiamide, MDE-MRI was obtained. Diagnosis of ARVD/C was based upon the Task Force criteria and did not include MRI findings.


RESULTS
Twelve (40%) of 30 patients met the Task Force criteria for ARVD/C. Eight (67%) of the 12 ARVD/C patients demonstrated increased signal on MDE-MRI in the RV compared with none (0%) of the 18 patients without ARVD/C (p <0.001). Endomyocardial biopsy was performed in 9 of the 12 ARVD/C patients. Of the nine patients, four had fibro-fatty changes consistent with the diagnosis of ARVD/C. Each of these patients had increased RV signal on MDE-MRI. None of the patients without ARVD/C had any abnormalities either on histopathology or on MDE-MRI. Electrophysiologic testing revealed inducible sustained ventricular tachycardia (VT) in six of the eight ARVD/C patients with delayed enhancement, compared with none of the ARVD/C patients without delayed enhancement (p=0.01).


CONCLUSIONS
Noninvasive detection of RV myocardial fibro-fatty changes in ARVD/C is possible by MDE-MRI. Magnetic resonance imaging findings had an excellent correlation with histopathology and predicted inducible VT on programmed electrical stimulation, suggesting a possible role in evaluation and diagnosis of patients with suspected ARVD/C.
Tandri
Harikrishna
H
Division of Cardiology, The Johns Hopkins University, Baltimore, MD 21287, USA.
Saranathan
Manoj
M
Rodriguez
E Rene
ER
Martinez
Claudia
C
Bomma
Chandra
C
Nasir
Khurram
K
Rosen
Boas
B
Lima
João A C
JA
Calkins
Hugh
H
Bluemke
David A
DA
D000293:Adolescent; D000328:Adult; D019571:Arrhythmogenic Right Ventricular Dysplasia / Q000473:pathology*; D002648:Child; D004558:Electric Stimulation; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D005355:Fibrosis; D019786:Gadolinium DTPA; D006352:Heart Ventricles / Q000473:pathology*; D006801:Humans; D007275:Injections, Intravenous; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D009206:Myocardium / Q000473:pathology*; D011446:Prospective Studies
C064925:gadodiamide; D019786:Gadolinium DTPA