ARRHYTHMOGENIC RIGHT-VENTRICULAR DISEASE - MR-IMAGING VS ANGIOGRAPHY

OBJECTIVE. Arrhythmogenic right ventricular disease (ARVD) is increasi ngly found in young adults with ventricular arrhythmias and is charact erized by ventricular tachycardia originating within the right ventric le and regional or diffuse abnormalities in the contraction of the rig ht ventricle. Until now, the gold standard for the detection of global and regional abnormalities of the right ventricular wall has been ang iography combined with biopsy. The purpose of the current study was to compare MR imaging with angiography for assessing the location and ex tent of morphologic and functional abnormalities in patients with ARVD . SUBJECTS AND METHODS. Electrocardiographically gated spin-echo and c ine gradient-echo MR imaging of the heart was performed in 36 consecut ive patients with biopsy-proved ARVD. Patients were prospectively sepa rated into two groups according to the results of invasive electrophys iologic tests (18 with inducible ventricular tachycardia during invasi ve electrophysiologic studies [ARVD 1] and 18 without inducible ventri cular tachycardia [ARVD 2]) and compared with 11 control subjects. Glo bal and regional morphology and function of the right ventricle were a ssessed with MR imaging, and those findings were compared with angiogr aphic findings. RESULTS. Right ventricular ejection fraction was signi ficantly lower in patients with ARVD 1 than in patients with ARVD 2 or in control subjects. Regional abnormalities of the right ventricular wall also were more pronounced in patients with ARVD 1 than in patient s with ARVD 2. Signal-intensity increases corresponding to fatty repla cement shown by biopsy were seen in 33% of patients with ARVD 1 and in 11% of patients with ARVD 2. Abnormal regions of the right ventricula r wall seen on MR images corresponded to angiographic findings in 86% of patients. Comparison with control subjects showed that patients wit h ARVD 1 had a significant delay in diastolic relaxation of the right ventricle. CONCLUSION. Our results show that MR imaging can be used to assess morphologic alteration, tissue abnormalities, and global as we ll as regional dysfunction of the right ventricle in patients with ARV D. It may become a useful clinical tool for diagnosing and grading ARV D and a worthy substitute for angiography and biopsy in the follow-up of patients with ARVD.