GATED BLOOD-POOL TOMOGRAPHY WITH FOURIER- ANALYSIS IN DIAGNOSIS OF ARRHYTHMOGENIC RIGHT-VENTRICULAR CARDIOMYOPATHY

ECG gated blood pool tomography has been performed in sixteen patients with right ventricular arrhythmias in whom the diagnosis of arrhythmo genic right ventricular cardiomyopathy was made based on the finding o f abnormalities on contrast angiography. They were compared both to co ntrol subjects and to patients with primary dilated cardiomyopathy. Th ick slices of ventricles were obtained throughout the cardiac cycle in three orthogonal planes : horizontal long axis and short axis thick s lices for analysis of right and left ventricular regional wall motion abnormalities and analysis of the spread of the contraction by means o f Fourier phase imaging, vertical long axis slices (one for each ventr icle) for ejection fractions, because of easy and reproducible determi nation of valvular planes and analysis of all right ventricular segmen ts, especially the pulmonary infundibulum. Five typical right ventricu lar abnormalities were seen : decreased ejection fraction (32 +/- 15% vs 55 +/- 3% in control; p < 0.001), increased diameter (ratio of righ t to left diameters = 1.2 +/- 0.3 vs 0.9 +/- 0.1; p < 0.01), global de layed contraction versus that of the left ventricle (22 +/- 20 degrees vs -2 +/- 6 %; p < 0.01), increased dispersion of contraction (32 +/- 16 degrees vs 13 +/- 4 degrees; p < 0.01) and presence of segments wi th decreased and/or delayed contraction. Right ventricular disease was observed in all the patients : localized form (56 %). diffused form ( 44 %). This method provides accurate functional data for diagnosis and follow-up of patients. in future, this wall motion evaluation method may replace planar nuclear angiography as myocardial SPECT have replac ed myocardial planar scintigraphy.