DETECTION OF IMPAIRED FATTY-ACID METABOLISM AND DYSKINESIS IN HYPERTROPHIC CARDIOMYOPATHY WITH IODINE-123-BMIPP

Metabolic imaging using I-123-labeled 15- (p-iodophenyl)-3-R,S-methylp entadecanoic acid (BMIPP) and Fourier phase analysis of gated blood-po ol data were performed in a 60-yr-old woman with idiopathic hypertroph ic cardiomyopathy. Dyskinetic wall motion was identified as a markedly delayed phase angle in the left ventricular apex, which was well perf used but highly hypertrophied like other ventricular segments. Fatty a cid imaging, however, clearly demonstrated highly reduced activities i n the apex, although there were no abnormalities in regional systolic function or in (TI)-T-201 uptake in other hypertrophied regions. Contr ast left ventriculography revealed a midventricular collapse of the le ft ventricle at end-systole due to markedly hypertrophied ventricular walls and dyskinesis at the apex. Thus, dyskinetic wall motion in the apex closely correlated not only with cardiac hypertrophy but also wit h impaired fatty acid uptake. These findings were unrelated to the myo cardial perfusion state per se. Fatty acid imaging using BMIPP may con tribute to the detection of myocyte degeneration not visible using con ventional imaging modalities. It may also provide etiological informat ion on regional dysfunction in hypertrophic cardiomyopathy.