MYOCARDIAL GLUCOSE-METABOLISM IS DIFFERENT BETWEEN HYPERTROPHIC CARDIOMYOPATHY AND HYPERTENSIVE HEART-DISEASE ASSOCIATED WITH ASYMMETRICAL SEPTAL HYPERTROPHY

Myocardial glucose metabolism has been shown to be heterogeneous in pa tients with hypertrophic cardiomyopathy (HCM). We tested the hypothesi s that myocardial glucose metabolism differs between patients with HCM and those with hypertensive heart disease (HHD) associated with asymm etrical septal hypertrophy. We studied 12 patients with HCM, 7 HHD pat ients associated with asymmetrical septal hypertrophy using F-18 2-deo xyglucose (FDG) and positron emission tomography. We calculated % FDG fractional uptake in the interventricular septum and posterolateral wa ll. Heterogeneity of FDG uptake was evaluated by % interregional coeff icient of variation of FDG fractional uptake in each wall segment. In both the interventricular septum and posterolateral wall, % FDG fracti onal uptake was not significantly different between the two groups. Th e % interregional coefficient of variation for both interventricular s eptum (10.6 +/- 1.6 vs. 4.1 +/- 0.5, p < 0.01) and posterolateral wall (5.9 +/- 0.7 vs. 3.8 +/- 0.5, p < 0.05) was significantly larger in p atients with HCM than in HHD patients associated with asymmetrical sep tal hypertrophy. Echocardiography demonstrated that the degree of asym metrical septal hypertrophy was similar between the two groups. These results suggest that myocardial glucose metabolism may be more heterog eneous in patients with HCM compared to HHD patients associated with a symmetrical septal hypertrophy, although the left ventricular shape is similar. The difference in the heterogeneity might have resulted from differences in the pathogeneses of the two diseases. (C) 1997 Tohoku University Medical Press.