The effects of hyperthyroidism on MIBG uptakes in the human heart--preliminary report.
Twelve cases of hyperthyroidism with cardiac manifestations (4 males, 8 females, ages: 20 to 70 years) and 12 normal controls of euthyroidism (6 males, 6 females, ages: 27 to 70 years) were included in our study. Each case accepted an I.V. injection of I-131 MIBG (I.R.E., Belgium) with 0.5mCi/1.7m2 of body surface area. The 24 and 48 hr imagings of the anterior chest, including total heart and lungs, were used to estimate cardiac sympathetic nerve innervation by the following formula: H/L = (the mean counts of pixels in the regions of interest (ROI) over the heart)/(the mean counts of pixels in the ROI over the lungs). The results showed that the 24 and 48 hr H/L values in euthyroidism were a little higher than those in hyperthyroidism, but the differences were not significant by a Wilcoxon rank sum test. The correlation between H/L and 24 hr I-131 thyroid uptake in patients with hyperthyroidism were also evaluated and the results showed no significant correlation between the H/L and uptake. In conclusion, we consider that the clinical manifestations concerning the heart in hyperthyroidism may not totally depend on the effects of increased cardiac sympathetic nerve innervation.
Kao
C H
CH
Department of Nuclear Medicine, Taichung Veterans General Hospital, Taiwan, Republic of China.
Wang
S J
SJ
Liao
S Q
SQ
Hsu
C Y
CY
Lin
W Y
WY
D019797:3-Iodobenzylguanidine; D000328:Adult; D000368:Aged; D005260:Female; D006321:Heart / Q000294:innervation*; D006801:Humans; D006980:Hyperthyroidism / Q000503:physiopathology*; D007462:Iodobenzenes / Q000493:pharmacokinetics*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D013565:Sympatholytics / Q000493:pharmacokinetics*
D007462:Iodobenzenes; D013565:Sympatholytics; D019797:3-Iodobenzylguanidine