123I-Metaiodobenzylguanidine myocardial scintigraphy in panic disorder.
Although autonomic function has been investigated in panic disorder, previous studies have not yet revealed a consistent autonomic change in this disease. The purpose of this study was to evaluate the cardiac sympathetic function in panic disorder using (123)I-metaiodobenzylguanidine ((123)I-MIBG).


METHODS
Myocardial imaging using (123)I-MIBG was performed on 9 patients with panic disorder (7 men, 2 women; mean age, 37.4 +/- 13.2 y) and 11 control subjects (11 men; mean age, 37.6 +/- 9.3 y). Early (30 min) and delayed (4 h) planar images were taken after the injection of 111 MBq (123)I-MIBG. The mean counts in the whole heart and the mediastinum were obtained from the early and delayed images to calculate the heart-to-mediastinum count ratios (H/M ratios) and the myocardial washout rate.


RESULTS
The (123)I-MIBG H/M ratios of the patients with panic disorder were 1.80 +/- 0.16 for the early images and 1.86 +/- 0.30 for the delayed images, which were significantly lower than those of the control subjects (2.15 +/- 0.15 [P = 0.001] and 2.26 +/- 0.21 [P = 0.009], respectively). The (123)I-MIBG washout rate from the heart in the patients with panic disorder (33.8% +/- 6.9%) was significantly higher than that in the control subjects (27.8% +/- 3.5%) (P = 0.02).


CONCLUSIONS
(123)I-MIBG myocardial scintigraphy demonstrated impairment of cardiac sympathetic function in panic disorder. The results suggest that (123)I-MIBG imaging could become a useful tool for analyzing the pathophysiology of panic disorder.
Tanabe
Yoshio
Y
Department of Radiology, Tottori University Hospital, Yonago, Japan. ytanabe-ttr@umin.ac.jp
Harada
Hiromi
H
Sugihara
Shuji
S
Ogawa
Toshihide
T
Inoue
Yuichi
Y
D000293:Adolescent; D000328:Adult; D001145:Arrhythmias, Cardiac / Q000000981:diagnostic imaging / Q000209:etiology / Q000378:metabolism; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging* / Q000294:innervation*; D006801:Humans; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism*; D016584:Panic Disorder / Q000150:complications / Q000000981:diagnostic imaging* / Q000378:metabolism*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013564:Sympathetic Nervous System / Q000000981:diagnostic imaging* / Q000378:metabolism*
D019275:Radiopharmaceuticals