[Clinical significance of 123I-MIBG myocardial scintigraphy in patients with hypertrophic cardiomyopathy].

We studied the abnormality of myocardial sympathetic nervous system in patients with hypertrophic cardiomyopathy using 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy in comparison with the parameters of other clinical examinations. In 50 patients with HCM, the heart to mediastinum 123I-MIBG uptake ratio (H/M) was significantly low and washout rate (WR) of 123I-MIBG was significantly high respectively compared with normal subjects (n = 8). H/M was negatively correlated with serum norepinephrine level, wall thickness of left ventricle, left ventricular mass index, left ventricular end diastolic pressure respectively, and WR was positively correlated with those parameters respectively. On the other hand, LF/HF calculated by spectral analysis in holter electrocardiogram was positively correlated with H/M, and negatively correlated with WR. In HCM, H/M in patients with subjective symptoms was significantly lower than that without subjective symptoms, and WR in patients with paroxysmal atrial fibrillation was significantly higher than that without paroxysmal atrial fibrillation. This study revealed that H/M and WR reflected the severity and the difference of disease type in HCM. In conclusion, 123I-MIBG contributes to evaluating more details in diagnosis and pathophysiology of HCM.