The contribution of myocardial sympathetic dysinnervation in the genesis of ventricular tachyarrhythmia. A study in patients with idiopathic dilated cardiomyopathy

In order to know the contribution of myocardial sympathetic dysinnervation in the genesis of ventricular tachyarrhythmia (VT), 123I-MIBG (meta-iodo-benzylguanidine) myocardial sympathetic nerve imaging was carried out in 52 patients with dilated cardiomyopathy (DCM) complicated with sustained VT (12 cases), non-sustained VT (18 cases) and VT(-) (22 cases). Myocardial SPECT at rest were done at 15 min after intravenous administration of 201Tl (111 MBq), and at 15 and 4 hr after intravenous administration of 123I-MIBG (111 MBq) with Toshiba GCA501 A/HG. Defects were scored for each image and difference of total defect scores (dTDS) between 201Tl and 123I was calculated. Echocardiography was also performed. dTDS was found significantly higher in sustained and non- sustained VT cases than VT(-) and thus myocardial sympathetic dysfunction or denervation was thought highly correlated with the genesis of VT in DCM. (K.H.)