Cardiac I123-MIBG correlates better than ejection fraction with symptoms severity in systolic heart failure

Late gadolinium enhancement on cardiac magnetic resonance combined with 123I- metaiodobenzylguanidine scintigraphy strongly predicts long-term clinical outcome in patients with dilated cardiomyopathy

Late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) is limited in its ability to detect diffuse interstitial fibrosis, which is commonly found in idiopathic dilated cardiomyopathy (DCM). On the other hand, Washout rate (WR) by cardiac ¹²³I- metaiodobenzylguanidine (¹²³I-MIBG) scintigraphy which evaluates cardiac sympathetic nervous function, is a useful tool for predicting the prognosis in DCM. We investigated the predictive value of the combination of two different types of examinations, LGE on CMR and WR by ¹²³I-MIBG scintigraphy for outcomes in DCM compared with LGE alone. One-hundred forty-eight DCM patients underwent CMR and ¹²³I-MIBG scintigraphy. Patients were divided into 4 groups according to the presence or absence of LGE and WR cut-off value of 45% for predicting prognosis based on receiver operating characteristic curve analysis. Cardiac deaths, re-hospitalization for heart failure, implantation of a left ventricular assist device, and life-threatening ventricular arrhythmias were defined as clinical events. Forty-two DCM patients reached the clinical events during the median follow-up for 9.1 years (interquartile range, 8.0–9.2 years).Multivariable Cox regression analysis identified WR≥45%+LGE positive group as an independent predictor of cardiac events (HR 3.18, 95%CI 1.36–7.45, p = 0.008). Notably, there was no significance in the cardiac event-free survival rate between the WR<45%+LGE positive and WR≥45%+LGE negative groups (p = 0.89). The combination of WR by ¹²³I-MIBG scintigraphy and LGE on CMR, which evaluate different type of cardiac deterioration, serves as a stronger predictor of long-term outcomes in DCM patients than LGE alone.

Preoperative iodine-123 meta-iodobenzylguanidine imaging is a novel predictor of left ventricular reverse remodeling during treatment with a left ventricular assist device

Although left ventricular reverse remodeling (LVRR) is accompanied with an improved clinical course during LV assist device (LVAD) treatment, its preoperative prediction remains uncertain. Twenty-seven heart failure patients with dilated cardiomyopathy were enrolled in this study. Patients underwent (123)I-meta-iodobenzylguanidine (MIBG) scintigraphy before LVAD implantation, and were monitored at our institute from 2010 to 2014. This study investigated the prognostic value of preoperative (123)I-MIBG parameters for predicting postoperative LVRR. Of the preoperative variables studied, including (123)I-MIBG data, washout rate (WR) ≤ 39 % was the only significant, independent predictor of LVRR (defined as LV ejection fraction ≥35 % at 6 months post-LVAD implant using univariate and multivariate logistic regression analyses) (p = 0.036, odds ratio [OR]:14.45). Improved exercise capacity and more frequent opening of the native aortic valve, as well as lower B-type natriuretic peptide plasma levels, were observed in LVRR patients (p < 0.05 for all), although β-blocker doses were comparable with those of non-LVRR patients throughout the 6-month LVAD support period. In conclusion, preoperative (123)I-MIBG is a novel predictive tool of LVRR during LVAD support.