title: Prediction of adverse cardiac events in dilated cardiomyopathy using cardiac T2* MRI and MIBG scintigraphy.
abstract: Iron deficiency and cardiac sympathetic impairment play a role in the worsening of heart failure, and these two conditions may be linked. The present study aimed to clarify the relationship between myocardial iron deficiency, cardiac sympathetic activity, and major adverse cardiac events (MACE) in patients with dilated cardiomyopathy (DCM). Cardiac T2* MRI for iron deficiency and (123)I-Metaiodobenzylguanidine (MIBG) imaging for cardiac sympathetic activity were performed in 46 patients with DCM. Myocardial T2* value (M-T2*) was calculated by fitting signal intensity data for mid-left ventricular septum to a decay curve using 3-Tesla scanner. (123)I-MIBG washout rate (MIBG-WR) was calculated using a polar-map technique with tomographic data. We analyze the ability of M-T2* and MIBG-WR to predict MACE. MIBG-WR and M-T2* were significantly greater in DCM patients with MACE than in patients without MACE. Receiver-operating-characteristics curve analysis showed that the optimal MIBG-WR and M-T2* thresholds of 35 % and 28.1 ms, and the two combination predict MACE with C-statics of 0.69, 0.73, and 0.82, respectively. Patients with MIBG-WR <35 % and M-T2* <28.1 ms had significantly lower event-free rates than those with MIBG-WR ≥35 % or M-T2* ≥28.1 ms (log-rank value = 4.35, p < 0.05). Cox hazard regression analysis showed that χ(2) and the hazard ratio were 3.99 and 2.15 for development of MACE in patients with MIBG-WR ≥35 % or M-T2* ≥28.1 ms (p < 0.05). Iron deficiency, expressed by a high M-T2*, and MIBG-WR were both independent predictors of MACE in patients with DCM. The two combination was a more powerful predictor of MACE than either parameter alone.
authors.affiliation: Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-Ku, Fukuoka City, Fukuoka, 812-8582, Japan, minagao@radiol.med.kyushu-u.ac.jp.
authors.forename: Michinobu
authors.initials: M
authors.lastname: Nagao
authors.forename: Shingo
authors.initials: S
authors.lastname: Baba
authors.forename: Masato
authors.initials: M
authors.lastname: Yonezawa
authors.forename: Yuzo
authors.initials: Y
authors.lastname: Yamasaki
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kamitani
authors.forename: Takuro
authors.initials: T
authors.lastname: Isoda
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kawanami
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Maruoka
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Kitamura
authors.forename: Kohtaro
authors.initials: K
authors.lastname: Abe
authors.forename: Taiki
authors.initials: T
authors.lastname: Higo
authors.forename: Kenji
authors.initials: K
authors.lastname: Sunagawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Honda
mesh_terms: D019797:3-Iodobenzylguanidine; D000328:Adult; D019540:Area Under Curve; D002311:Cardiomyopathy, Dilated / Q000150:complications* / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000378:metabolism; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging* / Q000294:innervation*; D006801:Humans; D000090463:Iron Deficiencies; D007564:Japan; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism*; D011237:Predictive Value of Tests; D012372:ROC Curve; D019275:Radiopharmaceuticals; D018570:Risk Assessment; D012307:Risk Factors; D013564:Sympathetic Nervous System / Q000000981:diagnostic imaging*; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine