OBJECTIVES: Manganese ions (Mn) enter cardiomyocytes via calcium (Ca) channels and enhance relaxation intracellularly. To prevent negative inotropy, new Mn-releasing contrast agents have been supplemented with high Ca. The study aim was to investigate how this affects cardiac function and magnetic resonance efficacy. MATERIALS AND METHODS: MnCl2 based contrast agents, manganese and manganese-calcium (Ca:Mn 10:1), were infused during 4 repeated washin-washout sequences in perfused guinea pig hearts. [Mn] were 10, 50, 100 and 500 microM. RESULTS: During washin, manganese depressed left ventricular developed pressure (LVDP) by 4, 9, 17, and 53% whereas manganese-calcium increased LVDP by 13, 18, 25, and 56%. After experiments, tissue Mn contents (nmol/g dry wt) were control <40, manganese 3720, and manganese-calcium 1620. T1 was reduced by 85-92% in Mn-enriched hearts. CONCLUSIONS: High Ca supplements to Mn-releasing contrast agents may be counterproductive by inducing a strong positive inotropic response and by reducing the magnetic resonance efficacy.
OBJECTIVES:Manganese ions (Mn) enter cardiomyocytes via calcium (Ca) channels and enhance relaxation intracellularly. To prevent negative inotropy, new Mn-releasing contrast agents have been supplemented with high Ca. The study aim was to investigate how this affects cardiac function and magnetic resonance efficacy. MATERIALS AND METHODS:MnCl2 based contrast agents, manganese and manganese-calcium (Ca:Mn 10:1), were infused during 4 repeated washin-washout sequences in perfused guinea pig hearts. [Mn] were 10, 50, 100 and 500 microM. RESULTS: During washin, manganesedepressed left ventricular developed pressure (LVDP) by 4, 9, 17, and 53% whereas manganese-calcium increased LVDP by 13, 18, 25, and 56%. After experiments, tissue Mn contents (nmol/g dry wt) were control <40, manganese 3720, and manganese-calcium 1620. T1 was reduced by 85-92% in Mn-enriched hearts. CONCLUSIONS: High Ca supplements to Mn-releasing contrast agents may be counterproductive by inducing a strong positive inotropic response and by reducing the magnetic resonance efficacy.
Authors: Karen C Briley-Saebo; Tuyen Hoang Nguyen; Alexander M Saeboe; Young-Seok Cho; Sung Kee Ryu; Eugenia R Volkova; Eugenia Volkava; Stephen Dickson; Gregor Leibundgut; Philipp Wiesner; Philipp Weisner; Simone Green; Florence Casanada; Yury I Miller; Walter Shaw; Joseph L Witztum; Zahi A Fayad; Sotirios Tsimikas Journal: J Am Coll Cardiol Date: 2012-02-07 Impact factor: 24.094
Authors: Christina L Brunnquell; Reinier Hernandez; Stephen A Graves; Ivy Smit-Oistad; Robert J Nickles; Weibo Cai; M Elizabeth Meyerand; Masatoshi Suzuki Journal: Contrast Media Mol Imaging Date: 2016-07-11 Impact factor: 3.161
Authors: Rajesh Dash; Jaehoon Chung; Fumiaki Ikeno; Annett Hahn-Windgassen; Yuka Matsuura; Mihoko V Bennett; Jennifer K Lyons; Tomohiko Teramoto; Robert C Robbins; Michael V McConnell; Alan C Yeung; Todd J Brinton; Phillip P Harnish; Phillip C Yang Journal: Circ Cardiovasc Imaging Date: 2011-06-30 Impact factor: 7.792
Authors: Nur Hayati Jasmin; May Zaw Thin; Robert D Johnson; Laurence H Jackson; Thomas A Roberts; Anna L David; Mark F Lythgoe; Philip C Yang; Sean M Davidson; Patrizia Camelliti; Daniel J Stuckey Journal: Adv Sci (Weinh) Date: 2021-04-02 Impact factor: 17.521