ABC | Volume 110, Nº6, June 2018

Original Article Zhen et al AAC leads to obvious CH using 0.45 mm needle Arq Bras Cardiol. 2018; 110(6):568-576 1. Zhao CZ, Zhao XM, Yang J, Mou Y, Chen B, Wu HD, et al. Inhibition of farnesyl pyrophosphate synthase improves pressure overload induced chronic cardiac remodeling. Sci Rep. 2016Dec 23;6:39186. doi: 10.1038/ srep39186. 2. Frey N, Olson EN. Cardiac hypertrophy: the good, the bad, and the ugly. Annu Rev Physiol. 2003;65:45-79. doi: 10.1146/annurev. physiol.65.092101.142243. 3. Alla F, Zannad F, Filippatos G. Epidemiology of acute heart failure syndromes. Heart Fail Rev. 2007;12(2):91-5. doi: 10.1007/s10741-007-9009-2. 4. Sato N, Lam CS, Teerlink JR, Greenberg BH, Tsutsui H, Oh BH, et al. Evaluating the efficacy, safety, and tolerability of serelaxin when added to standard therapy in Asian patients with acute heart failure: design and rationale of RELAX-AHF-ASIA trial. J Card Fail. 2017;23(1):63-71. doi: 10.1016/j.cardfail.2016.10.016. 5. 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Acute heart failure with cardiomyocyte atrophy induced in adult mice by ablation of cardiac myosin light chain kinase. Cardiovasc Res. 2016;111(1):34-43. doi: 10.1093/cvr/cvw069. 9. Foppa M, Arora G, Gona P, Ashrafi A, Salton CJ, Yeon SB, et al. Right ventricular volumes and systolic function by cardiac magnetic resonance and the impact of sex, age, and obesity in a longitudinally followed cohort free of pulmonary and cardiovascular disease: the Framingham Heart Study. Circ Cardiovasc Imaging. 2016;9(3):e003810. doi: 10.1161/ CIRCIMAGING.115.003810. References Normally, with the PO-induced CH model, thinner needles creates more severe aortic stenosis and lead to more pronounced CH, and vice versa. However, we observed an interesting phenomenon: the CH level of the 18 g/0.45 mm group was abnormally significantly higher than that of the 18 g/0.40 mm group (18-g mice in Table 3). Regarding the analysis of BW data with AAC (Table 6), the changes in BW in 18-g mice during weeks 0 to 8 were significantly higher than those for the 22-g and 26-g mice, indicating that 18-g mice have greater potential for physical development after surgery and that physical development is often accompanied by organ development. 17 Therefore, the heart of 18-g mice also has greater development potential. For the same weight level, the BWchange of the 18 g/0.45 mm group during weeks 0 to 8 was significantly higher than that of the 18 g/0.40 mm group (BW change in Table 7). As mentioned, BW is positively related to CO; therefore, perhaps the greater ligation limited CO in the 18 g/0.40 mm group, which also limited physical development and organ development, including development of the heart. At the end of week 8, there was no significant difference in BW for the 18g/0.45mm group and 18g/sham groups; both had significantly higher BW than the 18 g/0.40 mm group (BW at week 8 in Table 7). The 0.45-mm needle had no obvious limits in18-g mice, but the BWadvantage for the 18 g/0.45 mm group compared to the 18 g/0.40mm group depends on greater CO and requires more hypertrophic myocardium for support. So, to establish CH models for AAC in mice that have developmental potential, such as 18-g mice, there may be a special ligating intensity region that can cause more obvious CH than the two adjacent regions. However, this phenomenonmust comprise multiple factors and is worth further study. Conclusion We established CHmodels using 4 ligation needle sizes and 3 weights for mice. Data showed that both of 0.45-mm and 0.50-mm needles lead to CH. However, 0.45mm needle brings more effective model and causes obvious CH in 18-g mice. Author contributions Conception and design of the research: Zhen J, Yiming N; Acquisition of data: Zhen J, Chen Z, Hongfei X, Dongdong J; Analysis and interpretation of the data: Zhen J, Chen Z; Statistical analysis: Zhen J, Chen Z, Peng T; Obtaining financing: Hongfei X; Writing of the manuscript: Zhen J, Dongdong J; Critical revision of the manuscript for intellectual content: Armah MA, Weidong L, Liang M. Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding This study was funded by The National Natural Science Foundation of China (number 81570343). Study Association This article is part of the thesis of Doctoral submitted by Zhen Jia, from Zhejiang University. Ethics approval and consent to participate This study was approved by the Ethics Committee of the First Affiliated Hospital, College of Medicine, Zhejiang University under the protocol number 2014-17. All the procedures in this study were in accordance with the 1975 Helsinki Declaration, updated in 2013. Informed consent was obtained from all participants included in the study. 574