WITHDRAWN: Beneficial effect of endo-CRT might be mediated by more improvement of SERCA2A in chronic dyssynchronous canine heart failure models

// Hongyun Chen 1 , Shuang Liu 2 , Zhihong Zong 3 , Cuiting Zhao 2 , Guangyuan Li 2 , Yonghuai Wang 2 , Guoxian Qi 1 , Jun Yang 2 and Chunyan Ma 2 1 Department of Geriatric Cardiology, First Hospital of China Medical University, Shenyang, Liaoning, China 2 Department of Cardiovascular Ultrasound, First Hospital of China Medical University, Shenyang, Liaoning, China 3 China Medical University, Shenyang, Liaoning, China Correspondence to: Chunyan Ma, email: cmu1h_mcy@126.com Keywords: cardiac resynchronization therapy (CRT); SERCA2A; endo-CRT; epi-CRT; dyssynchronous heart failure Received: March 29, 2017      Accepted: December 29, 2017      Published: January 02, 2018 ABSTRACT The aims of the present study were to compare the effects of endocardial cardiac resynchronization therapy (endo-CRT) and epicardial CRT (epi-CRT) on cardiac contractile function and to delineate the underlying molecular mechanisms. Twenty-four adult mongrel canines were divided into four groups: sham-operation control group (CT, n = 6), dyssynchronous heart failure (DHF) group ( n = 6), epi-CRT group ( n = 6), and endo-CRT group ( n = 6). The global and local left ventricle (LV) systolic function, dyssynchrony and myocardium calcium handling molecular mRNA and protein levels were measured. Compared to CT group, we found the global and local LV function, dyssynchrony and SERCA2A decreased in DHF group and increased in CRT groups, particularly in endo-CRT group at LV lateral wall (pacing site). Therefore, endo-CRT appears to be an effective procedure in the treatment of DHF, which might be mediated by upregulating the mRNA and protein expression of SERCA2A in the LV at the pacing and remote site.