心脏再同步治疗对非缺血性心肌病患者心肌胶原代谢的影响

Effects of Cardiac Resynchronization Therapy on Myocardial Collagen Metabolism in Non-ischemic Cardiomyopathy

目的:探讨心脏再同步治疗(CRT)对非缺血性心肌病(NICM)患者心肌胶原代谢的影响。方法:选取NICM患者76例,其中仅接受标准药物治疗者26例(Control组),接受CRT及标准药物治疗者50例(CRT组)。分别于基线、6月及12月检测外周血中心肌胶原代谢的标记物I型胶原羧基末端前肽(PICP)、I型胶原羧基端肽(ICTP)、基质金属蛋白酶-1(MMP-1)及组织金属基质蛋白酶抑制剂-1(TIMP-1)的变化。随访12月时左室射血分数(LVEF)值与基线比较净值增长5%定义为患者临床治疗有反应。结果:与基线比较,CRT组患者术后6月、12月PICP、ICTP及MMP-1均明显降低(P均<0.05);Control组患者术后6月、12月PICP、ICTP、MMP-1及TIMP-1与基线比较均未显示统计学差异。40例(53%)患者临床治疗有反应,其中CRT组33例(67%)明显高于Control组7例(27%),两组间具有统计学差异(P=0.01)。多因素logistics回归分析显示QRS间期,LVEF,PICP为临床反应预测因子。结论:CRT可以降低NICM患者的心肌胶原合成和分解,减缓心肌纤维化;检测患者基线PICP可预测患者治疗的临床反应,为NICM的临床诊治提供一定的参考价值。

Objective: To assess the effects of cardiac resynchronization therapy(CRT) on myocardial collagen metabolism among patients with non-ischemic cardiomyopathy(NICM). Methods: Seventy-six patients with NICM were enrolled in this study: 26 patients receiving standard medical therapy along(Control group), 50 patients undergoing CRT implantation and standard medical therapy(CRT group). Collagen metabolism were assessed from the carboxy-terminal propeptide of procollagen type I(PICP), carboxy-terminal telopeptide of type I collagen(ICTP), matrix metalloproteinase-1(MMP-1), and tissue inhibitor of matrix metalloproteinase-1(TIMP-1) in serum,respectively, at baseline, 6 months and 12 months follow-up. Patients were considered responders to therapy if they exhibited ≥5 %absolute increase in left ventricular ejection fraction(LVEF) at 12 months follow-up. Results: Compared with baseline, PICP, ICTP and MMP-1 were significantly lower in the CRT group at 6 months and 12 months(all P<0.05), whereas this effect was not evident among patients who were enrolled in control group. Forty patients(53 %) were classified as responders to therapy: 33 patients(67 %) in CRT group compared with 7 patients(27 %) in control group(P=0.01). On multivariate stepwise logistic regression analysis, QRS duration, LVEF and PICP were significant predictors of response to therapy. Conclusions: CRT reduces the synthesis and degradation of collagen in patients with NICM, and slows down myocardial fibrosis;the concentration of PICP in serum can predict the clinical response to treatment, which is valuable for the clinical diagnosis and treatment of NICM.