Department of Cardiology, Institute for Clinical and Experimental Medicine - IKEM, Prague, Czech Republic.
Physiol Res. 2013;62(3):247-55. doi: 10.33549/physiolres.932409. Epub 2013 Mar 14.
Atrial fibrosis is considered as the basis in the development of long-standing atrial fibrillation (AF). However, in advanced heart failure (HF), the independent role of fibrosis for AF development is less clear since HF itself leads to atrial scarring. Our study aimed to differentiate patients with AF from patients without AF in a population consisting of patients with advanced HF. Myocardial samples from the right atrial and the left ventricular wall were obtained during heart transplantation from the explanted hearts of 21 male patients with advanced HF. Long-standing AF was present in 10 of them and the remaining 11 patients served as sinus rhythm controls. Echocardiographic and hemodynamic measurements were recorded prior to heart transplantation. Collagen volume fraction (CVF), transforming growth factor-beta (TGF-beta), and connective tissue growth factor (CTGF) expression in myocardial specimens were assessed histologically and immunohistochemically. The groups were well matched according to age (51.9+/-8.8 vs. 51.3+/-9.3 y) and co-morbidities. The AF group had higher blood pressure in the right atrium (13.6+/-7.7 vs. 6.0+/-5.0 mmHg; p=0.02), larger left atrium diameter (56.1+/-7.7 vs. 50+/-5.1 mm; p=0.043), higher left atrium wall stress (18.1+/-2.1 vs. 16.1+/-1.7 kdynes/m(2); p=0.04), and longer duration of HF (5.0+/-2.9 vs. 2.0+/-1.6 y, p=0.008). There were no significant differences in CVF (p=0.12), in CTGF (p=0.60), and in TGF-beta expression (p=0.66) in the atrial myocardium between the two study groups. In conclusions, in advanced HF, atrial fibrosis expressed by CVF is invariably present regardless of occurrence of AF. In addition to atrial wall fibrosis, increased wall stress might contribute to AF development in long-standing AF.
心房纤维化被认为是长期持续性心房颤动（AF）发展的基础。然而，在晚期心力衰竭（HF）中，纤维化对 AF 发展的独立作用尚不清楚，因为 HF 本身会导致心房瘢痕形成。我们的研究旨在区分晚期 HF 患者中的 AF 患者和非 AF 患者。从接受心脏移植的 21 名男性晚期 HF 患者的心脏中获取右心房和左心室壁的心肌样本。其中 10 例存在长期 AF，其余 11 例窦性心律患者作为对照。在心脏移植前记录超声心动图和血液动力学测量值。通过组织学和免疫组织化学评估心肌标本中的胶原容积分数（CVF）、转化生长因子-β（TGF-β）和结缔组织生长因子（CTGF）的表达。两组在年龄（51.9+/-8.8 岁 vs. 51.3+/-9.3 岁）和合并症方面匹配良好。AF 组右心房血压较高（13.6+/-7.7 毫米汞柱 vs. 6.0+/-5.0 毫米汞柱；p=0.02），左心房直径较大（56.1+/-7.7 毫米 vs. 50+/-5.1 毫米；p=0.043），左心房壁应力较高（18.1+/-2.1 千达因/平方米 vs. 16.1+/-1.7 千达因/平方米；p=0.04），HF 持续时间较长（5.0+/-2.9 年 vs. 2.0+/-1.6 年，p=0.008）。两组心房心肌中的 CVF（p=0.12）、CTGF（p=0.60）和 TGF-β表达（p=0.66）无显著差异。总之，在晚期 HF 中，无论 AF 是否发生，CVF 表达的心房纤维化总是存在的。除了心房壁纤维化外，壁应力增加可能导致长期 AF 中 AF 的发展。
