Department of Clinical Cardiology.
Pathology Unit, Division of Experimental Oncology.
J Cardiovasc Med (Hagerstown). 2022 Aug 1;23(8):505-512. doi: 10.2459/JCM.0000000000001347.
Chronic heart valve regurgitation induces left ventricular (LV) volume overload, leading to the development of hypertrophy and progressive dilatation of the ventricle to maintain physiological cardiac output. In order to prevent potential irreversible LV structural changes, the identification of the best timing for treatment is pivotal.
To assess the presence and extent of fibrosis in myocardial tissue in asymptomatic patients with valvular heart disease (VHD) and preserved LV dimensions and function undergoing cardiac surgery.
Thirty-nine patients were enrolled. Sixteen patients were affected by aortic or mitral regurgitation: they were all asymptomatic, undergoing valve surgery according to VHD European Society of Cardiology guidelines. Twenty-three patients with end-stage nonischemic dilated cardiomyopathy (DCM) and severe LV dysfunction undergoing cardiac surgery for implantation of a durable left ventricular assist device (LVAD) served as controls. During surgery, VHD patients underwent three myocardial biopsies at the level of the septum, the lateral wall and LV apex, while in LVAD patients the coring of the apex of the LV was used. For both groups, the tissue samples were analyzed on one section corresponding to the apical area. All slides were stained with hematoxylin and eosin and Masson's trichrome staining and further digitalized. The degree of fibrosis was then calculated as a percentage of the total area.
Of 39 patients, 23 met the inclusion criteria: 12 had mitral or aortic insufficiency with a preserved ejection fraction and 11 had idiopathic dilated cardiomyopathy. Quantitative analysis of apical sections revealed a myocardial fibrosis amount of 10 ± 6% in VHD patients, while in LVAD patients the mean apical myocardial fibrosis rate was 38 ± 9%. In VHD patients, fibrosis was also present in the lateral wall (9 ± 4%) and in the septum (9 ± 6%).
Our case series study highlights the presence of tissue remodeling with fibrosis in asymptomatic patients with VHD and preserved LV function. According to our results, myocardial fibrosis is present at an early stage of the disease, well before developing detectable LV dysfunction and symptoms. Since the relationship between the progressive magnitude of myocardial fibrosis and potential prognostic implications are not yet defined, further studies on this topic are warranted.
慢性心脏瓣膜反流导致左心室（LV）容量超负荷，导致心室肥大和进行性扩张，以维持生理心输出量。为了防止潜在的不可逆 LV 结构变化，确定最佳治疗时机至关重要。
评估无症状瓣膜性心脏病（VHD）患者和保留 LV 尺寸和功能的患者心肌组织中纤维化的存在和程度，这些患者正在接受心脏手术。
共纳入 39 名患者。16 名患者患有主动脉瓣或二尖瓣反流：他们均无症状，根据欧洲心脏病学会 VHD 指南行瓣膜手术。23 名患有终末期非缺血性扩张型心肌病（DCM）和严重 LV 功能障碍的患者正在接受心脏手术，植入耐用的左心室辅助装置（LVAD）作为对照组。手术过程中，VHD 患者在间隔、外侧壁和 LV 心尖处进行三次心肌活检，而在 LVAD 患者中则采用 LV 心尖的芯活检。对于两组患者，均对相应的心尖区域的一个切片进行组织样本分析。所有切片均用苏木精和伊红染色和 Masson 三色染色，并进一步数字化。然后计算纤维化程度占总面积的百分比。
39 名患者中有 23 名符合纳入标准：12 名患有二尖瓣或主动脉瓣关闭不全伴射血分数保留，11 名患有特发性扩张型心肌病。VHD 患者心尖节段的定量分析显示心肌纤维化量为 10%±6%，而 LVAD 患者平均心尖心肌纤维化率为 38%±9%。在 VHD 患者中，外侧壁（9%±4%）和间隔（9%±6%）也存在纤维化。
我们的病例系列研究强调了无症状 VHD 患者和保留 LV 功能患者存在组织重塑和纤维化。根据我们的结果，心肌纤维化在疾病的早期阶段就存在，远在出现可检测的 LV 功能障碍和症状之前。由于心肌纤维化的进展程度与潜在预后意义之间的关系尚未确定，因此需要对此主题进行进一步的研究。
