Due to the abnormal structure and function of the cardiac valves, cardiac valve disease gradually appears the expansion of left ventricular inner diameter and volume. When the left ventricular end-diastolic dimension and volume expand severely, it becomes a giant left ventricle. Surgical valve replacement is still one of the main treatment methods for this disease. The degree of postoperative ventricular recovery is closely related to perioperative mortality and long-term prognosis. However, the existing clinical preoperative assessment methods still cannot accurately predict the degree of postoperative left ventricular recovery and long-term prognosis of such patients, so it is difficult to determine the optimal operation timing and surgical methods for patients. Therefore, we reviewed the existing literature and discussed different evaluation methods of the giant left ventricle associated with valvular disease before surgery, so as to optimize the perioperative treatment of such patients, clarify the timing of surgery and improve the prognosis.
The fundamental reason why the organic lesions of chronic heart failure are difficult to reverse is ventricular remodeling. Myocardial fibrosis (MF) is an important pathological basis of ventricular remodeling. Its development process involves complex biological mechanisms and neuroendocrine system. Extracellular signal-regulated kinase (ERK) pathway is a classic pathway for the treatment of tumors. It is found that the inhibition of the ERK pathway can also slow down the progressive aggravation of MF. Therefore, exploring the mechanism of ERK pathway in MF may provide a new idea for the prevention and treatment of chronic heart failure. In this paper, the mechanism of ERK pathway in the occurrence and development of MF and its inhibition drugs were described, in order to provide evidence for the prevention and treatment of MF in chronic heart failure based on this pathway.
ObjectiveTo investigate the predictive value of right atrial myocardial fibrosis in the prognosis of isolated tricuspid regurgitation surgery after left heart valve surgery. MethodsThe patients who underwent tricuspid valvuloplasty by the same operator in Guangdong Provincial People's Hospital from April 2016 to August 2021 due to long-term isolated severe tricuspid regurgitation after left heart valve surgery were included in the study. According to the degree of right atrial myocardial fibrosis, the patients were divided into three groups: a mild group, a moderate group, and a severe group. The clinical data of these patients were compared and analyzed. ResultsA total of 75 patients were enrolled, including 16 males and 59 females with an average age of 57.0±8.4 years. There were 30 patients in the mild group, 29 patients in the moderate group and 16 patients in the severe group. In terms of the preoperative data, there were statistical differences in cardiac function grade, right atrial diameter, tricuspid incompetence area among the three groups (P<0.05). In terms of the postoperative data, there were statistical differences among the three groups in the cardiopulmonary bypass time, mechanical ventilation time, ICU monitoring time, complication rate and mortality (P<0.05). Further pairwise comparison showed that, compared with the mild group, the severe group had longer mechanical ventilation time (P=0.024), longer ICU monitoring time (P=0.003) and higher incidence of postoperative complications (P=0.024), while the moderate group had no statistical difference in all aspects (P>0.05); compared with the moderate group, the severe group had longer ICU monitoring time (P=0.021) and higher incidence of complications (P=0.006). ConclusionThe early outcome of tricuspid valvuloplasty in patients with isolated tricuspid regurgitation after left heart valve surgery with severe right atrial myocardial fibrosis is worse than that in the patients with mild and moderate fibrosis, suggesting that the degree of myocardial fibrosis in the right atrium can be a predictor of the effect of tricuspid regurgitation surgery and a judgement indicator of the surgery timing.
Objective To search for the key microRNAs (miRNAs) involved in myocardial fibrosis in hypertrophic cardiomyopathy, and to further explore the mechanisms involved in the regulation of myocardial fibrosis. MethodsForty-two patients with hypertrophic cardiomyopathy diagnosed and treated surgically in West China Hospital of Sichuan University from January 2014 to June 2018 were selected, including 29 males and 13 females, with a median age of 46 (15-69) years. In the myocardial tissue of patients with hypertrophic cardiomyopathy with different degrees of fibrosis, miRNAs with significantly different expression were screened and further verified at the cellular level. By regulating the expression of the target miRNAs, the expressions of fibrosis-related proteins and target genes were detected respectively. Finally, the target-binding relationship was verified by dual-luciferase reporter gene detection. ResultsmiR-484 was up-regulated in severely fibrotic myocardial tissue and activated cardiac fibroblasts. After cardiac fibroblasts were activated by TGF-β1, the expression of miR-484 was significantly up-regulated, the expression of fibrosis-related proteins (CollagenⅠ, α-SMA) increased, and the expression of the target gene HIPK1 decreased (P<0.05). After inhibiting the expression of miR-484 by transfection of miR-484 antagomir, the expression of fibrosis-related proteins decreased, while expression of HIPK1 was up-regulated (P<0.05). The detection of dual luciferase reporter gene showed that the luciferase activity of the transfected WT-miRNA-484 mimics group was lower than that of the control group (P<0.05). ConclusionmiR-484 is a pro-fibrotic miRNA that participates in the process of myocardial fibrosis by negatively regulating the expression of HIPK1. It can be used as a regulatory target to provide a therapeutic strategy for myocardial fibrosis.