Icariin improves cardiac function and remodeling via the TGF-ß1/Smad signaling pathway in rats following myocardial infarction.

BACKGROUND: Postinfarction cardiac remodeling presents a compensatory mechanism aimed at mitigating congestive heart failure. It is distinguished by progressive dilatation and hypertrophy of the ventricular chambers, fibrotic alterations, and prolonged apoptosis of cardiomyocytes. The primary objective of this study was to assess the effects of icariin on myocardial fibrosis and ventricular remodeling in rats subjected to myocardial infarction (MI). METHODS: Male Sprague‒Dawley (SD) rats were subjected to randomization and subsequently divided into distinct groups: the control group, the sham group (undergoing sham operation), the MI group (experiencing ligation of the left anterior descending artery), and the icariin group. Within the icariin group, rats were further categorized into three different dose groups based on the administered icariin dosage: the MI30 group (30 mg/kg/day), the MI60 group (60 mg/kg/day), and the MI120 group (120 mg/kg/day). Cardiac function evaluation was carried out using echocardiography. Histological examinations, including hematoxylin and eosin (HE) staining, Masson staining, and immunohistochemistry studies, were conducted 90 days after the occurrence of MI. Additionally, Western blotting was employed to assess TGF-ß1, p-Smad2, and p-Smad3 levels. RESULTS: The administration of icariin revealed a noteworthy enhancement in cardiac function among rats afflicted with left anterior descending coronary artery (LAD) ligation. In comparison to the icariin groups, the MI group exhibited reduced EF and FS, along with elevated LVEDD and LVESD. Furthermore, the cardiac fibrosis levels in the MI group rats exhibited a considerable increase compared to those in the icariin group. Notably, the levels of Collagen I, Collagen III, MMP2, and MMP9 were significantly higher in the MI group than in the icariin group, with evident distinctions. Moreover, the expression levels of TGF-ß, IL-13, p-Smad2, and p-Smad3 were notably upregulated in the MI group compared to the icariin group. CONCLUSIONS: In an experimental rat model of MI, the administration of icariin resulted in the amelioration of both cardiac function and remodeling processes, operating through the intricate TGF-ß1/Smad signaling pathway.

Cardiac resynchronization therapy (CRT) with right ventricular sense triggered left ventricular pacing benefits for the hemodynamics compared with standard CRT for chronic congestive heart failure: A cross-over study.

BACKGROUND: The aim of this study was to investigate the effect of cardiac resynchronization therapy (CRT) with right ventricular (RV) sense triggered left ventricular (LV) pacing for chronic heart failure (CHF). METHODS: Thirty patients who were eligible for the Class I indication of CRT were enrolled and the informed consents were signed. Left ventricular ejection fraction (LVEF), diastolic mitral flow velocity time integral (VTI), mitral regurgitation flow VTI, and aortic valve flow VTI were measured with GE Vivid 7 (GE Medical, Milwaukee, WI, USA) before and after CRT. The echocardiographic measurements and the average annual costs of the device use were compared. RESULTS: The duration of QRS complex, the length of time used for optimization, and the average annual cost of the device use under RV sense triggered LV pacing were significantly less than that under standard biventricular (BiV) pacing (p < 0.01), while the average battery lifetime was longer. Subgroup analysis showed that LVEF, diastolic mitral flow VTI, and aortic valve flow VTI under RV sense triggered LV pacing were greater than that under standard BiV pacing with right or LV pre-activation. The average battery lifetime was significantly longer and the average annual cost of the device use was less. The mitral regurgitation flow VTI under RV sense triggered LV pacing was less than that under standard BiV pacing with RV pre-activation. CONCLUSIONS: RV sense triggered LV provides benefits for CHF patients over standard CRT in terms of maintaining the physiological atrio-ventricular delay of atrio-ventricular node and improving the acute hemodynamic effects.

Initial experiences of maintaining atrioventricular intrinsic conduction during cardiac resynchronization therapy in non-responders.

BACKGROUND: Cardiac resynchronization therapy (CRT) is a major breakthrough in therapy for advanced heart failure patients; however, a number of key clinical research questions remain, perhaps most importantly the issue of why apparently suitable patients do not respond to CRT. METHODS: Seven patients, six males and one female, aged (56.43 +/- 6.13) years, all diagnosed with dilated cardiomyopathy, were included in this study. They were all non-responders to CRT who underwent routine optimization postoperatively, and received optimal drug therapy. On the basis of biventricular pacing, titrating various atrioventricular (AV) intervals were performed to get the true fusional QRS complexes composed of biventricular pacing and AV intrinsic conduction. Then, the effects of AV intrinsic conduction during CRT were evaluated. RESULTS: On the setting of AV intrinsic conduction during CRT, the true fusional QRS complexes were the narrowest, and all patients showed alleviation of symptoms, improvement of exercise tolerance, life quality and hemodynamic parameters during more than 6 months of follow-up. CONCLUSIONS: Titrating AV intervals to get the true fusional QRS complexes composed of biventricular pacing and AV intrinsic conduction will be beneficial for non-responders to CRT. Maintaining AV intrinsic conduction during CRT may decrease the rates of non-responders to CRT.

[The prospective study on the prognosis in patients with ventricular tachycardia or fibrillation treated with implantable automatic cardioverter defibrillator].

OBJECTIVE: To explore the effect of implantable automatic cardioverter defibrillator (ICD) on improvement of the prognosis of patients with ventricular tachycardia or fibrillation (VT/VF). To compare the advantages and disadvantages of ICD with antiarrhythmic drug, to select the best indication of ICD and review the protocol of the following-up of ICD patients, and present scientific evidence for the morebroad popularization who needs ICD in China. METHODS: In 99 selected patients who had the indication of class I, 27 patients were treated by ICD (ICD group), and 72 patients were not (non-ICD group). Patients in the two groups had the similar basic clinical characteristics. The incidence of syncope, CPR, and VF in ICD group were more common than those in non-ICD group. Patients in the two groups received same basic therapy. The total mortality rate and the incidence of cardiac events in two groups were compared in 3 months, 6 months, 12 months and 15 months. RESULTS: The total mortality rate and the incidence of cardiac events in ICD group were significantly lower than those in non-ICD group in the follow-up period. The mortality rate in ICD group is 0, and the mortality rate in non-ICD group is 20.8%. CONCLUSIONS: (1) ICD treatment can decrease the incidence of cardiac events of patients with high risk of sudden cardiac death (SCD), and improve their survival. (2) The key measures to insure the efficacy, safety, and cost-effectiveness of ICD treatment is: to select the patients correctly, to optimize the implanting process and the follow-up, and use rational assistant therapy.

A risk-predictive score for cardiogenic shock after acute myocardial infarction in Chinese patients.

BACKGROUND: Cardiogenic shock after acute myocardial infarction (AMI) remains a poor prognosis. Although numerous studies discussed the predictors of cardiogenic shock complicating AMI, the data in Chinese patients is still absent. The goal of this study is to develop a risk-predictive score for cardiogenic shock after AMI, among Chinese patients, so as to guide clinicians to prevent cardiogenic shock. METHODS: Patients with ST-segment elevated AMI were provided by two Chinese hospitals from 1994 to 2004. Baseline characteristics of each case were documented. Multivariable logistic regression modeling techniques were used to develop a model to predict the occurrence of cardiogenic shock within 72 h after admission. On the basis of the coefficients in the model, a risk score was developed for the probability of cardiogenic shock. To test its viability, another population, which was consistent with the original population, confirmed the scoring. RESULTS: Among 2,077 patients, 184 cases developed cardiogenic shock within 72 h. Age, gender, BMI, killip class, MI location, multivessel disease, previous MI, family history of CAD, and thrombolytic therapy were strong predictors for shock after AMI. A risk-predictive score for shock was developed. It predicted cardiogenic shock accurately in another Chinese population. CONCLUSIONS: A predictive model is developed in Chinese patients with AMI for the first time. It is based on some simple parameters, which can be easily obtained by clinicians. The risk score derived from the model can predict cardiogenic shock accurately.