Desmoplakin and clinical manifestations of desmoplakin cardiomyopathy / 中华医学杂志(英文版)

Desmoplakin (DSP), encoded by the DSP gene, is the main desmosome component and is abundant in the myocardial tissue. There are three DSP isoforms that assume the role of supporting structural stability through intercellular adhesion. It has been found that DSP regulates the transcription of adipogenic and fibrogenic genes, and maintains appropriate electrical conductivity by regulating gap junctions and ion channels. DSP is essential for normal myocardial development and the maintenance of its structural functions. Studies have suggested that DSP gene mutations are associated with a variety of hereditary cardiomyopathy, such as arrhythmia cardiomyopathy, dilated cardiomyopathy (DCM), left ventricular noncompaction, and is also closely associated with the Carvajal syndrome, Naxos disease, and erythro-keratodermia-cardiomyopathy syndrome with skin and heart damage. The structure and function of DSP, as well as the clinical manifestations of DSP-related cardiomyopathy were reviewed in this article.

Feasibility and safety of new simplified left bundle branch area pacing via nine-partition method / 中华心血管病杂志

Objective: To investigate the efficacy and safety of left bundle branch area pacing (LBBaP) with the new simplified approach (nine-partition method). Methods: A total of 118 patients with clinical indications and received pacemaker implantation from December 1, 2018 to December 31, 2019 in Beijing Anzhen Hospital were enrolled. LBBaP was performed with the nine-partition method (in the right anterior oblique 30° position, the ventriculogram was divided into nine partitions and the initial implant sites were located in the lower base 1/3 partitions). In X-ray image, the 3830 lead is located in the left bundle branch area, the unipolar pacing QRS wave is in the form of right bundle branch block, and the peak time from stimulation to left ventricular activation<90 ms is defined as successful operation. The clinical characters, such as the methods of venipuncture, electrode parameters, operation duration, fluoroscopy duration, the peak time from stimulation to left ventricular, pacemaker types, surgical success rate, complications, and immediate postoperative ECG parameters were collected. The patients were followed up after the operation, and the electrode parameters and postoperative complications were recorded. Results: This study is a retrospective study. There were 62 (52.5%) male patients in this cohort, the average age was (65.9±13.4) years old,and there were 49(41.5%) sick sinus syndrome, 6(5.1%) abnormal sinus node and atrioventricular node simultaneously, 63(53.4%) atrioventricular block, 26(22.0%) atrial fibrillation, 20(16.9%) cardiomyopathy; the baseline duration of QRS was (109.21±39.03) ms. Successful LBBaP was achieved in 109 patients with"nine-partition method"and the success rate was 92.4%; 104 patients (95.5%) were axillary vein puncture, 5 (4.6%) were subclavian vein puncture; the operation duration was (80.3±23.0) min, the fluoroscopy duration was (12.29±5.13) min; the QRS duration after LBBaP was (116.36±18.11) ms. The threshold of the left bundle branch (LBB) lead was (0.92±0.63) V, the R wave amplitude was (10.60±5.04) mV and the impedance was (798.71±194.90) Ω. In 1 V pacing, the peak time from stimulation to left ventricular activation was (67.91±12.15) ms, and in 5 V pacing was (67.52±12.45) ms; 1 case (0.9%) with a single-chamber pacemaker implanted, 106 cases (97.3%) with dual-chamber pacemaker and 2 cases (1.8%) with three-chamber pacemakers. There were no hematomas, pneumothorax, hemothorax, electrode dislocation, infection, and capsular hemorrhage and other serious surgery-related complications during the operation. A total of 97 patients (89.0%) were followed up for (6.21±2.90) months. The electrode parameters of all patients were stable and no complications observed. Conclusions: The LBBaP with nine-partition method is a simple, safe and effective physiological pacing approach. However, its long-term effect still needs to be further verified.

Recent approaches to His-Purkinje system pacing / 中华医学杂志(英文版)

OBJECTIVE@#Physiologic cardiac pacing is a novel technique which has been largely popularized in recent decades. His bundle pacing (HBP) has been long considered the most physiologic pacing method; however, with the widespread implementation of this method, its disadvantages have become apparent. In this context, left bundle branch pacing (LBBP)-directly engaged in the His-Purkinje system-has been foreseen as the best pacing method to mimic physiologic activation patterns. This review aimed to summarize recent approaches to physiologic cardiac pacing.@*DATA SOURCES@#This review included fully peer reviewed publications up to July 2018, found in the PubMed database using the keywords "His bundle branch pacing," "right ventricular pacing," and "physiologic pacing."@*STUDY SELECTION@#All selected articles were in English, with no restriction on study design.@*RESULTS@#The HBP has been studied worldwide, and is currently considered the most physiologic pacing method. However, it has disadvantages, such as high pacing threshold, unsatisfactory sensing and long procedure times, among others. Although LBBP is theoretically superior to HBP, the clinical relevance of this difference remains under debate, as few large randomized clinical trials with LBBP have been published.@*CONCLUSIONS@#Although HBP indeed appears to be the most physiologic pacing method, it has certain shortcomings, such as high pacing threshold, difficult implantation due to specific anatomic features, and others. Further studies are required to clarify the clinical significance of LBBP.

Relaxin inhibit cardiac fibrosis induced by phorbol 12-myristate 13-acetate / 生物医学与环境科学（英文）

Relaxin is known to inhibit cardiac fibrosis. However, it is unclear whether relaxin could regulate the effects of Phorbol 12-myristate 13-acetate (PMA, PKC activator) on cardiac fibrosis. So the influence of relaxin on the cell proliferation and collagen expression induced by PMA in cultured cardiac fibroblasts was studied. It showed that PMA significantly increased cardiac fibroblasts proliferation, Type I pro-collagen protein expression, Type I pro-collagen mRNA expression, and rhRLX absolutely significantly decreased PMA induced effects on cardiac fibroblasts proliferation and Type I pro-collagen expressions, indicating that relaxin could inhibit cardiac fibrosis induced by PMA.

Predictive value of serum uric acid on cardiovascular disease and all-cause mortality in urban Chinese patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The association between increased serum uric acid (SUA) levels and cardiovascular risk has been debated for decades. Several large studies have provided conflicting results regarding the clinical significance of elevated SUA levels in cardiovascular disease (CVD) or cerebrovascular disease. The aim of this study was to investigate the relationship between SUA and CVD and all-cause mortality and their potential diagnostic value.</p><p><b>METHODS</b>A total of 3570 in-patients ranging in age from 56 to 95 years (mean (67.36 +/- 11.36) years) were selected from 20 hospitals in Beijing and Shanghai. A carefully designed questionnaire was used to gather baseline data of each patient. All patients were divided into two main groups according to their SUA levels: high SUA and normal SUA groups. Serum indices and other important parameters were measured.</p><p><b>RESULTS</b>Compared with normal SUA group, high SUA group had significant difference in systolic blood pressure (SBP), total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), body mass index (BMI), and age (P < 0.05 or P < 0.01). High SUA prevailed in female and patients with history of essential hypertension, while history of smoking and diabetes showed no significant difference between two groups. All-cause and CVD mortality occurred more frequently in high SUA group than in normal SUA group. In the accumulative survival analysis, high SUA group had lower survival rate than normal SUA group both in CVD and all-cause mortality. COX regression analysis indicated that the history of smoking, age and high SUA were independent risk factors for the development of CVD.</p><p><b>CONCLUSIONS</b>These preliminary observations suggest that patients with high SUA levels would face higher risk of mortality. SUA measurement may be applied as a routine predictor for clinical assessment.</p>

Clinical research of heart rate turbulence on predictive value in patients with acute myocardial infarction / 中华心血管病杂志

<p><b>OBJECTIVE</b>To assess the predictive value of heart rate turbulence (HRT) in patients with acute myocardial infarction.</p><p><b>METHODS</b>One hundred and twenty-five patients with acute myocardial infarction were enrolled in this study. During the period from 6 to 21 days after onset of acute myocardial infarction, they were undergone 24-hour Holter recordings to collect the mean RR interval and heart rate variability (HRV) SDNN. The Holter files were processed with software of "HRT! View V0.60-1" to obtain the value of Turbulence Onset (TO) and Turbulence Slope (TS) and the value of "heart rate variability (HRV) SDNN". LVEF and EDD were measured by Ultrasonic Cardiography. Endpoint of follow-up was cardiac death. According to the results, patients were divided into two groups (the "survivors" and the "nonsurvivors"). The predictive value for high-risk patients with acute myocardial infarction was assessed by variables between the two groups.</p><p><b>RESULTS</b>In the period of follow-up (mean 225.4 +/- 99.8 days), 14 patients died and 111 patients survived. In the univariate Cox regression analysis, "TS" was a strong univariate predictor of mortality (hazard ratio 11.46, P < 0.01); "TO" was a relatively weak predictor and the hazard ratio was 2.76 (P > 0.05). Combination of abnormal TO and abnormal TS was the strongest mortality predictor (hazard ratio 26.70, P < 0.01); in the multivariate Cox regression analysis, TS < or = 2.5 ms/RR and EDD > or = 5.6 cm were the independent predictors of mortality with hazard ratios 9.49 (P < 0.01) and 3.64 (P < 0.05), respectively.</p><p><b>CONCLUSIONS</b>The absence of the heart rate turbulence after ventricular premature beats is a very potent post-infarction risk predictor which is independent of and stronger than other known risk predictors.</p>