多普勒,2—DE,左房收缩时间间期评价陈旧性心肌梗塞病人的左房功能

本文应用脉冲多普勒方法测量左房收缩时间间期,结合M、二维超声心动图定量评价24例陈旧性心肌梗塞病人的左房功能。结果显示:陈旧性心梗组左房收缩时间间期各指标与对照组相比有明显差异。左房每搏量、左房射血分数、左房每搏量与左室每搏量之比比对照组明显增加。这些结果提示:心肌梗塞后,左房收缩功能增强,对维持左室充盈量起重要作用,其代偿机理符合Frank·Starling定律。     

Full Ventricular Capture Indicated by the QT Interval Function

The atrioventricular (AV) interval is critical in dual chamber (DDD) pacing in patients with hypertrophic obstructive cardiomyopathy (HOCM) to obtain full ventricular capture (FVC) with maximal reduction of the left ventricular (LV) outflow gradient and optimal LV diastolic filling. We studied the relationship of FVC, fusion, spontaneous AV conduction, and the QT interval. Methods: 11 patients with various cardiac diseases and stable AV conduction received a QT sensing Diamond (tm) Vitatron, DDD pacemaker. Software was downloaded into the pacemaker. In the DDD pacing mode, with the QT interval measured from the ventricular pacing stimulus to the end of the T wave, the AV interval was shortened from 400 ms, in 20-ms steps, to 90 ms. At 90 ms the stimulation rate was increased by 30 beats/mm and the AV interval was increased stepwise. FVC and fusion was examined on the surface ECG, Results: At 400 ms interval, spontaneous AV conduction inhibited the pacemaker. Shortening the AV interval resulted in pacing with a short QT interval. Further reduction of the AV interval resulted in a longer QT interval up to a point where the QT interval became stable. This point, the bending point in the plot of measured QT interval versus shortened AV intervals, coincided with the point of FVC. The relation of the QT-AV interval plot and the point of fusion was comparable when lengthening the AV interval at a 30 beats/mm faster stimulation rate. Conclusion: The bending point in the QT interval versus AV interval plots showed a good correlation with the FVC and fusion points observed on ECG. The results suggest that automatic discrimination between fusion and full capture using QT interval measurements may be feasible.     

Unusual Features of Right and Left Idiopathic Ventricular Tachycardia Aholished hy Radiofrequency Catheter Ablation

Two unusual cases are presented with idiopathic right and left ventricular tachycardia(IVT) with intriguing clinical and electrophysiological characteristics. The first patient with a sustained IVT of right ventricular outflow tract origin, and an electrophysiological mechanism suggesting reentry, had been resuscitated from cardiac arrest. The second patient had an IVT with a left bundle branch block morphology, which originated from the basal-septal region of the left ventricle(left ventricular outflow tract tachycardia). Both patients were cured with radiofrequency catheter ablation, guided by endocardial activation sequence and pace mapping.     

Propafenone-Induced Torsade de Pointes: Cross-Reactivity with Quinidine

A 77-year-oid/emale with new onset atrial fibrillation occurring in the absence of structural heart disease developed torsade de pointes during therapy with quinidine bisulfate 500 mg orally every 8 hours. Ten days after quinidine therapy had been discontinued she developed torsade de pointes while receiving propafenone 300 mg orally every 8 hours. This case demonstrates that propafenone may be associated with torsade de pointes and suggests a cross-reactivity between this effect and prior occurrence of torsade de pointes on Class IA antiarrhythmic drug therapy.     

非透析慢性肾脏病患者sST2、NT-proBNP、hs-cTnT与左心室构型的相关性

目的 左室重构和肥厚在慢性肾脏病（Chronic Kidney Disease, CKD）患者中十分常见,并与其不良预后相关。可溶性生长刺激表达基因2蛋白（soluble growth Stimulation expressed gene 2, sST2）是一种与心脏重构相关的新型循环标志物。本研究探讨了CKD患者sST2和传统心脏标志物与左心构型的相关性。 方法 纳入2019年8月至2020年12月在上海复旦大学附属中山医院肾病科诊治的CKD患者。收集患者临床资料,检测心脏标志物sST2、N端脑钠肽前体（N-terminal pro-B-type natriuretic peptide, NT-proBNP）、高敏肌钙蛋白T（high-sensitivity cardiac troponin , hs-cTnT）。采用经胸超声心动图评估左心室结构,根据左心室质量指数（Left Ventricular Mass Index, LVMI）和相对室壁厚度（Relative Wall Thickness, RWT）定义左心室几何构型。采用受试者工作特征（Receiver operating characteristic , ROC）曲线分析各心脏标志物对左心室肥厚（Left Ventricular Hypertension, LVH）的预测效能。采用事后检验分析各左心构型间心脏标志物的组间差异。采用多元线性回归分析心脏标志物与心脏结构参数之间的相关性。 结果 共纳入CKD患者652例。LVH的检出率为33.4%,检出率随着肾功能的恶化而增加,在CKD5期患者为64.3%。与正常构型患者相比,NT-proBNP和cTNT水平在向心性或离心性肥厚组中均显著升高,而sST2水平仅在向心性肥厚组中显著升高。多元线性回归分析示NT-proBNP与左房内径、左心室舒张末期内径、左心室收缩末期内径、后壁厚度、室间隔厚度、左心室射血分数、左心质量和LVMI相关,hs-cTNT与左房内径、后壁厚度、室间隔厚度、左心质量、RWT和LVMI相关,sST2与左房内径、LVMI相关。 结论 sST2在向心性肥厚的CKD患者中明显升高,这一特征不同于传统心脏标志物。ST2/白细胞介素-33通路在CKD患者心脏重构过程中的作用机制有待进一步研究。     

Early growth response gene 1-mediated apoptosis is essential for transforming growth factor beta1-induced pulmonary fibrosis

Fibrosis and apoptosis are juxtaposed in pulmonary disorders such as asthma and the interstitial diseases, and transforming growth factor (TGF)-beta(1) has been implicated in the pathogenesis of these responses. However, the in vivo effector functions of TGF-beta(1) in the lung and its roles in the pathogenesis of these responses are not completely understood. In addition, the relationships between apoptosis and other TGF-beta(1)-induced responses have not been defined. To address these issues, we targeted bioactive TGF-beta(1) to the murine lung using a novel externally regulatable, triple transgenic system. TGF-beta(1) produced a transient wave of epithelial apoptosis that was followed by mononuclear-rich inflammation, tissue fibrosis, myofibroblast and myocyte hyperplasia, and septal rupture with honeycombing. Studies of these mice highlighted the reversibility of this fibrotic response. They also demonstrated that a null mutation of early growth response gene (Egr)-1 or caspase inhibition blocked TGF-beta(1)-induced apoptosis. Interestingly, both interventions markedly ameliorated TGF-beta(1)-induced fibrosis and alveolar remodeling. These studies illustrate the complex effects of TGF-beta(1) in vivo and define the critical role of Egr-1 in the TGF-beta(1) phenotype. They also demonstrate that Egr-1-mediated apoptosis is a prerequisite for TGF-beta(1)-induced fibrosis and remodeling.     

二维斑点追踪技术对老年舒张性心力衰竭患者左室心肌收缩运动的评估价值

目的探讨二维斑点追踪技术(2D-STI)评估老年舒张性心力衰竭患者左室心肌收缩运动的价值。方法选取48例因舒张性心力衰竭入院的老年患者,设为A组;门诊检查疑似舒张性心力衰竭的老年患者52例,设为B组;健康志愿者51例,设为C组。采用二维斑点追踪技术,测定各组患者左室径向18节段收缩期峰值心肌应变。结果 A、B组E/A、E/E'、LVDs、IVSd显著高于C组(P0.05);A组E/A、E/E'、LVDs、IVSd显著高于B组(P0.05)。A组18节段收缩期峰值心肌应变均显著低于B组、C组(P0.05)。结论二维斑点追踪技术在反映局部心肌收缩运动异常上具有更高的敏感性。     

应用心脏磁共振Tissue tracking探讨右室长轴心肌应力与年龄性别的关系

目的应用心脏磁共振Tissue tracking评估健康中国人右心室心肌长轴应力参数范围,以及分析其与年龄性别的关系。材料与方法以在中国医科大学附属第一医院接受心脏磁共振扫描的100名健康志愿者为研究对象,年龄20～70岁,平均年龄(45.4±15.3)岁,10岁一个年龄段分为5组,每组20人,应用德国SiemensVerio3.0TMR自由进动稳态序列采集右心室电影序列图像,实施组织追踪技术获取右室长轴应力及应力率,并对结果进行统计学分析。纳入标准:无先天性或者获得性心脏疾病、无高血压、糖尿病、血脂异常、肥胖以及全身性疾病,左室收缩和舒张功能正常。结果整体长轴应力峰值(global longitudinal strain,GLS)为(-24.2±4.6)%,女性与男性比较差异无统计学意义[(-24.7±5.3)%vs (-23.5±3.6)%,P>0.05];整体长轴应力峰值与年龄无相关性(P>0.05),长轴收缩期应力率(GLS S')为-1.6±0.6(1/s),女性与男性比较差异无统计学意义[-1.7±0.6(1/s) vs-1.5±0.7(1/s),P>0.05)];长轴舒张期应力率(GLS D')为1.3±0.4(1/s),女性与男性比较差异无统计学意义[1.3±0.3(1/s) vs 1.4±0.4(1/s),P>0.05];长轴收缩期应力率(GLSD')与年龄无相关性(P>0.05);长轴舒张期应力率(GLS D')与年龄亦无相关性(P>0.05)。结论应用心脏磁共振Tissue tracking可以有效且可重复性获取右心室心肌应力参数,健康中国人右心室心肌长轴应力及应力率与年龄性别不存在显著相关性,因此右心室长轴心肌应力及应力率正常参数可以为临床右心室心脏疾病早期诊断提供参考标准。     

Removal of coronary sinus intima by a guidewire during cardiac resynchronization therapy

Previously, complications associated with the placement of the left ventricular pacing lead were reported in 1.9-6% of cases. We describe a case with a stripping of venous intima from the coronary sinus by a guidewire during a left ventricular lead implantation. Judging from this case, the firm guidewire and coronary catheter should not be used within the coronary sinus.