高血压患者左室构型和房性心律失常的关系

目的了解高血压患者左室构型和房性心律失常关系。方法应用超声心动图及动态心电图，测定左室结构及房性心律失常发生率。结果Ｋｌｅｉｇｅｒ３～６发生和构型有联系（Ｐ＜０．００１）。结论左室构型影响房性心律失常。     

三七中人参三醇甙对大鼠离体心脏缺血再灌注损伤及心律失常的保护作用

三七中人参三醇甙(PTS)5,50μg·ml~(-1)灌流对离体大鼠Langendorff心脏缺血再灌注所致心律失常具有明显的保护作用,可降低室颤发生率,并可保护心肌组织中超氧化物歧化酶的降低,PTS 50μg·ml~(-1)还可抑制心肌丙二醛的产生,对缺血再灌注所致心肌乳酸脱氩酶和磷酸肌酸激酶的漏出亦有明显的抑制作用。     

Pharmacology of KB‐R7943: A Na+–Ca2+ exchange inhibitor

The Na⁺–Ca²⁺ exchange (NCX) system plays a pivotal role in regulating intracellular Ca²⁺ concentration in cardiomyocytes, neuronal cells, kidney and a variety of other cells. It performs a particularly important function in regulating cardiac contractility and electrical activity. One of the leading NCX inhibitors is KB‐R9743 (KBR) that appears to exhibit selectivity for Ca²⁺‐influx‐mode NCX activity (reverse mode of NCX). In this article we reviewed pharmacology of KBR and provide a brief summary of studies with other NCX inhibitors, such as SEA0400 (SEA) and SN‐6 (SN). Potential clinical usefulness of KBR and other NCX inhibitors is still controversial but the reviewed findings may be helpful in designing more selective and clinically useful NCX inhibitors for the treatment of cardiac, neuronal and kidney diseases.     

中西医结合治疗肺心病心律失常40例疗效观察

为提高肺心病心律失常的临床疗效,采用中药清肺化痰活血剂配合抗菌素及氧疗法对40例肺心病并发心律失常患者进行了治疗观察,同时与单纯使用抗菌素及氧疗法治疗的40例患者进行对照。临床以心电图改善情况为观察指标,结果两组有效率分别为87.5％和67.5％。Ridit分析结果表明,治疗组疗效明显优于对照组,经显著性检验,两组差异显著(P<0.05)。     

Early developmental 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure decreases chick embryo heart chronotropic response to isoproterenol but not to agents affecting signals downstream of the beta-adrenergic receptor.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) causes cardiovascular toxicity in laboratory animals, including alteration in several processes in which beta-adrenergic receptor (beta-AR) signaling plays important roles. Thus, our laboratory investigated the effects of TCDD on beta-AR expression and signal transduction. Fertile chicken eggs were injected with vehicle (corn oil), 0.24 or 0.3 pmol TCDD/g egg on incubation day 0 (D0) or D5. On D10, heart function was assessed by ECG in ovo. Exposure to TCDD increased the incidence of arrhythmias and decreased the positive chronotropic responsiveness of the heart to isoproterenol. The reduced beta-AR responsiveness was, in part, independent of any overt morphological changes in the heart as chick embryos exposed to TCDD on D5 displayed an intermediate responsiveness to beta-AR agonist in the absence of the dilated cardiomyopathy observed in chick embryos exposed to TCDD on D0. TCDD did not decrease the chronotropic response of the heart to agents that stimulate signals downstream of the beta-AR. In fact, TCDD-exposed embryos were more sensitive than controls to forskolin, increasing heart rates (HR) 21.8 +/- 3.5 beats per min (bpm) above baseline versus control values at 6.3 +/- 2.7 bpm above baseline. TCDD exposure also augmented the negative chronotropic response of the heart to verapamil, decreasing HR -23.2 +/- 7.4 bpm relative to baseline versus control embryos at -12.7 +/- 5.9 bpm below baseline. Finally, the mean cardiac beta1-AR mRNA expression in D10 embryos was not significantly altered by exposure to TCDD on D0. These findings establish that a functional end point of the developing chick heart is sensitive to TCDD exposure and that the TCDD-induced reduction in beta-AR responsiveness may result from alterations in signal transduction upstream of adenylyl cyclase.     

207例预激综合征的心律失常

对207例预激综合征行电生理检查.检出心律失常171例.占82.6%。房室折返性心动过速占所有心律失常的80.4%,心房颤动13.1%,其他6.5%.房室折返性心动过速占我院同期室上速的56.5%.远较房室结折返性心动过速(24.4%)多见。隐性旁路在室上速中占29%,居首位。上述情况反映我国人室上速的构成比可能与西方国家不同。     

Upper Gastrointestinal Irritation and Arrhythmia

Abstract: The influence of endoscopic examination on the occurrence of arrhythmia was investigated electrocardiographically in 30 patients with cardiovascular disease who underwent transesophageal echocardiography (TEE) (group A) and 38 patients with digestive tract disease who underwent upper gastrointestinal endoscopy (UGIE) (group B). The mode and frequency of arrhythmia during the examination were compared between the two groups. (1) Arrhythmia was more frequently observed in group A (22 of 30, 73.3%) than in group B (9 of 38, 23.7%) patients (p<0.001). The common arrhythmias in both groups were supraventricular premature beat and ventricular premature beat. Serious arrhythmias, such as 2nd degree atrioventricular block and ventricular fibrillation were detected only in group A patients. (2) The region of the esophagus where the tip of the probe or scope was located was classified into three segments: upper (0–15 cm), middle (15–35 cm) and lower (35 cm<). Arrhythmias tended to be frequent when the tip of the probe or scope was located in the middle segment of the esophagus. These data indicate that arrhythmias observed during TEE or UGIE are related to the underlying heart disease. Furthermore, the middle segment of the esophagus appears to be particularly susceptible to the provocation of arrhythmia.     

高频消融心室肌和心律失常的实验研究

应用2.59MHz的高频消融心室肌和兔实验性心律失常的兴奋灶。结果表明,高频可引起心肌局灶性凝固性坏死;高频消融乌头碱注射部位,可使实验性心律失常恢复正常的时间明显缩短。高频消融未见有并发症。     

Heart rate and late mortality in cardiac transplant recipients

There are currently 104 patients at this centre who have survivedat least 3 months after orthotopic cardiac transplantation.Seven of these long-term survivors have subsequently died andin three cases death was sudden and unexpected. All three ofthese patients had been noted to have inappropriately high restingheart rates (>130 b.min^–1) The rhythm was sinus tachycardia,supraventricular tachycardia or both intermittently. The heart rates of all 104 long-term survivors were recordedfrom ECGs taken at routine follow-up visits every 3 months forone year and annually thereafter. The overall mean heart ratewas 100±13.2 b.min^–1. Four patients, including the three identified above, had meanheart rates greater than the 95th centile. The mortality ratein this group is 75%. Four deaths have occurred in the remaining100 patients (P <0.001). In our series, an inappropriately high resting heart rate dueto sinus tachycardia or supraventricular tachycardia in long-termsurvivors of cardiac transplantation, is an adverse prognosticsign.     

Effects of halothane on arrhythmias induced by myocardial ischaemia

The effect of halothane on arrhythmias induced by ischaemia was investigated in rats, isolated perfused rat hearts, and pigs. Responses to the occlusion of the left anterior descending coronary artery were determined in groups (n = 9) of chronically prepared rats treated with no halothane, 0.5, or 1.0 per cent halothane immediately after occlusion; in isolated rat hearts (n = 10) treated with no halothane, 0.5, 1.0, 2.0, or 4.0 per cent halothane for 15 min before and after occlusion; and 20–25 kg pigs (n = 11) anaesthetised with halothane or pentobarbital. The ECG, arrhythmias, blood pressure (BP), heart rate (HR) and extent of infarction were determined in each model. In pigs, left ventricular pressure, dp/dt_max and cardiac output were also measured. In chronically prepared rats, halothane anaesthesia started after occlusion was antiarrhythmic and decreased the incidence of ventricular fibrillation and resulting mortality. In isolated rat hearts, 0.5 or 1.0 per cent halothane had little effect on occlusion-induced arrhythmias. The highest concentration of halothane increased the incidence of ventricular fibrillation both before and after occlusion. Halothane decreased developed ventricular pressure in a dose-dependent manner. In acutely prepared pigs, halothane pre-treatment had no appreciable effect upon occlusion-induced arrhythmias when compared with pentobarbital anaesthesia. Thus, halothane is antiarrhythmic when treatment is initiated after occlusion in the rat but this action is not seen in isolated hearts or intact pigs. The antiarrhythmic action of halothane is, therefore, species and model dependent.