胺碘酮联合β受体阻滞剂治疗急性心肌梗死并发快速心律失常的效果及对心功能影响

目的探讨急性心肌梗死并发快速心律失常患者应用胺碘酮联合β受体阻滞剂治疗的疗效及心功能变化。方法将我院收治的118例急性心肌梗死并发快速心律失常患者采用随机数字表法进行分组,对照组59例采用胺碘酮治疗,观察组59例在对照组的基础上加用β受体阻滞剂口服,比较两组临床疗效及心功能改善情况。结果观察组总有效率为91.53%,明显高于对照组的76.27%(P0.05);LVEF水平提高幅度,HR、LVEDD及LVESD水平降低幅度均优于对照组(P0.05)。结论胺碘酮联合β受体阻滞剂能有效改善急性心肌梗死并发快速心律失常患者的心功能情况,提高临床疗效。     

β-受体阻滞剂在心力衰竭治疗中的应用

β受体阻滞剂是治疗心力衰竭的重要用药,已经在我国治疗心力衰竭用药中得到了普及。β受体阻滞剂治疗高血压、冠心病、快速心律失常等领域有着重要的作用。但是对于如何应用这一药物、选择哪类β受体阻滞剂、用法用量等在我国医学上还没有系统化、规范化的阐述,为此,本文探究β受体阻滞剂在治疗心力衰竭中的应用,以指导我院在临床中正确使用这一药物。     

肥厚型心肌病的临床特征及治疗分析

目的:探讨肥厚型心肌病(hypertrophic cardiomyopathy,HCM)的临床特征及治疗方法.方法:回顾性分析我院2008年6月至2012年3月收治的85例经心脏超声或左室造影证实为肥厚型心肌病患者的临床特征及治疗方法和预后.结果:85例肥厚型心肌病患者的临床症状主要表现为胸闷、气短50例(58.8％);心前区疼痛21例(24.7％);心前区不适7例(8.2％);乏力2例(2.4％);心悸2例(2.4％);剑突下疼痛1例(1.2％);发现心电图异常前来就诊2例(2.4％).其中心尖肥厚型心肌病(apical hypertrophic cardiomyopathy)30例(35.3％);合并冠心病4例(血管狭窄小于70％)(4.8％)、心肌桥(myocardial bridge,MB)11例(12.9％)、冠状动脉粥样硬化症4例(4.8％)、冠状动脉粥样硬化症合并MB4例(4.8％)、冠心病合并MB3例(3.5％).67例患者服用β-受体阻滞剂(78.8％),4例患者同时服用β-受体阻滞剂及钙离子拮抗剂(4.8％),4例患者服用钙离子拮抗剂(4.8％),1例患者服用可达龙(1.2％),1例患者同时服用β-受体阻滞剂及可达龙(1.2％),8例患者因心率慢,未服用药物(9.6％).临床随访1～30(平均15.2±4.5)个月,临床症状均明显缓解.结论:HCM症状不典型,β-受体阻滞剂和钙离子拮抗剂在治疗肥厚型心肌病方面疗效肯定.     

β-肾上腺素受体调节蛋白及其功能

血管疾病成为威胁人类健康头号杀手,心血管受体在心血管疾病的发生、发展及预防和治疗中具有举足轻重的地位。β-肾上腺素受体作为G蛋白偶联受体家族的成员,是心血管药物最重要的靶点之一。β-肾上腺素受体阻滞剂被认为是继洋地黄后药物防治心脏疾病的最伟大突破,其在心血管领域的研究和应用一直是被关注的热点。2012年度诺贝尔化学奖再次授予了β-肾上腺素受体的研究。随着研究的深入,人们发现β-肾上腺素受体接受着细胞内调控蛋白的精密调控,不同调控蛋白介导着受体不同的生理信号通路和病理性信号通路。基于这些发现,近年来提出了受体功能选择性的配体药物,这也将成为未来药物的研究方向。本文综述了β-肾上腺素受体调节蛋白及相关信号通路及功能。     

室性心律失常相关神经机制的研究进展

室性心律失常是常见的心血管系统疾病,指起源于心室的心律紊乱,其发病率高,严重影响人类健康。目前认为,器质性与非器质性心脏病引发的室性心律失常与神经功能调节密切相关,特别是中枢神经的调节作用;心力衰竭及心肌梗死引起的心律失常与神经内分泌系统紊乱相关;脑损伤或应激创伤引起的室性心律失常与自主神经所控制的区域有关。室性心律失常的电风暴属于临床急性危重性症候群,可引起严重的血流动力学障碍,通常需要采取电复律或电除颤进行紧急治疗,而该症状的主要的促发因素被认为是过度兴奋的交感神经状态。随着研究和临床实践的不断深入,我们对室性心律失常的发生机制会形成更加系统的认识,这对疾病防治手段的完善具有积极的意义。     

心尖肥厚型心肌病的临床特征及治疗

目的:总结心尖肥厚型心肌病的临床特征及治疗方法.方法:回顾性分析我院2008年6月至2012年2月期间经心脏超声或左室造影证实的33例心尖肥厚型心肌病患者的临床特征及治疗情况.结果:患者的临床症状表现为以胸闷、气短为主者20例;心前区不适4例;心前区疼痛5例;乏力2例;心悸l例;发现心电图异常前来就诊l例.32例患者行左室造影诊断为心尖肥厚型心肌病.l例因肾功能不全,未行左室造影,但经心脏超声诊断为心尖肥厚型心肌病.27例患者服用β-受体阻滞剂,2例患者服用钙离子拮抗剂,4例患者因心率慢,未服用药物,临床随访1～36(平均16.7± 4.1)个月,临床症状均明显缓解.结论:β-受体阻滞剂和钙离子拮抗剂均适用于治疗心尖肥厚型心肌病.     

36例乌头碱中毒致室性心律失常的临床研究

目的:研究乌头碱中毒致室性心律失常是为了提高对室性心律失常的诊疗水平.方法:36例乌头碱中毒患者入院,立即洗胃,心电监护.根据心电图情况及时纠正心律紊乱,选用利多卡因、硫酸镁、氯化钾静滴及电除颤抢救.结果:36例患者有效30例,显效4例,无效2例.总有效率94.44%,乌头碱中毒时间与治疗早搏消失时间的疗效比较P值<0.05,有显著性差异.结论:乌头碱中毒所致室性心律失常治疗关键:及早药物及电复律,可提高其治愈率.     

钙通道阻滞剂和β-肾上腺阻滞剂在双层脂膜上诱导的跨膜电势

钙通道和β-肾上腺阻滞剂是治疗心血管疾患的两大类药物,它们能够缓解一些心血管疾病的症状,如心律不齐、心绞痛和高血压等,因而在临床上已得到广泛应用,但其作用机理却至今不清楚。通过本实验,我们发现:这些药物可在人工双层脂膜上建立跨膜电场。可能正是这个跨膜电场与膜中带电的离子通道发生电作用,改变离子通道的开闭状态,因而触发一系列的生理学效应,这可能是这些药物发挥药理学作用的一个重要方面。很多β-肾上腺阻滞剂都是局部麻醉剂,这     

抗β1肾上腺素受体自身抗体的致心律失常效应

目的:观察抗β1肾上腺素受体自身抗体(β1AA)在心律失常患者血清中的分布特征并探究该抗体是否具有致心律失常作用。方法:选择临床各型心律失常、冠心病患者和正常健康体检者,采用酶联免疫吸附法(ELISA)测定血清中β1AA的滴度;提纯抗体阳性患者血清中的IgG抗体,给予正常大鼠,动态监测心电图的变化,观察心律失常发生频率。结果:β1AA在心律失常患者血清中的阳性率为52.8%,明显高于冠心病对照组(24.0%,P<0.01)与正常对照组(5.0%,P<0.01);β1AA可引发正常大鼠发生心律失常,其中以室性心律失常多见。结论:β1AA在心律失常患者血清中的分布呈高阳性率,并可致大鼠发生心律失常。     

β-arrestin与β-肾上腺素受体

2012年度诺贝尔化学奖授予了美国科学家罗伯特.莱夫科维茨（Robert J.Lefkowitz）和布莱恩.克比尔卡（Brian K.Kobilka）,以表彰他们在G蛋白偶联受体研究中的贡献。从Robert J.Lefkowitz最初研究β-肾上腺素受体（β-adrenergic receptor,β-AR）减敏机制时发现β-arrestin1至今已有20多年,随着对β-arrestin在细胞信号转导中作用研究的逐渐深入,发现β-arrestin参与β-AR的减敏、内化和降解;近年来又发现,依赖β-arrestin的β-AR信号转导通路具有＂偏向激活＂现象,并提示这种依赖β-arrestin的＂偏向激活＂信号转导通路具有心脏保护作用。β-肾上腺素受体阻滞剂的发现和临床应用被视为20世纪药物治疗学上里程碑式的进展,是药物防治心脏疾病的最伟大突破,很多心血管药物都以β-AR为靶点。但是,由于目前受体药物均是针对受体本身的调控,这样在阻断了受体介导的病理性信号通路和功能的同时,也阻断了受体介导的正常生理性信号通路和功能,造成了严重的毒副作用。所以,研发能选择性阻滞β-AR过度激活介导的病理性信号通路和功能的同时,保留受体介导的正常生理性信号通路和功能（如β-arrestin信号通路）的药物,对治疗心血管疾病有重要意义,受体功能选择性的配体药物将成为未来药物的研究方向。该文将回顾β-arrestin的发现过程,综述其与β-AR的相互作用,期望能为心脏疾病的药物治疗提供参考。     

Electrical storm: Incidence, Prognosis and Therapy

Implantable defibrillators are lifesavers and have improved mortality rates in patients at risk of sudden death, both in primary and secondary prevention. However, they are unable to modify the myocardial substrate, which remains susceptible to life-threatening ventricular arrhythmias. Electrical storm is a clinical entity characterized the recurrence of hemodynamically unstable ventricular tachycardia and/or ventricular fibrillation, twice or more in 24 hours, requiring electrical cardioversion or defibrillation. With the arrival of the implantable cardioverter-defibrillator, this definition was broadened, and electrical storm is now defined as the occurrence of three or more distinct episodes of ventricular tachycardia or ventricular fibrillation in 24 hours, requiring the intervention of the defibrillator (anti-tachycardia pacing or shock). Clinical presentation can be very dramatic, with multiple defibrillator shocks and hemodynamic instability. Managing its acute presentation is a challenge, and mortality is high both in the acute phase and in the long term. In large clinical trials involving patients implanted with a defibrillator both for primary and secondary prevention, electrical storm appears to be a harbinger of cardiac death, with notably high mortality soon after the event. In most cases, the storm can be interrupted by medical therapy, though transcatheter radiofrequency ablation of ventricular arrhythmias may be an effective treatment for refractory cases.This narrative literature review outlines the main clinical characteristics of electrical storm and emphasises critical points in approaching and managing this peculiar clinical entity. Finally focus is given to studies that consider transcatheter ablation therapy in cases refractory to medical treatment.     

Thyroid Storm—A Review of Cases at University of California,San Francisco

Retrospective study of the diagnosis and management of the 8 cases of thyroid storm in a series of 400 hyperthyroid patients led to conclusion that thyroid storm is a clinical diagnosis based on a life-endangering illness in a hyperthyroid patient whose hyperthyroidism has been severely exacerbated by a serious precipitating illness, and that storm is manifest by the symptoms of hyperpyrexia, tachycardia and striking alterations in consciousness. No laboratory tests were diagnostic of storm, and the underlying precipitating cause of thyroid storm was the major determinant of survival. Vigorous therapy must include blocking synthesis of thyroid hormones with antithyroid drugs, blocking release of preformed hormone with iodine, meticulous attention to hydration and supportive therapy, as well as correction of precipitating cause of storm. The blocking of the sympathetic nervous system with reserpine or guanethidine or with alpha and beta blocking drugs may be exceedingly hazardous and requires skillful management and constant monitoring in a critically ill patient.     

Premature Ventricular Contractions and Non-sustained Ventricular Tachycardia: Association with Sudden Cardiac Death,Risk Stratification,and Management Strategies

Premature ventricular contractions (PVCs) and non-sustained ventricular tachycardia (NSVT) are frequently encountered and a marker of electrocardiomyopathy. In some instances, they increase the risk for sustained ventricular tachycardia, ventricular fibrillation, and sudden cardiac death. While often associated with a primary cardiomyopathy, they have also been known to cause tachycardia-induced cardiomyopathy in patients without preceding structural heart disease. Medical therapy including beta-blockers and class III anti-arrhythmic agents can be effective while implantable cardiac defibrillators (ICD) are indicated in certain patients. Radiofrequency ablation (RFA) is the preferred, definitive treatment in those patients that improve with anti-arrhythmic therapy, have tachycardia-induced cardiomyopathy, or have certain subtypes of PVCs/NSVT. We present a review of PVCs and NSVT coupled with case presentations on RFA of fascicular ventricular tachycardia, left-ventricular outflow tract ventricular tachycardia, and Purkinje arrhythmia leading to polymorphic ventricular tachycardia.     

The Chemotherapy of Cardiac Arrest

Direct-air ventilation, external cardiac compression, and external defibrillation are established techniques for patients who unexpectedly develop cardiac arrest. The proper use of drugs can increase the incidence of successful resuscitation. Intracardiac adrenaline (epinephrine) acts as a powerful stimulant during cardiac standstill and, in addition, converts fine ventricular fibrillation to a coarser type, more responsive to electrical defibrillation. Routine use of intravenous sodium bicarbonate is recommended to combat the severe metabolic acidosis accompanying cardiac arrest. Lidocaine is particularly useful when ventricular fibrillation or ventricular tachycardia tends to recur. Analeptics are contraindicated, since they invariably increase oxygen requirements of already hypoxic cerebral tissues. The following acrostic is a useful mnemonic for recalling the details of the management of cardiac arrest in their proper order: A (Airway), B (Breathing), C (Circulation), D (Diagnosis of underlying cause), E (Epinephrine), F (Fibrillation), G (Glucose intravenously), pH (Sodium bicarbonate), I (Intensive care).     

Magnesium Therapy for Intractable Ventricular Tachyarrhythmias in Normomagnesemic Patients

Intractable ventricular tachyarrhythmia associated with hypomagnesemia responds well to magnesium given intravenously. Two patients with recurrent ventricular tachycardia and ventricular fibrillation associated with normal serum magnesium levels and resistant to treatment with potassium chloride, lidocaine and bretylium tosylate responded dramatically to the administration of magnesium sulfate. A third patient in whom the serum magnesium level was unknown also showed dramatic response to magnesium therapy.Magnesium depletion probably interferes with sodium-potassium adenosine triphosphatase enzyme activity and causes ionic imbalance and electrical instability of purkinje''s fibers. Without obvious magnesium depletion this element in high concentration may still prolong transient inward current, prolong the effective refractory period, increase the membrane potential and control ventricular tachyarrhythmia.When ventricular fibrillation or malignant ventricular tachycardia cannot be controlled with lidocaine and other conventional drugs, we recommend infusing magnesium sulfate, 2 to 3 grams in one minute, followed by 10 grams over five hours.     

Acute transient non-physiological over-sensing in the ventricle with a DF4 lead

The DF-4 is a new defibrillator lead technology. We present two cases of non-physiological transient ventricular over-sensing in patients who underwent implantation of an ICD for secondary prevention. Case 1 had ventricular over-sensing during pacing threshold evaluation post defibrillation testing while Case 2 had the lead integrity alert triggered immediately post discharge with transient over-sensing. No lead-connector issues were found. Case 1 was likely due to improper venting of the header and trapped air. Case 2 was hypothesized to be due to intermittent header pin non-contact secondary to blood in the header. These cases reveal that DF-4 leads are subject to both reported and potentially novel causes of transient acute ventricular over-sensing.     

Successful catheter ablation of persistent electrical storm late post myocardial infarction by targeting purkinje arborization triggers

Drug refractory ventricular tachycardia (VT) occurring as a storm after acute myocardial infarction has grave prognosis. We report a case of a middle-aged lady who presented with drug refractory VT that lead to persistent electrical storm two weeks after an anterior wall myocardial infarction. She underwent a successful catheter ablation of VT followed a few days later by implantation of an AICD. Catheter ablation of the VT could control the persistent electrical storm and the patient was free from a recurrence of VT at three month follow up.     

Ventricular Tachycardia Storm - An Atypical Presentation of Sarcoidosis Exacerbation

Management of ventricular tachycardia (VT) storm in a patient with an implantable cardioverter-defibrillator (ICD) is a challenging medical emergency. We describe a patient with cardiac sarcoidosis (CS) and an ICD who is admitted with VT storm. Management of VT was difficult due to resistance to multiple antiarrhythmic drugs. He responded to immunosuppressive therapy supporting active CS as the cause of his VT. This case suggests that CS may underlie some cases of refractory VT and that immunosuppressive therapy may be effective in controlling this arrhythmia.     

Mechanically induced electrical storm as a complication of cardiac resynchronization therapy: A case report

BackgroundCardiac resynchronization therapy (CRT) has been shown to improve both the functional status and mortality of heart failure patients with left bundle branch block. Multiple recent studies suggest several mechanisms for proarrhythmia associated with CRT device.Case summaryA 51-year-old male with symptomatic non-ischemic cardiomyopathy and no previous history of ventricular arrhythmias underwent placement of a biventricular cardioverter-defibrillator. The patient developed sustained monomorphic ventricular tachycardia (VT) soon after implantation. The VT recurred despite reprogramming to right ventricular only pacing. The electrical storm resolved only after a subsequent discharge from the defibrillator caused inadvertent dislodgement of the coronary sinus lead. No recurrent VT occurred throughout 10-years follow up after urgent coronary sinus lead revision.DiscussionWe describe the first reported case of mechanically induced electrical storm due to the physical presence of the CS lead in a patient with a new CRT-D device. It is important to recognize mechanical proarrhythmia as a potential mechanism of electrical storm, as it may be intractable to device reprogramming. Urgent coronary sinus lead revision should be considered. Further studies on this mechanism of proarrhythmia are needed.     

急性冠脉综合征患者急诊PCI术后心力衰竭的危险因素分析及护理干预

目的:探讨急性冠脉综合征(ACS)患者行急诊直接经皮冠状动脉介入治疗(PCI)后住院期间发生心力衰竭(HF)的危险因素分析及护理干预策略。方法:选取278例在我院接受急诊PCI手术患者为研究对象,按照术后住院期间是否出现心力衰竭分为两组:心力衰竭组(n=54例)和非心力衰竭组(n=224例),比较两组患者一般临床资料、实验室检查指标及相关治疗情况的差异,用Logistic回归分析探讨影响术后心力衰竭发生的危险因素,并制定相关护理策略。结果:278例老年患者中有54例PCI术后出现心力衰竭(发生率19.4%);两组患者在年龄、高血压、糖尿病、入院收缩压(SBP)、发病至PCI时间、入院血糖、入院NT-pro BNP、肌酸激酶同工酶(CK-MB)峰值、肌酐蛋白I(c Tn I)峰值、左室射血分数(LVEF)、左室舒张末内径(LVEDd)、术后TIMI血流、使用他汀类药物、β-受体阻滞剂方面存在统计学差异(P0.05);发病至PCI时间、高血压、入院时血糖、NT-pro BNP、c Tn I峰值是术后心力衰竭发生的独立危险因素(P0.05);而术后TIMI血流、使用β-受体阻滞剂治疗是保护性因素。结论:ACS患者行急诊PCI治疗后HF的发生受到多种因素的影响,应当积极制定相关护理干预策略以降低术后HF的发生率。