延迟增强心肌磁共振定量分析对缺血性心肌病患者室性心律失常预测价值

目的探索延迟增强心脏磁共振成像(DE-CMR)定量分析对缺血性心肌病患者发生室性心律失常的预测价值。方法 41例缺血性心肌病伴有左心室射血分数≤35%的患者在植入心脏转复除颤器(ICD)前进行DE-CMR检查,对心肌延迟增强定量分析,并对ICD定期程控记录室性心律失常发生情况。结果在平均(441±209)d随访中,12例(29%)患者ICD)记录到自发或治疗终止的持续性室性心动过速或心室颤动。发生室性心律失常患者的增强心肌质量及其占左心室心肌质量百分比均显著高于无室性心律失常组[(60.1±24.4)g比(40.9±20.1)g,P=0.01)及(51.8%±20.0%)比(37.8%±15.2%),P=0.02]。受试者工作特征曲线(ROC)分析显示增强心肌质量或其百分比对室性心律失常预测价值高于射血分数。在多因素分析中,增强心肌质量(HR 1.54/10 g;95%CI1.06～2.45,P=0.02)或其百分比(HR 1.65/10%;95%CI 1.05～2.58;P=0.03)是惟一的发生室性心律失常预测因子。结论 DE-CMR定量分析是预测缺血性心肌病患者发生室性心律失常的独立危险因子。     

植入埋藏式心脏转复除颤器患者室性心律失常发生的多因素分析

目的探讨植入埋藏式心脏转复除颤器(ICD)患者术后发生室性心动过速/心室颤动(简称室速/室颤)的危险因素。方法回顾分析植入ICD/心脏再同步化治疗除颤(CRTD)的患者51例,随访(39.4±22.3)个月,19例ICD/CRTD记录到持续性室速和或快室速、室颤,为室性心律失常组;32例ICD/CRTD未记录到持续性室速和或快室速、室颤事件,为非室性心律失常组。分析ICD/CRTD植入患者发生室性心律失常的临床因素以及两组患者临床事件的发生情况,并作logistic回归分析。结果对51例ICD/CRTD植入患者月随访中,发现有19例(37.3%)ICD/CRTD记录到室速/快室速/室颤,而且ICD/CRTD给予恰当治疗(ATP或电击),其中3例经历了室速电风暴。对ICD/CRTD植入患者术后室性心律失常和临床事件发生作多因素分析发现,室性心律失常的发生与术后12个月的左室射血分数(LVEF)值显著相关(r=0.149,P=0.047),ICD/CRTD术后住院/死亡的发生与缺血性心肌病(r=17.643,P=0.045)、可达龙(r=14.672,P=0.013)、室性心律失常(r=21.561,P=0.046)显著相关。结论术后12个月LVEF值的显著提高可减少室性心律失常的发生。缺血性心肌病及术后室性心律失常的发生会增加ICD/CRTD植入患者术后住院/死亡的发生,而可达龙可有效降低住院/死亡率。     

ICD在恶性室性心律失常治疗中的应用

目的观察埋藏式心脏复律除颤器(ICD)在治疗恶性室性心律失常中的作用。方法对2005年1月至2009年11月在我院植入ICD的96例患者的临床资料及植入ICD后的长期随访结果进行回顾性分析,其中男80例,女16例,年龄14~79岁(53±12.2岁)。结果①植入ICD进行一级预防的患者32例(33.33%),二级预防64例(66.67%);②病因分析显示致心律失常性右室心肌病11例(11.46%),肥厚型心肌病8例(8.33%),缺血性心肌病29例(30.21%),扩张型心肌病13例(13.54%),长QT综合征1例(1.04%),Brugada综合征10例(10.42%),多形性室速19例(19.79%),特发性室颤4例(4.17%),心肌致密化不全1例(1.04%);③临床表现为持续性室速或室颤64例(66.67%),其中合并有房速16例(16.67%);④起搏模式为:单腔ICD54例(56.25%),双腔ICD42例(43.75%);⑤术中测试ICD的起搏参数并诱发心室颤动,采用20J一次电击复律成功;⑥随访结果显示植入ICD后共发生室性心律失常事件426阵次,共启动抗心动过速起搏(ATP)治疗378阵次,成功304次(成功率80.42%);高能量放电90次;有3次为窦性心动过速或房颤伴快速心室率所致的不恰当治疗。结论 ICD能有效治疗恶性室性心律失常,预防心脏性猝死;ATP是ICD治疗的有效方法;术后定期随访,及时优化ICD参数,合理选用辅助治疗,可减少不恰当治疗及提高ICD治疗的成功率。     

微伏极T波电交替筛选慢性心力衰竭患者预防性植入心脏复律除颤器的临床研究

目的:探讨微伏极T波电交替(MTWA)是否有助于选择预防性植入心脏复律除颤器(ICD)的慢性心力衰竭(心衰)患者,尤其是否有助于排除从ICD治疗中获益较少的低危患者。方法:入选左室射血分数(LVEF)≤35%并且无持续性室性心律失常的39例缺血性或非缺血性心肌病患者,所有患者用动态心电图时域分析法检测MTWA最大值。V3导联电压47μV为阳性,电压≤47μV为阴性。MTWA测定后所有心衰患者植入ICD进行一级预防。术后1、3、6个月各随访1次,以后每6个月随访1次。主要终点为全因死亡或非致死性持续性室性心律失常。结果:有19例患者(48.7%)MTWA检查结果为阳性。在(20±4)个月的随访期内,MTWA阳性组发生13例终点事件(1例死亡和12例非致死性持续性室性心律失常),MTWA阴性组发生1例终点事件(1例非致死性持续性室性心律失常)。MTWA阳性预测价值为68.4%,阴性预测价值为95%。结论:对于LVEF≤35%且无持续性室性心律失常的缺血性或非缺血性心肌病患者,MTWA不仅有助于选择预防性植入心脏ICD的高危患者,而且有助于确定从预防性ICD植入中获益较少的低危患者。     

埋藏式心脏复律除颤器对缺血性心肌病患者存活率的影响

国外多个大规模临床试验表明埋藏式心脏复律除颤器(ICD)能够有效终止缺血性心肌病伴左心功能不全患者的恶性室性心律失常,显著降低心脏性猝死(SCD)的发生率。到目前为止我科已对15例缺血性心肌病伴左心功能不全和恶性室性心律失常的患者植入了ICD,我们比较了传统的药物治疗和ICD对此类患者生存率的影响。资料与方法1·临床资料:回顾性分析2002年1月至2006年3月明确诊断为缺血性心肌病伴左心功能不全的患者152例。患者的NYHA分级为Ⅱ或Ⅲ级,心电图或动态心电图有恶性室性心律失常(持续性室性心动过速或心室颤动)证据,心脏超声检查示左…     

埋藏式心律转复除颤器在43例遗传性心律失常患者中应用的疗效评价

目的:对因遗传性心律失常植入埋藏式心律转复除颤器(ICD)患者术后情况及ICD治疗效果进行总结。方法:对我院从2004-01至2011-06出院诊断为长QT综合征、Brugada综合征、致心律失常性右心室心肌病及肥厚型心肌病并且植入了ICD的43例患者进行随访,了解患者术后室性心律失常的发作情况以及ICD的治疗效果。结果:43例患者共随访8～84(37.0±20.6)个月,无患者死亡。经ICD共记录到369次室性心动过速(室速)事件及13次心室颤动(室颤)事件,均被ICD成功终止,ICD共启动治疗程序498次。16例(37.2%)患者在随访期内发生室速/室颤事件,被ICD正确识别并接受了恰当的治疗。无患者因室速/室颤事件发生晕厥。对于室速事件,抗心动过速起搏终止的总成功率为53.4%(197/369),首次成功率为20.8%(77/369)。6例(13.9%)患者发生了不恰当识别,1例(2.3%)患者发生了未识别事件。结论:ICD是治疗遗传性心律失常患者室性恶性心律失常的有效措施,合理设置治疗方案及参数可使ICD更充分地发挥预防猝死的作用。     

植入型心律转复除颤器治疗恶性室性心律失常的疗效评价

目的评价单中心40例植入型心律转复除颤器(ICD)治疗恶性室性心律失常的疗效及安全性。方法40例恶性室性心律失常包括室性心动过速(室速)或心室颤动(室颤)患者接受ICD治疗,男性35例,女性5例,平均年龄(49±15)岁,成功随访35例,应用体外程控仪获得ICD储存资料并结合临床随访资料进行分析。结果40例患者均成功植入ICD;35例患者平均随访25个月,其中26例患者共记录室速和室颤事件763阵,ICD成功除颤224阵(成功率99．1％),抗心动过速起搏1次成功终止室速375阵(成功率71．8％),低能量同步转复22阵(成功率100％);2例患者因窦性心动过速和心房颤动伴快速心室反应发生误放电4次。术后大多数患者联合应用抗心律失常药物。至随访期末,死亡4例,3例死于顽固性心力衰竭,1例死于肺栓塞。结论ICD联合应用抗心律失常药物能有效治疗恶性室性心律失常,预防心脏性猝死。     

心脏再同步治疗慢性心力衰竭的植入术并发症及术后病死率分析

目的分析心脏再同步治疗(CRT)术中、术后并发症及病死率。方法心力衰竭患者45例,男性37例,女性8例,年龄平均(61.08±11.16)岁,其中扩张性心肌病(DCM)30例,高血压性心脏病(HHD)5例,缺血性心肌病(CHD)10例,心功能Ⅲ级(NYHA分级)21例、Ⅳ级24例。均成功植入双心室起搏系统,平均随访(21.88±15.81)个月。结果(1)并发症左心室电极导线脱位2例(4.4%),膈肌跳动3例(6.7%),心脏静脉穿孔1例(2.2%),术中急性左心衰竭1例(2.2%);(2)病死率45例患者共死亡11例(24.5%),其中3例为非心源性死亡(占总病死率的27%),8例为心源性死亡(占总病死率的73%)。在心源性死亡中,5例心脏性猝死(占心源性死亡的62.5%)。2例为急性心肌梗死后死亡(占心源性死亡的25.0%),死亡前未发生恶性室性心律失常。1例因心力衰竭恶化死亡(占心源性死亡的12.5%)。结论CRT植入术有一定的风险,主要是左心室电极导线的植入过程,需细心观察,仔细操作,才能把并发症降低到最低限度。CRT治疗能降低心力衰竭导致的病死率,但并不降低严重室性心律失常所致的猝死,为预防猝死应选用双心室起搏+植入型心律转复除颤器(CRT-D)治疗效果更佳。     

心力衰竭患者植入心脏再同步化治疗除颤器后恰当放电情况以及序贯管理

目的:了解不同病因心力衰竭患者接受心脏再同步化治疗除颤器(CRT-D)治疗后室性心律失常的发生情况以及CRT-D诊断和治疗情况,分析CRT-D治疗后室性心律失常发生的独立预测因素,明确CRT-D放电对死亡率的影响,探讨CRT-D恰当放电的管理措施及效果。方法:对2009-01至2015-04期间我科成功植入CRT-D的42例患者进行随访,缺血性心肌病组12例,其中埋藏式心脏复律除颤器(ICD)一级预防8例,ICD二级预防4例;非缺血性心肌病组30例,其中ICD一级预防19例,ICD二级预防11例。对恰当放电的患者采用药物调整、器械参数调整、血运重建及射频消融的序贯治疗。结果:缺血性心肌病组平均随访(38.1±24.0)个月,7例患者术后发生室性心律失常,5例患者CRT-D恰当放电。非缺血性心肌病组平均随访(27.5±17.8)个月,11例患者术后发生室性心律失常,10例患者CRT-D恰当放电。两组差异无统计学意义(P0.05);缺血性心肌病组患者的数阵抗心动过速起搏(ATP)治疗室性心律失常的成功率高于非缺血性心肌病组(69%vs 55%,P0.05)。COX模型多因素回归分析显示ICD二级预防是术后室性心律失常发生的独立影响因子(P=0.001)。随访期间,CRT-D放电患者的死亡率明显高于CRT-D无放电患者(43%vs 0%,P0.05)。经药物调整、器械参数调整、血运重建及射频消融的四步序贯治疗,缺血性心肌病组中80%的恰当放电患者未再放电。经药物调整、器械参数调整及射频消融的三步序贯治疗,非缺血性心肌病组中90%的恰当放电患者未再放电、10%的患者放电减少。结论:ICD二级预防是术后室性心律失常发生的独立影响因子;植入CRT-D的患者,如果出现放电事件,死亡风险会增加;药物调整、器械参数调整以及血运重建、射频消融的序贯治疗对减少CRT-D恰当放电相当重要。     

fQRS波对DCM伴恶性室性心律失常患者预后研究

目的探讨扩张型心肌病心力衰竭碎裂QRS波恶性室性心律失常患者的预后。方法将56例扩张型心肌病心力衰竭碎裂QRS波恶性室性心律失常患者组(观察组)接受电除颤、电复律、植入型心律转复除颤器及相关药物救治的预后与56例扩张型心肌病碎裂QRS波非恶性室性心律失常患者组(对照组)进行对比分析。结果观察组的1年内病死率18例(32.14%),对照组3例(5.35%),p0.01。观察组中5例接受植入型心律转复除颤器后1年内均存活。结论扩张型心肌病心力衰竭碎裂QRS波恶性室性心律失常患者的病死率较高,此类患者采用电除颤和电复律、植入型心律转复除颤器及相关药物治疗,可改善预后,降低病死率。     

Subanalyses of secondary prevention implantable cardioverter-defibrillator trials: antiarrhythmics versus implantable defibrillators (AVID), Canadian Implantable Defibrillator Study (CIDS), and Cardiac Arrest Study Hamburg (CASH)

PURPOSE OF REVIEW: Controlled trials for secondary prevention of sudden death--Antiarrhythmics Versus Implantable Defibrillators (AVID), Canadian Implantable Defibrillator Study (CIDS), and Cardiac Arrest Study Hamburg (CASH)--have been published and subanalyses of them provide useful clinical information on the outcome during the follow-up of this population. RECENT FINDINGS: Results from a meta-analysis showed a significant risk reduction (RR) of 25 to 27% of total mortality (P < 0.001) and 50 to 52% of arrhythmic death (P < 0.001). Compared with amiodarone, patients treated with an implantable cardioverter-defibrillator (ICD) in AVID had a maximal benefit in survival when the ejection fraction (EF) was between 20 and 34%. In CIDS, the group of higher risk (older than 70 years, EF less than 3.5%, and New York Heart Association class III-IV) presented a 50% RR of mortality. It has been demonstrated that the imbalance in beta-blocker use cannot explain the better survival in the ICD patients. After 3 years the recurrence of arrhythmia was 64% in the ICD group of the AVID trial. Patients enrolled after an episode of ventricular tachycardia were more likely to have appropriate therapy during follow-up. Older age, lower blood pressure, history of atrial fibrillation, diabetes, congestive heart failure, and prior pacemaker were parameters used for high-risk stratification. Conversely, inducibility of ventricular tachyarrhythmias on electrophysiology did not predict death. SUMMARY: Patients with ICD after ventricular tachyarrhythmias have a 28% RR in total mortality. Individuals with EF between 20 to 34% received the highest benefit with ICD therapy.     

恶性室性心律失常埋藏式心脏复律除颤器与药物治疗的对比研究

观察埋藏式心脏复律除颤器 (ICD)与药物对恶性室性心律失常的治疗效果 ,探讨其对心源性猝死的预防。94例患者 ,均有室性心动过速 (简称室速 )和 /或心室颤动等恶性室性心律失常发作史 ,其中冠心病 68例、原发性扩张型心肌病 2 6例。根据电生理心室程序刺激结果将患者分为药物治疗组 (A组 )、ICD组 (B组 )和慢频率室速药物治疗组 (C组 )。分别给予胺碘酮和 /或阿替洛尔药物治疗和ICD治疗。观察随访 1 ,2 ,5年的总生存率 ,不同左室射血分数 (EF)值亚组的生存率和心律失常性死亡的发生率。结果显示 ,随访 5年的总生存率C组明显低于A、B两组(P <0 .0 5 ) ,B组的低EF(≤ 0 .40 )值亚组的 5年生存率明显高于A、C两组的低EF值亚组 (P <0 .0 5 )。B组随访期间无心律失常死亡者 ,其心律失常性死亡事件的发生率明显低于A、C两组 (P <0 .0 5 )。结论 :ICD对于合并有恶性室性心律失常的心脏病人预防猝死的总体效果优于 β 阻断剂和胺碘酮等药物治疗。这尤其见于长期随访 (≥ 5年 )和伴有心功能不全 (EF值≤ 0 .40 )的病人。对于有过恶性室性心律失常发作史的患者 ,若心电生理检查不能诱发室速 ,在没有条件安装ICD时 ,胺碘酮与 β 阻断剂联合应用仍可在一定程度上减少心源性猝死的发生。     

Long-term follow-up of implantable cardioverter-defibrillator for secondary prevention in chagas' heart disease

Assessing the efficacy of implantable cardioverter-defibrillators (ICD) in patients with Chagas' heart disease (ChHD) and identifying the clinical predictors of mortality and ICD shock during long-term follow-up. ChHD is associated with ventricular tachyarrhythmias and an increased risk of sudden cardiac death. Although ChHD is a common form of cardiomyopathy in Latin American ICD users, little is known about its efficacy in the treatment of this population. The study cohort included 116 consecutive patients with ChHD and an ICD implanted for secondary prevention. Of the 116 patients, 83 (72%) were men; the mean age was 54 ± 10.7 years. Several clinical variables were tested in a multivariate Cox model for predicting long-term mortality. The average follow-up was 45 ± 32 months. New York Heart Association class I-II developed in 83% of patients. The mean left ventricular ejection fraction was 42 ± 16% at implantation. Of the 116 patients, 58 (50%) had appropriate shocks and 13 (11%) had inappropriate therapy. A total of 31 patients died (7.1% annual mortality rate). New York Heart Association class III (hazard ratio [HR] 3.09, 95% confidence interval 1.37 to 6.96, p = 0.0064) was a predictor of a worse prognosis. The left ventricular ejection fraction (HR 0.972, 95% confidence interval 0.94 to 0.99, p = 0.0442) and low cumulative right ventricular pacing (HR 0.23, 95% confidence interval 0.11 to 0.49, p = 0.0001) were predictors of better survival. The left ventricular diastolic diameter was an independent predictor of appropriate shock (HR 1.032, 95% confidence interval 1.004 to 1.060, p = 0.025). In conclusion, in a long-term follow-up, ICD efficacy for secondary sudden cardiac death prevention in patients with ChHD was marked by a favorable annual rate of all-cause mortality (7.1%); 50% of the cohort received appropriate shock therapy. New York Heart Association class III and left ventricular ejection fraction were independent predictors of worse prognosis, and low cumulative right ventricular pacing defined better survival.     

Cardiac death and stored electrograms in patients with third-generation implantable cardioverter-defibrillators

Objectives. We sought to utilize terminal stored intracardiac electrograms (EGMs) to study the electrophysiologic events that accompany mortality in patients with third-generation implantable cardioverter-defibrillators (ICDs).Background. Despite their ability to effectively terminate ventricular tachyarrhythmias, cardiac mortality in patients with ICDs remains high. The mechanisms and modes of death in these patients are not well understood.Methods. We retrospectively analyzed clinical data and stored EGMs from patients enrolled in the clinical trial of the Ventritex Cadence ICD. Of the 1,729 patients 119 died during 6 years of follow-up. The final recorded EGM was reviewed. Postimplant EGMs as well as 50 control EGMs were used to define normal EGM characteristics.Results. There were 36 noncardiac deaths (30%) and 83 cardiac deaths (70%). Of the cardiac deaths, 55 (66%) were nonsudden and 28 (34%) were sudden. When cardiac deaths were analyzed, 46 (55%) had no stored EGMs within 1 h of death, implying that the deaths were not directly related to tachyarrhythmias. In 37 cardiac deaths (18 nonsudden, 19 sudden), stored EGMs were present within 1 h of death. In these 37 deaths, the final EGM recorded was wide (>158 ms) in 33 (89%). Wide EGMs were interpreted as ventricular tachycardia in 27 and ventricular fibrillation in 6. In 13 of the 33 patients (39%) with wide EGMs, therapy was not delivered by the ICD, as it incorrectly detected a spontaneous termination of the arrhythmia. EGMs were significantly wider if recorded within 1 h, as compared with those recorded from 1 to 48 h before death (261 ± 124 vs. 181 ± 93 ms, p = 0.04).Conclusions. Only 37 patients (31%) who died after placement of an ICD had a stored EGM within 1 h of the time of death, suggesting that the majority of deaths (69%) were not the immediate result of a tachyarrhythmia. When EGMs were recorded, they were wide in 89% of patients. These wide EGMs most likely represent intracardiac recordings of electromechanical dissociation. Thus, of the 119 deaths, 112 (94%) were not the immediate result of a tachyarrhythmia.     

卡维地洛治疗扩张型心肌病心力衰竭患者的疗效

目的：观察卡维地洛治疗扩张型心肌病心力衰竭患者的临床疗效。方法：选择扩张型心肌病心力衰竭患者82例,采用随机分组的方法分为卡维地洛组（42例）和常规治疗组（40例）,卡维地洛组在常规治疗基础上加用卡维地洛3．125～25mg2次／d。比较两组左室舒张期末内径（LVEDd）、左室收缩期末内径（LVEsd）、左房内径（LAD）、左室射血分数（LVEF）、6min步行距离（6MWD）等指标变化情况。结果：治疗6个月后,两组患者心功能均有改善,卡维地洛组总有效率显著高于常规治疗组（90．5％比72．5％,P〈0．05）;两组治疗后患者的LVEDd、LVESd、LVEF及6MWD均有显著改善（P〈0．05）,且与常规治疗组比较,卡维地洛组治疗后患者的LVEDd[（59．1±9．6）mm比（54．2±10．2）mm]、LVESd[（46．1±8．7）mm比（41．4±12．2）mm]显著缩小,LVEF[（42．1±10．5）％比（48．4±9．6）％]及6MWD[（264．52±51．23）m比（309．26±45．24）m]显著增加（P均〈0．05）。结论：在常规治疗基础上加用卡维地洛可明显改善扩张型心肌病心力衰竭患者的疗效。     

永久起搏器和埋藏式心脏复律除颤器（ICD）在遗传性长QT综合征患者中的应用

目的总结合并窦性心动过缓的遗传性长QT综合征（以下简称遗传性LQTS）患者植入永久起搏器和埋藏式心脏复律除颤器（以下简称ICD）的治疗效果,对比分析这两种治疗在预防患者猝死中的差异。方法对我院从2003年6月到2013年6月出院诊断为遗传性LQTS合并窦性心动过缓、植入了永久起搏器或ICD的全部21例患者,结合门诊、电话和程控随访了解患者的生存状况、手术并发症以及晕厥、室性恶性心律失常的发作情况。结果起搏器组男性2例,女性9例,年龄39.3±14.3岁,随访时间50.6±26.3个月,1例患者猝死,2例患者再发晕厥前兆,其中1例最终更换为ICD。ICD组男性2例,女性8例,年龄34.5±11.9岁,随访时间61.4±43.5个月,3例患者接受了ICD的适当治疗,另2例患者接受了ICD的不适当治疗,1例患者术后出现囊袋感染,1例患者更换为永久起搏器。治疗有效率在起搏器组及ICD组分别为72.7%（8/11）和100.0%（10/10）,未达到统计学差异（p=0.21）。不良事件发生率在起搏器组及ICD组分别为27.3%（3/11）和30.0%（3/10）,也未达到统计学差异（p=0.63）。结论对于不能植入ICD的合并窦性心动过缓的遗传性LQTS患者,植入永久起搏器可能是一个较好的替代方法,但对于QTc≥539ms的患者,只有植入ICD才能预防猝死。植入ICD后长期无心脏事件发生的患者,根据患者意愿,可考虑更换为永久起搏器。     

Roles and indications for use of implantable defibrillator and resynchronization therapy in the prevention of sudden cardiac death in heart failure

Implantable devices are indicated in the primary and secondary prevention of potentially life-threatening ventricular tachyarrhythmias in patients with heart failure. Early studies, including the landmark MADIT trials, showed that implantable cardioverter–defibrillator (ICD) and cardiac resynchronization therapy (CRT) devices can play a significant role in aborting and preventing ventricular arrhythmias, respectively, that can cause sudden cardiac death. To this day, there have been a number of randomized controlled trials, with respective substudy analyses, that have attempted to better understand the indications for these interventions in patient care. Here, we summarize the major results of these studies, and we discuss the role of ICD therapy for both ischemic and non-ischemic cardiomyopathy, emerging evidence in support of wearable defibrillators, and the impact of modified ICD programming strategies on patient outcomes. Regarding CRT therapy, the phenomenon of ventricular reverse remodeling is an important prognostic indicator in preventing future ventricular tachyarrhythmia episodes. In summation, we provide an overview of the possible selection criteria that can be used in identifying appropriate patients for ICD and/or CRT therapy, as supported by the data.     

Role of nonsustained ventricular tachycardia and programmed ventricular stimulation for risk stratification in patients with idiopathic dilated cardiomyopathy

Background: The prognostic role of asymptomatic nonsustained ventricular tachycardia (NSVT) and programmed ventricular stimulation (PVS) in patients with idiopathic dilated cardiomyopathy (IDC) remains controversial. Methods: The prognostic significance of ventricular arrhythmias, ejection fraction, NYHA class, atrial fibrillation and age for overall and sudden death mortality was prospectively studied in 157 patients with IDC (group 1) free of documented sustained ventricular arrhythmia and syncope. In 99 patients with asymptomatic NSVT (group 2), PVS with 2 – 3 extrastimuli was performed. Non-inducible patients were discharged without specific antiarrhythmic therapy, whereas those with inducible monomorphic ventricular tachycardia were implanted with an ICD. Results: In group 1, 48% of patients had NSVT. Overall and sudden death mortality were significantly higher in patients with NSVT (34.2 vs. 9.8%, p = 0.0001 and 15.8 vs. 3.7%, p = 0.0037; follow-up 22 ± 14 months). Multivariate analysis revealed that NSVT independently predicts both overall and sudden death mortality (p = 0.0021 and .0221, respectively; adjusted for EF, NYHA class and age). In group 2, inducibility of sustained ventricular tachyarrhythmia was 7%, but sustained monomorphic VT occurred in 3% only. Two of 7 inducible patients experienced arrhythmic events during a follow-up of 25 ± 21 months (positive predictive value 29%). Overall and sudden death mortality were 29% and 0% in the inducible group vs. 17 and 4% in the non-inducible group. Both overall and sudden death mortality were signi.cantly lower in non-inducible patients from group 2 as compared to patients from group 1 with NSVT (p = 0.0043 and 0.0048), most likely due to a more common use of betablockers and a higher EF in the former group (p < 0.001, respectively). Conclusions: In patients with IDC, NSVT independently predicts both overall and sudden death mortality. Due to a low inducibility rate and a poor positive predictive value, PVS seems inappropriate for further arrhythmia risk assessment. However, in spite of documented NSVT, the incidence of SCD in patients on optimized medical treatment including betablockers seems to be very low, questioning the need for specific arrhythmia risk stratification. Received: 21 August 2002, Returned for revision: 24 September 2002, Revision received: 8 October 2002, Accepted: 7 November 2002, Published online: 12 May 2003 Correspondence to: R. Becker, MD     

An overview of arrhythmias and antiarrhythmic approaches

Although treatment of cardiac arrhythmias has been revolutionized in the past decade, patients with atrial fibrillation (AF) still represent a major challenge. With the graying of the population, AF is increasing in prevalence and is responsible for significant morbidity, mortality, and health care expenditures. Drug therapy will be required for the majority of patients with this disorder. Patients with ventricular tachyarrhythmias represent the other major challenge to the cardiac electrophysiologist. The use of implantable cardioverter-defibrillators (ICDs) has reduced the sudden death mortality to 1% or less per year in patients at risk of dying from a ventricular tachyarrhythmia. Unfortunately, high-risk patients who receive an ICD are only a small proportion of the patients who die suddenly each year. Considering the number of at-risk patients, it is likely that drug therapy will remain the mainstay of treatment of patients with ventricular tachyarrhythmias. Therefore, the major challenge is to recognize patients at risk and treat them with antiarrhythmic drugs to prevent sudden cardiac death. Consequently, it has become clear that we have come to a crossroad with regard to antiarrhythmic drugs. Our knowledge of the molecular biology of cardiac ion channels, electrophysiology, and emerging antiarrhythmic drugs provides us an opportunity to create new pharmacologic stratagems.     

慢性心力衰竭患者QRS时间延长的临床意义

目的评价慢性心力衰竭患者心电图QRS时间延长的临床意义。方法将入选的620例慢性心力衰竭患者按QRS时间分为≥120ms组（n=120）和〈120ms组（n=500）,比较两组患者QRS时间与左心室射血分数（LVEF）、左心室短轴缩短分数（LVFS）、NYHA心功能分级、左心房左心室大小、二尖瓣反流、左心室壁厚度和住院死亡率。结果①≥120ms组QRS时间（143±21）ms,〈120ms组为（89±12）ms;②〈120ms组LVEF及LVFS分别为（47．02±16．13）％、（22.85±10．34）％,均较≥120ms组（37．00±13.91）％和（15．65±8．83）％大（P〈0．01）;⑨两组患者NYHA心功能分级差异无统计学意义（P〉0．05）;④≥120ms组左心房内径、左心室舒张末期内径较〈120ms组大（P〈005或001）;⑧≥120ms组二尖瓣反流率（82．1％）较〈120ms组（67．5％）高;⑧两组患者左心室壁厚度和住院死亡率差异均无统计学意义（P〉0.05）。结论心电图QRS时间可作为判断慢性心力衰竭患者病情的一项指标。