不同房室间期对双腔起搏左室收缩功能的影响

为探讨双腔起搏不同房室间期对左室收缩功能的影响及最佳房室间期 ,选择 18例置入DDD起搏器的病窦综合征患者 ,在DOO起搏方式下随机将房室 (AV)间期程控为 10 0 ,130 ,15 0 ,170 ,2 0 0ms,在超声心动图下观察左室收缩功能指标 ,每次测量间隔 5min以上。结果 :AV间期为 15 0ms时左室收缩功能最好 ,与AV间期为 10 0ms时相比 ,左室收缩功能明显改善。以心输出量 (CO)为标准 ,18例中有 9例AV间期在 15 0ms时CO最佳 ,5例在 2 0 0ms时CO最佳 ,3例在 170ms时CO最佳 ,1例在 130ms时CO最佳 ;以CO为标准 ,DOO起搏方式最佳AV间期为 16 6±2 4ms。结论 :双腔起搏的AV间期对左室收缩功能有重要的影响 ,以CO为标准 ,个体化地选择双腔起搏的最佳AV间期对改善患者的心脏功能有重要的意义。     

Compromised atrial coronary anatomy is associated with atrial arrhythmias and atrioventricular block complicating acute myocardial infarction

BACKGROUND: The relevance of the atrial coronary anatomy in the pathogenesis of atrial arrhythmias and atrioventricular (AV) block complicating acute myocardial infarction (AMI) remains unclear. OBJECTIVES: We evaluated the location of the infarct-related coronary lesion relative to the principal atrial branches (ie, sinoatrial nodal, AV nodal, left atrial circumflex) in 454 patients with ST-elevation AMI in the CAPTORS II trial. METHODS: Patients underwent systematic 60-minute postfibrinolytic angiograms, and coronary anatomy was correlated with evidence of atrial arrhythmias and AV block on sequential electrocardiograms. RESULTS: Patients with either sinoatrial nodal or left atrial circumflex compromise (n = 34) had a higher incidence of "early" (ie, up to 90 minutes postfibrinolysis) atrial arrhythmias vs those without (23.5% vs 7.1%; P = .004). Patients with AV nodal compromise (n = 207) had a higher incidence of "early" AV block vs those without (12.1% vs 3.6%; P = .001). CONCLUSION: These findings support the etiological role of acute atrial ischemia in the development of early atrial arrhythmias and AV block complicating AMI.     

阵发性室上性心动过速(SVT)及房室传导阻滞(AVB)伴胸痛或心肌缺血患者冠状动脉造影结果分析

目的　探讨临床诊断为阵发性室上性心动过速 (SVT)及房室传导阻滞 (AVB)伴胸痛或心肌缺血患者心肌缺血的病因及其临床意义。方法　 5 1例 SVT或 AVB伴不同程度胸痛、胸闷、气短或心肌缺血患者 ,在介入检查或治疗的同时行冠状动脉造影和左心室造影术 ,分析冠状动脉造影结果、术后诊断及疾病转归情况 ,并将其中冠状动脉造影正常者及有病变的部分临床资料对比分析。结果　冠状动脉造影正常者 37例 (占 72 .5 % ) ,其中女性 2 0例 (占正常者 5 4 .1% )。 SVT 14例 (占所有 SVT病人的 77.8% ) ,AVB 2 3例 (占所有 AVB病人的 6 9.7% )。单纯传导系统退行性 AVB或合并房性心律失常 19例 (19/ 33,占 5 7.6 % ) ,其中 4例伴退行性瓣膜病变 ,6例伴冠状动脉粥样硬化 ;AVB伴冠心病者 4例 (4/ 33,占 12 .1% )。SVT病人中 ,冠状动脉造影阳性并确诊为冠心病者仅有 2例 (2 / 18,占 11.1% ) ,而大多数不伴器质性心脏病 (14 / 18,占 77.8% )。大多数 AVB病人在安置起搏器后症状及缺血改善。吸烟、血糖、L DI- C及 L p(a)在冠状动脉造影正常与异常之间差异显著 (P分别 <0 .0 1及 <0 .0 5 )。结论　大多数SVT及 AVB病人缺乏冠心病基础 ,所以有典型心绞痛的 SVT及 AVB病人 ,尤其 4 0岁以上男性 ,才有必要在做介入检查或治疗的     

Near miss sudden cardiac death on a young patient with repaired atrioventricular septal defect

Patients with congenital heart disease often face the prospect of long-term haemodynamic or arrhythmic complications for which lifelong follow-up in specialist adult congenital heart disease (ACHD) centres is required. We describe the case of a 25-year-old man with repaired atrioventricular septal defect who was referred to our centre after a ventricular fibrillation arrest. Serial echocardiograms in previous years had shown progressive severe left ventricular outflow obstruction, but the patient had not been operated on as he was deemed asymptomatic and reluctant to consider surgery. Management and criteria for further intervention in ACHD patients often differ from those of patients with acquired heart disease and reliance on symptoms alone is not good practice and may prove catastrophic.     

Cryoablation versus radiofrequency ablation for treatment of pediatric atrioventricular nodal reentrant tachycardia: Initial experience with 4-mm cryocatheter

BACKGROUND: Initial reports have shown cryoablation to be safe and efficacious for treatment of atrioventricular nodal reentrant tachycardia (AVNRT). No direct comparisons of cryoablation vs radiofrequency (RF) catheter ablation in pediatric patients have been made. OBJECTIVES: The purpose of this study was to compare the outcomes of cryothermal vs RF catheter ablation for treatment of AVNRT in pediatric patients. METHODS: We retrospectively reviewed consecutive ablation procedures for treatment of AVNRT at a single arrhythmia center. The RF group consisted of patients who underwent RF ablation from 2002 until cryothermy became available. The cryoablation group consisted of patients who underwent cryothermal ablation from 2004 to 2005. The groups were compared for procedural and electrophysiologic outcomes. RESULTS: RF (n = 60, age 14 +/- 4 years) and cryoablation (n = 57, age 14 +/- 4 years) groups had similar demographic and baseline parameters. Procedural times were shorter in the RF group (RF ablation 112 +/- 31 minutes vs cryoablation 148 +/- 46 minutes, P < .001). Fluoroscopy times were comparable (RF ablation 21 +/- 15 minutes vs cryoablation 20 +/- 13 minutes, P = .77). In an intention-to-treat analysis, success of the procedure was 100% for RF ablation and 95% for cryoablation (P = .11). No permanent AV block occurred in either group. Recurrence rates were higher for the cryoablation group, but this did not reach statistical significance (RF ablation 2% vs cryoablation 8%, P = .19). CONCLUSION: Cryoablation appears to be similar to RF for ablation of AVNRT with respect to short-term efficacy and safety of the procedure in a pediatric population. Recurrence rates are higher with cryoablation.     

Atrioventricular nodal re-entrant tachycardia with QRS voltage and cycle length alternation and aberrant conduction due to two distinct antegrade slow pathways.

QRS voltage and cycle length alternation can be seen during supraventricular re-entrant tachycardias, especially in atrioventricular (AV) re-entrant tachycardia. We present a case of a 20-year-old man, in which AV nodal re-entrant tachycardia (AVNRT) shows alternation of QRS voltage and cycle length, as well as right bundle branch block aberration due to a re-entrant circuit using two distinct, beat-to-beat alternating slow AV nodal pathways antegradely and a single fast pathway retrogradely. Although more than one antegrade slow pathway exists, creation of a single lesion at the right posterior atrial septum using the conventional right-sided approach successfully eliminated AVNRT.     

Haemodynamic significance of the atrioventricular plane displacement in patients with coronary artery disease.

Echocardiographic quantitative assessment of the atrioventricular plane displacement (AVPD) in systole towards the apex has been used to estimate global left ventricular (LV) function. The study population consisted of 106 patients with coronary artery disease (CAD) with or without previous myocardial infarction and 40 age-matched healthy subjects. The AVPD was recorded from the apical four- and two-chamber views at four sites corresponding to the septal, lateral, anterior and posterior walls of the left ventricle. A mean displacement (AVmean) was calculated from the above sites. AVmean was significantly decreased in patients with CAD compared to healthy subjects (P less than 0.001). In patients in whom the left ventricular ejection fraction (LVEF) was calculated from cineangiograms a good correlation between AVmean and LVEF was found (r = 0.89, P less than 0.001, SEE = 6.4). Selecting an AVmean of 10 mm or more to define a normal LVEF (greater than or equal to 55%) resulted in a sensitivity of 92% and a specificity of 87% in predicting a normal versus abnormal left ventricular systolic function. It is concluded that the ease of recording the AVPD by echocardiography provides a simple and valuable noninvasive method to assess global left ventricular function in patients with CAD.     

房室结慢径改良发生Ⅲ度房室传导阻滞的探讨

目的：探讨房室结慢径改良发生Ⅲ度房室传导阻滞（AVB）的特异性心电改变及预防，方法：232例房室结折返性心动过速（AVNRT）患者分三组：一组：81例，任何一次放电过程中无特异性心电改变；二组：82例，有一次或一次以上的放电过程中特异性心电改变701次，且放电时间小于3s，三组：69例，有一次或一次以上的放电过程中特异性心电改变97次，但放电时间大于3s，结果：232例患者均消融成功，其中发生一次性Ⅲ度AVB11例，永久性Ⅲ度AVB7例，结论：射频消融术改良房室结慢径时可发生Ⅲ度AVB，但只要我们术中发现特异性心电改变立即停止放电并选择适当的消融方法。可将Ⅲ度AVB降低到最低限度。     

射频消融疑难的房室结折返性心动过速(附三例分析)

回顾分析２２４例房室结折返性心动过速的射频消融结果，３例消融未成功，占１．３％。其中１例消融房室结造成Ⅲ度房室阻滞后仍有心动过速发作，提示房室结双径路下部共同通道的存在。消融不成功的原因可能为慢径不是一组纤维，且在解剖上快、慢径极为邻近，易同时受损。提示在遇到消融极为困难的病例，应酌情放弃消融，考虑更恰当的治疗方式，以避免因刻意追求消融成功而导致永久性房室阻滞的发生。