不同负荷特发性室性早搏对心脏结构和功能的影响

目的探讨不同负荷特发性室性早搏(简称室早)对心脏结构和功能的影响。方法入选102例特发性室早患者,根据室早数量与24 h总心搏的比值,将入选患者分为室早负荷<10%组(低负荷组),10%～20%组(中等负荷组),>20%组(高负荷组)。采用二维心脏超声分别测量左室射血分数(LVEF),左室舒张末期内径(LVEDD),左室收缩末期内径(LVESD)值,并检测以上患者血清N-末端脑钠肽(NT-proBNP)水平。结果室早负荷与LVEDD(r=0.27,P=0.003)、LVESD(r=0.31,P=0.001)大小、血清NT-proBNP水平呈正相关(r=0.21,P=0.02),和LVEF呈负相关(r=0.21,P=0.02);高负荷组与低负荷组、中等负荷组相比,LVEDD、LVESD值明显增大,LVEF值明显降低(P<0.05),而NT-proBNP的升高无显著性。结论随着室早负荷的增大,左室的结构与功能出现重构性变化。     

以双向阻滞作为阵发性心房颤动肺静脉电隔离终点的临床研究

目的 评价以左心房-肺静脉电联系双向阻滞作为环肺静脉消融电隔离术终点对阵发性心房颤动(房颤)导管消融疗效的影响.方法 在76例阵发性房颤患者导管消融达到左心房-肺静脉传入阻滞后,分别于每根肺静脉内起搏评价肺静脉-左心房传导情况.据此分为双向阻滞组(传入与传出均阻滞)和传入阻滞组,随访观察房颤导管消融的临床疗效.结果 76例均完成导管消融术,306根肺静脉(2例患者存在右中肺静脉)均达到左心房-肺静脉电学传入阻滞之传统终点.18例消融术后左心房-肺静脉传导呈双向阻滞,58例仅传入阻滞.平均随访(6.85±1.08)个月,1次消融成功率为77.63％.其中,双向阻滞组为83.33％,传入阻滞组为75.86％,两组相比差异无统计学意义(P＞0.05).术后房性心动过速发生率5.26％(4/76),无心脏压塞、脑栓塞、左心房食管瘘等并发症以及死亡发生.结论 以左心房-肺静脉传导双向阻滞为房颤导管消融终点治疗阵发性房颤的策略似乎临床疗效较好.     

桥粒芯胶蛋白-2基因沉默对P19细胞向心肌细胞诱导分化的影响

目的 探讨在P19细胞诱导分化成心肌细胞过程中,桥粒芯胶蛋白-2（DSC2）基因沉默对其的影响。方法 设计并合成针对DSC2基因编码区的干扰序列,构建真核细胞表达质粒并转染P19细胞。荧光定量聚合酶链式反应（RT-PCR）和蛋白免疫印迹（Western blot）技术检测DSC2在mRNA和蛋白水平表达变化,筛选出沉默效率最佳的细胞株。二甲基亚矾诱导分化为心肌细胞,观察其超微结构和细胞凋亡等改变,以及对纤维化与脂肪化相关基因mRNA水平表达的影响。结果 成功构建了5种ShDSC2重组质粒,转染P19细胞并获得稳定转染细胞株,筛选出对DSC2基因mRNA水平（69. 47% vs 0,P〈0. 01）和蛋白水平表达（65. 62% vs 0,P〈0. 01）的抑制效率最显著的ShDSC2鄄613组,并成功诱导分化为心肌样细胞后,电镜扫描显示后者细胞出现脂滴、空泡样变性、线粒体肿胀及嵴消失,流式细胞仪检测提示细胞凋亡显著增加,RT鄄PCR示纤维化相关基因（Collal、Colla2、Col3a1）与脂肪化相关基因（Adiponectin、PPAR-γ、C/EBP-α）的mRNA表达均显著升高。结论 建立能有效抑制DSC2表达的P19细胞株并分化为心肌样细胞,表现出与致心律失常型右室心肌病（ARVC）患者病理和分子生物学特点相似的表型特征,提示其可作为深入研究ARVC致病机制的前体细胞。     

磁导航系统遥控导管消融治疗右心室流出道室性心动过速/室性早搏

目的：探讨应用磁导航遥控导管消融治疗右心室流出道起源的室性心动过速/室性早搏（ RVOT-VT/PVCs）的安全性和有效性。方法2008年11月至2009年11月,在南京医科大学第一附属医院心血管内科行体表心电图检查,诊断为RVOT-VT/PVCs的患者共16例[女12例,男4例,平均年龄（44±15）岁],结合应用非接触标测系统和起搏标测确定靶点,磁导航遥控磁导管实施消融术,消融失败者改为手控导管消融。结果10例（63%）患者使用磁导航消融成功,6例需手控导管消融,1例术后出现动静脉瘘。平均放电（3．9±1．6）次,放电时间（240±33） s,总手术时间为（190±42） min,总X线曝光时间为（4．8±2．6） min,术者X线曝光时间平均为（3．2±2．0） min,磁导航系统遥控导管X线曝光时间为（1．6±1．0） min。结论应用磁导航系统结合非接触标测系统可安全、有效地实施遥控导管消融治疗RVOT-VT/PVCs,并可减少术者和患者的X线曝光时间。     

血管迷走性晕厥单中心294例结果分析

目的:对单中心33个月所做的直立倾斜试验(HUTT)结果进行分析并探讨健康教育对HUTT阳性患者再发晕厥次数的影响。方法:收集从2015年2月至2017年11月因反复晕厥或反复出现晕厥前兆在南京医科大学第一附属医院就诊并进行HUTT患者294例。根据HUTT中患者心率与血压的变化,196例HUTT呈阳性,其中混合型血管迷走神经性晕厥(Ⅰ型)146例,心脏抑制型血管迷走神经性晕厥(Ⅱ型)14例,血管抑制型迷走神经性晕厥(Ⅲ型)36例。分析各型患者HUTT阳性率并对健康教育前后HUTT阳性结果患者晕厥发生次数的差异进行比较。结果:在294例行HUTT检测的患者中,有196(66.7%)例患者出现血管迷走性晕厥,其中I型、Ⅱ型、Ⅲ型血管迷走性晕厥分别有146例(74.5%)、14例(7.1%)、36例(18.4%)。年龄>60岁患者HUTT阳性率明显高于年龄<40岁患者(77.1%vs.57.1%,P<0.01)。在196例HUTT阳性患者中,80例(40.8%)患者接受随访,随访患者接受健康教育前后,患者晕厥次数中位数从2(四分位数间距IQR:1~4)次降到0(IQR:0~0)次(P<0.001),差异有统计学意义。结论:HUTT证实,血管迷走性晕厥患者中以混合型血管迷走神经性晕厥为主,年龄较大患者HUTT阳性率较高,随访结果提示健康教育可以减少此类患者再发晕厥风险。     

高分辨弥散加权成像在心房颤动导管消融围术期无症状脑栓塞发生的评估价值

目的比较高分辨弥散加权成像（hDWI）和常规DWI（cDWI）检测心房颤动（房颤）导管消融相关无症状性脑栓塞（ACE）的发生率及其特征。 方法连续入组2018年11月至2018年12月南京医科大学第一附属医院的32例房颤消融患者,以及上海市东方医院2019年1月至2019年2月的18例房颤消融患者。消融前24 h进行头颅高分辨率DWI检查以除外近期脑栓塞事件,消融后48 h内重复hDWI和cDWI检查。比较同一患者消融术后hDWI与cDWI中ACE的发生率、数量、大小和位置。 结果与cDWI相比,hDWI显示急性ACE的发生率更高（70%对42%,P<0.001）,ACE病灶数量明显更多（102对42,P < 0.001）,且hDWI测量的病灶尺寸较大（5.42 mm对4.21 mm,P < 0.001）。多因素回归分析显示,左心室射血分数受损（P=0.047）和术中激活凝血时间较低（P=0.003）与ACE发生相关。 结论hDWI能够更好地显示房颤消融相关ACE的发病情况及病灶特点。在评估ACE的研究中应考虑磁共振设置。     

磁导航遥控射频导管消融治疗房室结折返性心动过速的初步体会

Objective To evaluate the safety and feasibility of remote radiofrequency catheter ablation of atrioventricular nodal reciprocating tachycardia (AVNRT) using the magnetic navigation system (MNS). Methods A total of 37 patients[female 29, mean age (44 ± 15 )years]with documented AVNRT were enrolled in this study from March 2007 to June 2009. A 4 mm tip magnetic mapping and ablation catheter ( Helios Ⅱ ,Stereotaxis, USA),which was remotely controlled by the MNS (Niobe Ⅱ , Stereotaxis, USA), was used for both mapping and ablation. Conventional slow pathway modification with focal ablation at the fight posterior septum was first performed in all patients. If it was failed, linear lesions at the base of Koch' s triangle was then done. Results After ablation, AVNRT was non-inducible in all 37 patients without any complication except one case experienced transient first degree AV block. Focal ablation was performed in 34 patients, and linear ablation strategy was used in the remaining three cases to achieve the end point. Among all the 37 patients, slow pathway ablation was achieved in 14, whereas slow pathway modification was reached in the remaining 23 cases.The mean procedural time, the RF deliveries, the duration of RF application were ( 120 ± 32) min, (2. 9 ± 1.6)times, ( 130 ± 33 )s,respectively. The total fluoroscopy time and the physician X-ray exposure time were(5.3 ±2. 7)min and(2.9 ± 1.1 ) min,respectively. There was no significant change of the AH interval,the HV interval,and the atrioventricular nodal conduction refractory period after ablation. Compared with the first 18 patients, the mean procedural time, the total fluoroscopy time and the X-ray fluoroscopy time during magnetic navigation were significantly decreased in the later 19 patients (P ＜0. 001 ). It indicated that the learning curve of remote catheter ablation using the MNS is short. Conclusion Remote catheter ablation using the MNS to cure AVNRT is safe and effective with short learning curve and decreasing X-ray exposure time for interventional physicians.     

三维电解剖标测指导疑难右侧游离壁旁路的导管消融

Objective To demonstrate the electroanatomic substrates of right-sided free wall (RFW)accessory pathways (APs) which were refractory to conventional catheter ablation utilizing three-dimensional (3D) mapping. Methods Seventeen patients with RFW APs that failed initial conventional catheter ablation(s)by a mean of 1～3(1.8±0.6) attempts were enrolled in the study. Electroanatomic mapping of the right atrium was performed during right ventricular pacing in 14 patients and orthodromic reciprocating tachycardia in 3patients. Radiofrequency energy was delivered via irrigation catheter to the earliest atrial activation site. Results The earliest atrial activation site, which represented the atrial insertion of the APs, was separated from the tricuspid annulus by an average of 9 ～ 20 ( 13.6 ± 3.4 ) mm, and the local activation time was 18 ～ 80(31.5±16.3) ms earlier than that of the corresponding annular point. The target electrogram demonstrated AP potential in fourteen patients and ventriculoatrial fusion in the rest three. Accessory pathway was blocked in one case during moving the catheter and RF ablation delivery on the areas. One patient exhibited an AP with wide branching on the atrial side during mapping. RF ablation with an irrigated catheter successfully interrupted AP conduction in remaining 16 patients without complications. After a mean follow-up of 3 ～ 41 (18.6±12.7) months, there were no recurrences of ventricular preexcitation or episodes of tachycardia. Conclusion RFW APs refractory to conventional catheter ablation might be due to unique anatomic AP features such as more epicardial course at the annulus level with atrial insertion distance from the tricuspid annulus. Electroanatomic mapping is helpful to accurately localize the atrial insertion sites of these APs and facilitates catheter ablation.     

碎裂QRS波在致心律失常性右心室心肌病诊断中的价值

Objective To evaluate diagnostic value of fragmented QRS complex (fQRS)in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). Methods Forty-three patients [33 men, aged (40. 4 ± 13.9)years]meet the ISFC/ESC diagnostic criteria for ARVC were enrolled in this study. A standard twelve-lead electrocardiogram was obtained during the resting status. Characteristics of fQRS were detailedly studied by three doctors independently. A comparison of the prevalence among fQRS, epsilon wave and T wave inversion( TWI )in the right precordial leads exceeding V3 was done. Results Most fQRS could be found in the inferior leads (44. 3% ) and the right precordial leads (24. 2% ). Within the QRS complex, the prevalence of fQRS in the R wave was significantly higher than it in the S wave(58. 4% vs 32. 9% ,Z =4. 30,P ＜0. 01 ).fQRS could be found in a total of 31 of 43 cases( mean 4. 6 ± 1.7 ( range 2 to 9) per patient). The prevalence of fQRS was significantly higher than that of epsilon wave ( 73.8% vs 30. 2%, Z = 3.67, P ＜ 0. 01 ) and TWI (73.8% vs41.9% ,Z =2. 61 ,P＜0. 01 ). Conclusion fQRS was a common electrocardiographic abnormality,and most was found in the inferior and right precardial leads in patients with ARVC. It may be used as an important noninvasive preliminary screening electrocardiographic criteria.