无心房颤动患者腔静脉电活动特性的研究

目的探讨无心房颤动(AF)患者腔静脉内的电活动及其传导特性。方法选择32例无AF患者,记录腔静脉电位分布和腔静脉与心房的电连接类型,观察右房(RA)及腔静脉起搏时局部电活动特性。结果28例(87.5%)存在上腔静脉(SVC)电位,其电位分布:前侧壁14例、前壁12例、环状2例,其电连接类型:单束状10例(31.3%)、双束状16例(50.0%)、环状2例(6.3%);只有5例(15.6%)存在下腔静脉(IVC)电位,电位分布于前侧壁,3例呈单束状、2例呈双束状电连接。RA起搏时RA-SVC的有效不应期(ERP)为202±21ms,SVC起搏时SVC-RA的ERP为228±15ms,两者比较差异有显著性(P<0.05);RA起搏时RA-IVC的ERP为190~230ms(中位数M=195ms),IVC起搏时仅1例患者存在IVC-RA传导,其ERP为200ms。结论无AF患者腔静脉存在电位,其与右房表现为单束状、双束状或环状电连接。

Prevalence and properties of electrical activity in vena cava in patients without atrial fibrillation

Objective To investigate the characteristics of electrical activity and conductivity in vena cava in patients without atrial fibrillation (AF). Methods 32 cases without AF were studied. The vena cava potentials in vena cava were recorded, the patterns of the electrical connection between atrium and vena cava were analysed and effective refractory period(ERP) in right atrium and vena cava was detected by programmed S_1S_2 stimulation respectively in vena cava and right atrium. Results Potentials of SVC were recorded in 28 cases(87.5%),in 14 cases were localized in front and side wall,in 12 cases in front wall and in 2 cases in circumferential distribution;One bundle connection pattern was found in 10 cases(31.3%), two bundle connection pattern in 16(50.0%)and circumferential connection pattern in 2(6.3%). Potentials of IVC were recorded in only 5 cases(15.6%) in front and side wall with one bundle connection pattern in 3(9.4%)veins and two bundle connection pattern in 2(6.3%). The ERP of RA-SVC was 202±21 ms during artial pacing, and that of SVC-RA was 228±15 ms during SVC pacing. The former was shorter than the latter(P<0.05). The ERP of RA-IVC was 190~230 ms(M=195 ms) during atrial pacing, while IVC-RA conduction was found in only 1 case during IVC pacing whose ERP was 200 ms. Conclusions Vena cava potentials can be recorded in patients without AF, which show one bundle, two bundle or circumferential electrical connection between atrium and vena cava.