醫(yī)學(xué)免費(fèi)論文:高頻左心房起搏制作兔慢性房顫模型及電生理特性研究
【摘要】 建立兔左心房高頻起搏心房顫動(AF)動物模型,并進(jìn)行電生理特性研究。 【方法】 16只健康新西蘭兔隨機(jī)分為:對照組和起搏組兩組。兩組均在左心房外膜縫合固定一起搏電極,起搏組以1 000 min-1的頻率進(jìn)行高頻起搏;對照組不起搏。采用心外膜程序起搏技術(shù)測定心房肌的電生理特性。 【結(jié)果】 ①起搏組3周后房顫誘發(fā)率87.5%,與對照組比較統(tǒng)計學(xué)有差異(P < 0.01),其中持續(xù)性AF 3/8例;②起搏組經(jīng)心外膜程序起搏,在高頻刺激1 h、1周、3周后心房有效不應(yīng)期(ERPA)均縮短,與對照組比較有顯著統(tǒng)計學(xué)差異(P < 0.01);③頻率適應(yīng)性方面,起搏組表現(xiàn)為頻率適應(yīng)不良,在3周時最明顯,與對照組比有統(tǒng)計學(xué)意義(P < 0.05);④起搏組3周后P波時限比對照組延長,但兩者比較無統(tǒng)計學(xué)差別(P﹥0.05);⑤起搏組1 h至3周,ERPA縮短、相對不應(yīng)期(RRPA)延長,與對照組比較統(tǒng)計學(xué)有差異(P < 0.01)、早搏刺激的心房間傳導(dǎo)時間(IACD)延長,與對照組比較統(tǒng)計學(xué)上無差別(P﹥0.05)!窘Y(jié)論】 兔左心房高頻起搏能有效建立慢性AF動物模型;主要電生理改變有:ERPA縮短、頻率適應(yīng)不良、P波時限延長。
【關(guān)鍵詞】 心房刺激; 心房顫動; 動物模型; 心房電生理特性醫(yī).學(xué).全.在.線m.52667788.cn
Induction of Atrial Fibrillation by Left Atrial High-Frequency Pacing and Investigationof Electrophysiological Characteristics of Atrial in RabbitsLIU Li-juan, ZHENG Dong-dan, LI Shu-bing, PAN De-mao, WANG Qiang, ZHANG Wei1, GAO Xiu-ren1. Department of Cardiology; 2. Department of Emergency,Huangpu Hospital, The First Affiliated Hospitalof Sun Yat-Sen University, Guangzhou 510700, ChinaAbstract: 【Objective】 To establish the model of atrial fibrillation (AF) by high-frequency pacing and explore the atrial electrophysiological characters in rabbits. 【Methods】 Sixteen rabbits were randomly divided into pacing group and control group. A pacing electricity pole was fixed under the adventitia of left atrium in all experiment animals. The pacing group was stimulated in a frequency of 1 000 bpm and the control group underwent without pacing stimulation. The technique of programmed stimulating was used to measure electrophysiological indexes of atrial in the groups. 【Results】 ①87.5% of the animals in pacing group suffered from AF under 3 weeks high frequency pacing, which was significantly higher than that of control group (P < 0.01). Permanent AF was found in 3 out of 8 cases. ②Atrial effective refractory period (ERPA) was statistically shortened in the pacing group comparing to the control group after 1 hour, 1 week and 3 weeks stimulating (P < 0.01, respectively). ③The pacing group showed a significantly poor performance of frequency adaptability comparing to the control group after 3 weeks stimulating (P < 0.05). ④The P-wave interval was longer in pacing group than that of the control group after 3 weeks pacing, but no significantly different was found (P > 0.05). ⑤ERPA was obviously shortened and RRPA was significantly prolonged in the pacing group after 1 hour to 3 weeks stimulating (P < 0.01), but there was no difference significantly in inter-atrial conduction defect (IACD) between the two groups (P﹥0.05). 【Conclusions】 The animal model of chronic atrial fibrillation could be successfully established by high frequency pacing of atrial in rabbits. The apparent electrophysiological changes of this model include: the frequency inadaptability, shortening of ERPA and extension of P-wave interval.
Key words: artrial stimulation; atrial fibrillation; animal model; artrial electrophysiological charactoristics
2 結(jié) 果