CAJ | 학술논문

目的在迷走神经介导性心房颤动(房颤)和6h快速起搏介导的房颤模型中研究心房动作电位时限(APD)的回复性质.方法 18只犬随机分为迷走神经介导性房颤组(A组,n=8)和6h快速起搏介导性房颤组(B组,n=10).两组犬麻醉后开胸,暴露心脏,分别在多个肺静脉及心房部位记录单相APD.以APD复极90％(APD90)的时间为纵坐标、以其前的舒张间期为横坐标构建不同部位的APD回复曲线.结果在A组,迷走神经刺激显著缩短每一部位的APD90、使回复曲线变平坦(斜率＜1)并抑制APD交替的发生,但同时迷走神经刺激增加房颤的诱发性和持续时间[(13±3)s对(5±1)s,P＜0.05].在B组,6h快速起搏缩短APD、使回复曲线变陡峭(斜率＞1)并促进APD交替的发生,同时房颤的发生率和持续时间增加[(10±3)s对(5±1)s,P＜0.05].结论迷走神经介导性房颤和6h快速起搏介导的房颤具有不同的回复性质,提示不同机制的房颤具有不同的心房回复性质.
목적 재미주신경개도성심방전동(방전)화6h쾌속기박개도적방전모형중연구심방동작전위시한(APD)적회복성질.방법 18지견수궤분위미주신경개도성방전조(A조,n=8)화6h쾌속기박개도성방전조(B조,n=10).량조견마취후개흉,폭로심장,분별재다개폐정맥급심방부위기록단상APD.이APD복겁90％(APD90)적시간위종좌표、이기전적서장간기위횡좌표구건불동부위적APD회복곡선.결과 재A조,미주신경자격현저축단매일부위적APD90、사회복곡선변평탄(사솔＜1)병억제APD교체적발생,단동시미주신경자격증가방전적유발성화지속시간[(13±3)s대(5±1)s,P＜0.05].재B조,6h쾌속기박축단APD、사회복곡선변두초(사솔＞1)병촉진APD교체적발생,동시방전적발생솔화지속시간증가[(10±3)s대(5±1)s,P＜0.05].결론 미주신경개도성방전화6h쾌속기박개도적방전구유불동적회복성질,제시불동궤제적방전구유불동적심방회복성질.
Objective This study sought to investigate the artrial action potential duration(APD) restitution properties in two different atrial fibrillation(AF) models:vagally mediated AF and 6 h rapid atrial-pacing-induced AF.Methods Eighteen anaesthetized open-chest dogs were assigned in Group A,vagally mediated AF (n=8) or Group B,6 h rapid atrial-pacing-induced AF (n =10).In both groups,the monophasic action potential was subsequently recorded at multiple pulmonary vein and atrial sites.The APD restitution curve was constructed using a dynamic pacing protocol and determined by plotting each APD90 against the preceding diastolic interval at incremental atrial pacing rates at eight sites.Results In Group A,vagal stimulation significantly shortened the APD90,flattened the APD restitution curve (slopes＜1),and suppressed the APD alternans at each site,while increasing the AF inducibility and duration (P＜0.05 for all).In Group B,6 h rapidpacing-induced APD shortening,steepened the restitution curves (slopes＞1),facilitated the APD alternans,and also increased the incidence and duration of AF (P＜0.05 for all).Conclusion This study showed distinct atrial APD restitution properties in vagally mediated AF and 6 h rapid-pacing-induced AF,indicating specific restitution kinetics in different mechanisms of AF.