Action potential duration restitution and the potential association with ventricular arrhythmia in Langendorff-perfused chronic heart failure rabbit hearts
10.3760/cma.j.issn.0253-3758.2012.06.003
- VernacularTitle:慢性心力衰竭兔离体心室电整复性变化对室性心律失常的影响
- Author:
Tao LIU
1
;
Mu QIN
;
Zhen CHEN
;
He HU
;
He HUANG
;
Cong-Xin HUANG
Author Information
1. 武汉大学
- Keywords:
Heart failure,congestive;
Arrhythmia;
Isoproterenol;
Action potentials
- From:
Chinese Journal of Cardiology
2012;40(6):467-472
- CountryChina
- Language:Chinese
-
Abstract:
Objective To observe the action potential duration restitution (APDR) change and potential association with ventricular arrhythmia (VA) in Langendorff-perfused chronic heart failure rabbit hearts.Methods Male rabbits were randomly divided into two groups:control ( CTL,n =15 ) group and chronic heart failure (CHF,n =15) group.CHF was induced by injecting isoproterenol (300 μg · kg-1 ·d -1 ) for 14 days.Four weeks later,cardiac function and structure change of both groups were assessed by echocardiography.In the whole Langendorff-perfused hearts,the monophasic action potential (MAP) and the effective refractory period (ERP) were recorded from left anterior basal ventricle,left anterior free wall,left anterior apex and left posterior basal ventricle,left posterior free wall and left posterior apex,the APD curves were also constructed in both groups:at the six sites of every isolated heart,the programmed electrical stimulation and burst pacing were used to induce action potential duration (APD) alternans and VA,respectively.Results Left ventricular ejection was reduced and end-dimension was enlarged in rabbits of CHF group.Compared with the same sites of CTL group,the 90％ of MAP duration ( MAPD90 ),the ERP,the max slope ( Smax ) of APDR curves,the pacing cycle length of inducing the APD alternans and the VAs were significantly increased ( all P ＜ 0.05 ) in CHF group:the spatial dispersions of MAPD90,E RP and Smax of APDR curves in CHF group were also greater than in CTL group ( all P ＜0.05 ).Conclusion The ventricular APD alternans might be linked with occurrence of the VA in CHF rabbits.Increase of the Smax from APDR curves and the spatial dispersions of Smax in this CHF model might facilitate the development of ventricular arrhythmia.
