中文摘要：

目的研究增龄对犬心房和肺静脉电生理学特性影响。方法17只杂种犬按年龄分为两组，成年犬7只，老年犬10只，做12导联同步心电图，测量P波平均时限和P波离散度；放置冠状静脉窦电极，左、右心耳电极，左上、左下、右上、右下肺静脉电极，测量各部位有效不应期（ERP）、ERP离散度及频率适应性。结果与成年犬相比，老年犬的P波平均时限延长，P波离散度增大；右心耳和冠状静脉窦近端ERP延长，左心耳和冠状静脉窦远端以及左上肺静脉ERP缩短；心房各部位及肺静脉ERP离散度增大；左心耳和冠状静脉窦远端及左上肺静脉频率适应性减低。结论增龄对心房和肺静脉电生理影响主要是左心房和左上肺静脉ERP缩短和频率适应性减低，心房及肺静脉ERP离散度增大。

英文摘要：

Objective To investigate the changes in atrium and pulmonary veins with aging. Methods Seventeen canines were allocated to two groups, seven adult canines and ten old canines. Basic data were col- lected before operation,include 12-lead surface electrocardiography （ECG） and echocardiography. P wave aver- age duration （PAD） and P wave dispersion（PWD） were measured on 12-lead ECGs. Muhipolar catheters were placed at the coronary sinus（ CS）, left and right atrial appendages （LAA and RAA） , left and right superior pulmonary veins （ LSPV and RSPV） ,left and right inferior pulmonary veins （ LIPV and R1PV）. Electrophysio- logical index were measured, including effective refractory period （ERP） , rate adaptability, dispersion of ERP （ERPd）. Results Compared with the adult group, PAD was prolonged and PWD was increased in aged group; the ERP of RAA and proximal CS （CSp） were prolonged, the ERP of LAA and distal CS（CSd） were short- ened. ERPd at all sites of atrium and pulmonary veins were increased;the rate adaptabilities of ERP at LAA, CSd and LSPV were decreased. Conclusion Aging is a normal physiological process, it alters the electrophysi- ological features of the atrium and pulmonary vein,including the shortening of ERP at left atrium and LSPV and maladaptation, as well as increasing of ERPd at all sites of atrium and pulmonary veins.