Vol. 45, No. 2, 2001
THE EFFECTS OF MYOCARDIAL INFARCTION ON THE KINETICS OF THE MITRAL VALVE AND PRE-EJECTION AND EJECTION TIME IN DOGS
Department of Internal Medicine
Faculty Oof Veterinary Medicine
Istanbul University
Avcılar - Istanbul
TURKEY
Summary
The purpose of the this study was to determine (1) whether dogs with myocardial infarction introduced experimentally have any changes in the kinetics of the mitral valve and the pre-ejection (PET) and ejection time (ET) of the left ventricle, and (2) whether the pre-ejection time provided a new index for ventricular function.
Fourteen healthy mongrel dogs (9 females and 5 males) were used. The dogs were divided in two groups; a control group (n = 7) and the experimental group (n = 7). At the beginning of the study, E-A and D-C intervals from the mitral valve (MV), and PET and ET of the left ventricle from the aortic valve were measured by motion mode (M-mode) echocardiography in all the dogs. The distal left descending coronary artery was ligated in the experimental group under a general anaesthesia. The same parameters were measured at the 2nd, 4nd, 8th, and 12th hours and repeated for seven days.
At 4 and 12 hours after the coronary ligation, a decrease in E-A and D-C intervals were seen (p = ns). Vibrations were also seen on anterior cusp of the mitral valve and the aortic valve. The pre-ejection time decreased between 2nd and 8th hours post ligation, then, E-A and D-C intervals increased. ET and PET were not statistically significant. No change in the ejection time was present after ligation.
The present study demonstrates that the E-A and D-C intervals of the mitral valve, and the pre-ejection and ejection time of left ventricle do not undergo any significant changes, although kinetic disorders of mitral valve occur in dogs with myocardial infarction.
Key words: dog; ejection time; left ventricle; myocardial infarction; pre-ejection time
References
Folia Veterinaria / 2001