Morphological observation on the left ventricle of canine heart.

Objective To observe and measure the anatomical structures of the left ventricle in canis familiaris,in order to accumulate data for comparative anatomy.Methods Forty-five hearts of canis familiaris were fixed with 1.44 mol·L-1 formaldehyde,then the structure of the left ventricle were observed and measured.Results The left ventricle of canine heart was a cone and was located in left of the heart.It was divided into inflowing tract and outflow tract of left ventricle.The main structures of the inflowing tract were mitral complex,which was composed of the mitral ring and valve,chordae tendineae and papillary muscles.The average length of mitral ring was(49.16±10.00)mm,the heights of inside and outside valves were(14.28±3.14) and(9.27±1.99)mm respectively,the breadths of them were(25.74±5.21) and(21.50±6.33)mm respectively.The average number of chordae tendineae and falese tendon was 16.72±2.76 and 4.69±3.38.The frequency of false tendon was 100%.The main structures of the outflow tract of left ventricle were aortic orifice,aortic valve and aortic sinus.The average length of aortic orifice was(34.55±8.00)mm,the heights of left,right and back aortic valve were(6.85±1.76),(7.19±1.75) and(7.52±1.79)mm respectively,the breadths of them were(11.47±3.02),(11.67±2.99) and(11.74±2.46)mm respectively.Conclusion The left ventricle of canis familiaris is similar to that of human heart in structure,but there was difference in size and the total number of chordae tendineae and false tendon.