[Structure of the cardiac systole in mammals and birds].
The comparative analysis of the contractile function of the heart left ventricle in four species of homoeothermic tetrapods (chicken, quail, rat, sheep) who differ in their spatio-temporal pattern of ventricular excitation, heart rate, and heart weight was performed. The analysis of cardiac cycle structure was performed on the basis of synchronous recording of ECG, phonocardiogram, and apex cardiogram. Indices of myocardial contractility of the left ventricle calculated on the basis of the analysis of the cardiac dynamics indicate disadvantageous contractile function of the left ventricle in rodents and non-flying birds in comparison with sheep. The functioning of the left ventricle in male rats is more strained than in female rats. One fundamental factor determining a more strained functioning of the left ventricle in birds in comparison with mammals is the heart rate. The relative weight and activation pattern of the left ventricular myocardium govern the contractile function of the left ventricle to a lesser extent.
S N
SN
Kharin
D N
DN
Shmakov
V V
VV
Krandycheva
V A
VA
Vitiazev
D000818:Animals; D002645:Chickens / Q000502:physiology*; D005260:Female; D006321:Heart / Q000502:physiology*; D008297:Male; D009929:Organ Size / Q000502:physiology; D011784:Quail / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012727:Sex Characteristics; D012756:Sheep / Q000502:physiology*; D013045:Species Specificity; D013599:Systole / Q000502:physiology*; D016277:Ventricular Function, Left / Q000502:physiology