[Model of the normal left ventricle].
The aim of the present study is to simulate left ventricular function using parametres directly measurable "in vivo". Taking the definition of contractility as sigma EDV/ESV (sigma = end systolic stress; EDV = end diastolic volume; ESV = end systolic volume), a slight modification of Suga's index, and an equation taken from Sunagawa, relating arterial pressure to resistance, compliance and stroke volume, a basic programme able to predict stroke volume and systolic pressure starting from EDV, left ventricular mass, contractility, peripheral resistance and compliance was developed. Various curves describing left ventricular function were simulated: Starling's curve, pump curve (mean left ventricular pressure against mean left ventricular flow), Ford's curve (mass to volume ratio against systemic pressure), and pressure-volume loops. A close affinity with literature data was always found. Left ventricular performances were predicted in 23 normal subjects, using the same input parameters. The correlation with real values was always linear, and particularly striking for cardiac index and source resistance. Thus this model seems to explain low-frequency hemodynamic events adequately, and is therefore suitable of clinical use in order to clarify pathophysiological mechanisms.
Razzolini
R
R
Università degli Studi di Padova, Istituto di Medicina Clinica, Cattedra di Cardiologia.
Boffa
G M
GM
Stritoni
P
P
Chioin
R
R
Villanova
C
C
Volta
S D
SD
D006321:Heart / Q000502:physiology*; D006439:Hemodynamics; D006801:Humans; D008954:Models, Biological; D009200:Myocardial Contraction; D013318:Stroke Volume
Simulazione del ventricolo sinistro normale.