TY - JOUR

T1 - Factors related to end-systolic volume are important determinants of peak early diastolic transmitral flow velocity

AU - Courtois, M.

AU - Mechem, C. J.

AU - Barzilai, B.

AU - Ludbrook, P. A.

PY - 1992

Y1 - 1992

N2 - Background. Three important determinants of left ventricular (LV) peak early diastolic filling rate, which is related directly to the magnitude of the transmitral pressure difference, are the rate of LV isovolumic pressure fall (T( 1/2 )), left atrial (LA) pressure at mitral valve opening (X1), and end-systolic volume (ESV). Methods and Results. To delineate the relative degrees to which these factors contribute to the magnitude of peak early diastolic filling rate, we measured LA and regional intra-LV pressures with micromanometers, LV volume with contrast angiography, and peak transmitral flow velocity (E) with transesophageal Doppler echocardiography in 16 anesthetized closed-chest dogs. E did not correlate significantly with either X1 (r=-0.255) or T( 1/2 ) (r=-0.281). Multivariate analysis, with E entered as the dependent variable and X1 and T( 1/2 ) as independent variables, also failed to reach significance (R=0.310). E correlated significantly with ESV (r=-0.633, p<0.009). Using multivariate analysis, the major determinants of ESV were found to be LV contractility (+dP/dt), afterload (aortic diastolic pressure, Ao(dias)), and preload (end-diastolic volume, EDV) (R=0.848, p<0.001). E correlated significantly with two of the determinants of ESV (+dP/dt and Ao(dias)) (R=0.906, p<0.001); however, the addition of EDV did not significantly improve the multivariate relation (R=0.911). To determine whether X1 or T( 1/2 ) would add significantly to the above multivariate relation, these factors were entered individually along with +dP/dt and Ao(dias) as third independent variables. Neither the addition of X1 (R=0.906) or T( 1/2 ) (R=0.926) resulted in a significant improvement in the prediction of E. Conclusions. Our observations confirm the importance of factors related to ESV as important determinants of early diastolic filling. These relations suggest that the process of early diastolic function is intimately related to systolic function.

AB - Background. Three important determinants of left ventricular (LV) peak early diastolic filling rate, which is related directly to the magnitude of the transmitral pressure difference, are the rate of LV isovolumic pressure fall (T( 1/2 )), left atrial (LA) pressure at mitral valve opening (X1), and end-systolic volume (ESV). Methods and Results. To delineate the relative degrees to which these factors contribute to the magnitude of peak early diastolic filling rate, we measured LA and regional intra-LV pressures with micromanometers, LV volume with contrast angiography, and peak transmitral flow velocity (E) with transesophageal Doppler echocardiography in 16 anesthetized closed-chest dogs. E did not correlate significantly with either X1 (r=-0.255) or T( 1/2 ) (r=-0.281). Multivariate analysis, with E entered as the dependent variable and X1 and T( 1/2 ) as independent variables, also failed to reach significance (R=0.310). E correlated significantly with ESV (r=-0.633, p<0.009). Using multivariate analysis, the major determinants of ESV were found to be LV contractility (+dP/dt), afterload (aortic diastolic pressure, Ao(dias)), and preload (end-diastolic volume, EDV) (R=0.848, p<0.001). E correlated significantly with two of the determinants of ESV (+dP/dt and Ao(dias)) (R=0.906, p<0.001); however, the addition of EDV did not significantly improve the multivariate relation (R=0.911). To determine whether X1 or T( 1/2 ) would add significantly to the above multivariate relation, these factors were entered individually along with +dP/dt and Ao(dias) as third independent variables. Neither the addition of X1 (R=0.906) or T( 1/2 ) (R=0.926) resulted in a significant improvement in the prediction of E. Conclusions. Our observations confirm the importance of factors related to ESV as important determinants of early diastolic filling. These relations suggest that the process of early diastolic function is intimately related to systolic function.

KW - Doppler

KW - diastole

KW - echocardiography

KW - echocardiography

KW - pressure gradients

KW - transesophageal

KW - ventricle

UR - http://www.scopus.com/inward/record.url?scp=0026564550&partnerID=8YFLogxK

U2 - 10.1161/01.CIR.85.3.1132

DO - 10.1161/01.CIR.85.3.1132

M3 - Article

C2 - 1537111

AN - SCOPUS:0026564550

SN - 0009-7322

VL - 85

SP - 1132

EP - 1138

JO - Circulation

JF - Circulation

IS - 3

ER -