[Properties of arteries, cardiac function and structure in chronic hypertension].
Hypertension is a condition which demonstrates the relationship between the properties of the left ventricle and arterial system. The spectrum of aortic impedence expresses the principal factors which oppose LV ejection into the initial aorta: 1) capacitive forces related to the viscoelastic properties of the arterial wall, directly proportional to its rigidity, 2) forces of inertia which increase with the acceleration of the blood and which are inversely proportional to the aortic cross sectional area, 3) reflection. With respect to a stroke volume which is usually normal, hypertension is characterised by: 1) an increase in mean aortic pressure (MAP), 2) with respect to the increase in MAP, an increase in systolic, late systolic and differential pressures. These changes in the level and morphology of aortic pressure are due to: a) the increase in systemic arterial resistances, a continuous expression of the spectrum of the module, b) an increase in the elastic forces (increased rigidity of the aorta related to increased pressure and structural wall changes) usually insufficiently compensated by a decrease in the inertial forces (aortic dilatation), c) an earlier return of the reflected pulse wave, well before the end of the anterograde wave. Overall, there is a relationship between the mass, the geometry (concentric hypertrophy) and pump function of the left ventricle and the properties of the arterial system expressed in terms of pulse wave velocity, characteristic impedence or the late systolic pressure/stroke volume ratio. The relationship is much closer than that of the properties of the LV and aortic pressure.(ABSTRACT TRUNCATED AT 250 WORDS)
Paillole
C
C
Service de cardiologie, hôpital Bichat, Paris.
Lerallut
J F
JF
Mérillon
J P
JP
Dahan
M
M
Cohen-Solal
A
A
Himbert
D
D
Gourgon
R
R
D000375:Aging; D001158:Arteries / Q000503:physiopathology*; D001783:Blood Flow Velocity; D002908:Chronic Disease; D004548:Elasticity; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D009200:Myocardial Contraction; D011673:Pulsatile Flow; D013318:Stroke Volume; D014655:Vascular Resistance; D016277:Ventricular Function, Left
Propriétés du système artériel, fonction et structure cardiaques dans l'hypertension artérielle permanente.