Total arterial compliance estimated by stroke volume-to-aortic pulse pressure ratio in humans.
On the basis of the windkessel model, the stroke volume-to-aortic pulse pressure ratio (SV/PP) has been proposed as an estimate of total arterial compliance, but recent studies have questioned this approximation. Aortic pressure was obtained at rest in 31 adults undergoing cardiac catheterization (47 +/- 14 yr): controls (n = 7), patients with dilated cardiomyopathy (n = 10), and patients with other cardiac diseases (n = 14). We calculated PP, mean aortic pressure (MAoP), heart period (T), SV (thermodilution cardiac output/heart rate), total peripheral resistance (R), total arterial compliance estimated by area method (Carea), and the time constant of aortic pressure decay in diastole (RCarea). In the overall population (n = 31), there was no significant difference between SV/PP and Carea. SV/PP was linearly related to Carea (SV/PP = 0.99Carea + 0.05; r = 0.98; P < 0.001); the slope and intercept did not differ from unity and zero, respectively. Similar results were obtained in the three subgroups. These results implied that PP/MAoP and T/RCarea were proportionally related (T/RCarea = 1.18PP/MAoP - 0.07; r = 0.96; P < 0.001). We conclude that for humans at rest 1) SV/PP gave a reliable estimate of Carea, and 2) T normalized by the time constant of aortic pressure decay in diastole was proportionally related to PP/MAoP. This last relationship could be considered an aspect of the coupling between the left ventricle and its load.
Chemla
D
D
Institut National de la Santé et de la Recherche Médicale, U451-Loa-Ensta-Ecole Polytechnique, Palaiseau, France.
Hébert
J L
JL
Coirault
C
C
Zamani
K
K
Suard
I
I
Colin
P
P
Lecarpentier
Y
Y
D000328:Adult; D000368:Aged; D001011:Aorta / Q000502:physiology*; D001794:Blood Pressure; D006328:Cardiac Catheterization; D002311:Cardiomyopathy, Dilated / Q000503:physiopathology; D005260:Female; D006331:Heart Diseases / Q000503:physiopathology; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011673:Pulsatile Flow; D012680:Sensitivity and Specificity; D013318:Stroke Volume