Effect of increased preload on the synthesized aortic blood pressure waveform

2010 ◽  
Vol 109 (2) ◽  
pp. 484-490 ◽  
Author(s):  
Kevin S. Heffernan ◽  
James E. Sharman ◽  
Eun Sun Yoon ◽  
Eui Jin Kim ◽  
Su Jin Jung ◽  
...  

In the present study, we examined the influence of preload augmentation via passive leg elevation (PLE) on synthesized aortic blood pressure, aortic augmentation index (AIx), and aortic capacitance (a reflection of aortic reservoir function). Central and peripheral hemodynamics were measured via tonometry with a generalized transfer function in 14 young, healthy men (age = 24 yr). Aortic blood flow was calculated from the left ventricular outflow tract (LVOT) velocity-time integral (VTI) using standard two-dimensional echocardiographic-Doppler techniques. Measures were made in the supine position at rest (Pre), during PLE, and during recovery (Post). There was a significant increase in LVOT-VTI, synthesized aortic systolic blood pressure (BP) and AIx from Pre to PLE, with values returning to baseline Post ( P < 0.05). There was a reduction in aortic capacitance from Pre to PLE, with values returning to baseline Post ( P < 0.05). There was no change in heart rate, systemic arterial compliance, aortic elastance, aortic wave travel timing, or vascular resistance ( P > 0.05). Change in AIx from Pre to PLE was associated with change in LVOT-VTI ( r = 0.66, P < 0.05) and inversely associated with change in aortic capacitance ( r = −0.73, P < 0.05). These data suggest that in a setting of isolated augmented preload with minimal changes in other potential confounders, the morphology of the synthesized aortic BP waveform and AIx may be related to changes in aortic reservoir function.

2018 ◽  
Vol 41 (7) ◽  
pp. 378-384 ◽  
Author(s):  
Alper Erdan ◽  
Abdullah Ozkok ◽  
Nadir Alpay ◽  
Vakur Akkaya ◽  
Alaattin Yildiz

Background: Arterial stiffness is a strong predictor of mortality in hemodialysis patients. In this study, we aimed to investigate possible relations of arterial stiffness with volume status determined by bioimpedance analysis and aortic blood pressure parameters. Also, effects of a single hemodialysis session on these parameters were studied. Methods: A total of 75 hemodialysis patients (M/F: 43/32; mean age: 53 ± 17) were enrolled. Carotid-femoral pulse wave velocity, augmentation index, and aortic pulse pressure were measured by applanation tonometry before and after hemodialysis. Extracellular fluid and total body fluid volumes were determined by bioimpedance analysis. Results: Carotid-femoral pulse wave velocity (9.30 ± 3.30 vs 7.59 ± 2.66 m/s, p < 0.001), augmentation index (24.52 ± 9.42 vs 20.28 ± 10.19, p < 0.001), and aortic pulse pressure (38 ± 14 vs 29 ± 8 mmHg, p < 0.001) significantly decreased after hemodialysis. Pre-dialysis carotid-femoral pulse wave velocity was associated with age (r2 = 0.15, p = 0.01), total cholesterol (r2 = 0.06, p = 0.02), peripheral mean blood pressure (r2 = 0.10, p = 0.005), aortic-mean blood pressure (r2 = 0.06, p = 0.02), aortic pulse pressure (r2 = 0.14, p = 0.001), and extracellular fluid/total body fluid (r2 = 0.30, p < 0.0001). Pre-dialysis augmentation index was associated with total cholesterol (r2 = 0.06, p = 0,02), aortic-mean blood pressure (r2 = 0.16, p < 0.001), and aortic pulse pressure (r2 = 0.22, p < 0.001). Δcarotid-femoral pulse wave velocity was associated with Δaortic-mean blood pressure (r2 = 0.06, p = 0.02) and inversely correlated with baseline carotid-femoral pulse wave velocity (r2 = 0.29, p < 0.001). Pre-dialysis Δaugmentation index was significantly associated with Δaortic-mean blood pressure (r2 = 0.09, p = 0.009) and Δaortic pulse pressure (r2 = 0.06, p = 0.03) and inversely associated with baseline augmentation index (r2 = 0.14, p = 0.001). In multiple linear regression analysis (adjusted R2 = 0.46, p < 0.001) to determine the factors predicting Log carotid-femoral pulse wave velocity, extracellular fluid/total body fluid and peripheral mean blood pressure significantly predicted Log carotid-femoral pulse wave velocity (p = 0.001 and p = 0.006, respectively). Conclusion: Carotid-femoral pulse wave velocity, augmentation index, and aortic pulse pressure significantly decreased after hemodialysis. Arterial stiffness was associated with both peripheral and aortic blood pressure. Furthermore, reduction in arterial stiffness parameters was related to reduction in aortic blood pressure. Pre-dialysis carotid-femoral pulse wave velocity was associated with volume status determined by bioimpedance analysis. Volume control may improve not only the aortic blood pressure measurements but also arterial stiffness in hemodialysis patients.


1979 ◽  
Vol 236 (4) ◽  
pp. H592-H595
Author(s):  
C. S. Liang ◽  
D. Sprecher

beta-Phenylethylamine increased mean aortic blood pressure, total peripheral vascular resistance, left ventricular dP/dt, and (dP/dt)/P in chloralose-anesthetized dogs. Pretreatment with phentolamine reduced the increases in aortic blood pressure and total peripheral vascular resistance produced by beta-phenylethylamine, whereas, the effects of beta-phenylethylamine on left ventricular dP/dt and (dP/dt)/P were abolished by propranolol. beta-Phenylethylamine pretreatment, but increased both after phentolamine pretreatment. Furthermore, both the cardiac and vascular effects of beta-phenylethylamine were abolished by desipramine. These results indicate that beta-phenylethylamine exerts both positive inotropic and vasoconstrictory effects, probably by releasing endogenous norepinephrine from the adrenergic nerve endings.


Author(s):  
S. A. Mironova ◽  
Yu. S. Yudina ◽  
M. A. Ionov ◽  
N. G. Avdonina ◽  
I. V. Emelyanov ◽  
...  

Aim. To compare the relationships between conventional and new potentially more early investigational biomarkers (urine and ultrasound) of kidney injury and central aortic blood pressure, vascular stiffness and reactivity, endothelial dysfunction in patients with different severity of hypertension.Material and methods. Urine levels NGAL, KIM-1, L-FABP, albuminuria and serum levels of сystatin C and creatinine were measured in 92 hypertensive patients with mild and severe hypertension, 46 male (mean age 50,7±12,2 years). Glomerular filtration rate was estimated by the level of serum creatinine and cystatin C by MDRD and CKD-EPI formulas. Instrumental examination included measuring office blood pressure, 24-hour ambulatory blood pressure monitoring (SpaceLabs 90207), applanation tonometry (SphygmoCor, Artcor Medical) with the calculation of central aortic blood pressure, pulse wave velocity and augmentation index and Doppler ultrasonography with assessment of intraparenchymal renal arterial resistance indices — resistive index and pulsatility index (Vivid 7 dimension). Endothelial function was assessed by reactive hyperemia index with EndoPAT device (Itamar Medicals).Results. There were no differences in conventional levels of biomarkers between patients, however, cystatin C level increased and serum cystatin C estimated GFR and serum creatinine and cystatin C estimated GFR (CKD EPI formula) (sCr,Cys-estimated GFR) levels decreased with the severity of hypertension. These novel biomarkers were associated with increased central aortic blood pressure, arterial stiffness and intraparenchymal renal arterial resistance indices. Decreased sCr,Cys-estimated GFR levels were associated with lower reactive hyperemia index. There were no differences in NGAL, KIM-1 and L-FABP levels in patients with hypertension. However, NGAL levels were associated with increased augmentation index, resistive index in intralobular and pulsatility index in arcuate arteries, KIM-1 and L-FABP levels were associated with increased systolic and diastolic central aortic blood pressure, pulse wave velocity only in patients with severe and resistant hypertension.Conclusion. Serum cystatin C, NGAL, KIM-1 and L-FABP levels seem to be biomarkers of increased systemic and intrarenal vascular stiffness in patients with different severity of hypertension.


1978 ◽  
Vol 55 (s4) ◽  
pp. 243s-246s
Author(s):  
Chang-Seng Liang ◽  
Haralambos Gavras ◽  
H. R. Brunner

1. Salt depletion was produced in five dogs by a low salt diet and daily administration of frusemide for 5 days; a control group of five dogs was placed on the same diet, to which 2·5 g of sodium chloride was added. 2. Saralasin infusion (0·5 μg min−1 kg−1) reduced mean aortic blood pressure and total peripheral vascular resistance and increased cardiac output in salt-depleted dogs, but did not affect the heart rate and left ventricular dP/dt. 3. Saralasin infusion increased mean aortic blood pressure slightly in normal dogs; other systemic haemodynamic parameters did not change significantly. 4. Saralasin decreased hepatic arterial flow in both normal and salt-depleted dogs, but increased blood flow to left ventricle and kidneys only in salt-depleted dogs. 5. These results suggest that saralasin exerts a partial agonist effect in normal dogs to increase arterial blood pressure, but causes a depressor response during salt depletion because it reverses the vasoconstrictor effect of angiotensin II, particularly on the renal and coronary circulations.


2010 ◽  
Vol 28 (11) ◽  
pp. 2252-2257 ◽  
Author(s):  
Gion Ruegg ◽  
Rebecca H Mason ◽  
Maxine Hardinge ◽  
Jeremy Perkins ◽  
Marc Husmann ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document