Studies Made by Simulating Systole at Necropsy. V. Estimation of the Contour of the Left Ventricular Ejection Curve by an Adjusted Integration of the Aortic Blood Pressure Curve

1954 ◽  
Vol 7 (3) ◽  
pp. 273-278 ◽  
Author(s):  
Isaac Starr ◽  
Truman G. Schnabel
Keyword(s):  
Blood Pressure ◽  
Left Ventricular ◽  
Ventricular Ejection ◽  
Left Ventricular Ejection ◽  
Pressure Curve ◽  
Aortic Blood ◽  
Aortic Blood Pressure

Abstract 17298: Validation of Beat-to-Beat Blood Pressure and Left Ventricular Ejection Time by the Caretaker Physiological Monitor Against Invasive Central Aortic Measurement

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Evan Harmon ◽  
Younghoon Kwon ◽  
Patrick Stafford ◽  
Martin Baruch ◽  
Sung-Hoon Kim ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Unmet Need ◽  
Aortic Pressure ◽  
Left Ventricular ◽  
Ventricular Ejection ◽  
Left Ventricular Ejection ◽  
Ejection Time ◽  
Left Ventricular Ejection Time ◽  
Monitoring Technologies ◽  
Ventricular Ejection Time

Objective: There is an unmet need for noninvasive continuous blood pressure (BP) monitoring technologies in various clinical settings. We examined the accuracy of noninvasive Caretaker device against invasively measured central aortic BP. Methods: Beat-to-beat BP by Caretaker was recorded simultaneously with central aortic BP measured in patients undergoing cardiac catheterization. We derived correlations and Bland-Altman comparisons, after calibrating the Caretaker with 20 seconds of the initial catheter readings, as well as trend analyses for both systolic (SBP) and diastolic BP (DBP). We also measured left ventricular ejection time (LVET) from both aortic pressure tracing and Caretaker and compared the two. Results: A total of 47 patients were included in the study. A total of 31,369 beats obtained during the diagnostic portion of coronary angiogram were used for analysis. The correlations for SBP and DBP were 0.89 and 0.78, respectively (p < 0.001 for both). The Bland-Altman comparison yielded overall mean differences of 2.11 mmHg (SD 7.40) for SBP and 1.46 mmHg (SD 6.12) for DBP respectively (p <0.001 for all comparisons). The trend analysis yielded concordances of 86% and 85% for SBP and DBP, respectively. The correlation and Bland-Altman analyses for the LVET comparison yielded 0.89 (p< 0.001) with a mean difference of 13.9 ms (SD 14.4 ms). Conclusion: Beat-to-beat BP by Caretaker showed excellent agreement and high concordance in the direction and the degree of BP change with central aortic BP. This study supports the satisfactory performance of the Caretaker device in continuous tracking of beat-to-beat BP and LVET measurements.

Cardiovascular actions of beta-phenylethylamine

1979 ◽  
Vol 236 (4) ◽  
pp. H592-H595
Author(s):  
C. S. Liang ◽  
D. Sprecher
Keyword(s):  
Blood Pressure ◽  
Vascular Resistance ◽  
Left Ventricular ◽  
Peripheral Vascular Resistance ◽  
Adrenergic Nerve ◽  
Peripheral Vascular ◽  
Vascular Effects ◽  
Aortic Blood ◽  
Total Peripheral Vascular Resistance ◽  
Aortic Blood Pressure

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.

Development of bioimpedance sensing device for wearable monitoring of the aortic blood pressure curve

2018 ◽  
Vol 85 (5) ◽  
pp. 366-377 ◽  
Author(s):  
H. Kõiv ◽  
M. Rist ◽  
M. Min
Keyword(s):  
Blood Pressure ◽  
Blood Vessel ◽  
Axillary Artery ◽  
Vital Signs ◽  
Assessment Method ◽  
Pressure Curve ◽  
Aortic Blood ◽  
Vessel Volume ◽  
Aortic Blood Pressure

Abstract Wearable devices that monitor our vital signs have been gaining more importance with each year. Non-invasive, continuous, accurate and precise blood pressure assessment method integrated in a wearable is a multidisciplinary challenge. This work presents an electrical bioimpedance (EBI) unit for multi-frequency measurements on pulsating artery for central aortic pressure (CAP) estimation. The developed device provides low complexity in the electronics design with a frequency range between 1 kHz and 200 kHz. It is able to register the impedance of blood vessel volume change simultaneously at different locations. Experiments were carried out in vivo by using the four-electrode configuration on human thorax, axillary artery and radial artery. Preliminary results show the applicability of the proposed impedance spectroscopy system to measure blood vessel volume changes. The impedance data can be later interpreted into the aortic blood pressure wave by using a generalized transfer function. In addition, experimental test-phantom and electrode design are introduced for testing purposes of the impedance system.

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 ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Augmentation Index ◽  
Arterial Compliance ◽  
Ventricular Outflow Tract ◽  
Left Ventricular ◽  
Aortic Blood Flow ◽  
Aortic Blood ◽  
Reservoir Function ◽  
Aortic Blood Pressure ◽  
Aortic Reservoir Function

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.

Ascending aortic blood pressure-derived indices are not correlated with the extent of coronary artery disease in patients with impaired left ventricular function

2006 ◽  
Vol 184 (2) ◽  
pp. 370-376 ◽  
Author(s):  
Piotr Jankowski ◽  
Kalina Kawecka-Jaszcz ◽  
Danuta Czarnecka ◽  
Małgorzata Brzozowska-Kiszka ◽  
Aneta Pośnik-Urbańska ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Left Ventricular Function ◽  
Ventricular Function ◽  
Left Ventricular ◽  
Impaired Left Ventricular Function ◽  
Aortic Blood ◽  
Aortic Blood Pressure ◽  
Artery Disease

scholarly journals Sauna exposure leads to improved arterial compliance: Findings from a non-randomised experimental study

2017 ◽  
Vol 25 (2) ◽  
pp. 130-138 ◽  
Author(s):  
Earric Lee ◽  
Tanjaniina Laukkanen ◽  
Setor K Kunutsor ◽  
Hassan Khan ◽  
Peter Willeit ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Mean Arterial Pressure ◽  
Pulse Wave ◽  
Left Ventricular ◽  
Ventricular Ejection ◽  
Left Ventricular Ejection ◽  
Ejection Time ◽  
Left Ventricular Ejection Time ◽  
Sauna Bathing ◽  
Ventricular Ejection Time

Background Heat therapy has been suggested to improve cardiovascular function. However, the effects of hot sauna exposure on arterial compliance and the dynamics of blood flow and pressure have not been well documented. Thus, we investigated the short-term effects of sauna bathing on arterial stiffness and haemodynamics. Design The design was an experimental non-randomised study. Methods There were 102 asymptomatic participants (mean age, 51.9 years) who had at least one cardiovascular risk factor. Participants were exposed to a single sauna session (duration: 30 min; temperature: 73℃; humidity: 10–20%). Pulse wave velocity, augmentation index, heart rate, blood pressure, mean arterial pressure, pulse pressure, augmented pressure and left ventricular ejection time were assessed before, immediately after, and 30 min after a single sauna session. Results Sauna bathing led to reductions in pulse wave velocity, blood pressure, mean arterial pressure and left ventricular ejection time. Mean pulse wave velocity value before sauna was 9.8 m/s and decreased to 8.6 m/s immediately after sauna bathing ( p < 0.001 for difference), and was 9.0 m/s after the 30-minute recovery period ( p < 0.001 for analysis of variance). Systolic blood pressure was 137 mm Hg before sauna bathing, decreasing to 130 mm Hg after sauna ( p < 0.001), which remained sustained during the 30-minute recovery phase ( p < 0.001 for analysis of variance). After a single sauna session, diastolic blood pressure decreased from 82 to 75 mm Hg, mean arterial pressure from 99.4 to 93.6 mm Hg and left ventricular ejection time from 307 to 278 m/s ( p < 0.001 for all differences). Pulse pressure was 42.7 mm Hg before the sauna, 44.9 mm Hg immediately after the sauna, and reduced to 39.3 mm Hg after 30-minutes recovery ( p < 0.001 for analysis of variance). Heart rate increased from 65 to 81 beats/min post-sauna ( p < 0.001); there were no significant changes for augmented pressure and pulse pressure amplification. Conclusion This study shows that pulse wave velocity, systolic blood pressure, diastolic blood pressure, mean arterial pressure, left ventricular ejection time and diastolic time decreased immediately after a 30-minute sauna session. Decreases in systolic blood pressure and left ventricular ejection time were sustained during the 30-minute recovery phase.

Redistribution of Regional Blood Flow after Administration of Saralasin in Salt-Depleted Dogs

1978 ◽  
Vol 55 (s4) ◽  
pp. 243s-246s
Author(s):  
Chang-Seng Liang ◽  
Haralambos Gavras ◽  
H. R. Brunner
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Regional Blood Flow ◽  
Partial Agonist ◽  
Left Ventricular ◽  
Control Group ◽  
Arterial Blood ◽  
Aortic Blood ◽  
Salt Depletion ◽  
Aortic Blood Pressure

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.

Sign in / Sign up

Export Citation Format

Share Document