Heart-lung interactions during positive pressure ventilation: left ventricular pressure-volume momentary response to airway pressure elevation

Continuous airway pressure delivered by a head-box is an accepted means of treating clinical hyaline membrane disease. To investigate hemodynamic alterations resulting from its use, eight newborn lambs, 1 to 6 days of age, were studied at 6 and 11 mm Hg of positive pressure, while spontaneously breathing room air. Organ blood flows and cardiac output were measured with 25 µ-diameter radioactive microspheres. Heart rate, left ventricular pressure, and arterial blood gases did not change during the study. Jugular venous pressures increased from 6.4 mm Hg to 18.6 and 24.2 mm Hg at 6 and 11 mm Hg, respectively (P < .005). Cardiac output decreased approximately 20% at either intrachamber pressure setting. Renal blood flow fell 21% at 11 mm Hg. No significant changes in blood flow were found in the brain, gastrointestinal tract, spleen, heart, or liver when compared to control flows. Of particular interest was the finding of a 28% reduction in ocular blood flow at 6 mm Hg and 52% at 11 mm Hg. From these results, we conclude that substantial cardiovascular alterations may occur during the application of head-box continuous airway pressure breathing, including a significant reduction in ocular blood flow.

Download Full-text

Endothelin Receptor Blockade Improves Left Ventricular Pressure-Volume Relationships Without Altering the Hypertrophic Response During Congestive Heart Failure in Rats

Journal of the American College of Cardiology ◽

10.1016/s0735-1097(97)84967-4 ◽

1998 ◽

Vol 31 (2) ◽

pp. 289A

Author(s):

E Øie

Keyword(s):

Heart Failure ◽

Congestive Heart Failure ◽

Left Ventricular Pressure ◽

Left Ventricular ◽

Ventricular Pressure ◽

Receptor Blockade ◽

Endothelin Receptor ◽

Hypertrophic Response

Download Full-text

Oxygenation failure after cardiac operations: early re-intubation versus treatment by nasal continuous positive airway pressure (nCPAP) or non-invasive positive pressure ventilation (NPPV)

The Thoracic and Cardiovascular Surgeon ◽

10.1055/s-2006-925712 ◽

2006 ◽

Vol 54 (S 1) ◽

Author(s):

U Boeken ◽

P Feindt ◽

J Litmathe ◽

M Kurt ◽

E Gams

Keyword(s):

Continuous Positive Airway Pressure ◽

Airway Pressure ◽

Positive Pressure Ventilation ◽

Positive Airway Pressure ◽

Positive Pressure ◽

Non Invasive ◽

Versus Treatment ◽

Cardiac Operations

Download Full-text

Faculty Opinions recommendation of The relative contribution of prosthetic gradients, systemic arterial pressure, and pulse pressure to the left ventricular pressure in patients with aortic prosthetic valves.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.9881957.10592055 ◽

2011 ◽

Author(s):

Olav F Münter Sellevold

Keyword(s):

Arterial Pressure ◽

Pulse Pressure ◽

Left Ventricular Pressure ◽

Systemic Arterial Pressure ◽

Left Ventricular ◽

Ventricular Pressure ◽

Relative Contribution ◽

Prosthetic Valves

Download Full-text

Beat-to-Beat Analysis of Left Ventricular Pressure-Volume Relation and Stroke Volume by Conductance Catheter and Aortic Modelflow in Cardiomyoplasty Patients

Circulation ◽

10.1161/01.cir.91.7.2010 ◽

1995 ◽

Vol 91 (7) ◽

pp. 2010-2017 ◽

Cited By ~ 57

Author(s):

J.J. Schreuder ◽

F.H. van der Veen ◽

E.T. van der Velde ◽

F. Delahaye ◽

O. Alfieri ◽

...

Keyword(s):

Stroke Volume ◽

Left Ventricular Pressure ◽

Left Ventricular ◽

Ventricular Pressure ◽

Conductance Catheter ◽

Volume Relation

Download Full-text

Contribution of extravascular compression to reduction of maximal coronary blood flow

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1992.262.1.h68 ◽

1992 ◽

Vol 262 (1) ◽

pp. H68-H77

Author(s):

F. L. Abel ◽

R. R. Zhao ◽

R. F. Bond

Keyword(s):

Blood Flow ◽

Coronary Blood Flow ◽

Coronary Flow ◽

Perfusion Pressure ◽

Left Ventricular Pressure ◽

Coronary Perfusion Pressure ◽

Left Ventricular ◽

Ventricular Pressure ◽

Coronary Perfusion ◽

Storage Site

Effects of ventricular compression on maximally dilated left circumflex coronary blood flow were investigated in seven mongrel dogs under pentobarbital anesthesia. The left circumflex artery was perfused with the animals' own blood at a constant pressure (63 mmHg) while left ventricular pressure was experimentally altered. Adenosine was infused to produce maximal vasodilation, verified by the hyperemic response to coronary occlusion. Alterations of peak left ventricular pressure from 50 to 250 mmHg resulted in a linear decrease in total circumflex flow of 1.10 ml.min-1 x 100 g heart wt-1 for each 10 mmHg of peak ventricular to coronary perfusion pressure gradient; a 2.6% decrease from control levels. Similar slopes were obtained for systolic and diastolic flows as for total mean flow, implying equal compressive forces in systole as in diastole. Increases in left ventricular end-diastolic pressure accounted for 29% of the flow changes associated with an increase in peak ventricular pressure. Doubling circumferential wall tension had a minimal effect on total circumflex flow. When the slopes were extrapolated to zero, assuming linearity, a peak left ventricular pressure of 385 mmHg greater than coronary perfusion pressure would be required to reduce coronary flow to zero. The experiments were repeated in five additional animals but at different perfusion pressures from 40 to 160 mmHg. Higher perfusion pressures gave similar results but with even less effect of ventricular pressure on coronary flow or coronary conductance. These results argue for an active storage site for systolic arterial flow in the dilated coronary system.

Download Full-text

Nasal Intermittent Positive Pressure Ventilation versus Continuous Positive Airway Pressure and Apnea of Prematurity: A Systematic Review and Meta-Analysis

American Journal of Perinatology ◽

10.1055/s-0040-1722337 ◽

2021 ◽

Author(s):

Bayane Sabsabi ◽

Ava Harrison ◽

Laura Banfield ◽

Amit Mukerji

Keyword(s):

Systematic Review ◽

Continuous Positive Airway Pressure ◽

Airway Pressure ◽

Primary Outcome ◽

Positive Pressure Ventilation ◽

Positive Airway Pressure ◽

Meta Analysis ◽

Intermittent Positive Pressure Ventilation ◽

Positive Pressure ◽

Apnea Of Prematurity

Objective The study aimed to systematically review and analyze the impact of nasal intermittent positive pressure ventilation (NIPPV) versus continuous positive airway pressure (CPAP) on apnea of prematurity (AOP) in preterm neonates. Study Design In this systematic review and meta-analysis, experimental studies enrolling preterm infants comparing NIPPV (synchronized, nonsynchronized, and bi-level) and CPAP (all types) were searched in multiple databases and screened for the assessment of AOP. Primary outcome was AOP frequency per hour (as defined by authors of included studies). Results Out of 4,980 articles identified, 18 studies were included with eight studies contributing to the primary outcome. All studies had a high risk of bias, with significant heterogeneity in definition and measurement of AOP. There was no difference in AOPs per hour between NIPPV versus CPAP (weighted mean difference = −0.19; 95% confidence interval [CI]: −0.76 to 0.37; eight studies, 456 patients). However, in a post hoc analysis evaluating the presence of any AOP (over varying time periods), the pooled odds ratio (OR) was lower with NIPPV (OR: 0.46; 95% CI: 0.32–0.67; 10 studies, 872 patients). Conclusion NIPPV was not associated with decrease in AOP frequency, although demonstrated lower odds of developing any AOP. However, definite recommendations cannot be made based on the quality of the published evidence. Key Points

Download Full-text

The crosstalk of HDAC3, microRNA-18a and ADRB3 in the progression of heart failure

Cell & Bioscience ◽

10.1186/s13578-020-00523-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jingtao Na ◽

Haifeng Jin ◽

Xin Wang ◽

Kan Huang ◽

Shuang Sun ◽

...

Keyword(s):

Heart Failure ◽

Expression Patterns ◽

Systolic Pressure ◽

Left Ventricular Pressure ◽

Left Ventricular ◽

Ventricular Pressure ◽

Luciferase Reporter ◽

Left Ventricular Ejection ◽

Tunel Staining ◽

Ventricular Ejection Fraction

Abstract Background Heart failure (HF) is a clinical syndrome characterized by left ventricular dysfunction or elevated intracardiac pressures. Research supports that microRNAs (miRs) participate in HF by regulating targeted genes. Hence, the current study set out to study the role of HDAC3-medaited miR-18a in HF by targeting ADRB3. Methods Firstly, HF mouse models were established by ligation of the left coronary artery at the lower edge of the left atrial appendage, and HF cell models were generated in the cardiomyocytes, followed by ectopic expression and silencing experiments. Numerous parameters including left ventricular posterior wall dimension (LVPWD), interventricular septal dimension (IVSD), left ventricular end diastolic diameter (LVEDD), left ventricular end systolic diameter (LVESD), left ventricular ejection fraction (LVEF), left ventricular fractional shortening (LVFS), left ventricular systolic pressure (LVSP), left ventricular end diastolic pressure (LEVDP), heart rate (HR), left ventricular pressure rise rate (+ dp/dt) and left ventricular pressure drop rate (-dp/dt) were measured in the mice. In addition, apoptosis in the mice was detected by means of TUNEL staining, while RT-qPCR and Western blot analysis were performed to detect miR-18a, HDAC3, ADRB3, cMyb, MMP-9, Collagen 1 and TGF-β1 expression patterns. Dual luciferase reporter assay validated the targeting relationship between ADRB3 and miR-18a. Cardiomyocyte apoptosis was determined by means of flow cytometry. Results HDAC3 and ADRB3 were up-regulated and miR-18a was down-regulated in HF mice and cardiomyocytes. In addition, HDAC3 could reduce the miR-18a expression, and ADRB3 was negatively-targeted by miR-18a. After down-regulation of HDAC3 or ADRB3 or over-expression of miR-18a, IVSD, LVEDD, LVESD and LEVDP were found to be decreased but LVPWD, LVEF, LVFS, LVSP, + dp/dt, and −dp/dt were all increased in the HF mice, whereas fibrosis, hypertrophy and apoptosis of HF cardiomyocytes were declined. Conclusion Collectively, our findings indicate that HDAC3 silencing confers protection against HF by inhibiting miR-18a-targeted ADRB3.

Download Full-text