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The Journal of Invasive Cardiology Nov 2017Although the terms ventricularization and damping are commonly used in the cath lab and are widely recognized as indicating possible flow limitation due to catheter... (Review)
Review
Although the terms ventricularization and damping are commonly used in the cath lab and are widely recognized as indicating possible flow limitation due to catheter position, their hemodynamic origins and mechanism have not been well studied. Often, they are thought to be synonymous terms. Both patterns are due to distortion of the normal harmonic frequencies of wave conduction. Pressure damping is seen when the outer diameter of the catheter is larger than the ostial diameter or when the tip of the catheter is pressed against the vessel wall. It is characterized by an abrupt decline of mean coronary pressure with narrow pulse pressure and delayed upstroke and downstroke. Conversely, ventricularization is seen when the catheter tip is advanced into an ostial stenosis, partially obstructing flow, and is characterized by a steep decline of pressure in diastole with large pulse pressure, absence of the dicrotic notch, and appearance of presystolic positive deflection. A ventricularized pressure waveform can be considered a hybrid between coronary arterial pressure and coronary wedge pressure.
Topics: Blood Pressure; Cardiac Catheterization; Coronary Circulation; Coronary Vessels; Humans
PubMed: 29086728
DOI: No ID Found -
Current Opinion in Critical Care Jun 2018In the field of prediction of fluid responsiveness, the most recent studies have focused on validating new tests, on clarifying the limitations of older ones, and better... (Review)
Review
PURPOSE OF REVIEW
In the field of prediction of fluid responsiveness, the most recent studies have focused on validating new tests, on clarifying the limitations of older ones, and better defining their modalities.
RECENT FINDINGS
The limitations of pulse pressure/stroke volume variations are numerous, but recent efforts have been made to overcome these limitations, like in case of low tidal volume ventilation. Following pulse pressure/stroke volume variations, new tests have emerged which assess preload responsiveness by challenging cardiac preload through heart-lung interactions, like during recruitment manoeuvres and end-expiratory/inspiratory occlusions. Given the risk of fluid overload that is inherent to the 'classical' fluid challenge, a 'mini' fluid challenge, made of 100 ml of fluid only, has been developed and investigated in recent studies. The reliability of the passive leg raising test is now well established and the newest publications have mainly aimed at defining several noninvasive estimates of cardiac output that can be monitored to assess its effects.
SUMMARY
Research in this field is still very active, such that several indices and tests of fluid responsiveness are now available. They may contribute to reduce excessive fluid balance by avoiding unnecessary fluid administration and, also, by ensuring safe fluid removal.
Topics: Adult; Aged; Aged, 80 and over; Blood Pressure; Cardiac Output; Female; Fluid Therapy; Hemodynamic Monitoring; Hemodynamics; Humans; Male; Middle Aged; Reproducibility of Results; Stroke Volume
PubMed: 29634494
DOI: 10.1097/MCC.0000000000000501 -
European Journal of Preventive... Mar 2018
Topics: Blood Pressure; Blood Pressure Determination; Humans; Pressure; Risk
PubMed: 29372648
DOI: 10.1177/2047487318755805 -
JMIR Public Health and Surveillance Jul 2023The causal relationship between blood pressure variability (BPV) and arterial stiffness remains debated.
BACKGROUND
The causal relationship between blood pressure variability (BPV) and arterial stiffness remains debated.
OBJECTIVE
This study aimed to explore the temporal and bidirectional associations between long-term BPV and arterial stiffness using a cohort design with multiple surveys.
METHODS
Participants from the Beijing Health Management Cohort who underwent health examinations from visit 1 (2010-2011) to visit 5 (2018-2019) were enrolled in this study. Long-term BPV was defined as intraindividual variation using the coefficient of variation (CV) and SD. Arterial stiffness was measured by brachial-ankle pulse wave velocity (baPWV). The bidirectional relationship between BPV and arterial stiffness was explored using cross-lagged analysis and linear regression models, with records before and after visit 3 categorized as phase 1 and phase 2, respectively.
RESULTS
Of the 1506 participants, who were a mean of 56.11 (SD 8.57) years old, 1148 (76.2%) were male. The cross-lagged analysis indicated that the standardized coefficients of BPV at phase 1 directing to the baPWV level at phase 2 were statistically significant but not vice-versa. The adjusted regression coefficients of the CV were 4.708 (95% CI 0.946-8.470) for systolic blood pressure, 3.119 (95% 0.166-6.073) for diastolic pressure, and 2.205 (95% CI 0.300-4.110) for pulse pressure. The coefficients of the SD were 4.208 (95% CI 0.177-8.239) for diastolic pressure and 4.247 (95% CI 0.448-8.046) for pulse pressure. The associations were predominant in the subgroup with hypertension, but we did not observe any significant association of baPWV level with subsequent BPV indices.
CONCLUSIONS
The findings supported a temporal relationship between long-term BPV and arterial stiffness level, especially among people with hypertension.
Topics: Humans; Male; Child; Female; Blood Pressure; Ankle Brachial Index; Cohort Studies; Vascular Stiffness; Pulse Wave Analysis; Hypertension
PubMed: 37402142
DOI: 10.2196/45324 -
JAMA Jun 2020
Topics: Blood Pressure; Humans; Hypertension; Systole
PubMed: 32543680
DOI: 10.1001/jama.2020.5937 -
Journal of the American College of... Feb 2016
Topics: Atherosclerosis; Blood Pressure; Female; Humans; Male; Registries; Risk Assessment; Thrombosis
PubMed: 26821628
DOI: 10.1016/j.jacc.2015.11.022 -
JAMA Jun 2020
Topics: Blood Pressure; Blood Pressure Determination; Humans; Hypertension
PubMed: 32543678
DOI: 10.1001/jama.2020.5931 -
Acta Neurochirurgica. Supplement 2021The slope of linear relationship between the amplitude of pulsations in intracranial pressure (ICP) versus mean ICP has recently been suggested as a useful guide for...
The slope of linear relationship between the amplitude of pulsations in intracranial pressure (ICP) versus mean ICP has recently been suggested as a useful guide for selecting patients for shunt surgery in normal pressure hydrocephalus (NPH). To better understand how the pathophysiology of cerebral circulation influences this parameter, we aimed to study the relationship between mean pressure and pulsation amplitude in a wide range of conditions affecting cerebrovascular tone and ICP in experimental conditions.We retrospectively analysed experimental material collected previously. Three physiological manoeuvres were studied in 29 New Zealand white rabbits: lumbar infusion with an infusion rate ≤0.2 mL/min to induce mild intracranial hypertension (n = 43), sympathetic blockade to induce arterial hypotension (n = 19), and modulation of the ventilator tidal volume, simultaneously influencing arterial carbon dioxide partial pressure (PaCO) to induce hypocapnia or hypercapnia (n = 17). We investigated whether the slope of the pulse amplitude (AMP)-ICP line depended on PaCO and arterial blood pressure (ABP) changes.We found a linear correlation between AMP-ICP and ICP with positive slope. Regression of slope against mean ABP showed a negative dependence (p = 0.03). In contrast, the relationship between slope and PaCO was positive, although not reaching statistical significance (p = 0.18).The slope of amplitude-pressure line is strongly modulated by systemic vascular variables and therefore should be taken as a descriptor of cerebrospinal fluid dynamics with great care.
Topics: Animals; Blood Pressure; Cerebrovascular Circulation; Hydrocephalus, Normal Pressure; Intracranial Hypertension; Intracranial Pressure; Rabbits; Retrospective Studies
PubMed: 33839858
DOI: 10.1007/978-3-030-59436-7_52 -
European Journal of Heart Failure Nov 2016
Topics: Arteries; Blood Pressure; Heart Failure; Humans; Ventricular Dysfunction, Left
PubMed: 27647807
DOI: 10.1002/ejhf.650 -
American Journal of Hypertension May 2023There are six different formulae for estimating mean arterial pressure (MAP) from systolic and diastolic pressure readings. This study is to determine the optimum...
BACKGROUND
There are six different formulae for estimating mean arterial pressure (MAP) from systolic and diastolic pressure readings. This study is to determine the optimum formula for calculating MAP when compared to the gold standard approach, which is the area under the curve of an invasively measured pulse waveform divided by the cardiac cycle duration.
METHODS
Eight live pigs were used as the experimental model for the invasive measurement of femoral artery pressure (AP) by a fluid filled catheter connected with a pressure transducer. In addition, intraocular pressure (IOP) and jugular vein pressure (JVP) were also recorded. The mean pressure (MP) was calculated from digital waveforms sampled at 1,000 points per second with the six formulae and area method for AP, IOP and JVP.
RESULTS
The absolute mean difference between the area MAP and each formula's MAP ranged from 0.98 to 3.23 mm Hg. Our study also found that even under physiological conditions, area MAP can vary between successive pulses by up to 5 mm Hg. For mean IOP and JVP, the mean difference between a formula's MP and the area method's was less than 1 mm Hg for most formulae. With the pooled data, there was excellent agreement amongst all formulae for MAP with the intra-class correlation coefficient (ICC) ranging from 0.97 to 0.99, while the ICC of most formulae for IOP and JVP was 1.0.
CONCLUSIONS
Our study suggests that all current formulae are adequate for estimating MAP, though some formulae are not suitable for mean IOP and JVP.
Topics: Swine; Animals; Blood Pressure; Intraocular Pressure; Arterial Pressure; Heart; Heart Rate
PubMed: 36945835
DOI: 10.1093/ajh/hpad026