Validity of estimated aortic pulse wave velocity measured during the 6-min walk test to predict anaerobic fitness before major non-cardiac surgery.

Background: This study aimed to assess the efficacy of estimated preoperative aortic pulse wave velocity (AoPWV) to discriminate between low and high 6 min walk test (6MWT) distance in patients awaiting major non-cardiac surgery.

Methods: Prospective observational study in 133 patients undergoing non cardiac surgery. AoPWV and the distance walked during a 6MWT were assessed.

The role of pulse wave analysis indexes for critically ill patients: a narrative review.

Arterial pulse wave analysis (PWA) is now established as a powerful tool to investigate the cardiovascular system, and several clinical studies have shown how PWA can provide valuable prognostic information over and beyond traditional cardiovascular risk factors. Typically these techniques are applied to chronic conditions, such as hypertension or aging, to monitor the slow structural changes of the vascular system which lead to important alterations of the arterial PW. However, their application to acute critical illness is not currently widespread, probably because of the high hemodynamic instability and acute dynamic alterations affecting the cardiovascular system of these patients.

Haemodynamic effects of labetalol in isoflurane-anaesthetized dogs that received dexmedetomidine: A randomized clinical trial.

Objective: To test whether labetalol improved cardiovascular function in anaesthetized dogs injected with dexmedetomidine.

Study Design: Prospective, randomized, blinded, clinical trial.

Animals: A group of 20 healthy client-owned dogs undergoing ovariohysterectomy.

Longitudinal Validation of Right Ventricular Pressure Monitoring for the Assessment of Right Ventricular Systolic Dysfunction in a Large Animal Ischemic Model.

Unlabelled: Right ventricular (RV) dysfunction is a major cause of morbidity and mortality in intensive care and cardiac surgery. Early detection of RV dysfunction may be facilitated by continuous monitoring of RV waveform obtained from a pulmonary artery catheter. The objective is to evaluate the extent to which RV pressure monitoring can detect changes in RV systolic performance assess by RV end-systolic elastance (E) following the development of an acute RV ischemic in a porcine model.

Pharmacodynamic analysis of a fluid challenge with 4 ml kg over 10 or 20 min: a multicenter cross-over randomized clinical trial.

Purpose: A number of studies performed in the operating room evaluated the hemodynamic effects of the fluid challenge (FC), solely considering the effect before and after the infusion. Few studies have investigated the pharmacodynamic effect of the FC on hemodynamic flow and pressure variables. We designed this trial aiming at describing the pharmacodynamic profile of two different FC infusion times, of a fixed dose of 4 ml kg.

COVID-19-related echocardiographic patterns of cardiovascular dysfunction in critically ill patients: A systematic review of the current literature.

Purpose: Coronavirus disease 2019 (COVID-19) infection may trigger a multi-systemic disease involving different organs. There has been growing interest regarding the harmful effects of COVID-19 on the cardiovascular system. This systematic review aims to systematically analyze papers reporting echocardiographic findings in hospitalized COVID-19 subjects.

Mini fluid chAllenge aNd End-expiratory occlusion test to assess flUid responsiVEness in the opeRating room (MANEUVER study): A multicentre cohort study.

Background: The fluid challenge response in surgical patients can be predicted by functional haemodynamic tests. Two tests, the mini-fluid challenge (mini-FC) and end-expiratory occlusion test (EEOT), have been assessed in a few small single-centre studies with conflicting results. In general, functional haemodynamic tests have not performed reliably in predicting fluid responsiveness in patients undergoing laparotomy.

Dynamic Arterial Elastance During Experimental Endotoxic Septic Shock: A Potential Marker of Cardiovascular Efficiency.

Dynamic arterial elastance (Ea), the ratio between pulse pressure variation (PPV) and stroke volume variation (SVV), has been suggested as a dynamic parameter relating pressure and flow. We aimed to determine the effects of endotoxic septic shock and hemodynamic resuscitation on Ea in an experimental study in 18 New Zealand rabbits. Animals received placebo (SHAM, = 6) or intravenous lipopolysaccharide (E.

Understanding ventriculo-arterial coupling.

In the late 19th century, Otto Frank published the first description of a ventricular pressure-volume diagram, thus laid the foundation for modern cardiovascular physiology. Since then, the analysis of the pressure-volume loops became a reference tool for the study of the ventricular pump properties. However, understanding cardiovascular performance requires both the evaluation of ventricular properties and the modulating effects of the arterial system, since the heart and the arterial tree are anatomically and functionally related structures.

Dynamic Arterial Elastance as a Ventriculo-Arterial Coupling Index: An Experimental Animal Study.

Dynamic arterial elastance (Ea), the ratio between arterial pulse pressure and stroke volume changes during respiration, has been postulated as an index of the coupling between the left ventricle (LV) and the arterial system. We aimed to confirm this hypothesis using the gold-standard for defining LV contractility, afterload, and evaluating ventricular-arterial (VA) coupling and LV efficiency during different loading and contractile experimental conditions. Twelve Yorkshire healthy female pigs submitted to three consecutive stages with two opposite interventions each: changes in afterload (phenylephrine/nitroprusside), preload (bleeding/fluid bolus), and contractility (esmolol/dobutamine).

Increased atrial contraction contribution to left ventricular filling during early septic shock.

Purpose: To assess the atrial systolic function and the contribution of atrial contraction to left ventricular (LV) filling in septic shock patients as compared with healthy volunteers.

Methods: Twenty-seven septic patients evaluated during first 48 h of ICU admission and compared with 27 healthy volunteers. Left atrial (LA) contraction contribution to LV filling was calculated as the active emptying atrial volume/LV end-diastolic volume.

Determinants of left ventricular ejection fraction and a novel method to improve its assessment of myocardial contractility.

Background: The aim of this study was to quantify the impact of different cardiovascular factors on left ventricular ejection fraction (LVEF) and test a novel LVEF calculation considering these factors.

Results: 10 pigs were studied. The experimental protocol consisted of sequentially changing afterload, preload and contractility.

Reliability of effective arterial elastance using peripheral arterial pressure as surrogate for left ventricular end-systolic pressure.

To compare the effective arterial elastance (Ea) obtained from the arterial pressure with Ea calculated from left-ventricular (LV) pressure-volume analysis. Experimental study. LV pressure-volume data was obtained with a conductance catheter and arterial pressures were measured via a fluid-filled catheter placed in the proximal aorta, femoral and radial arteries.

Performance comparison of ventricular and arterial dP/dt for assessing left ventricular systolic function during different experimental loading and contractile conditions.

Background: Maximal left ventricular (LV) pressure rise (LV dP/dt), a classical marker of LV systolic function, requires LV catheterization, thus surrogate arterial pressure waveform measures have been proposed. We compared LV and arterial (femoral and radial) dP/dt to the slope of the LV end-systolic pressure-volume relationship (Ees), a load-independent measure of LV contractility, to determine the interactions between dP/dt and Ees as loading and LV contractility varied.

Methods: We measured LV pressure-volume data using a conductance catheter and femoral and radial arterial pressures using a fluid-filled catheter in 10 anesthetized pigs.