Increase In Cardiac Index Research Articles

Mitral regurgitation evolution after transcatheter tricuspid valve interventions; a sub-analysis of the TriValve registry.

Abstract Background Transcatheter tricuspid valve interventions(TTVI) are increasingly used to treat patients with significant tricuspid regurgitation(TR).[1] The evolution of concurrent mitral regurgitation(MR) severity after TTVI is currently unknown. Increasing severity of TR is associated with declining cardiac output, while a significant increase in left ventricular preload and cardiac index have been observed in patients undergoing successful tricuspid valve surgery with functional improvement.[2,3] Physiological studies, instead, have demonstrated MR worsening in response to preload augmentation especially in the setting of left ventricular systolic disfunction; however, it is unknown whether increased left ventricular preload might translate into clinically relevant MR worsening after successful TTVI.[2,4] Gaining insights regarding the trajectories of MR severity after TTVI may significantly contribute to clinical decision-making. Indeed, it would help to define whether patients undergoing TTVI may benefit from a concurrent transcatheter procedure on the mitral valve. Purpose The aim of this study was to assess the evolution of MR after TTVI and to identify predictors of MR worsening and improvement. Methods This analysis is a substudy of the Trivalve Registry, an international registry designed to collect data on TTVI.[5] This substudy included all patients with echocardiographic data on MR evolution and excluded those with a concomitant tricuspid and mitral transcatheter valve intervention or with a history of mitral valve intervention. The co-primary outcomes were MR improvement and worsening at two timepoints: pre-discharge and 2-month follow-up. Results The graphical abstract is presented in Figure 1. This analysis included 359 patients with severe TR, mostly(80%) treated with tricuspid transcatheter edge-to-edge repair(T-TEER). MR improvement was found in 106(29.5%) and 99(27%) patients, while MR worsening in 34(9.5%) and 33(9%) patients at pre-discharge and 2-month follow-up, respectively. The type of transcatheter procedure has a significant impact on MR worsening and improvement. Annuloplasty and heterotopic replacement were associated with MR worsening. Independent positive predictors of MR improvement were T-TEER, acute procedural success, TR reduction, LVEDD>60 mm and beta-blocker therapy while atrial fibrillation was a negative predictor. Patients with moderate-to-severe/severe MR following TTVI showed significantly higher death rates while the stratification according to MR evolution was not prognostically relevant(Figure 2). Conclusions MR degree variation is common after TTVI, with most cases showing improvement. Clinical and procedural characteristics may predict the MR evolution, in particular procedural success and T-TEER play key roles in MR outcomes. An effective TTVI with significant TR reduction may prevent MR worsening and possibly trigger an improvement, differently from the common belief. Figure 1. Graphical abstract. Figure 2. Death rates.

Comparison of clinical results between transpulmonary thermodilution monitoring and conventional methods in cardiac surgery: An observational study.

The Pulse Index Contour Continuous Cardiac Output (PICCO) module provides advanced and continuous monitoring of cardiac output through the use of arterial pulse contour analysis and transpulmonary thermodilution. The objective of this study was to compare the early postoperative outcomes of patients who were monitored using the conventional method and the pulse contour analysis method. A prospective observational study was conducted involving 45 patients who underwent cardiac surgery between 2020 and 2022. Patients were randomly assigned to either Group P (PICCO) or Group C (conventional). In the PICCO cohort, a femoral artery cannula was inserted for the continuous recording and management of hemodynamic data, in accordance with the decision-making algorithm of the module. In the conventional group, cannulation of the radial artery and jugular vein was performed. The postoperative hemodynamic and clinical data are subjected to analysis. The utilization of dopamine was markedly diminished in Group P at both the 0- and 6-hour postoperative intervals, whereas the administration of dobutamine was observed to be elevated (P = .008). The frequency of red packed cell transfusions was higher in Group C at postoperative hour 0. Hemodynamic data indicated a 42% increase in cardiac index and a 33% decrease in systemic vascular resistance, along with a 33% increase in global ejection fraction in patients monitored with PICCO. The mortality rates observed in the 2 groups were not statistically different. The implementation of advanced monitoring techniques, specifically the PICCO module, led to notable enhancements in hemodynamic parameters. The utilization of this technique may prove advantageous in guiding inotrope selection and transfusion decisions during the initial postoperative period. However, it is important to note that morbidity and mortality rates remain comparable.

Mitral Valve Transcatheter Edge-to-Edge Repair (MV-TEER) in Patients with Secondary Mitral Regurgitation Improves Hemodynamics, Enhances Renal Function, and Optimizes Quality of Life in Patients with Advanced Renal Insufficiency.

Secondary mitral regurgitation (MR) is a common valvular heart disease burdening the prognosis of patients with co-existing chronic heart failure. Transcatheter edge-to-edge mitral valve repair (MV-TEER) is a minimally invasive treatment option for high-risk patients. However, the effects of MV-TEER on expanded hemodynamics, tissue perfusion, and quality of life, particularly in patients with advanced renal failure, remain underexplored. This prospective, single-center study evaluated the impact of MV-TEER on hemodynamics, renal function, and quality of life in 45 patients with severe MR. Non-invasive bioimpedance monitoring with NICaS® was used to assess hemodynamics pre- and 3-5 days post-procedure. Quality of life was assessed using the EQ-5D-3L questionnaire before and 3 months post-procedure. For further analysis, patients were divided into subgroups based on the estimated baseline glomerular filtration rate (eGFR < 35 mL/min vs. eGFR ≥ 35 mL/min). A significant reduction in systemic vascular resistance (SVR; p = 0.003) and an increase in eGFR (p = 0.03) were observed in the entire cohort after MV-TEER, indicating improved tissue perfusion. Notably, particularly patients with eGFR < 35 mL/min showed a significant increase in cardiac output (CO; p = 0.035), cardiac index (CI; p = 0.031), and eGFR (p = 0.018), as well as a reduction in SVR (p = 0.007). Consistent with these findings, quality of life significantly improved, with the EQ-5D-3L index and EQ-VAS score increasing from 0.44 to 0.66 (p < 0.001) and from 51.7% to 62.9% (p < 0.001).

A Network Meta-Analysis of Vasodilator Therapies in Pulmonary Hypertension Patients Undergoing Mitral Valve Replacement Surgery: Insights for Optimizing Hemodynamics.

Pulmonary hypertension (PH) is a progressive hemodynamic condition associated with significant morbidity and mortality, especially in patients undergoing cardiac surgery. Therefore, the objective of this network meta-analysis (NMA) is to compare the efficacy of various pulmonary vasodilators in perioperative control of PH among patients undergoing mitral valve replacement surgery (MVRS), aiming to address the existing knowledge gap and improve perioperative outcomes. Electronic databases including PubMed, Cochrane Central Registry of Controlled Trials, Scopus, Embase, and Web of Science (WOS) from inception to 17 September 2024. Only randomized controlled trials (RCTs) evaluating vasodilators in PH patients undergoing MVRS were included. We used netmeta package in RStudio to analyze the outcome data with their corresponding mean difference (MD) and confidence intervals (CI). Seventeen RCTs including 862 patients were analyzed. Prostacyclin, nitric oxide (NO), and sodium nitroprusside (SN) significantly reduced mean pulmonary arterial pressure with effect sizes [MD, 95% confidence interval (CI)] of (11.77, -18.78; -4.76; -8.3, -15.9; -0.6; -11.02, -20.1; -3.8, respectively). While no treatment showed significant efficacy on pulmonary capillary wedge pressure, systolic pulmonary arterial pressure, or heart rate, nitroglycerin, NO, and prostacyclin, showed significant increases in cardiac index with effect sizes (MD, 95% CI) of (1, 0.3; 1.7; 1.2 0.8; 1.6; 1.2 0.8; 1.6, respectively). Additionally, NO, prostacyclin, SN, and nitroglycerin demonstrated significant reductions in systemic vascular resistance (SVR), with effect sizes of. (-0.54, -0.82; -0.26, -0.37, -0.65; -0.09; -0.47, -0.77; -0.16; -0.14, -0.24; -0.03, respectively). This NMA highlights prostacyclin, nitroglycerin, NO, and SN as consistently effective in improving hemodynamics for patients with PH undergoing MVRS, and provides valuable insights for surgeons to choose the suitable vasodilator for these surgeries. However, limitations and the need for further RCTs are acknowledged.

Changes in portal pulsatility index induced by a fluid challenge in patients with haemodynamic instability and systemic venous congestion: a prospective cohort study

BackgroundIt is uncertain whether fluid administration can improve patients with systemic venous congestion and haemodynamic instability. This study aimed to describe the changes in systemic venous congestion and peripheral perfusion parameters induced by a fluid challenge in these patients, and to analyse the influence of the fluid responsiveness status on these changes.MethodsThe study is a single-centre prospective cohort study of 36 critically ill ICU patients with haemodynamic instability and a maximum vena cava diameter ≥ 20 mm. Changes in cardiac index during a fluid challenge (4 mL/kg of lactated Ringer’s solution during 5 min) assessed by pulse contour analysis, central venous pressure, ultrasound systemic congestion parameters (portal venous flow pulsatility index, supra hepatic and intrarenal venous Doppler), and peripheral perfusion parameters (capillary refill time and peripheral perfusion index) were assessed in the overall population. All these data were compared between patients presenting a cardiac index increase > 10% during the fluid challenge (fluid responders) and the others (fluid non-responders).ResultsTwenty-eight (78%) patients were admitted for postoperative care following cardiac surgery; their mean ± SD left ventricular ejection fraction was 42 ± 9% and right ventricular dysfunction was found in at least 61% of the patients. The mean ± SD SOFA score was 9 ± 3. Thirteen (36%) patients were fluid responders. The fluid challenge administration induced a significant increase in portal pulsatility index, VExUS score, and central venous pressure without significant difference of these changes between fluid responders and non-responders. No significant change in perfusion parameters was observed.ConclusionFluid administration in patients with haemodynamic instability and systemic venous congestion worsens venous congestion regardless of the fluid responsiveness status, without improving perfusion parameters.

Testing preload responsiveness by the tidal volume challenge assessed by the photoplethysmographic perfusion index

BackgroundTo detect preload responsiveness in patients ventilated with a tidal volume (Vt) at 6 mL/kg of predicted body weight (PBW), the Vt-challenge consists in increasing Vt from 6 to 8 mL/kg PBW and measuring the increase in pulse pressure variation (PPV). However, this requires an arterial catheter. The perfusion index (PI), which reflects the amplitude of the photoplethysmographic signal, may reflect stroke volume and its respiratory variation (pleth variability index, PVI) may estimate PPV. We assessed whether Vt-challenge-induced changes in PI or PVI could be as reliable as changes in PPV for detecting preload responsiveness defined by a PLR-induced increase in cardiac index (CI) ≥ 10%.MethodsIn critically ill patients ventilated with Vt = 6 mL/kg PBW and no spontaneous breathing, haemodynamic (PICCO2 system) and photoplethysmographic (Masimo-SET technique, sensor placed on the finger or the forehead) data were recorded during a Vt-challenge and a PLR test.ResultsAmong 63 screened patients, 21 (33%) were excluded because of an unstable PI signal and/or atrial fibrillation and 42 were included. During the Vt-challenge in the 16 preload responders, CI decreased by 4.8 ± 2.8% (percent change), PPV increased by 4.4 ± 1.9% (absolute change), PIfinger decreased by 14.5 ± 10.7% (percent change), PVIfinger increased by 1.9 ± 2.6% (absolute change), PIforehead decreased by 18.7 ± 10.9 (percent change) and PVIforehead increased by 1.0 ± 2.5 (absolute change). All these changes were larger than in preload non-responders. The area under the ROC curve (AUROC) for detecting preload responsiveness was 0.97 ± 0.02 for the Vt-challenge-induced changes in CI (percent change), 0.95 ± 0.04 for the Vt-challenge-induced changes in PPV (absolute change), 0.98 ± 0.02 for Vt-challenge-induced changes in PIforehead (percent change) and 0.85 ± 0.05 for Vt-challenge-induced changes in PIfinger (percent change) (p = 0.04 vs. PIforehead). The AUROC for the Vt-challenge-induced changes in PVIforehead and PVIfinger was significantly larger than 0.50, but smaller than the AUROC for the Vt-challenge-induced changes in PPV.ConclusionsIn patients under mechanical ventilation with no spontaneous breathing and/or atrial fibrillation, changes in PI detected during Vt-challenge reliably detected preload responsiveness. The reliability was better when PI was measured on the forehead than on the fingertip. Changes in PVI during the Vt-challenge also detected preload responsiveness, but with lower accuracy.

Central venous oxygen saturation changes as a reliable predictor of the change of CI in septic shock: To explore potential influencing factors

Assessing fluid responsiveness relying on central venous oxygen saturation (ScvO2) yields varied outcomes across several studies. This study aimed to determine the ability of the change in ScvO2 (ΔScvO2) to detect fluid responsiveness in ventilated septic shock patients and potential influencing factors. In this prospective, single-center study, all patients conducted from February 2023 to January 2024 received fluid challenge. Oxygen consumption was measured by indirect calorimetry, and fluid responsiveness was defined as an increase in cardiac index (CI)≥10% measured by transthoracic echocardiography. Multivariate linear regression analysis was conducted to evaluate the impact of oxygen consumption, arterial oxygen saturation, CI, and hemoglobin on ScvO2 and its change before and after fluid challenge. The Shapiro-Wilk test was used for the normality of continuous data. Data comparison between fluid responders and non-responders was conducted using a two-tailed Student t-test, Mann Whitney U test, and Chi-square test. Paired t-tests were used for normally distributed data, while the Wilcoxon signed-rank test was used for skewed data, to compare data before and after fluid challenge. Among 49 patients (31 men, aged (59±18) years), 27 were responders. The patients had an acute physiology and chronic health evaluation II score of 24±8, a sequential organ failure assessment score of 11±4, and a blood lactate level of (3.2±3.1) mmol/L at enrollment. After the fluid challenge, the ΔScvO2 (mmHg) in the responders was greater than that in the non-responders (4±6 vs. 1±3, p=0.019). Multivariate linear regression analysis suggested that CI was the only independent influencing factor of ScvO2, with R2=0.063, p=0.008. After the fluid challenge, the change in CI became the only contributing factor to ΔScvO2 (R2=0.245, p<0.001). ΔScvO2 had a good discriminatory ability for the responders and non-responders with a threshold of 4.4% (area under the curve=0.732, p=0.006). ΔScvO2 served as a reliable surrogate marker for ΔCI and could be utilized to assess fluid responsiveness, given that the change in CI was the sole contributing factor to the ΔScvO2. In stable hemoglobin conditions, the absolute value of ScvO2 could serve as a monitoring indicator for adequate oxygen delivery independent of oxygen consumption.

CO2 gap changes compared with cardiac output changes in response to intravenous volume expansion and/or vasopressor therapy in septic shock.

The difference in partial pressure of carbon dioxide (PCO2) between mixed or central venous blood and arterial blood, known as the ∆PCO2 or CO2 gap, has demonstrated a strong relationship with cardiac index during septic shock resuscitation. Early monitoring of the ∆PCO2 can help assess the cardiac output (CO) adequacy for tissue perfusion. To investigate the value of ∆PCO2 changes in early septic shock management compared with CO. This observational prospective study included 76 patients diagnosed with septic shock admitted to Cairo University Hospital's Critical Care Department between December 2020 and March 2022. Patients were categorised by initial resuscitation response, initial ∆PCO2 and 28-day mortality. The primary outcome was the relationship between the ∆PCO2 and CO changes before and after initial resuscitation, with secondary outcomes including ICU length of stay (LOS) and 28-day mortality. Peri-resuscitation ∆PCO2 changes predicted a ≥15% change in the cardiac index (CI) (area under the curve (AUC) 0.727; 95% CI 0.614 - 0.840) with 66.7% sensitivity and 62.8% specificity. The optimal ∆PCO2 change cut-off value was <-1.85, corresponding to a <-22% threshold for a 15% cardiac index increase. The PCO2 gap ratio (gap/gap ratio of T1- PCO2 gap to T0 -PCO2 gap) also predicted a ≥15% change in cardiac index (AUC 745; 95% CI 0.634 - 0.855) with 63.6% sensitivity and 79.1% specificity. The optimal CO2 gap/gap ratio cut-off value was <0.71. A significant difference in 28-day mortality was noted based on the gap/gap ratio. Peri-resuscitation ∆PCO2 and the gap/gap ratio are useful non-invasive bedside markers for predicting changes in CO and preload responsiveness. The current study provides an insight to the PCO2 gap changes during and after early resuscitation of septic shock patients, which correlate to cardiac output changes and might also serve as a fluid responsiveness indicator.

Prediction of fluid responsiveness for patients in shock using a ventilator disconnection test combined with the pulse contour-derived cardiac index.

Finding a simple and reliable method to predict and assess fluid responsiveness has long been of clinical interest. To investigate the predictive value of a ventilator disconnection (DV) test combined with the pulse contour-derived cardiac output (PiCCO) index on fluid responsiveness for patients in shock. Thirty-two patients were chosen for the study. Patients who were in shock, received mechanical ventilation, and met the inclusion criteria were selected. Patients were divided into a fluid-responsive group (14 patients) and fluid-unresponsive group (18 patients) based on whether the increase in cardiac index (Δ CI) was > 10% or not, respectively, following the fluid challenge test. Changes in heart rate, pulse oximeter-measured oxygen saturation, mean arterial pressure (MAP), and CI before and after passive leg raising (PLR), DV, and fluid challenge tests were observed. We used Pearson's correlation coefficient to analyze an increase in the MAP (Δ MAP) and Δ CI before and after the PLR, DV, and fluid challenge tests; the sensitivity and specificity of the Δ MAP and Δ CI in the PLR and DV tests for predicting fluid response were also analyzed by plotting the receiver operating characteristic (ROC) curves. CI results in the PLR and DV tests, as well as the fluid challenge test, were significantly higher in the fluid-responsive group compared with before the test (P< 0.05). The Δ CI before and after the PLR, DV, and fluid challenge tests were positively correlated among patients in the fluid-responsive group. The area under the ROC curve for the post-PLR test CI and the post-DV CI for predicting fluid responsiveness was 0.869 (95% confidence interval (CI) [0.735-1.000, P= 0.000]) and 0.937 (95% CI [0.829-1.000, P= 0.000]), respectively, in patients in the fluid-responsive group. The sensitivity and specificity of the post-DV CI for predicting fluid responsiveness in all patients was 100.0% and 88.9%, respectively, using a 5% increase as the cut-off value. Application of DV, combined with PiCCO, has a high predictive value for fluid responsiveness among patients in shock.

Cardiogenic Shock Intravascular Cooling Trial (CHILL-SHOCK)

Cardiogenic shock (CS) is complicated by high mortality rates. Targeted temperature control (TTC) has been proposed as an adjunct therapy in CS. This study aims to examine the safety of TTC in patients presenting with CS. In this open-label, randomized controlled pilot trial, 20 patients with hemodynamic criteria for CS were assigned to standard of care plus TTC vs standard of care alone. The primary outcome was a composite safety outcome, including well-described complications of TTC. Secondary outcomes included mortality at 90 days, invasive hemodynamic and echocardiographic parameters, electrocardiographic measurements, and inotrope dosing. There were no significant differences in the composite analysis of prespecified safety outcomes (3 events in the TTC group vs 0 events in the control group; P = 0.24). Patients randomized to TTC demonstrated a statistically significant increase in cardiac index and cardiac power index compared to the control group at 48-96 hours after randomization (3.6 [3.1, 3.9] L/min/m2 vs 2.6 [2.5, 3.15] L/min/m2; P = 0.029 and 0.61 [0.55, 0.7] W/m2 vs 0.53 [0.435, 0.565] W/m2; P = 0.029, respectively). TTC may be a safe adjunct therapy for patients presenting with CS and may yield improvement in specific hemodynamic parameters.

Influence of myocardial contractility therapy for advanced heart failure

With more than 5 million patients’ diagnosed with heart failure (HF) and more than 1 million hospitalizations each year, HF continues to have a significant impact on health-care resources. Despite treatment, a significant number of patients continue to have progressive HF symptoms, classified as Class III or IV. The aim of this study was to compare different inotropic therapy for patients of End-Stage Heart Failure. When persistent intravenous access was used and acute hemodynamic improvement was established, the durable medical equipment (DME) benefit category reimbursed 80% of outpatient inotropic medication and supplies for HF. Acute hemodynamic improvement was defined as a 20% reduction in pulmonary capillary wedge pressure and/or a 20% increase in cardiac index, both of which were related to a decrease in dyspnea. The Centers for Medicaid and Medicare Services contracted with regional carriers to run the program. The amounts reimbursed per beneficiary for inotrope and supplies (not adjusted for differential follow-up) were essentially representative of the inotrope cost. Dobutamine, milrinone, and supplies had mean (and median) amounts of 5025 (1168), 87781 (31440), and 7284 (3131), respectively. We found that patients who received this medication had a relatively high death rate, however not as high as people who received chemotherapy. Milrinone-treated patients were compensated more for hospitalizations both before and after starting the inotrope. In addition, the milrinone group had a higher level of digoxin use in the background. Nonetheless, there is an early decrease in overall expenditures following inotrope initiation, which can be attributed to a decrease in hospitalization. Considering the lack of double-blind trials comparing inotropes to placebo or dobutamine to milrinone, decisions regarding the use of inotropes, the type of inotrope used, and the duration of treatment should take into account the impact on resources.

Discussion of hemodynamic optimization strategies and the canonical understanding of hemodynamics during biventricular mechanical support in cardiogenic shock: does the flow balance make the difference?

BackgroundMechanical circulatory support (MCS) devices may stabilize patients with severe cardiogenic shock (CS) following myocardial infarction (MI). However, the canonical understanding of hemodynamics related to the determination of the native cardiac output (CO) does not explain or support the understanding of combined left and right MCS. To ensure the most optimal therapy control, the current principles of hemodynamic measurements during biventricular support should be re-evaluated.MethodsHere we report a protocol of hemodynamic optimization strategy during biventricular MCS (VA-ECMO and left ventricular Impella) in a case series of 10 consecutive patients with severe cardiogenic shock complicating myocardial infarction. During the protocol, the flow rates of both devices were switched in opposing directions (+ / − 0.7 l/min) for specified times. To address the limitations of existing hemodynamic measurement strategies during biventricular support, different measurement techniques (thermodilution, Fick principle, mixed venous oxygen saturation) were performed by pulmonary artery catheterization. Additionally, Doppler ultrasound was performed to determine the renal resistive index (RRI) as an indicator of renal perfusion.ResultsThe comparison between condition 1 (ECMO flow > Impella flow) and condition 2 (Impella flow > VA-ECMO flow) revealed significant changes in hemodynamics. In detail, compared to condition 1, condition 2 results in a significant increase in cardiac output (3.86 ± 1.11 vs. 5.44 ± 1.13 l/min, p = 0.005) and cardiac index (2.04 ± 0.64 vs. 2.85 ± 0.69, p = 0.013), and mixed venous oxygen saturation (56.44 ± 6.97% vs. 62.02 ± 5.64% p = 0.049), whereas systemic vascular resistance decreased from 1618 ± 337 to 1086 ± 306 s*cm−5 (p = 0.002). Similarly, RRI decreased in condition 2 (0.662 ± 0.05 vs. 0.578 ± 0.06, p = 0.003).ConclusionsTo monitor and optimize MCS in CS, PA catheterization for hemodynamic measurement is applicable. Higher Impella flow is superior to higher VA-ECMO flow resulting in a more profound increase in CO with subsequent improvement of organ perfusion.Graphical

The effect of passive leg raising test on intracranial pressure and cerebral autoregulation in brain injured patients: a physiological observational study

BackgroundThe use of the passive leg raising (PLR) is limited in acute brain injury (ABI) patients with increased intracranial pressure (ICP) since the postural change of the head may impact on ICP and cerebral autoregulation. However, the PLR use may prevent a positive daily fluid balance, which had been recently associated to worse neurological outcomes. We therefore studied early and delayed effects of PLR on the cerebral autoregulation of patients recovering from ABI.Materials and methodsThis is a Prospective, observational, single-center study conducted in critically ill patients admitted with stable ABI and receiving invasive ICP monitoring, multimodal neuromonitoring and continuous hemodynamic monitoring. The fluid challenge consisted of 500 mL of crystalloid over 10 min; fluid responsiveness was defined as cardiac index increase ≥ 10%. Comparisons between different variables at baseline and after PLR were made by paired Wilcoxon signed-rank test. The correlation coefficients between hemodynamic and neuromonitoring variables were assessed using Spearman’s rank test.ResultsWe studied 23 patients [12 patients (52.2%) were fluid responders]. The PLR significantly increased ICP [from 13.7 (8.3–16.4) to 15.4 (12.0–19.2) mmHg; p < 0.001], cerebral perfusion pressure (CPP) [from 51.1 (47.4–55.6) to 56.4 (49.6–61.5) mmHg; p < 0.001] and the pressure reactivity index (PRx) [from 0.12 (0.01–0.24) to 0.43 (0.34–0.46) mmHg; p < 0.001]. Regarding Near Infrared Spectroscopy (NIRS)-derived parameters, PLR significantly increased the arterial component of regional cerebral oxygen saturation (O2Hbi) [from 1.8 (0.8–3.7) to 4.3 (2.5–5.6) μM cm; p < 0.001], the deoxygenated hemoglobin (HHbi) [from 1.6 (0.2–2.9) to 2.7 (1.4–4.0) μM cm; p = 0.007] and total hemoglobin (cHbi) [from 3.6 (1.9–5.3) to 7.8 (5.2–10.3): p < 0.001]. In all the patients who had altered autoregulation after PLR, these changes persisted ten minutes afterwards. After the PLR, we observed a significant correlation between MAP and CPP and PRx.ConclusionsIn ABI patient with stable ICP, PLR test increased ICP, but mostly within safety values and thresholds. Despite this, cerebral autoregulation was importantly impaired, and this persisted up to 10 min after the end of the maneuvre. Our results discourage the use of PLR test in ABI even when ICP is stable.

Impact of rapid sequential combination therapy on distinct haemodynamic measures in newly diagnosed pulmonary arterial hypertension.

In pulmonary arterial hypertension (PAH), upfront combination therapy with ERA and PDE5i is associated with a reduction in morbidity and mortality events and improves standard haemodynamics, but data remain limited. Aims of this study were (i) to capture detailed haemodynamic effects of rapid sequential dual combination therapy in patients with newly diagnosed PAH; (ii) to monitor the impact of treatment initiation on clinical variables and patients' risk status, and (iii) to compare the treatment effect in patients with 'classical PAH' and 'PAH with co-morbidities'. Fifty patients (median age 57 [42-71] years, 66% female) with newly diagnosed PAH (76% idiopathic) were treated with a PD5i/sGC-S or ERA, followed by addition of the respective other drug class within 4weeks. All patients underwent repeat right heart catheterization (RHC) during early follow-up. At early repeat RHC (7±2months), there were substantial reductions in mean pulmonary artery pressure (mPAP: 52.2±13.5 to 39.0±10.6mmHg; -25.3%), and pulmonary vascular resistance (PVR: 12.1±5.7 to 5.8±3.1 WU; -52.1%), and an increase in cardiac index (2.1±0.4 to 2.7±0.7mL/min/m2; +32.2%) (all P<0.05). Haemodynamic improvements correlated with improved clinical parameters including 6-min walking distance (336±315 to 389±120m), NTproBNP levels (1.712±2.024 to 506±550ng/L, both P<0.05) and WHO-FC at 12months, resulting in improved risk status, and were found in patients with few (n=37) or multiple cardiovascular co-morbidities (BMI>30kg/m2, hypertension, diabetes, coronary artery disease [≥3]; n=13), albeit baseline PVR in PAH patients with multiple co-morbidities was lower (9.3±4.4 vs. 13.1±5.9 WU) and PVR reduction less pronounced compared with those with few co-morbidities (-42.7% vs. -54.7%). However, comprehensive haemodynamic assessment considering further variables of prognostic relevance such as stroke volume index and pulmonary artery compliance showed similar improvements among the two groups (SVI: +50.0% vs. +49.2%; PAC: 91.7% vs. 100.0%). Finally, the 4-strata risk assessment approach was better able to capture treatment response as compared with other approaches, particularly in patients with co-morbidities. Rapid sequential combination therapy with PDE5i/sGC-S and ERA substantially ameliorates cardiopulmonary haemodynamics at early follow-up in patients without, and to a lesser extent, with cardiovascular co-morbidities. This occurs in line with improvements of clinical parameters and risk status.

Changes in central venous pressure during a fluid challenge have limited value for guiding fluid therapy.

To evaluate whether changes in central venous pressure during fluid expansion and baseline cyclic respiratory variation in the central venous pressure amplitude (RespCVP) curve could be used to discriminate between fluid responders and nonresponders. This prospective observational study included critically ill adult patients who underwent fluid expansion in the form of a fluid bolus or fluid challenge with crystalloids. All patients were under mechanical ventilation and adequately sedated. We determined the central venous pressure at baseline (CVPT0) and the changes at 5 (ΔCVPT5), 10 (ΔCVPT10) and 15 (ΔCVPT15) minutes during fluid infusion. We also measured the RespCVP at baseline. Fluid responsiveness was defined as a cardiac index increase of ≥ 15%. The study included 30 patients (11 responders and 19 nonresponders). The CVPT0 and the changes after a fluid challenge at all three time points did not adequately predict fluid responsiveness, as determined by their area under the curve values (CVPT0: 0.70, (95%CI: 0.49 - 0.90; ΔCVPT5: 0.78, (95%CI: 0.57 - 0.99; ΔCVPT10: 0.63, (95%CI: 0.39 - 0.88; ΔCVPT15: 0.68, ((95%CI: 0.45 - 0.92). The RespCVP at baseline also had a poor performance (area under the curve: 0.70; 95%CI: 0.50 - 0.91). Changes in central venous pressure have limited value in predicting fluid responsiveness.

Mean systemic filling pressure and venous return to assess the effects of passive leg raising and volume expansion in acute circulatory failure patients: a posthoc analysis of a multi-centre prospective study

The main aim of the study was to investigate the behaviours of the mean systemic filling pressure (Pmsf), calculated by the mathematical method, and its derived variables of venous return after volume expansion (VE) and passive leg raising (PLR), with analysis according to fluid and PLR responsiveness. This was a post-hoc analysis of a multicentre prospective study. We included 202 mechanically ventilated patients with acute circulatory failure. Pmsf, dVR (difference between Pmsf and central venous pressure [CVP]), and resistance to venous return (RVR) were calculated before/after PLR and before/after VE. Fluid- and PLR-responsiveness were defined according to the increase in cardiac index (CI) >15% after VE and >10% after PLR, respectively. Pmsf increased significantly after VE and PLR in both fluid and PLR-responder and non-responder groups. In fluid-responder patients, the increase in dVR was significantly higher than in non-responder group (1.5 [IQR:1.0-2.0] vs. 0.3 [IQR:-0.1-0.6] mmHg, p < 0.001) because of the larger increase in CVP relative to Pmsf in the non-responder group. The same findings were observed after PLR. RVR significantly decreased only in the fluid-responder and PLR-responder groups after VE and PLR. Venous return, derived from the mathematical model, increased in preload-dependent patients after VE and PLR because of the larger increases in Pmsf relative to CVP and the decreases in RVR. In preload-independent patients, VR did not change because of the larger rise in CVP compared to Pmsf after VE and PLR. These findings agree with the physiological model of circulation described by Guyton.

Responsiveness to Infusion Load under Regional Anesthesia after Off-Pump Coronary Artery Bypass Graft Surgery

Objective. To evaluate the effect of erector spinae plane block (ESPB) and epidural anesthesia on responsiveness to infusion load after coronary bypass surgery on a beating heart.Materials and methods. A prospective randomized single-center study included 45 patients who were grouped into 3 equal arms based on anesthesia techniques: general anesthesia in combination with ESPB (GA+ESPB), general anesthesia and epidural anesthesia (GA+EA) and general anesthesia without regional techniques (GA). Patient’s response to volume loading was assessed using dynamic and orthostatic tests after transfer from the operating room and at the end of the first postoperative day. Passive leg raise (PLR) and standard bolus injection tests were done at the first stage; changes in hemodynamic parameters during verticalization were additionally evaluated at the second stage. Patients with 10% cardiac index (CI) increase after PLR test and 15% increase after bolus injection test were categorized as responders.Results. The concordance of obtained results in PLR and bolus injection tests for the GA+ESPB, GA+ EA and GA groups at the first stage was 0.53 (95% CI 0.12–0.94), 0.68 (95% CI 0.30–1.00) and 0.61 (CI 0.24–0.99), at the second stage — 0.70 (0.32–1.00), 0.84 (95% CI 0.55–1.00) and 0.82 (95% CI 0.47–1.00), respectively. There were no differences in distribution of responders between the groups. CI dynamics did not differ between the groups during verticalization, and there were no associations of CI changes during verticalization with the preceding PLR test results. The dynamics of troponin T and NT-proBNP did not differ between the groups.Conclusion. Methods of regional anesthesia (SPB or EA) do not significantly affect the responsiveness to infusion therapy in the postoperative period after coronary bypass surgery on a beating heart.

Treatment of patients with multiple organ dysfunction syndrome (MODS) with an electromagnetic field coupled to biorhythmically defined impulse configuration: the MicrocircMODS study

BackgroundTo potentially improve impaired vasomotion of patients with multiple organ dysfunction syndrome (MODS), we tested whether an electromagnetic field of low flux density coupled with a biorhythmically defined impulse configuration (Physical Vascular Therapy BEMER®, PVT), in addition to standard care, is safe and feasible and might improve disturbed microcirculatory blood flow and thereby improve global haemodynamics.MethodsIn a prospective, monocentric, one-arm pilot study, 10 MODS patients (APACHE II score 20–35) were included. Patients were treated, in addition to standard care, for 4 days with PVT (3 treatment periods of 8 min each day; day 1: field intensity 10.5 μT; day 2:14 μT, day 3:17.5 μT; day 4:21.0 μT). Primary endpoint was the effect of PVT on sublingual microcirculatory perfusion, documented by microvascular flow index (MFI). Patient safety, adverse events, and outcomes were documented.ResultsAn increase in MFI by approximately 25% paralleled 4-day PVT, with the increase starting immediately after the first PVT and lasting over the total 4-day treatment period. Concerning global haemodynamics (secondary endpoints), halving vasopressor use within 24 h, and haemodynamic stabilisation paralleled 4-day PVT with an increase in cardiac index, stroke volume index, and cardiac power index by 30%–50%. No adverse events (AEs) or serious adverse events (SAEs) were classified as causally related to the medical product (PVT) or study. Three patients died within 28 days and one patient between 28 and 180 days.ConclusionPVT treatment was feasible and safe and could be performed without obstruction of standard patient care. An increase in microcirculatory blood flow, a rapid reduction in vasopressor use, and an improvement in global haemodynamics paralleled PVT treatment. Findings of this pilot study allowed forming a concept for a randomized trial for further proof.Graphical abstract

Ambulatory Monitoring of Cerebrovascular Responses to Upright Posture and Walking in Older Adults With Heart Failure

Insufficient cardiac output in individuals with heart failure (HF) limits daily functioning and reduces quality of life. Although lower cerebral perfusion, secondary to limitations in cardiac output, has been observed during moderate-intensity efforts, individuals with HF also may be at risk for lower perfusion during even low-intensity ambulatory activities. We determined whether HF is associated with an altered cerebrovascular response to low-intensity activities representative of typical challenges of daily living. In this study, we monitored central hemodynamics and middle cerebral artery blood velocity (MCAv) and cerebral tissue oxygenation (near-infrared spectroscopy) in 10 individuals with HF (aged 78 ± 4 years; left ventricular ejection fraction 20%-61%) and 13 similar-aged controls (79 ± 8 years; 52%-73%) during 3 randomized transitions, as follows: (i) supine-to-standing; (ii) sitting-to-slow-paced over-ground walking; and (iii) sitting-to-normal-paced over-ground walking. Throughout supine, sitting, standing, and both walking conditions, individuals with HF had lower cardiac index and cerebral tissue oxygenation than controls (P < 0.05), and MCAv was lower across the range of blood pressure in HF patients (P= 0.051) and during walking only (P= 0.011). Individuals with HF had an attenuated increase in stroke volume index and cardiac index during normal-paced walking, compared to controls (P < 0.01). The indices of cerebral perfusion from MCAv and cerebral oxygenation were lower during ambulatory activities in individuals with HF; however, relationships between MCAv and blood pressure were not different between those with HF and controls, indicating no difference in static cerebral autoregulation.

Hemodynamic Effects of Awake Prone Positioning With COVID-19 Acute Respiratory Failure.

Awake prone positioning (PP) reduces need for intubation for patients with COVID-19 with acute respiratory failure. We investigated the hemodynamic effects of awake PP in non-ventilated subjects with COVID-19 acute respiratory failure. We conducted a single-center prospective cohort study. Adult hypoxemic subjects with COVID-19 not requiring invasive mechanical ventilation receiving at least one PP session were included. Hemodynamic assessment was done with transthoracic echocardiography before, during, and after a PP session. Twenty-six subjects were included. We observed a significant and reversible increase in cardiac index (CI) during PP compared to supine position (SP): 3.0 ± 0.8 L/min/m2 in PP, 2.5 ± 0.6 L/min/m2 before PP (SP1), and 2.6 ± 0.5 L/min/m2 after PP (SP2, P < .001). A significant improvement in right ventricular (RV) systolic function was also evidenced during PP: The RV fractional area change was 36 ± 10% in SP1, 46 ± 10% during PP, and 35 ± 8% in SP2 (P < .001). There was no significant difference in PaO2 /FIO2 and breathing frequency. CI and RV systolic function are improved by awake PP in non-ventilated subjects with COVID-19 with acute respiratory failure.