Renal Venous Flow Research Articles

Abnormal Venous Flow in Pregnant Women with Mild Right Ventricular Dysfunction in Repaired Tetralogy of Fallot: A Clinical Model for Organ Dysfunction in Preeclampsia.

Background: Pregnant women with congenital heart disease carry a high risk of complications, especially when cardiac function is suboptimal. Increasing evidence suggests that impaired right ventricular (RV) function has a negative effect on placental function, possibly through venous congestion. We report a case series of hepatic and renal venous flow patterns in pregnant women with right ventricular dysfunction after repaired Tetralogy of Fallot (ToF), relative to those observed in normal pregnancy and preeclampsia. Methods: At 20-24 weeks pregnancy, RV function was measured by echocardiography and by cardiovascular magnetic resonance in women with repaired ToF. Combined Doppler-ECG of the hepatic and renal interlobular veins were performed in three women with asymptomatic right ventricular dysfunction. Venous impedance index and pulse transit time were measured and classified as abnormal at >75th and <25th reference percentile, respectively. Results: All three women showed dilated RV and mildly impaired RV function. Both hepatic and intrarenal Doppler flow waves were abnormal and very much resembled the patterns seen in preeclampsia. One of the three women had complications including ventricular tachycardia, intrauterine growth restriction, antenatal bleeding, emergency cesarean section and acute heart failure 2 days postpartum. Conclusions: Pregnant women with mild right ventricular dysfunction after repaired ToF show abnormal venous Doppler flow waves in the liver and kidneys, similar to those observed in preeclampsia. These findings are in line with reported observations on the association between impaired RV function, abnormal return of venous blood, venous congestion and organ dysfunction. The parallel with venous Doppler flow observations in preeclampsia suggest that the venous compartment might play an important role in the etiology of preeclampsia-induced organ dysfunction. Whether this phenomenon directly affects the uteroplacental circulation is to be assessed in future research.

Renal venous flow in different regions of the kidney are different and reflecting different etiologies of venous reflux disorders in septic acute kidney injury: a prospective cohort study

BackgroundAcute kidney injury (AKI) is a frequent complication of sepsis. While impaired renal venous reflux indicates renal congestion, the relationship between AKI outcomes and hemodynamic parameters remains debated. This study aimed to investigate the utility of renal venous flow patterns in various regions of septic patients and to explore the association between hemodynamic parameters and renal function prognosis.MethodsIn this single-center, prospective longitudinal study, adult sepsis patients diagnosed with AKI were enrolled. Renal ultrasonography was performed within 24 h of ICU admission (D1), then repeated at D3 and D5. Patterns of proximal renal venous flow (PRVF) and intrarenal venous flow (IRVF) patterns were confirmed by two blinded sonographers. Kaplan–Meier survival analysis was used to evaluate renal prognosis, and cumulative incidence curves were generated for renal function recovery time.ResultsThe study included 96 septic patients. Inconsistencies between PRVF and IRVF patterns occurred in 31.9%, with PRVF patterns being more severe in 88% of these. A relatively strong correlation was observed between PRVF and CVP, but this trend was less evident in IRVF. For RVSI of PRVF at ICU admission, the AUC to predict 28-day renal function prognosis was 0.626 (95% CI 0.502–0.750, P = 0.044), while combined PRVF and IRVF had a higher predictive ability (AUC 0.687, 95% CI 0.574–0.801, P = 0.003). The 28-day renal prognosis was poorer in the PRVF 5-day non-improvement group compared to the 3-day improvement group (P = 0.001) and 5-day improvement group (P = 0.012). Patients with a persistent monophasic PRVF pattern within 5 days had a worse prognosis than the non-monophasic group (P = 0.005).ConclusionsOur study reveals that patterns of PRVF and IRVF are not entirely congruent, stepwise evaluation is useful in determining the intervention site for renal vein reflux disorders. Combined PRVF and IRVF had a higher predictive ability for 28-day renal function prognosis. Early improvement in renal venous congestion is crucial for better renal function prognosis.This study is registered with ClinicalTrials.gov, number NTC06159010. Retrospectively registered 28 November 2023.

Associations of different definitions of iron deficiency with cardiac structure and function, congestion, exercise capacity and prognosis in heart failure

Abstract Background It is uncertain how best to diagnose iron deficiency (ID) in patients with heart failure (HF) as different ID definitions have been proposed with discordant results. Objectives To assess the relationship of different ID definitions with cardiac structure and function, congestion, exercise capacity, and prognosis in outpatients with HF. Methods ID was defined according to guidelines (G-ID: ferritin &amp;lt;100 ng/mL or ferritin 100-299 ng/mL with transferrin saturation [TSAT] &amp;lt;20%) or as TSAT &amp;lt;20%. Alternative definitions (iron &amp;lt;13 ¼mol/L, ferritin &amp;lt;100 and &amp;lt;300 ng/mL) were explored. Relationship with rest and exercise ultrasound findings, cardiopulmonary exercise testing and a composite endpoint of cardiovascular hospitalisations or all-cause mortality were assessed. Results Of 1502 patients (72% with left ventricular ejection fraction [LVEF] ≥50%), 471 (31%) had TSAT &amp;lt;20%, while 728 (48%) had G-ID. Compared to those without ID, patients with TSAT &amp;lt;20% or G-ID showed impaired cardiac structure and function at rest and peak exercise and lower peak oxygen consumption; they were also more likely to display a discontinuous renal venous flow pattern and more lung B-lines. Only TSAT &amp;lt;20% was associated with significant inferior vena cava dilatation. Lower TSAT, iron and haemoglobin were associated with more severe effort intolerance and ultrasound signs of congestion, while ferritin and LVEF were not (Picture 1). During a median follow-up of 16 months, 62 (4%) patients died, and 244 (16%) were hospitalised for cardiovascular reasons. No patients were hospitalised immediately after the enrolment visit because of clinical findings. At Kaplan-Meier analyses, TSAT &amp;lt;20% was associated with a greater risk of adverse events, as were iron ≤13 ¼mol/L, ferritin ≥300 ng/mL and &amp;lt;100 ng/mL (p &amp;lt;0.01 vs ferritin 100-299 ng/mL) and G-ID (Picture 2). After adjusting for age, sex, diabetes, haemoglobin, estimated glomerular filtration rate (eGFR), NT-proBNP, rest LVEF and peak VO2 &amp;lt;16 mL/kg/min, TSAT &amp;lt;20% and iron ≤13 ¼mol/L were associated with worse outcomes (hazard ratio 2.41, 95% confidence interval 1.85-3.14 and 1.90, 1.46-2.47), while G-ID or ferritin &amp;lt;100 or &amp;lt;300 ng/mL were not (Picture 1). Conclusions In outpatients with HF, TSAT &amp;lt;20% is more consistently associated with echocardiographic signs of poorer functional capacity and multi-organ congestion than other ID definitions. TSAT &amp;lt;20% and iron ≤13 ¼mol/L, but not G-ID or ferritin-based ID, seem to predict a worse prognosis.Picture 1Picture 2

Renal Arterial and Venous Doppler in Cardiorenal Syndrome: Pathophysiological and Clinical Insights.

In recent decades, there has been considerable effort in investigating the clinical utility of renal Doppler measurements in both cardiovascular and renal disorders. In particular, a measure of renal arterial resistance, the renal resistive index (RRI), has been demonstrated to predict chronic kidney disease progression and acute kidney injury in different clinical settings. Furthermore, it is linked to a poorer prognosis in individuals suffering from chronic heart failure. Examining the renal venous flow through pulsed Doppler can offer additional insights into renal congestion and cardiovascular outcomes for these patients. This review seeks to summarize the existing data concerning the clinical significance of arterial and venous renal Doppler measurements across various cardiovascular and renal disease contexts.

#2999 Renal venous congestion as a predictor of poor prognosis in patients with acute decompensated heart failure

Abstract Background and Aims Systemic venous congestion in acute decompensated heart failure (ADHF) is associated with a risk of end-organ damage and high in-hospital mortality. We aimed to assess the prevalence and severity of renal venous congestion using venous excess ultrasound (VExUS) protocol in intensive care unit (ICU) patients with ADHF, and to evaluate the association between type of intra-renal venous blood flow, incidence of acute kidney injury (AKI), and in-hospital death. Method A prospective single-center study included 99 patients who were admitted to the ICU with ADHF (mean age 71.1 ± 12.54 years, 56 (56.6%) males). Inclusion criteria: age ≥18 years, ADHF II–IV, signed informed consent. Exclusion criteria: acute coronary syndrome, severe concomitant diseases, refusal to participate in the study. Upon admission, routine clinical, laboratory and instrumental examinations, lung ultrasound using the BLUE protocol, and assessment of venous congestion using the pulse-wave dopplerography were performed. The presence of continuous blood flow was regarded as the absence of renal venous congestion, while intermittent (biphasic and monophasic blood flow) indicated venous congestion. The diagnosis of ADHF and AKI was established based on generally accepted criteria in accordance with modern international recommendations. All patients received optimal drug therapy. The end point was defined as death from cardiovascular causes during hospitalization. Statistical analysis was performed using SPSS Statistics, version 26.0. Results Upon admission, continuous renal venous blood flow was detected in 17 (17.2%) patients, intermittent in 82 (82.8%): biphasic in 47 (47.5%) and monophasic in 35 (35.3%). The patient groups were comparable in gender, age, frequency of coronary heart disease, diabetes mellitus, anemia. Atrial fibrillation was more common in case of monophasic (p &amp;lt; 0.006), and arterial hypertension in patients with continuous venous blood flow (p &amp;lt; 0.001). Patients with renal venous congestion, compared with patients without signs of congestion, had more severe heart failure: swollen neck veins: 5 (29.4%) vs 21 (45%) vs 28 (60%), p &amp;lt; 0.001; hepatomegaly 12 (72.6%) vs 40 (85.1%) vs 31 (88.6%), p &amp;lt; 0.001; edema 8 (47.3%) vs 40 (85.1%) vs 24 (68.6%), p &amp;lt; 0.001; NYHA functional class IV 8 (47.1%) vs 32 (68.1%) vs 26 (74.6%), p &amp;lt; 0.001; more B-lines on lung ultrasound, M+SD 28.82 ± 8.91 vs 34.38 ± 9.64 vs 35.37 ± 8.72, p &amp;lt; 0.001, higher NTproBNP levels, pg/l, Ме(IQR) 2100 (1800;4560) vs 3418 (2300;8434) vs 4100 (2500;9282), p &amp;lt; 0.001, and albuminuria levels mg/g, Ме(IQR) 85 (29;145) vs 127 (49;248) vs 139 (64;245), p &amp;lt; 0.001. The incidence of AKI (4 (23.5%) vs 23 (49%) vs 31 (88.6%), p &amp;lt; 0.001), and in-hospital death (0 (0) vs 11 (23.4%) vs 12 (34.3%), p &amp;lt; 0.003) was also higher in the group of patients with monophasic renal blood flow. The presence of renal venous congestion on admission was associated with an increased risk of death due to heart failure during hospitalization with RR 1.32 (95% CI: 1.16-2.64), p &amp;lt; 0.001, and RR 1.64 (95% CI: 1.48-2.83), p &amp;lt; 0.001 in patients with biphasic and monophasic renal venous blood flow respectively, and with development of AKI RR 3.29 (95% CI: 1.50-7.24), p &amp;lt; 0.003 in patients with monophasic renal venous blood flow. Conclusion In ICU patients with ADHF, the presence of renal venous congestion, assessed on admission with Doppler ultrasound of the intrarenal veins using the VEXUS protocol, is associated with a high risk of developing AKI and in-hospital death.

#2848 Persistent albuminuria is a marker of persistent congestion in patients with chronic heart failure

Abstract Background and Aims Albuminuria is prevalent in patients with heart failure (HF) and associated with poor prognosis. Initial reports indicate albuminuria as a congestion marker in HF. Frequency and associations of persistent albuminuria with kidney function, NT-proBNP and venous congestion in this population are not clearly understood. We aimed to evaluate the dynamics of albuminuria and its relationship with congestion and renal function in patients with chronic HF (CHF). Method The study included patients ≥18 years, observed in an outpatient HF center, who signed an informed consent. Patients receiving renal replacement therapy, with cancer or primary kidney diseases were excluded. The visits were carried out with an interval of 3 months. During each visit we performed routine physical examination, laboratory tests (NT-proBNP, urine albumin/creatinine ration (uACR), and serum creatinine) and pulse-wave Dopplerography to assess renal venous blood flow. Persistent albuminuria was defined as maintaining an uACR &amp;gt; 30 mg/g on two visits. Albuminuria level was assessed according to KDIGO guidelines 2012 (A1, A2, A3). The absence of venous congestion was defined as continuous renal blood flow, while venous congestion - as intermittent (biphasic or monophasic) blood flow. A P value &amp;lt;0.05 was considered statistically significant. We prospectively included 103 patients with CHF (46% male, mean age - 70 (61;75) Me (IQR) years, 53% with reduced ejection fraction (EF), mean EF 45(34;53)%, 92% hypertensive, 60% with atrial fibrillation, 34% with diabetes mellitus type 2, 51% with chronic kidney disease (CKD), 43% with coronary heart disease). Results Mean uACR values at the 1st visit was 18(8;56) mg/g, at the 2nd visit - 11(0;35) mg/g. The frequency of albuminuria levels at the 1st visit were A1-66%, A2-26%, A3-8%; at the 2nd visit – A1-73%, A2-23%, A3-4%. Persistent albuminuria was detected in 37 patients (36%). The mean values of albuminuria were higher in the persistent albuminuria group on the 1st visit (76(39;222) vs 10.5(0;19.5) for patients with and without persistent albuminuria, p&amp;lt;0.001) and on the 2nd visit (94(44;176) vs 7(0;13), p &amp;lt; 0.001). The patient groups were comparable in gender, age, frequency of comorbidities, EF. The administration of disease-modifying therapy was the same in the groups, however, the dose of loop diuretic was higher in the group of persistent albuminuria (20 (10;75) vs 10(5;20) mg respectively, p = 0.024 (doses in terms of furosemide)). Serum creatinine level was 95(79;121) mmol/l; GFR (CKD-EPI 2021)- 69(52;88) mL/min/ 1.73 m2 at the 1st visit. Kidney function did not statistically differ in the groups with and without persistent albuminuria (at the 1st visit eGFE - 63(52;87) vs 70 (50;90) mL/min/1.73 m2, p = 0.52 and the 2nd visit eGFR- 68(48;85) vs 66 (48;89) mL/min/1.73, p = 0.65 respectively). The level of NT-proBNP was higher in patients with persistent albuminuria during the 1st (926 (472;1820) vs 550(260;919), pg/ml p = 0.04) and the 2nd visit (1244(987;2000) vs 593(264;1405), pg/ml, p = 0.0008). Intermittent renal veins blood flow on the 2nd visit was observed in 26 patients (25%). In patients with persistent albuminuria persistence of intermittent venous renal blood flow was more frequently than in patients without it (43% vs 7%, p = 0.017, respectively). Figs. 1 and 2 demonstrate that renal venous congestion was more severe in group of persistent albuminuria on visit 1st and 2nd respectively. Conclusion Persistent albuminuria over 3 mounts in patients with stable chronic heart failure is associated with persisting congestion (higher NT-proBNP levels and higher incidence and severity of renal venous congestion). There was no association between changes in albuminuria and changes in renal function.

&lt;b&gt;Evaluation of renal function in dogs using pulsed Doppler ultrasonography&lt;/b&gt;

Background: In human medicine, efforts have been made to evaluate venous blood flow in the kidneys to diagnose renal disease and estimate renal function. In dogs, previous studies have predicted renal function using the resistive index (RI) and pulsatility index (PI), which are derived from renal arterial blood flow velocity assessed via pulsed Doppler ultrasonography. However, to date, no study has been conducted on renal venous blood flow velocity in dogs. Aim: To investigate the relationship between renal venous blood flow velocity and renal function. Methods: Ten normal beagle dogs underwent blood tests and glomerular filtration rate (GFR) measurements. Pulsed Doppler ultrasonography was performed under sedation to measure the maximum venous flow velocity (Vmax), minimum venous flow velocity (Vmin), and venous impedance index (VII) in the renal and interlobular veins. The RI and PI were calculated from the renal and interlobular arteries. Results: Vmax and Vmin of the renal vein were negatively correlated with GFR in both kidneys. No significant correlations were found between other measures and GFR. These results suggest a relationship between GFR and venous flow velocity in the renal veins assessed using pulsed Doppler ultrasonography. Conclusion: These findings demonstrate the potential of this methodology as a new tool for predicting abnormalities in the renal venous blood flow and renal congestion in dogs. Further large-scale studies and comparisons between healthy dogs and dogs with impaired renal function are needed to validate this relationship.

Features of changes in the heart, blood vessels and internal organs in men with hypertension, depending on the value of the body mass index

Objective: study of the features of changes in the heart, blood vessels and internal organs (liver and kidneys) in men with hypertension, depending on the BMI value. Materials and methods: 194 men aged 25 to 63 with hypertension were examined. All the examined patients were divided into 3 groups depending on the BMI value. All patients included in the study were determined by serum creatinine (calculated by GFR), glucose, aspartate aminotransferase, alanine aminotransferase, lipid spectrum, uric acid. In addition, echocardiography, ultrasound of the kidneys with measurement of arterial and venous blood flow through the main vessels of the kidneys, ultrasound of the liver were performed. In the future, the groups were compared with each other according to the studied laboratory and instrumental data. Results: as the BMI values increased, the indicators of alanylaminotransferase, IFDS, RWT LV, MMLV, IMLV, the size of the right lobe of the liver, the incidence of hepatosteatosis significantly increased. Adherence to antihypertensive therapy in the selected groups ranged from 18,9 to 20,5%. Bilateral disorders of outflow through the renal veins were 1,8 times more common among people with normal BMI compared with obesity (p&lt;0.05). Conclusion: among the examined young men with hypertension, there are features of an unfavorable "cardiological" profile and low adherence to antihypertensive therapy, which, as the age and length of the disease increases, is associated with a high risk of developing associated clinical conditions in the future. In male patients with hypertension and obesity, the incidence of hepatosteatosis is 100%, having an additional adverse effect on cardiovascular risk. The revealed features of renal venous blood flow among patients with hypertension deserve further investigation.

Doppler-based evaluation of intrarenal venous flow as a new tool to predict acute kidney injury: A systematic review and meta-analysis

Congestion is a common complication in the critical care setting, these patients are at increased risk of developing acute kidney injury (AKI). Congestive nephropathy (CN) has recently been described as a mechanism of worsening renal function, and evaluation of renal venous flow by pulsed Doppler (PD) is a useful tool to assess the presence of renal vein congestion. We comprehensively explore the ability of the PD in the evaluation of the intrarenal venous flow (IRVF) to predict the development of AKI in critically ill patients.We searched Pubmed-MEDLINE, Scopus, Embase, and Cochrane Library of Systematic Reviews (to 31th December 2021). We evaluated the association between Doppler-based Intrarenal venous flow demodulation and AKI. CN was defined as the presence of a pulsatile pattern (biphasic or monophasic) in the PD.A total of 4 articles (660 patients) were included in our systematic review, three of these in the metanalysis (413 patients): one study was excluded because its data were inadequate for pooling. Two studies originated in Europe and the other two in the United States. AKI occurrence ranged between 34 and 68%. Patients who developed AKI had a significant difference in PD pattern (continuous vs. pulsatile) in the IRVF (RR=0.46; 95% CI 0.28–0.76). Nevertheless, a large heterogeneity was observed among the studies (I2=68.7%; p=0.04).Albeit preliminary, these findings suggest that the presence of a pulsatile pattern in the PD of the IRVF may be involved in the development of AKI in the critically ill patient. The effect of alterations in the IRVF and renal function warrant further investigation.

Dynamic volume status assessment with the VExUS score after heart valve surgery complicated by acute kidney injury: a case series

Background: Fluid overload is an independent risk factor for acute kidney injury after cardiac surgery. An objective volume status assessment remains an unsolved clinical problem.Objective: To analyze the relationship between the dynamic changes in splanchnic blood flow patterns (portal, hepatic, and interlobar renal veins), reflecting the venous congestion severity, and severity of renal dysfunction in the studied patients.Methods: From February to May 2023, 3 patients after open heart surgery developed acute kidney injury in the postoperative period: 2 of them required renal replacement therapy. In the perioperative period, all patients underwent Doppler ultrasonographic assessment of the splanchnic blood flow according to the venous excess ultrasound (VExUS) score.Results: The most distinct changes in blood flow patterns were observed in portal and interlobar renal veins. Two anuric patients requiring renal replacement therapy had a pulsatile portal venous flow with systolic flow reversal that indicated severe venous congestion and biphasic renal venous flow. After restoration of urine output in 1 patient, the blood flow pattern in the portal vein returned to the normal pattern. In another patient, the blood flow remained pulsatile, which manifested itself by persisting clinical signs of overhydration. In the third patient, the portal blood flow also was pulsatile but had no systolic flow reversal. The renal blood flow was biphasic, although it was initially continuous. After restoration of urine output and overhydration improvement, the blood flow pattern returned to the preoperative pattern.Conclusion: In the studied patients, the dynamic assessment of splanchnic blood flow using the VExUS score allowed to objectively assess the venous congestion severity and served as an additional criterion for initiating renal replacement therapy in case of acute kidney injury progression. Further research could validate this type of monitoring because its interpretation requires a comprehensive assessment due to moderate specificity. Received 21 June 2023. Revised 17 July 2023. Accepted 24 July 2023. Informed consent: The patients’ informed consent to use the records for medical purposes is obtained. Funding: The study did not have sponsorship. Conflict of interest: The authors declare no conflicts of interests. Contribution of the authors: The authors contributed equally to this article.

Bio-Humoral and Non-Invasive Haemodynamic Correlates of Renal Venous Flow Patterns across the Heart Failure Spectrum.

Background: We evaluated the bio-humoral and non-invasive haemodynamic correlates of renal congestion evaluated by Doppler renal venous flow (RVF) across the heart failure (HF) spectrum, from asymptomatic subjects with cardiovascular risk factors (Stage A) and structural heart disease (Stage B) to patients with clinically overt HF (Stage C). Methods: Ultrasound evaluation, including echocardiography, lung ultrasound and RVF, along with blood and urine sampling, was performed in 304 patients. Results: Continuous RVF was observed in 230 patients (76%), while discontinuous RVF (dRVF) was observed in 74 (24%): 39 patients had pulsatile RVF, 18 had biphasic RVF and 17 had monophasic RVF. Stage C HF was significantly more common among patients with dRVF. Monophasic RVF was associated with worse renal function and a higher urinary albumin-to-creatinine ratio (uACR). After adjusting for hypertension, diabetes mellitus, the presence of Stage C HF and serum creatinine levels, worsening RVF patterns were associated with higher NT-proBNP levels, worse right ventricular-arterial coupling, larger inferior vena cava and higher echo-derived pulmonary artery wedge pressure. This trend was confirmed when only patients with HF Stage C were analysed after adjusting for the left ventricle ejection fraction (LVEF). Conclusion: Abnormal RVF is common across the HF spectrum. Worsening RVF patterns are independently associated with increased congestion, worse non-invasive haemodynamics and impaired RV-arterial coupling. RVF evaluation could refine prognostic stratification across the HF spectrum, irrespective of LVEF.

Phenotyping congestion in acute heart failure by renal flow and right heart to pulmonary circulation coupling.

In acute heart failure (AHF), kidney congestion is basic to treatment and prognosis. Its aetiology is manifold and quite unexplored in details mainly regarding the right heart to pulmonary circulation (Pc) coupling. We investigated the right heart to kidney interrelationship by Doppler renal flow pattern, right atrial dynamics, and right ventricular (RV) function to Pc coupling in AHF. In 119 AHF patients, echocardiographic and renal Doppler data were analysed. Univariate and multivariate regression models were performed to define the determinants of a quantitative parameter of renal congestion, the renal venous stasis index (RVSI). When grouped according to different intra-renal venous flow patterns, no differences were observed in haemodynamics and baseline renal function. Nonetheless, patients with renal Doppler evidence of congestion showed a reduced RV function [tricuspid annular plane systolic excursion (TAPSE), S'-wave velocity, and fractional area change], impaired RV to Pc coupling [TAPSE/pulmonary artery systolic pressure (PASP) ratio], and right atrial peak longitudinal strain (RAPLS), along with signs of volume overload [increased inferior vena cava (IVC) diameters and estimated right atrial pressure]. Univariate and multivariate regression analyses confirmed TAPSE/PASP, RAPLS, and IVC diameter as independent determinants of the RVSI. RVSI was the only variable predicting the composite outcome (cardiac death, heart failure hospitalization, and haemodialysis). An easy-to-use echo-derived right heart score of four variables provided good accuracy in identifying kidney congestion. In AHF, the renal venous flow pattern combined with a right heart study phenotypes congestion and clinical evolution. Keys to renal flow disruption are an impaired right atrial dynamics and RV-Pc uncoupling. Integration of four right heart echocardiographic variables may be an effective tool for scoring the renal congestive phenotype in AHF.

Association between intrarenal venous flow from Doppler ultrasonography and acute kidney injury in patients with sepsis in critical care: a prospective, exploratory observational study

BackgroundIntrarenal venous flow (IRVF) patterns assessed using Doppler renal ultrasonography are real-time bedside visualizations of renal vein hemodynamics. Although this technique has the potential to detect renal congestion during sepsis resuscitation, there have been few studies on this method. We aimed to examine the relationship between IRVF patterns, clinical parameters, and outcomes in critically ill adult patients with sepsis. We hypothesized that discontinuous IRVF was associated with elevated central venous pressure (CVP) and subsequent acute kidney injury (AKI) or death.MethodsWe conducted a prospective observational study in two tertiary-care hospitals, enrolling adult patients with sepsis who stayed in the intensive care unit for at least 24 h, had central venous catheters placed, and received invasive mechanical ventilation. Renal ultrasonography was performed at a single time point at the bedside after sepsis resuscitation, and IRVF patterns (discontinuous vs. continuous) were confirmed by a blinded assessor. The primary outcome was CVP obtained at the time of renal ultrasonography. We also repeatedly assessed a composite of Kidney Disease Improving Global Outcomes of Stage 3 AKI or death over the course of a week as a secondary outcome. The association of IRVF patterns with CVP was examined using Student's t-test (primary analysis) and that with composite outcomes was assessed using a generalized estimating equation analysis, to account for intra-individual correlations. A sample size of 32 was set in order to detect a 5-mmHg difference in CVP between IRVF patterns.ResultsOf the 38 patients who met the eligibility criteria, 22 (57.9%) showed discontinuous IRVF patterns that suggested blunted renal venous flow. IRVF patterns were not associated with CVP (discontinuous flow group: mean 9.24 cm H2O [standard deviation: 3.19], continuous flow group: 10.65 cm H2O [standard deviation: 2.53], p = 0.154). By contrast, the composite outcome incidence was significantly higher in the discontinuous IRVF pattern group (odds ratio: 9.67; 95% confidence interval: 2.13–44.03, p = 0.003).ConclusionsIRVF patterns were not associated with CVP but were associated with subsequent AKI in critically ill adult patients with sepsis. IRVF may be useful for capturing renal congestion at the bedside that is related to clinical patient outcomes.Graphical abstract

Renal venous Doppler ultrasound – a new parameter for predicting outcomes in patients with decompensated heart failure

Aim. To assess the frequency, dynamics, and prognostic value of renal venous congestion using Doppler ultrasound in patients with decompensated heart failure (DHF).Materials and methods. A prospective, single-center study included 124 patients with DHF (mean age 70 ± 12 years, 51.6% were males), left ventricular ejection fraction (LVEF) 44 [34; 55] %, N-terminal pro B-type natriuretic peptide (NT-proBNP) 1,609 [591; 2,700] pg / ml. All patients underwent a standard physical examination and laboratory and instrumental tests, including the assessment of the NT-proBNP level. Renal venous blood flow was assessed using pulsed-wave Doppler ultrasound. The presence of continuous renal blood flow was considered as the absence of venous congestion, while intermittent blood flow (two-phase and single-phase flow) indicated venous congestion. Rehospitalization for DHF and reaching a composite endpoint (rehospitalization for DHF and cardiovascular mortality) within 12 months after discharge were selected as endpoints.Results. At admission, continuous renal venous blood flow was observed in 34 (27.4%) patients, intermittent renal venous blood flow was found in 90 (72.6%) patients: two-phase flow in 62 (50%) and single-phase flow in 28 (22.6%) patients with DHF. At discharge, 66 (53.2%) patients had intermittent renal venous blood flow: two-phase flow in 50 (40.3%) and single-phase flow in 16 (12.9%) patients. Correlations of renal venous congestion with the levels of NT-proBNP, serum iron, uric acid, creatinine, LVEF, systolic pressure in the pulmonary artery (SPPA), and the development of acute kidney injury (AKI) were revealed. Persistent renal venous congestion at discharge was significantly associated with a higher probability of rehospitalization for DHF (hazard ratio (HR) 1.93 95% confidence interval (CI) (1.017–3.67); p = 0.044) and a composite endpoint (HR 2.66, 95% CI (1.43–4.96); p = 0.002).Conclusion. In patients with DHF, it is necessary to evaluate renal venous blood flow using pulsed-wave Doppler ultrasound to stratify patients with development of cardiovascular complications within 12 months.

Multi-organ sonographic assessment of congestion has incremental prognostic value in outpatients with heart failure irrespective of left ventricular ejection fraction

Abstract Funding Acknowledgements Type of funding sources: None. Background Congestion is a key driver of symptoms, disease progression and prognosis for patients with heart failure (HF), irrespective of left ventricular ejection fraction (LVEF). However, clinically overt congestion is often undiagnosed unless severe. Recent research has shown that ultrasonographic quantification of systemic venous (i.e. inferior vena cava), renal venous and lung (B-lines) congestion is feasible and identifies HF patients with a worse prognosis. Purpose Whether a simultaneous multi-organ evaluation of congestion by ultrasound may improve risk stratification in HF is unknown. In the present study, we assessed signs of ultrasonographic congestion in the inferior vena cava, lungs and kidneys in HF patients across the LVEF spectrum and investigated their association with pathophysiology, clinical characteristics and prognosis. Methods We prospectively enrolled 326 patients with a prior clinical diagnosis of HF attending a routine follow-up visit. We also enrolled 102 consecutive patients with cardiovascular risk factors (including hypertension, type II diabetes mellitus or chronic ischaemic heart disease) and no history of HF; these latter patients had NT-proBNP levels &amp;lt;125 ng/L, LVEF &amp;gt;50%, and were not taking loop diuretics. All patients underwent a complete clinical assessment, blood and urine tests, and an ultrasound evaluation. Ultrasound congestion was defined as inferior vena cava ≥21 mm, highest tertile of lung B-lines or discontinuous renal venous flow. Results The final population consisted of 310 HF patients (median age 77 years, median NT-proBNP 1037 ng/L, 51% with LVEF &amp;lt;50%), and 101 subjects without HF. Among the 224 HF patients (72%) with no clinical signs of congestion, 95 (42%) had at least one sign of congestion by ultrasound (p&amp;lt;0.0001). HF patients with ≥2 ultrasound signs were older, had greater neurohormonal activation (i.e., higher NT-proBNP; Figure 1), lower urinary sodium concentration, and larger left atria despite similar LVEF. During a median follow-up of 13 (interquartile range 6–15) months, 77 HF patients (19%) died or were hospitalized for HF. HF patients without ultrasonographic evidence of congestion had a similar outcome to subjects without HF (reference; HR 1.02, 95% CI 0.86 – 1.35), while those with ≥2 ultrasound signs had the worst outcome (HR 26.7, 95% CI 12.4–63.6), even after adjusting for multiple clinical variables and NT-proBNP (Figure 2). Adding multi-organ assessment of congestion by ultrasound to a clinical model, including NT-proBNP, provided a 28% net reclassification improvement (p=0.03). Conclusion Simultaneous assessment of pulmonary, systemic venous and kidney congestion by ultrasound identifies a high prevalence of sub-clinical congestion associated with poor outcomes in HF, irrespective of LVEF. The speed of investigation, along with the widespread availability and relatively low cost of ultrasound, makes this protocol easy to implement for real-time assessment of congestion.

Doppler-based evaluation of intrarenal venous flow as a new tool to predict acute kidney injury: A systematic review and meta-analysis

Congestion is a common complication in the critical care setting, these patients are at increased risk of developing acute kidney injury (AKI). Congestive nephropathy (CN) has recently been described as a mechanism of worsening renal function, and evaluation of renal venous flow by pulsed Doppler (PD) is a useful tool to assess the presence of renal vein congestion. We comprehensively explore the ability of the PD in the evaluation of the intrarenal venous flow (IRVF) to predict the development of AKI in critically ill patients.We searched Pubmed-MEDLINE, Scopus, Embase, and Cochrane Library of Systematic Reviews (to 31th December 2021). We evaluated the association between Doppler-based Intrarenal venous flow demodulation and AKI. CN was defined as the presence of a pulsatile pattern (biphasic or monophasic) in the PD.A total of 4 articles (660 patients) were included in our systematic review, three of these in the metanalysis (413 patients): one study was excluded because its data were inadequate for pooling. Two studies originated in Europe and the other two in the United States. AKI occurrence ranged between 34 and 68%. Patients who developed AKI had a significant difference in PD pattern (continuous vs. pulsatile) in the IRVF (RR=0.46; 95% CI 0.28–0.76). Nevertheless, a large heterogeneity was observed among the studies (I2=68.7%; p=0.04).Albeit preliminary, these findings suggest that the presence of a pulsatile pattern in the PD of the IRVF may be involved in the development of AKI in the critically ill patient. The effect of alterations in the IRVF and renal function warrant further investigation.

The incremental value of multi-organ assessment of congestion using ultrasound in outpatients with heart failure.

We investigated the prevalence and clinical value of assessing multi-organ congestion by ultrasound in heart failure (HF) outpatients. Ultrasound congestion was defined as inferior vena cava of ≥21 mm, highest tertile of lung B-lines, or discontinuous renal venous flow. Associations with clinical characteristics and prognosis were explored. We enrolled 310 HF patients [median age: 77 years, median NT-proBNP: 1037 ng/L, 51% with a left ventricular ejection fraction (LVEF) <50%], and 101 patients without HF. There were no clinical signs of congestion in 224 (72%) patients with HF, of whom 95 (42%) had at least one sign of congestion by ultrasound (P < 0.0001). HF patients with ≥2 ultrasound signs were older, and had greater neurohormonal activation, lower urinary sodium concentration, and larger left atria despite similar LVEF. During a median follow-up of 13 (interquartile range: 6-15) months, 77 patients (19%) died or were hospitalized for HF. HF patients without ultrasound evidence of congestion had a similar outcome to patients without HF [reference; hazard ratio (HR) 1.02, 95% confidence interval (CI) 0.86-1.35], while those with ≥2 ultrasound signs had the worst outcome (HR 26.7, 95% CI 12.4-63.6), even after adjusting for multiple clinical variables and NT-proBNP. Adding multi-organ assessment of congestion by ultrasound to a clinical model, including NT-proBNP, provided a net reclassification improvement of 28% (P = 0.03). Simultaneous assessment of pulmonary, venous, and kidney congestion by ultrasound is feasible, fast, and identifies a high prevalence of sub-clinical congestion associated with poor outcomes.

Additional effects of diosmin in the treatment of arterial hypertension in patients with impaired renal venous blood flow

Objective: to estimate of the effect of diosmin in complex antihypertensive therapy on renal function in patients with hypertension and impaired renal venous blood flow.Materials and methods: we observed 147 patients with hypertension aged 40.86±8.27 with signs of bilateral impairment of venous blood flow in the kidneys, which, depending on the amount of therapy, were divided into 2 groups and 2 subgroups. The comparison group consisted of 57 AH patients with unchanged venous blood flow in both kidneys.Results: in the presence of impaired venous blood flow in the renal veins, the use of additional administration of diosmin allows maintaining or improving the filtration capacity of the kidneys. Additional monitoring of patients with impaired venous blood flow in the kidneys is required to assess the effectiveness of antihypertensive therapy with individual drugs with and without venoactive agents.Conclusion: the additional inclusion of diosmin in the complex antihypertensive therapy of patients with arterial hypertension and impaired venous blood flow to the kidneys can preserve and improve kidney function with normalization of GFR.

Evaluation of Renal Blood Flow in Dogs during Short-Term Human-Dose Epoprostenol Administration Using Pulsed Doppler and Contrast-Enhanced Ultrasonography.

Simple SummarySince there is a lack of information regarding how epoprostenol, a prostacyclin, affects canine renal blood flow (RBF), we investigated the effects of short-term administration of epoprostenol at human doses of 2, 5, and 10 ng/kg/min intravenously for 20 min on RBF in six healthy dogs under anesthesia. The effects of short-term administration were investigated. As the dose of epoprostenol increased, peak systolic and end diastolic velocities of the renal arteries, maximum and minimum venous flow velocities of the interlobular and renal veins, and heart rate all tended to increase. However, these increases were not significant. These results indicate that the administration of human doses of epoprostenol to dogs does not produce significant changes in renal or systemic circulation.Prostacyclin is an in vivo bioactive substance that regulates renal blood flow (RBF). Information regarding how epoprostenol, a prostacyclin preparation, affects RBF in dogs is lacking. We investigated the effects of short-term epoprostenol administration on RBF in six healthy dogs under anesthesia by administering it intravenously at human doses—2, 5, and 10 ng/kg/min for 20 min. RBF was evaluated before and during epoprostenol administration using pulsed Doppler ultrasonography, and renal perfusion was evaluated using contrast-enhanced ultrasonography. Effects on renal and systemic circulation were evaluated by measuring systolic arterial, mean arterial, diastolic arterial, pulmonary arterial, mean right atrial, and pulmonary capillary wedge pressures; heart rate; and cardiac output. Kruskal–Wallis and Bonferroni multiple comparison tests and Spearman’s rank correlation coefficient were used for statistical analyses. As epoprostenol dosage increased, the peak systolic and end diastolic velocity of the renal artery, maximum and minimum venous flow velocities of the interlobular and renal veins, and heart rate all tended to increase, although not significantly. Our results indicate that human-dose epoprostenol administration in dogs does not cause significant changes in renal or systemic circulation. However, the human doses used may have been too low to produce a clinical effect in dogs.

Perioperative Doppler measurements of renal perfusion are associated with acute kidney injury in patients undergoing cardiac surgery

Acute kidney injury (AKI) is a frequent and severe complication in cardiac surgery. Normal renal function is dependent on adequate renal perfusion, which may be altered in the perioperative period. Renal perfusion can be assessed with Doppler measurement. We aimed to determine the association between Doppler measurements of renal perfusion and the development of AKI. This was a prospective, observational study of 100 patients with ≥ one risk factor for postoperative AKI undergoing open-heart surgery. Doppler ultrasound examinations were performed before surgery and on the first and fourth postoperative day. AKI was defined according to the KDIGO criteria and subdivided into mild (KDIGO stage 1) and severe AKI (KDIGO stage 2 + 3). Thirty-three patients developed AKI, 25 developed mild and eight developed severe AKI. Abnormal renal venous flow pattern on the first postoperative day was significantly associated with the development of severe AKI (OR 8.54 (95% CI 1.01; 72.2), P = 0.046), as were portal pulsatility fraction (OR 1.07 (95% CI 1.02; 1.13), P = 0.005). Point-of-care Doppler ultrasound measurements of renal perfusion are associated with the development of AKI after cardiac surgery. Renal and portal Doppler ultrasonography can be used to identify patients at high risk or very low risk of AKI after cardiac surgery.