Value of Renal Vascular Doppler Sonography in Cardiorenal Syndrome Type 1.

OBJECTIVES: Worsening of renal function in a patient with acute decompensated heart failure is called cardiorenal syndrome (CRS) type 1. Recent studies have shown an association of persistent systemic venous congestion with renal dysfunction. This trial was set up to investigate the changes of renal Doppler parameters with diuretic therapy in patients with CRS type 1. METHODS: Cases of CRS type 1 were identified among patients hospitalized for decompensated heart failure. Serial measurements of the renal venous impedance index (VII) and arterial resistive index (ARI) were calculated by pulsed wave Doppler sonography. RESULTS: A total of 30 patients who had creatinine improvement with diuresis (group 1) and 34 patients without any improvement (group 2) were analyzed. Patients in group 1 had higher median VII and ARI (VII, 0.86 versus 0.66; P < .001; ARI, 0.78 versus 0.65; P < .001) on admission. A high ARI on admission (odds ratio, 6.25; 95% confidence interval, 1.84-14.3; P = .003) predicted the improvement of serum creatinine levels with diuretic therapy independent of confounding factors in patients with CRS type 1. CONCLUSIONS: Renal vascular Doppler parameters might offer guidance on the diagnostic and therapeutic strategies in prescribing decongestive therapy for decompensated heart failure.

Electrocardiographic Time-Intervals Waveforms as Potential Predictors for Severe Acute Kidney Injury in Critically Ill Patients.

Background: Acute kidney injury (AKI) is common in critically ill patients admitted to intensive care units (ICU) and is frequently associated with poorer outcomes. Hence, if an indicator is available for predicting severe AKI within the first few hours of admission, management strategies can be put into place to improve outcomes. Materials and methods: This was a prospective, observational study, involving 63 critically ill patients, that aimed to explore the diagnostic accuracy of different Doppler parameters in predicting AKI in critically ill patients from a mixed ICU. Participants were enrolled at ICU admission. All underwent ultrasonographic examinations and hemodynamic assessment. Renal Doppler resistive index (RDRI), venous impedance index (VII), arterial systolic time intervals (a-STI), and venous systolic time intervals (v-STI) were measured within 2 h from ICU admission. Results: Cox proportional hazards models, including a-STI, v-STI, VII, and RDRI as independent variables, returned a-STI as the only putative predictor for the development of AKI or severe AKI. An overall statistically significant difference (p < 0.001) was observed in the Kaplan−Meier plots for cumulative AKI events between patients with a-STI higher or equal than 0.37 and for cumulative severe AKI-3 between patients with a-STI higher or equal than 0.63. As assessed by the area under the receiver operating curves (ROC) curves, a-STI performed best in diagnosing any AKI and/or severe AKI-3. Positive correlations were found between a-STI and the N-terminal brain natriuretic peptide precursor (NT-pro BNP) (ρ = 0.442, p < 0.001), the sequential organ failure assessment (SOFA) score (ρ: 0.361, p = 0.004), and baseline serum creatinine (ρ: 0.529, p < 0.001). Conclusions: Critically ill patients who developed AKI had statistically significant different a-STI (on admission to ICU), v-STI, and VII than those who did not. Moreover, a-STI was associated with the development of AKI at day 5 and provided the best diagnostic accuracy for the diagnosis of any AKI or severe AKI compared with RDRI, VII, and v-STI.

Characteristics of the Maternal Jugular Venous Pulse Waveform by Combined Doppler-Electrocardiogram Assessment.

Standardized combined Doppler-electrocardiogram assessment was performed longitudinally at three different locations of internal jugular veins between 12 wk of gestation and 6 wk postnatally in 24 uncomplicated pregnancies. All images were classified as typical or non-typical based on the presence of the physiologic deflections A, X, H and C. Linear mixed models with random intercepts of typical images were used to investigate gestational changes in venous pulse transit time and venous impedance index. Unequivocal identification of venous pulse transit time and venous impedance index was possible in 2617 of 3798 (69%) and 2234 of 3798 (59%) images, respectively. The best identification rate (80%, 1018/1266) was at the right distal internal jugular vein. Venous pulse transit time increased with gestational age at all locations; venous impedance index decreased at the right sided internal jugular vein. Maternal jugular venous pulse waveform by combined Doppler-electrocardiogram allows unequivocal identification of A-deflection and calculation of venous pulse transit time and venous impedance index in around two-thirds of assessments, with the highest success rate at the right distal internal jugular vein. Gestational evolutions of venous pulse transit time and venous impedance index are similar to those reported at the level of renal interlobar and hepatic veins.

Early-onset preeclampsia is characterised by an increased vascular tone in internal jugular veins.

Purpose: This study aimed to investigate Doppler characteristics of maternal internal jugular veins in uncomplicated pregnancies vs. those affected by hypertensive disorders. Materials and methods: Venous pulse transit time and venous impedance index were measured at three different locations (right proximal, right distal, left proximal) of internal jugular veins according to a standardised combined Doppler-Electrocardiogram protocol in five different groups of pregnant women: uncomplicated pregnancy, early-onset preeclampsia, late-onset preeclampsia, gestational hypertension, and normotensive pregnancies with a small for gestational age foetus. Values of both parameters of the latter four groups were plotted against the reference range of uncomplicated pregnancies at corresponding gestation. Linear mixed models with random intercept were used to investigate gestational changes in venous pulse transit time and venous impedance index at the three internal jugular vein locations within and between the different groups. Results: A total of 127 women were included: 41 had uncomplicated pregnancies, 13 had early-onset preeclampsia, 25 had late-onset preeclampsia, 22 had gestational hypertension, and 26 had normotensive pregnancies with a small for gestational age foetus. Venous pulse transit time values were lower than uncomplicated pregnancy (p ≤ 0.001) at all three locations in the third trimester of early-onset preeclampsia. Conclusion: Contrary to late-onset preeclampsia and gestational hypertension, early-onset preeclampsia is characterised by a lower venous pulse transit time at internal jugular veins compared to uncomplicated pregnancy, suggesting increased venous vascular tone.

Intrarenal Flow Alterations During Transition From Euvolemia to Intravascular Volume Expansion in Heart Failure Patients.

OBJECTIVES: The goal of this study was to assess: 1) the intrarenal flow in heart failure (HF) patients during the transition from euvolemia to intravascular volume overload; and 2) the relationship between intrarenal flow and diuretic efficiency. BACKGROUND: Intrarenal blood flow alterations may help to better understand impaired volume handling in HF. METHODS: Resistance index (RI) and venous impedance index (VII) were assessed in 6 healthy subjects, 40 euvolemic HF patients with reduced ejection fraction (HFrEF), and 10 HF patients with preserved ejection fraction (HFpEF). Assessments were performed by using Doppler ultrasonography at baseline, during 3 h of intravascular volume expansion with 1 l of hydroxyethyl starch 6%, and 1 h after the administration of a loop diuretic. Clinical parameters, echocardiography, and biochemistry were assessed. Urine output was collected after 3 and 24 h. RESULTS: In response to volume expansion, VII increased significantly in HFrEF patients (0.4 ± 0.3 to 0.7 ± 0.2; p < 0.001) and in HFpEF patients (0.4 ± 0.3 to 0.7 ± 0.2; p = 0.002) but not in healthy subjects (0.2 ± 0.2 to 0.3 ± 0.1; p = 0.622). This outcome was reversed after loop diuretic administration. In contrast, RI did not change significantly after volume expansion. Echocardiographic-estimated filling pressures did not change significantly. VII during volume expansion was significantly correlated with diuretic response in HF patients independent of baseline renal function (R2 = 0.35; p < 0.001). CONCLUSIONS: In HF patients, intravascular volume expansion resulted in significant blunting of venous flow before a significant increase in cardiac filling pressures could be demonstrated. The observed impaired renal venous flow is correlated with less diuretic efficiency. Intrarenal venous flow patterns may be of interest for evaluating renal congestion.