BACKGROUND: Renal artery stenosis (RAS) is always associated with abnormalities in renal microvascular perfusion (RMP). However, few imaging methods can simultaneously evaluate the degree of luminal stenosis and RMP. Thus, this study will aim to evaluate the feasibility of using contrast-enhanced ultrasound (CEUS) for assessing both RAS and RMP to achieve a one-stop assessment of patients with suspected renovascular hypertension. METHODS: This will be a single-center diagnostic study with a sample size of 440. Patients with chronic kidney disease (CKD) and suspected of having resistant hypertension will be eligible. Patients with Stages 1-3 CKD will undergo CEUS and computed tomography (CT) angiography (CTA). Values obtained by CEUS and CTA for diagnosing low-grade (lumen reduced by <60%) and high-grade (lumen reduced by ≥60%) RAS will be compared. Moreover, all patients will also undergo radionuclide imaging. The diagnostic value for RAS will be assessed by the receiver operating characteristic curve, including the accuracy, sensitivity, specificity, positive predictive values, negative predictive values, and area under the ROC. Pearson correlation analysis will be performed to assess the association between CEUS findings for RMP and glomerular filtration rate measured by a radionuclide imaging method. CONCLUSION: The data gathered from this study will be used to evaluate the feasibility of expanding clinical applications of CEUS for evaluation of patients with suspected renovascular hypertension. TRIAL REGISTRATION Chinese Clinical Trial Registry, ChiCTR1800016252; https://www.chictr.org.cn.
Contrast Media ; Glomerular Filtration Rate ; physiology ; Humans ; Hypertension, Renovascular ; physiopathology ; ROC Curve ; Renal Artery ; physiopathology ; Renal Artery Obstruction ; physiopathology

BACKGROUNDThe offspring of women with gestational diabetes mellitus (GDM) are prone to macrosomia. However, birth weight is difficult to be correctly estimated by ultrasound because of fetal asymmetric growth characteristics. This study aimed to investigate the correlations between fetal hemodynamics, fetal growth indices in late pregnancy, and birth weight in GDM.

METHODSA total of 147 women with GDM and 124 normal controls (NC) were enrolled in this study. Fetal hemodynamic indices, including the systolic/diastolic ratio (S/D), resistance index (RI), pulsatility index (PI) of umbilical artery (UA), middle cerebral artery (MCA), and renal artery (RA), were collected. Fetal growth indices, including biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length, were also measured by ultrasound. Birth weight, newborn gender, and maternal clinical data were collected.

RESULTSThe independent samples t-test showed that BPD, HC, and AC were larger in GDM than in NC (P < 0.05). Fetal hemodynamic indices of the UA and MCA were lower (P < 0.05), but those of the RA were higher (P < 0.001) in GDM than in NC. Birth weight was higher in GDM than in NC (P < 0.001). Pearson's correlation analysis showed that hemodynamic indices of the UA were negatively correlated with birth weight, BPD, HC, and AC in both groups (P < 0.05). MCA (S/D, PI, and RI) was negatively correlated with birth weight, HC, and AC in GDM (r = -0.164, -0.206, -0.200, -0.226, -0.189, -0.179, -0.196, -0.177, and - 0.172, respectively, P< 0.05), but there were no correlations in NC (P > 0.05). RA (S/D, PI, and RI) was positively correlated with birth weight in GDM (r = 0.168, 0.207, and 0.184, respectively, P< 0.05), but there were no correlations in NC (P > 0.05).

CONCLUSIONFetal hemodynamic indices in late pregnancy might be helpful for estimating newborn birth weight in women with GDM.

Adult ; Birth Weight ; physiology ; Cerebral Arteries ; physiology ; Diabetes, Gestational ; physiopathology ; Female ; Fetal Development ; physiology ; Hemodynamics ; physiology ; Humans ; Infant, Newborn ; Male ; Pregnancy ; Pregnancy Outcome ; Renal Artery ; physiology ; Ultrasonography, Prenatal ; Umbilical Arteries ; physiology

OBJECTIVETo investigate renal artery injury caused by Kawasaki disease (KD).

METHODSForty-three children with KD were enrolled in the study. According to the blood pressure in the acute stage, these children were classified into normal blood pressure subgroup and increased blood pressure subgroup. Eighteen children with fever caused by acute upper respiratory tract infection were enrolled as the control group. The diameter of the origin of the main renal artery, hemodynamic parameters of the main renal artery and the renal interlobar artery, rennin activity, and levels of angiotensin II and aldosterone were compared between groups.

RESULTSDuring the acute stage of KD, both subgroups had a significantly smaller diameter of the origin of the main renal artery, a significantly higher resistance index (RI) of the main renal artery, and a significantly lower end-diastolic velocity (EDV) than the control group (P<0.05).The increased blood pressure subgroup had a significantly lower EDV of the interlobar artery than the normal blood pressure subgroup, a significantly higher RI than the normal blood pressure subgroup and the control group, as well as a significantly higher rennin activity and significantly higher levels of angiotensin II and aldosterone than the normal blood pressure subgroup (P<0.05). A significantly increased EDV and a significantly reduced RI of the renal interlobar artery were observed in the increased blood pressure subgroup in the subacute stage compared with the acute stage (P<0.05).

CONCLUSIONSKD may cause renal artery injury and early hemodynamic changes, resulting in a transient increase in blood pressure in some patients.

Blood Flow Velocity ; Blood Pressure ; Child, Preschool ; Female ; Humans ; Infant ; Male ; Mucocutaneous Lymph Node Syndrome ; physiopathology ; Renal Artery ; physiopathology ; Renin-Angiotensin System ; physiology ; Vascular Resistance

OBJECTIVE: To determine whether an optimal blood suppression inversion time (BSP TI) can boost arterial visibility and whether the optimal BSP TI is related to breathing rate (BR) and heart rate (HR) for hypertension subjects in spatial labeling with multiple inversion pulses (SLEEK). MATERIALS AND METHODS: This prospective study included 10 volunteers and 93 consecutive hypertension patients who had undergone SLEEK at 1.5T MRI system. Firstly, suitable BSP TIs for displaying clearly renal artery were determined in 10 volunteers. Secondly, non-contrast enhanced magnetic resonance angiography with the suitable BSP TIs were performed on those hypertension patients. Then, renal artery was evaluated and an optimal BSP TI to increase arterial visibility was determined for each patient. Patients' BRs and HRs were recorded and their relationships with the optimal BSP TI were analyzed. RESULTS: The optimal BSP TI was negatively correlated with BR (r1 = -0.536, P1 < 0.001; and r2 = -0.535, P2 < 0.001) and HR (r1 = -0.432, P1 = 0.001; and r2 = -0.419, P2 = 0.001) for 2 readers (kappa = 0.93). For improving renal arterial visibility, BSP TI = 800 ms could be applied as the optimal BSP TI when the 95% confidence interval were 17-19/min (BR1) and 74-82 bpm (HR1) for reader#1 and 17-19/min (BR2) and 74-83 bpm (HR2) for reader#2; BSP TI = 1100 ms while 14-15/min (BR1, 2) and 71-76 bpm (HR1, 2) for both readers; and BSP TI = 1400 ms when 13-16/min (BR1) and 63-68 bpm (HR1) for reader#1 and 14-15/min (BR2) and 64-70 bpm (HR2) for reader#2. CONCLUSION: In SLEEK, BSP TI is affected by patients' BRs and HRs. Adopting the optimal BSP TI based on BR and HR can improve the renal arterial visibility and consequently the working efficiency.
Adult ; Female ; *Heart Rate ; Humans ; Hypertension/pathology ; Kidney/*blood supply ; Magnetic Resonance Angiography/*methods ; Male ; Middle Aged ; Prospective Studies ; Renal Artery/*physiology ; *Respiratory Rate

BACKGROUNDPrevious data are controversial about the association of renal artery stenosis (RAS) with clinical outcome in patients with heart failure. Definition of RAS in previous studies might not be appropriate. By definition of RAS with renal duplex sonography, we investigated the association of RAS with clinical outcome in patients with heart failure.

METHODSIn this retrospective study, we identified 164 patients with heart failure (New York Heart Association classification ≥II; left ventricular ejection fraction <50%) who had received renal duplex sonography during hospital stay. RAS was defined as renal-aortic ratio ≥3.5 or a peak systolic velocity ≥200 cm/s (or both), or occlusion of the renal artery. Categorical data of patients were compared using the Chi-square test or Fisher's exact test. Cox proportional hazards regression modeling technique was used to investigate the prognostic significance of possible predictors.

RESULTSFinally, 143 patients were enrolled. Median follow-up time was 32 months (1-53 months). Twenty-two patients were diagnosed as RAS by renal duplex sonography, including 13 unilateral RAS (3 left RAS, 10 right RAS) and 9 bilateral RAS. There were more all-cause mortality and cardiovascular death in patients with RAS than patients without RAS. By multivariate analysis, RAS was a significant predictor for all-cause death and cardiovascular death (hazard ratio [HR] = 4.155, 95% confidence interval [CI]: 1.546-11.164, P = 0.005; and HR = 3.483, 95% CI: 1.200-10.104, P = 0.022, respectively). As for composite endpoint events, including death, nonfatal myocardial infarction, ischemic stroke or intracranial hemorrhage, rehospitalization for cardiac failure, and renal replacement therapy, only angiotensin-converting enzyme inhibitor or angiotensin-receptor blocker was significant predictor. RAS was not a significant predictor for composite endpoint events.

CONCLUSIONSOur data suggested that RAS is associated with a poorer clinical outcome in patients with heart failure.

Aged ; Atherosclerosis ; diagnosis ; etiology ; mortality ; Chi-Square Distribution ; Heart Failure ; complications ; mortality ; Humans ; Middle Aged ; Renal Artery Obstruction ; diagnosis ; etiology ; mortality ; Retrospective Studies ; Stroke Volume ; physiology

BACKGROUNDThe decrease of glomerular filtration rate has been theoretically supposed to be the result of low perfusion in renal artery stenosis (RAS). But the gap between artery stenosis and the glomerular filtration ability is still unclear.

METHODSPatients with selective renal artery angiogram were divided by the degree of renal artery narrowing, level of estimated glomerular filtration rate (eGFR), respectively. The different levels of eGFR, renal microcirculation markers, and RAS severity were compared with each other, to determine the relationships among them.

RESULTSA total of 215 consecutive patients were enrolled in the prospective cohort study. Concentrations of microcirculation markers had no significant difference between RAS group (RAS ≥ 50%) and no RAS group (RAS < 50%) or did not change correspondingly to RAS severity. The value of eGFR in RAS group was lower than that in the no RAS group, but it did not decline parallel to the progressive severity of RAS. The microcirculation markers presented integral difference if grouped by different eGFR level with negative tendency, especially that plasma cystatin C (cysC) and urinary microalbumin to creatinine ratio (mACR) increased with the deterioration of eGFR, with strong (r = -0.713, P < 0.001) and moderate (r = -0.580, P < 0.001) correlations. In the subgroup analysis of severe RAS (RAS ≥ 80%), the levels of plasma cysC and urinary mACR demonstrated stronger negative associations with eGFR, (r = -0.827, P < 0.001) and (r = -0.672, P < 0.001) correlations, respectively.

CONCLUSIONSSeverity of RAS could not accurately predict the value of eGFR, whereas microcirculation impairment may substantially contribute to the glomerular filtration loss in patients with RAS.

Aged ; Female ; Glomerular Filtration Rate ; physiology ; Humans ; Male ; Microcirculation ; physiology ; Middle Aged ; Prospective Studies ; Renal Artery Obstruction ; physiopathology ; Retrospective Studies

Coronary Angiography ; Fractional Flow Reserve, Myocardial ; physiology ; Humans ; Renal Artery Obstruction ; physiopathology

PURPOSE: Coronary artery calcification (CAC) has been described in individuals with chronic kidney disease (CKD), and its presence is associated with an increased risk of cardiovascular death. However, it is unclear whether there is an independent relationship between renal function and CAC. Therefore, we evaluated the association between renal function and CAC. MATERIALS AND METHODS: We retrospectively reviewed 870 Korean patients who had undergone computed tomographic coronary angiography. The glomerular filtration rate (GFR) was estimated using the Modification of Diet in Renal Disease study formula with an ethnic factor for the Korean population. The CKD stages were classified using estimated GFR (eGFR) and proteinuria. RESULTS: The mean age of the participants was 56.8+/-11.8 years, and the mean eGFR was 89.4+/-16.5 mL/min/1.73 m2. Hypertension and diabetes were noted in 41.5 and 17.0% of patients, respectively. There were 584 and 286 patients with no CAC and with CAC, respectively. After adjusting for confounding variables, late stage CKD was associated with CAC [odds ratio (OR) 2.80, 95% confidence interval (CI) 1.05-7.46]. However, early stage CKD was not associated with CAC (OR 1.61, 95% CI 0.92-2.82). Diabetes was an independent risk factor of CAC (OR 2.06, 95% CI 1.36-3.13). There was no significant association between proteinuria and CAC (OR 1.65, 95% CI 0.96-2.85). CONCLUSION: CAC is related to late stage CKD in nondialyzed patients. These findings emphasize that individuals with CAC should be considered a high-risk population for decreased renal function.
Aged ; Chronic Disease ; Coronary Artery Disease/*pathology/*physiopathology ; Female ; Glomerular Filtration Rate/physiology ; Humans ; Kidney Diseases/pathology/*physiopathology ; Linear Models ; Male ; Middle Aged ; Proteinuria/pathology/physiopathology ; Renal Dialysis ; Retrospective Studies ; Risk Factors

OBJECTIVETo evaluate whether taking atorvastatin for long time has positive effects on age-related renal impairment.

METHODS20-month-age normal female Wistar rats were divided into three groups (n = 9). First group were fed atorvastatin 10 mg/(kg x d). Second group were fed atorvastatin 1 mg/(kg x d). Third group were fed the same volume normal saline served as control. All the rats were sacrificed after four months. 3-month-age normal female Wistar rats (n = 9) also served as normal control. Kidney weight, serum creatinine (Scr) and blood-lipoids were measured. Paraffin sections of renal tissues were stained with PAS and Sirius red. Sclerosis index of glomerulus was calculated.

RESULTSRenal mass diminution was found in all the groups of aging rats. Scr was decreased in the group of aging rats with atorvastatin 1 mg/(kg x d). The level of blood-lipoids of aging rats was higher than that of young rats. The level of serum cholesterol and low-density lipoprotein (LDL) were decreased in first group (both P < 0.05) and only LDL decreased in second group (P < 0.05). Morphological changes of aging kidney were focal segmental glomerulosclerosis, widen of mesangial region, infiltration of inflammatory cells and sclerosis of arteriole. The treatment of atorvastatin improved the pathologic changes in the aging rats significantly, especially in the first group.

CONCLUSIONTaking atorvastatin for long time can notably improve the pathological changes of aging kidney. All these effects may be induced by lowing of blood-lipoids, relieving the sclerosis of renal arteriole and reducing the infiltration of inflammatory cells.

Aging ; physiology ; Animals ; Anticholesteremic Agents ; administration & dosage ; pharmacology ; Arteriosclerosis ; pathology ; prevention & control ; Atorvastatin Calcium ; Female ; Heptanoic Acids ; administration & dosage ; pharmacology ; Kidney ; pathology ; Kidney Diseases ; prevention & control ; Pyrroles ; administration & dosage ; pharmacology ; Rats ; Rats, Wistar ; Renal Artery ; pathology

The present study was designed to investigate the effects of high-saturated and high-unsaturated fatty acid diets on relaxation and contraction of the renal arteries in insulin resistance (IR) rats. Wistar rats were fed normal chow diet (control), high-saturated fatty acid diet or high-unsaturated fatty acid diet for 6 months (n=14 in each group). IR was evaluated by glucose infusion rate (GIR) of hyperinsulinemic euglycemic clamp. Blood pressure was measured via the tail-cuff method. Body weight (BW), plasma total triglyceride (TG), free fatty acid (FFA), insulin, fasting blood glucose (FBG) and nitric oxide metabolite (NO2(-)/NO3(-)) were compared among the three groups. The rats were sacrificed and the renal arterial rings were placed in the physiological tissue baths for measurement of vascular response to various agents. After the arterial rings were constricted with 3 mmol/L noradrenaline (NA), endothelium-dependent vasorelaxation to acetylcholine (ACh) and endothelium-independent vasorelaxation to sodium nitroprusside (NTP) were measured. Endothelium-dependent vasorelaxation to ACh was also observed in renal arterial rings incubated with L-arginine (L-Arg), N(omega)-nitro-L-arginine (L-NNA) and methylene blue (MB), respectively. Arterial contractility was evaluated from concentration-response curves to 10 nmol/L-100 micromol/L NA. Saturated or unsaturated fatty acids led to moderate rises in blood pressure (P<0.05). It was associated with higher levels of plasma lipids and lower whole body insulin sensitivity (P<0.01). There were no significant differences in BW, FBG, TG, insulin and FFA between saturated and unsaturated fatty acid-fed rats. A decrease in endothelium-dependent vasorelaxation of the renal arteries in saturated and unsaturated fatty acid-fed rats was observed (P<0.01), but there was no marked difference between the two high-fatty acid diet groups. Endothelium-dependent vasorelaxation was increased when the arteries were incubated with L-Arg and decreased when incubated with L-NNA and MB in both high-fatty acid diet groups (P<0.05, P<0.01). But no difference was found before and after incubation with L-Arg, L-NNA and MB in the control rats. In the mean time, endothelium-independent maximal vasorelaxation response of renal arteries to NTP and renal arterial contractile responses to cumulative dose of NA were assayed, and there was no difference among the three groups (P>0.05). Endothelium-dependent vasorelaxation was negatively correlated with systolic blood pressure and TG, and positively correlated with NO2(-)/NO3(-) and GIR. There was a significantly negative correlation between FFA and NO2(-)/NO3(-). The present study suggests that both high-saturated and unsaturated fatty acid diets result in hypertension associated with significantly decreased endothelium-dependent vasorelaxation, dyslipidemia and IR, and that decreased endothelium-dependent vasorelaxation induced by high fatty acid diets is associated with impaired L-Arg-NO-cGMP pathways.
Animals ; Dietary Fats, Unsaturated ; administration & dosage ; Endothelium, Vascular ; physiology ; Fatty Acids ; administration & dosage ; Insulin Resistance ; Male ; Nitric Oxide ; physiology ; Rats ; Rats, Wistar ; Renal Artery ; physiology ; Systole ; Vasoconstriction ; Vasodilation