Increased renal cortical stiffness obtained by share-wave elastography imaging significantly predicts the contrast-induced nephropathy in patients with preserved renal function

The application of shear wave quantitative ultrasound elastography in chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is a major public health problem, so it is particularly important to quantitatively assess and intervene in the degree of early renal damage in CKD.

OBJECTIVE

The objective of the research is to establish reference values for kidney elasticity by using real-time shear wave elastography (RT-SWE) technology to quantify Young's modulus values in the renal cortex of normal adults. The intention is to provide a foundation for evaluating renal function and structural changes in patients with CKD. Furthermore, this research investigates the role of RT-SWE in the early detection of renal fibrosis in CKD, providing insights into its diagnostic value for detecting pathological changes at an early stage.

METHODS

Between August 2019 and December 2021, we collected a sample of 100 healthy people (55 men with an average age of 43.5 ± 15.2 years and 45 women with an average age of 41.6 ± 19.8 years) for medical evaluations at our hospital's Department of Ultrasound Medicine. In addition, 97 individuals with CKD1-3 stage were considered. Following the removal of contraindications and relevant confounding variables, we included a final cohort of 80 individuals in the research (45 men and 35 females, with an average age of 39.1 ± 19.2 years). The RENAL mode was selected and a convex array probe S6-1 operating at a frequency of 3.5-5.5 MHz was used in the research, which made use of the French Supersonic AixPlorer ultrasonic diagnostic instrument. Renal RT-SWE elastography was performed after conventional two-dimensional and color Doppler ultrasonography. The study used RT-SWE technology to assess the mean Young's modulus of the cortex in healthy individuals (Emean), with data analysis and comparisons based on age and gender. Furthermore, the Emean values of CKD stage 1-3 patients were determined, and analyses were performed about 24-hour urine protein quantitative (24hUTP), serum creatinine concentration (SCr), and renal biopsy pathology, specifically the degree of interstitial fibrosis.

RESULTS

Healthy group: a) The average kPa values of the left kidney (4.2 ± 2.3), right kidney (4.3 + 2.5) kPa, both kidneys' average kPa values (4.3 ± 2.4) kPa, and the average kPa values of the left and right kidneys do not differ statistically (p= 0.986). b) There was no difference in the kPa values of healthy male and female kidneys (4.4 + 2.1 and 4.2 + 2.6, respectively. c) There was no difference in the renal kPa values of healthy adults aged 50 (4.4 ± 2.8) kPa and renal kPa of the 50-year-old population (4.2 + 2.1) kPa (p= 0.041). Case group: a) the group of patients with CKD1-3 stage and the group did not vary in their Emean values (both p< 0.05); b) There is a difference between CKD stages 1, 2, and 3 (p< 0.05), however, there is still no difference in the pyEmean value corrected for patient age between patients in stages 1 and 2 (p> 0.05).

CONCLUSION

The study reveals no significant differences in the Emean value of bilateral kidneys in normal people and no differences in the elasticity value of kidneys and gender. However, age-based differences were statistically significant. pyEmean may be useful for comparing CKD stage 1, 2, and 3 patients, and RT-SWE can assess early renal damage.

Ultrasound elastography in chronic kidney disease: a systematic review and meta-analysis

Ultrasound elastography (USE) is a noninvasive technique for assessing tissue elasticity, and its application in nephrology has aroused growing interest in recent years. The purpose of this article is to systematically review the clinical application of USE in patients with chronic kidney disease (CKD), including native and transplanted kidneys, and quantitatively investigate differences in elasticity values between healthy individuals and CKD patients. Furthermore, we provide a qualitative analysis of the studies included, discussing the potential interplay between renal stiffness, estimated glomerular filtration rate, and fibrosis. In January 2022, a systematic search was carried out on the MEDLINE (PubMed) database, concerning studies on the application of USE in patients with CKD, including patients with transplanted kidneys. The results of the included studies were extracted by two independent researchers and presented mainly through a formal narrative summary. A meta-analysis of nine study parts from six studies was performed. A total of 647 studies were screened for eligibility and, after applying the exclusion and inclusion criteria, 69 studies were included, for a total of 6728 patients. The studies proved very heterogeneous in terms of design and results. The shear wave velocity difference of - 0.82 m/s (95% CI: - 1.72-0.07) between CKD patients and controls was not significant. This result agrees with the qualitative evaluation of included studies that found controversial results for the relationship between renal stiffness and glomerular filtration rate. On the contrary, a clear relationship seems to emerge between USE values and the degree of fibrosis. At present, due to the heterogeneity of results and technical challenges, large-scale application in the monitoring of CKD patients remains controversial.

Accuracy Rate of Shear Wave Elastography in Detecting the Liver Fibrosis in Overweight and Obese Children with Hepatosteatosis

OBJECTIVE

The aim of this study was to compare the accuracy rate of liver stiffness calculated by shear wave elastography with liver biopsy results in obese and overweight children.

MATERIALS AND METHODS

Obese and overweight children between 3 and 18 years of age, who had hepatic steatosis and a healthy control group were included in this study. A blood sample was obtained for laboratory tests and shear wave elastography was performed for all subjects. Liver biopsies were performed only in patients with hepatosteatosis, providing permission for biopsy, and for whom the biopsy procedure was not contraindicated.

RESULTS

A cohort of 142 children (78 overweight/obese and 64 healthy) was included in this study. Shear wave elastography values were significantly higher in the patient group as com- pared to the control group (34.0 vs. 8.2 kPa; P < .001). Obese children had higher elastog- raphy values compared to non-obese children (50.2 vs. 23.7 kPa, P < .001). No correlation was detected between fibrosis score and elastography values. Elastography increased with increasing weight (correlation coefficient: 0.334, P = .003) and body mass index (correlation coefficient: 0.364, P = .001).

CONCLUSION

In obese and overweight patients, elastography values are higher than in healthy subjects as well as patients with liver fibrosis. Disease-specific cut-off, mean, and normal ref- erence range values should be defined with large-scale studies to improve interpretation of elastography values. Our results are contradictory in the determination of liver fibrosis with shear wave elastography in obese and overweight patients, thus further research with a larger patient population is recommended.

Left-ventricular outflow tract acceleration time is associated with symptoms in patients with obstructive hypertrophic cardiomyopathy

Aims

Not all obstructive hypertrophic cardiomyopathy (HCM) patients are symptomatic. The relation between obstructive HCM and symptoms is not well understood. The hypothesis of this study is that left-ventricular outflow tract (LVOT) acceleration time (AT) is associated with symptoms.

Methods

We included 187 patients (61% men, mean age 55 ± 14 years) with obstructive HCM, defined as a maximal wall thickness ≥ 15 mm and a resting or provoked LVOT peak gradient ≥ 30 mmHg. Peak velocity (PV), left-ventricular (LV) ejection time (ET), and AT (the time between LVOT flow onset and the moment of PV) were measured on continuous-wave (CW) Doppler tracings. Logistic and Cox proportional hazard regression analyses were used to evaluate the relation between symptoms [New York Heart Association (NYHA) class ≥ II] and echocardiographic measurements, including AT. Reproducibility was assessed using the intraclass correlation coefficient (ICC).

Results

Symptomatic patients were more often female and had higher mean AT values. Logistic regression demonstrated a significant association between AT and symptomatic status (odds ratio 1.31 per 10 ms, p < 0.01) after adjustment for sex, negative inotropes, PV, LVOT diameter, and diastolic dysfunction. AT was independently associated with symptoms and septal reduction during follow-up (hazard ratio 1.09 per 10 ms, p < 0.05). The ICC was 0.98 with a mean difference of 0.28 ± 8.4 ms.

Conclusion

In obstructive HCM patients, increased AT is significantly related to symptoms after adjustment for sex, negative inotropes, PV, LVOT diameter, and diastolic dysfunction, and is associated with the symptomatic status during follow-up. AT represents an easily measured echocardiographic variable with excellent inter-reader reproducibility.

Electronic supplementary material

The online version of this article (10.1007/s40477-020-00513-3) contains supplementary material, which is available to authorized users.

Carotid-femoral pulse wave velocity is significantly increased in newly diagnosed hypertensive patients with primary hyperparathyroidism and significantly related with serum calcium level

BACKGROUND

Primary hyperparathyroidism (PHP) is a rare cause of secondary hypertension (HT), but in patients with PHP, HT is very common and 20-80% of patients have HT. The aim of this study was to evaluate the change in carotid-femoral pulse wave velocity (CF-PWV) in hypertensive patients with PHP, and was to determine the clinical, laboratory, and echocardiographic parameters associated with CF-PWV.

METHODS

The study included 83 newly diagnosed hypertensive patients with PHP and 83 patients with newly diagnosed essential HT without PHP. All patients underwent echocardiography and CF-PWV measurements.

RESULTS

In patients with PHP, blood urea nitrogen, hs-CRP, uric acid, serum and urine calcium, parathyroid hormone level, CF-PWV value, LV wall thickness, LVMI, aortic and left atrium (LA) diameter, and presence of LVH and CF-PWV > 10 m/s were higher, and serum phosphorus levels were lower. Serum calcium, LA diameter, and LVMI values were closely correlated with CF-PWV. In the ROC analysis, the AUROC was calculated as 0.825 for calcium level to determine the patients with increased CF-PWV. When the serum calcium value was taken as 10 mg/dL, it was determined with CF-PWV > 10 m/s were 79.5% sensitivity and 78.2% specificity.

CONCLUSION

CF-PWV significantly increases in newly diagnosed hypertensive patients with PHP and significantly related to serum calcium level. To protect against target organ damage, high serum calcium levels should be monitored as well as blood pressure in hypertensive patients with PHP.

Residual SYNTAX Score Is Associated With Contrast-Induced Nephropathy in Patients With Non-ST Segment Elevation Myocardial Infarction With Preserved LVEF

The purpose of this study is to investigate the relation between residual SYNTAX score (rSS) and contrast-induced nephropathy (CIN) development in patients with non-ST segment elevation myocardial infarction (NSTEMI) with normal or near-to-normal left ventricular ejection fraction (LVEF) who underwent percutaneous coronary intervention (PCI). A total of 306 patients who underwent PCI with NSTEMI were included in our study. SYNTAX scores were calculated for the periods before and after PCI. Patients were divided into 2 groups as developed CIN following PCI (CIN +) and patients did not (CIN -). Fifty-four (17.6%) of patients who were included in the study developed CIN. Age (P = .001) and rSS (P = .002) were significantly higher and LVEF was lower (P = .034) in the CIN (+) group. Age (P = .031, odds ratio [OR]: 1.031, 95% CI, 1.003-1.059) and rSS (P = .04, OR: 1.036, 95% CI, 1.002-1.071) were independent predictors for CIN. In receiver operating characteristic analyses, when the cutoff value of rSS was taken as 3.5, it determined CIN with 79% sensitivity and 65% specificity. Contrast-induced nephropathy may develop more frequently in patients with increased rSS value. The rSS may be useful to follow-up these patients for CIN development.

Is High Preprocedural Renal Resistive Index Sensitive Enough to Predict Iodine Contrast-Induced Nephropathy in Patients Receiving Intra-Arterial Iodinate Contrast?

PURPOSE

Renal Resistive Index (RRI) is a newly introduced sonographic index in predicting contrast-induced nephropathy (CIN) development. It has been suggested that RRI > 0.69 should be considered as a risk factor for CIN development. The present study aimed to calculate the predictive value of RRI using a cutoff point of 0.69.

METHODS

A total of 90 patients who were a candidate for coronary vessels angiography were enrolled in this study. Color Doppler ultrasonography was performed and RRI was measured. Patients were followed up for 48 hours after contrast media exposure for the CIN development. The diagnosis of CIN was based on a 25% relative rise or 0.5 mg/dL absolute rise in creatinine level. The predictive values of RRI were measured using 0.69 as a cutoff point.

RESULTS

Out of 90 patients, CIN developed in 3 patients and 17 patients had preprocedural RRI > 0.69. Of 3 patients with CIN, 1 had RRI > 0.69. Using 0.69 as the cutoff point, the measured sensitivity and specificity of RRI were 33.3% and 83.9%, respectively.

CONCLUSIONS

RRI > 0.69 is not a sensitive index in predicting the CIN development and cannot be used as an independent factor.