Subclinical Abnormalities of Left Ventricular Myocardial Deformation in Early-Stage Chronic Kidney Disease: The Precursor of Uremic Cardiomyopathy?

Hypertension and Left Ventricular Strain in Pediatric Chronic Kidney Disease

BACKGROUND

Left ventricular global longitudinal strain (LV GLS) on echocardiography is a sensitive yet clinically significant marker of myocardial dysfunction. Reduced LV GLS is prevalent in adults with chronic kidney disease and hypertension and is associated with adverse cardiovascular outcomes. It may be a biomarker of chronic kidney disease-associated myocardial dysfunction in children, but data are limited. Our objective was to describe LV GLS in the CKiD study (Chronic Kidney Disease in Children) and to examine the association between blood pressure (BP) and reduced LV GLS.

METHODS

A single apical 4-chamber view was used to estimate LV GLS. Our main analyses examined the association of clinic BP with the absolute value of LV GLS and LV GLS dichotomized at 16. Sensitivity analyses using 24-hour ambulatory BP monitoring data were also performed. Generalized estimating equations were used to account for within-person correlation and to estimate robust SEs for 95% CIs. Covariates in adjusted models included: age, sex, race, estimated glomerular filtration rate, urine protein, hemoglobin, left ventricular hypertrophy, and the use of renin-angiotensin system inhibitors.

RESULTS

LV GLS was measured in 962 person-visits. A total of 77 assessments had an LV GLS <16. In adjusted models, both clinic systolic BP (odds ratio, 1.02 [95% CI, 1.01-1.03]) and diastolic BP (odds ratio, 1.02 [95% CI, 1.00-1.03]) percentiles were associated with LV GLS <16. Having awake or nighttime diastolic BP hypertension on ambulatory BP monitoring was significantly associated with a lower absolute value of LV GLS.

CONCLUSIONS

Office systolic and diastolic hypertension was associated with diminished LV GLS. Only diastolic hypertension detected on ambulatory BP monitoring was associated with lower LV GLS.

A Machine Learning-Derived Score to Effectively Identify Heart Failure With Preserved Ejection Fraction

Background

The diagnosis of heart failure with preserved ejection fraction (HFpEF) in the clinical setting remains challenging, especially in patients with obesity.

Objectives

This study aimed to identify novel predictors of HFpEF well suited for patients with obesity.

Methods

We performed a retrospective analysis of a well-characterized cohort of patients with obesity with HFpEF (n = 404; mean body mass index [BMI] 36.6 kg/m2) and controls (n = 67). We used the machine learning algorithm Gradient Boosting Machine to analyze the association of various parameters with the diagnosis of HFpEF and subsequently created a multivariate logistic model for the diagnosis.

Results

Gradient Boosting Machine identified BMI, estimated glomerular filtration rate, left ventricular mass index, and left atrial to left ventricular volume ratio as the strongest predictors of HFpEF. These variables were used to build a model that identified HFpEF with a sensitivity of 0.83, a specificity of 0.82, and an area under the curve (AUC) of 0.88. Internal validation of the model with optimism-adjusted AUC showed an AUC of 0.87. Within the studied cohort, the novel score outperformed the H2FPEF score (AUC: 0.88 vs 0.74; P < 0.001).

Conclusions

In a HFpEF cohort with obesity, BMI, estimated glomerular filtration rate, left ventricular mass index, and left atrial to left ventricular volume ratio most correlated with the identification of HFpEF, and a score based on these variables (HFpEF-JH score) outperformed the currently used H2PEF score. Further validation of this novel score is warranted, as it may facilitate improved diagnostic accuracy of HFpEF, particularly in patients with obesity.

Early detection of myocardial involvement by non-contrast T1ρ mapping of cardiac magnetic resonance in type 2 diabetes mellitus

Objective

This study aims to determine the effectiveness of T1ρ in detecting myocardial fibrosis in type 2 diabetes mellitus (T2DM) patients by comparing with native T1 and extracellular volume (ECV) fraction.

Methods

T2DM patients (n = 35) and healthy controls (n = 30) underwent cardiac magnetic resonance. ECV, T1ρ, native T1, and global longitudinal strain (GLS) values were assessed. Diagnostic performance was analyzed using receiver operating curves.

Results

The global ECV and T1ρ of T2DM group (ECV = 32.1 ± 3.2%, T1ρ = 51.6 ± 3.8 msec) were significantly higher than those of controls (ECV = 26.2 ± 1.6%, T1ρ = 46.8 ± 2.0 msec) (all P < 0.001), whether there was no significant difference in native T1 between T2DM and controls (P = 0.264). The GLS decreased significantly in T2DM patients compared with controls (-16.5 ± 2.4% vs. -18.3 ± 2.6%, P = 0.015). The T1ρ and native T1 were associated with ECV (Pearson's r = 0.50 and 0.25, respectively, both P < 0.001); the native T1, T1ρ, and ECV were associated with hemoglobin A1c (Pearson's r = 0.41, 0.52, and 0.61, respectively, all P < 0.05); and the ECV was associated with diabetes duration (Pearson's r = 0.41, P = 0.016). The AUC of ECV, T1ρ, GLS, and native T1 were 0.869, 0.810, 0.659, and 0.524, respectively.

Conclusion

In T2DM patients, T1ρ may be a new non-contrast cardiac magnetic resonance technique for identifying myocardial diffuse fibrosis, and T1ρ may be more sensitive than native T1 in the detection of myocardial diffuse fibrosis.

Effect of etelcalcetide versus alfacalcidol on left ventricular function and feature-tracking cardiac magnetic resonance imaging in hemodialysis-a post-hoc analysis of a randomized, controlled trial

BACKGROUND

Calcimimetic therapy with etelcalcetide (ETEL) has been shown to attenuate the advancement of left ventricular (LV) hypertrophy in hemodialysis patients measured by cardiac magnetic resonance (CMR). The aim of the study was to evaluate whether this effect is accompanied by alterations in LV function and myocardial composition.

METHODS

This was a post-hoc analysis of a randomized-controlled trial of ETEL versus Alfacalcidol (ALFA) in 62 hemodialysis patients. LV function was assessed using LV ejection fraction (LVEF) and LV global longitudinal strain (GLS) on feature-tracking (FT) CMR. Myocardial tissue characteristics were analyzed using parametric T1 and T2 mapping.

RESULTS

Of the total study cohort (n = 62), 48 subjects completed both CMR scans with sufficient quality for FT analysis. In the one-year follow-up, LV GLS deteriorated in the ALFA group, whereas the ETEL group remained stable (LV GLS change: + 2.6 ± 4.6 versus + 0.3 ± 3.8; p = 0.045 when adjusting for randomization factors and baseline LV GLS). We did not observe a difference in the change of LVEF between the two groups (p = 0.513). The impact of ETEL treatment on LV GLS over time remained significant after additional adjustment for the change in LV mass during the study period. ETEL treatment did not significantly affect other CMR parameters. There were no changes in myocardial composition between treatment groups (T1 time change: + 15 ± 42 versus + 10 ± 50; p = 0.411; T2 time change: - 0.13 ± 2.45 versus - 0.70 ± 2.43; p = 0.652).

CONCLUSIONS

In patients undergoing hemodialysis, treatment with ETEL was protective against deterioration of LV longitudinal function, as evaluated through FT CMR, when compared to the control therapy of ALFA. This effect was not mediated by the change in LV mass. Trial registration URL: https://clinicaltrials.gov/ct2/show/NCT03182699 . Unique identifier: NCT03182699.

Left Ventricular Function in Patients on Maintenance Hemodialysis: A Three-Dimensional Speckle-Tracking Imaging Study

INTRODUCTION

Although maintenance hemodialysis (MHD) in end-stage renal disease (ESRD) appears to induce some risk factors and strengthen cardiac function, the morbidity of ESRD patients receiving hemodialysis remains high. This study aimed to identify left ventricular (LV) structural and functional abnormalities in ESRD patients on MHD using three-dimensional speckle-tracking imaging (3D-STI).

METHODS

Eighty-five ESRD patients with normal LV ejection fraction (LVEF >50%) participated in this study, including 55 MHD patients comprising the chronic kidney disease (CKD) V-D group and 30 nondialysis patients comprising the CKD V-ND group. Thirty age- and sex-matched control participants who had normal kidney function were enrolled as the N group. Conventional echocardiography and 3D-STI were conducted, and global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) values were measured.

RESULTS

No substantial differences in two-dimensional LVEF were observed among the three groups, and LV hypertrophy was the most common abnormality in patients with ESRD, irrespective of whether they had received or not received MHD. There were no significant differences in the 3D LV mass index between the CKD V-ND and N groups (p > 0.05). Conversely, the 3D LV mass index was considerably higher in the CKD V-D group than in both the N and CKD V-ND groups. The GLS, GAS, and GRS values were significantly lower in the CKD V-ND group than in the N group (p < 0.05). Furthermore, the CKD V-D group had significantly lower GLS, GCS, GAS, and GRS values than the N and CKD V-ND groups (p < 0.05). The interventricular septal thickness and E/e' ratio were independently associated with LV strain values in all patients with ESRD.

CONCLUSIONS

MHD can exacerbate LV deformation and dysfunction in ESRD patients with preserved LVEF, and 3D-STI can be potentially useful for detecting these asymptomatic preclinical abnormalities.

Cardiovascular Alterations and Structural Changes in the Setting of Chronic Kidney Disease: a Review of Cardiorenal Syndrome Type 4

Cardiovascular and renal physiology are interrelated. More than a decade ago this was codified in guidelines defining the five subtypes of the cardiorenal syndrome. Morbidity and mortality for those with the cardiorenal syndrome is high compared to demographically matched individuals without cardiorenal disease, acute or chronic. The focus of this review will be the epidemiology, the impact of chronic kidney disease on cardiac structure and function, and associated clinical symptoms, outcomes, and potential treatments for patients with chronic reno-cardiac syndrome, or cardiorenal syndrome type 4. Cardiac structural changes can be profound and are described in detail both at a cellular and physiologic level. Integrating therapies for the treatment of causative or resulting comorbidities may ultimately slow progression of both cardiac and renal disease as well as minimize symptoms and death.

Associations between Albuminuria, Estimated GFR and Cardiac Phenotype in a Cohort with Chronic Kidney Disease - The CPH-CKD ECHO Study

OBJECTIVE

Echocardiographic findings in chronic kidney disease (CKD) vary. We sought to estimate the prevalence of abnormal cardiac structure and function in patients with CKD and their association to estimated glomerular filtration rate (eGFR) and urine albumin/creatinine ratio (UACR).

METHODS

We prospectively enrolled 825 outpatients with non-dialysis-dependent CKD, mean age 58± 13 yrs, and 175 matched healthy controls, mean age 60±12 yrs. Echocardiography included assessment of left ventricular (LV) hypertrophy, LV ejection fraction (LVEF), global longitudinal strain (GLS) and diastolic dysfunction according to ASE/EACVI guidelines.

RESULTS

LV hypertrophy was found in 9% of patients vs. 1.7% of controls (p=0.005) was independently associated with UACR (p=0.002). Median LVEF was 59.4% (IQR 55.2, 62.8) in patients vs. 60.8% (57.7, 64.1) in controls (p=0.002). GLS was decreased in patients with eGFR <60ml/min/1.73m² (-17.6%±3.1%) vs. patients with higher eGFR (19.0%±2.2%, p<0.001), who were similar to controls. . Diastolic dysfunction was detected in 55% of patients and in 34% of controls.

LIMITATIONS

Non-random sampling, cross-sectional analysis.

CONCLUSIONS

We report lower prevalence of hypertrophy than previous studies, but similar measurements of systolic and diastolic function. Cardiac remodeling in CKD may be influenced by treatment modalities, demographics, comorbidities and renal pathology.

Prognostic implications of traditional and non-traditional cardiovascular risk factor profiles in patients with non-valvular atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is a prevalent disease with associated mortality risk, mediated in large part through its associated cardiovascular risk factors. Standard modifiable cardiovascular risk factors (SMuRFs; hypercholesterolaemia, hypertension, diabetes and smoking) are established drivers of cardiovascular disease; however, the importance of non-traditional mediators of cardiovascular risk (NTRFs) such as chronic renal impairment, obstructive sleep apnoea and obesity is emerging. The differential impact of these risk factors on outcomes in patients with AF is not well studied.

METHODS

Consecutive patients admitted to our service between January 2013 and January 2018 with a primary diagnosis of non-valvular AF were assessed. Assessment of demographic, anthropometric, risk factor profile and pharmacotherapeutics was performed. The clinical course of these patients was followed for up to five years for the composite outcome of all-cause death and major adverse cardiovascular events.

RESULTS

Of the 1010 patients (62.29 ± 16.81 years, 51% men) included, 154 (15%) had no risk factors, 478 (47%) had only SMuRFs, 59 (6%) had only NTRFs and 319 (32%) had both SMuRFs and NTRFs. Over a mean follow-up period of 33.18 ± 21.27 months, a total of 288 patients met the composite outcome. On Cox regression, the coexistence of SMuRFs and NTRFs was an independent predictor of the composite outcome (HR 1.40; 95%CI 1.09-1.82, p = .01). Other independent predictors included age, heart failure, CHA₂ DS₂ VASc score, persistent AF and anaemia.

CONCLUSIONS

The presence of both SMuRFs and NTRFs has prognostic implications in patients with non-valvular AF.

The Diabetic Cardiorenal Nexus

The end-stage of the clinical combination of heart failure and kidney disease has become known as cardiorenal syndrome. Adverse consequences related to diabetes, hyperlipidemia, obesity, hypertension and renal impairment on cardiovascular function, morbidity and mortality are well known. Guidelines for the treatment of these risk factors have led to the improved prognosis of patients with coronary artery disease and reduced ejection fraction. Heart failure hospital admissions and readmission often occur, however, in the presence of metabolic, renal dysfunction and relatively preserved systolic function. In this domain, few advances have been described. Diabetes, kidney and cardiac dysfunction act synergistically to magnify healthcare costs. Current therapy relies on improving hemodynamic factors destructive to both the heart and kidney. We consider that additional hemodynamic solutions may be limited without the use of animal models focusing on the cardiomyocyte, nephron and extracellular matrices. We review herein potential common pathophysiologic targets for treatment to prevent and ameliorate this syndrome.

Evaluation of Asymmetric Dimethylarginine Serum Level and Left Ventricular Function by 2D Speckle Tracking Echocardiography in Children on Regular Hemodialysis

Cardiovascular disease is the leading cause of morbidity and mortality in children with chronic kidney disease. Asymmetric dimethylarginine (ADMA) is thought to be related to chronic kidney disease patients' adverse cardiovascular effects. Our study is to assess ADMA concentrations in children on hemodialysis (HD) as a marker of cardiovascular risk and detect the relation to the left ventricular (LV) function by traditional and speckled tracking echo. Forty children with end-stage renal disease on regular HD were enrolled in the study and selected from the nephrology HD unit of Al-Zahraa Hospital, Al-Azhar University. Another group of 40 healthy children matches age and sex with the patient's group as a control. ADMA serum level, traditional echo, and tissue Doppler imaging spackled tracking were performed to assess: LV functions for both groups in the same line with the routine laboratory investigations. Moreover, bioimpedance was assessed after the HD session. Children on regular HD have a significantly higher (ADMA) serum level compared to their controls; the median is (72.5 ng/mL) and (25 ng/mL), respectively (P = 0.001) and a significant increase in high-sensitivity C-reactive protein and the median is (3.6 ng/mL) and (2.5 ng/mL), respectively (P = 0.001). Moreover, conventional echo detects 27 (67.5%) patients out of 40 had an impaired LV function; meanwhile, 33 (82.5%) had a global LV strain (LV GLS) detected by 2D (Speckle echo), a negative correlation between LV ejection fraction with serum (urea, cholesterol, and triglyceride) and a positive correlation between ADMA and LV systolic diameter. LV GLS (Speckle echo) is negatively correlated with LV end-diastolic diameter, LV end-systolic diameter and positively correlated with LV inter ventricular septum in diastole and reduced average systolic velocity (ml). The sensitivity and specificity of (ADMA), high-sensitivity C-reactive protein (hs-CRP), traditional, and Speckle echo for early left ventricular (LV) dysfunction were 92.50, 92, and 67.50, 97 and 67.50, 90.00, and 80.00, 92, respectively. An ADMA emerges as a sensitive and specific marker for early LV dysfunction in children on hemodialysis (HD); drugs targeting ADMA isessential in the future direction after clinical approval, to avoid early LV changes, furthermore (Speckle echo) is superior to the traditional echo for early detection of LV changes in chronic kidney disease (CKD) children.

Left ventricular contractile reserve as a determinant of adverse clinical outcomes: a systematic review

An abnormal left ventricular contractile reserve is often seen in patients undergoing stress echocardiogram and may indicate the presence of obstructive coronary artery disease. The techniques and indexes used to identify abnormal left ventricular contractile response and its prognostic value in the absence of known causes has not been well studied. To describe the characteristics and clinical outcomes associated with an abnormal left ventricular contractile response, we performed a systematic review that identified 27 eligible studies. A diverse range of indices were utilised to measure left ventricular contractile reserve, most commonly Δleft ventricular ejection fraction in 11 studies. Dobutamine stress echocardiogram was the most commonly performed modality (19 studies) followed by exercise stress echocardiogram (4 studies), dipyridamole stress echocardiogram (2 studies), invasive hemodynamic measurement (1 study) and dobutamine stress magnetic resonance imaging (1 study). All but one study demonstrated a significant association between the absence of left ventricular contractile reserve and increased rate of cardiovascular events, cardiac death and all-cause mortality.

Risk for subsequent hypertension and cardiovascular disease after living kidney donation: is it clinically relevant?

The first successful live donor kidney transplant was performed in 1954. Receiving a kidney transplant from a live kidney donor remains the best option for increasing both life expectancy and quality of life in patients with end-stage kidney disease. However, ever since 1954, there have been multiple questions raised on the ethics of live kidney donation in terms of negative impacts on donor life expectancy. Given the close relationship between reduced kidney function in patients with chronic kidney disease (CKD) and hypertension, cardiovascular disease and cardiovascular mortality, information on the impact of kidney donation on these is particularly relevant. In this article, we review the existing evidence, focusing on the more recent studies on the impact of kidney donation on all-cause mortality, cardiovascular mortality, cardiovascular disease and hypertension, as well as markers of cardiovascular damage including arterial stiffness and uraemic cardiomyopathy. We also discuss the similarities and differences between the pathological reduction in renal function that occurs in CKD, and the reduction in renal function that occurs because of a donor nephrectomy. Kidney donors perform an altruistic act that benefits individual patients as well as the wider society. They deserve to have high-quality evidence on which to make informed decisions.

Left atrial strain: A novel "biomarker" for chronic kidney disease patients?

Cardiovascular disease and chronic kidney disease are frequently inter-connected and this association leads to an exponential growth of cardiovascular risk. This risk is currently underestimated by the existing algorithms and there is a constant need for new markers to predict adverse outcomes in this special population. In general population left atrial strain has emerged as an important tool for both the diagnosis and prognostic stratification, but data regarding its role in chronic kidney disease patients is scarce. The purpose of this review is to summarize the current evidence regarding this matter. Left atrial size and function mirror the duration and severity of increased left ventricular filling pressures. Increased left atrial volume index and impaired left atrial strain parameters are independent predictors for adverse cardiovascular events. Left atrial strain is impaired before changes in volume appear, thus being able to predict both diastolic and systolic function in chronic kidney disease patients. Finally, left atrial strain can identify renal patients with impaired exercise capacity and this could have clinical applications in the rehabilitation of this patients.

Effects of Spironolactone and Chlorthalidone on Cardiovascular Structure and Function in Chronic Kidney Disease: A Randomized, Open-Label Trial

BACKGROUND AND OBJECTIVES

In a randomized double-blind, placebo-controlled trial, treatment with spironolactone in early-stage CKD reduced left ventricular mass and arterial stiffness compared with placebo. It is not known if these effects were due to BP reduction or specific vascular and myocardial effects of spironolactone.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A prospective, randomized, open-label, blinded end point study conducted in four UK centers (Birmingham, Cambridge, Edinburgh, and London) comparing spironolactone 25 mg to chlorthalidone 25 mg once daily for 40 weeks in 154 participants with nondiabetic stage 2 and 3 CKD (eGFR 30-89 ml/min per 1.73 m²). The primary end point was change in left ventricular mass on cardiac magnetic resonance imaging. Participants were on treatment with an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker and had controlled BP (target ≤130/80 mm Hg).

RESULTS

There was no significant difference in left ventricular mass regression; at week 40, the adjusted mean difference for spironolactone compared with chlorthalidone was -3.8 g (95% confidence interval, -8.1 to 0.5 g, P=0.08). Office and 24-hour ambulatory BPs fell in response to both drugs with no significant differences between treatment. Pulse wave velocity was not significantly different between groups; at week 40, the adjusted mean difference for spironolactone compared with chlorthalidone was 0.04 m/s (-0.4 m/s, 0.5 m/s, P=0.90). Hyperkalemia (defined ≥5.4 mEq/L) occurred more frequently with spironolactone (12 versus two participants, adjusted relative risk was 5.5, 95% confidence interval, 1.4 to 22.1, P=0.02), but there were no patients with severe hyperkalemia (defined ≥6.5 mEq/L). A decline in eGFR >30% occurred in eight participants treated with chlorthalidone compared with two participants with spironolactone (adjusted relative risk was 0.2, 95% confidence interval, 0.05 to 1.1, P=0.07).

CONCLUSIONS

Spironolactone was not superior to chlorthalidone in reducing left ventricular mass, BP, or arterial stiffness in nondiabetic CKD.

Right Ventricular Functionality Following Hemodialysis Initiation in End-Stage Kidney Disease-A Single-Center, Prospective, Cohort Study

Background and Objectives: Two-dimensional speckle tracking echocardiography (2D-STE) is viewed as an outstanding technique, competent of uncovering earlier subclinical myocardial anomalies compared to conventional echocardiography. A few endeavors adopted 2D-STE as a tool to estimate right ventricular (RV) function in subjects with end-stage kidney disease (ESKD). There is no published prospective study on an adult ESKD cohort exploring the consequences of commencing elective hemodialysis (HD) on RV behavior. Materials and Methods: We investigated the RV systolic function using traditional (tricuspid annular plane systolic excursion-TAPSE, RV fractional area change-FAC) and 2D-STE (RV free wall longitudinal strain-RVFWLS) parameters following the initiation of HD. We enrolled 79 consecutive patients with ESKD and assessed them in four steps-at baseline, before HD, and at 3, 6, and 12 months. Results: RVFWLS, FAC, and TAPSE values had a significant increase at 3, 6, and 12 months from baseline (p < 0.001) and a significant increase at 6 months from 3 months (p < 0.001). However, differences between 12 months and 6 months were not significant (p > 0.05) according to Dunn-Bonferroni post hoc tests. Seventeen deaths were recorded before the completion of the study. RVFWLS, FAC, and TAPSE values significantly decreased at 3 and 6 months in all 17 deceased patients, in clear opposition with the values survivors had. All the studied parameters had a significant prediction power on mortality (p < 0.001) having an outstanding performance: baseline-RVFWLS (AUC: 1.000 (95% C.I.: 1.000-1.000)), baseline-FAC (AUC: 0.974 (95% C.I.: 0.942-1.000)), and baseline-TAPSE (AUC: 0.962 (95% C.I.: 0.920-1.000). Conclusions: Our study is the first to investigate RV function by 2D-STE and correlate it with traditional methods in patients with ESKD before and after the initiation of HD. RV function was significantly ameliorated at 3, 6, and 12 months compared to the pre-HD values. FAC and RVFWLS gain an outstanding prognostic role on mortality in this population.

Estimated left ventricular pressure-myocardial strain loop as an index of cardiac work predicts all-cause mortality in patients receiving regular hemodialysis

BACKGROUND

A non-invasive method for left ventricular pressure-strain analysis has recently been introduced to provide information on cardiac work and detect subtler changes in cardiac function. This study aims to verify and construct a novel index that could accurately and independently predict the prognosis of patients with end-stage kidney disease (ESRD) receiving regular hemodialysis.

METHODS

Patients with end-stage kidney disease (ESRD) receiving maintenance hemodialysis (4-h sessions, 3 times weekly for 3 months or more) and who underwent echocardiography between 2009 and 2014 in China Medical University Hospital, Taichung, Taiwan, were enrolled. Conventional (left ventricular ejection fraction, LVEF) and strain echocardiography parameters (global longitudinal strain, GLS; cardiac work index, CWI) in 102 eligible patients were analyzed and compared. CWI was calculated from estimated LV pressure-myocardial strain loop area.

RESULTS

Results show that, while no significant differences were found between LVEF (0.57 ± 0.12 vs. 0.59 ± 0.09, P = 0.27) and GLS (-16.12 ± 6.57% vs. -18.44 ± 5.54%, P = 0.07), deceased patients had significantly lower CWI (1339 ± 683.05 mmHg% vs. 1883.38 ± 640.99 mmHg%, P = 0.0002) than surviving patients. The predictive values defined by area under the curve (AUC) of LVEF, GLS and CWI were 0.499, 0.619 and 0.724, respectively.

CONCLUSION

In conclusion, CWI is an accurately independent predictor of all-cause mortality in ESRD patients receiving regular hemodialysis and may superior to the current predictors such as LVEF and GLS.

Evaluation of left ventricular systolic functions in two-dimensional speckle-tracking echocardiography in children with chronic renal failure

BACKGROUND AND AIM

Chronic kidney disease may lead to left ventricular dysfunction. Early detection of cardiovascular disease in children with chronic kidney disease is essential to prevent cardiovascular morbidity and mortality in early adulthood. This study aimed to document the dysfunction using methods such as two-dimensional speckle-tracking echocardiography in the early stage.

METHODS

A total of 34 patients diagnosed with chronic kidney disease (mean age ± standard deviation, 10.5 ± 4.1 years) and 37 sex- and age-matched (mean age 9.8 ± 4.2 years) healthy controls were studied. The results of the two groups were compared along with those of the published studies.

RESULTS

The echocardiography measurements had no significant difference in the end-diastolic and end-systolic diameter values of left ventricular, ejection fraction, shortening fraction, mitral E value, mitral A value, and E/A ratio between the groups. Pulmonary artery systolic and diastolic pressure and left ventricular mass index were significantly higher in the patient group (p < 0.01). The longitudinal global strain values in the apical four-chamber, three-chamber, and two-chamber views and the total global strain values were significantly lower in the patients (p < 0.01). The circumferential global strain values in the apical, mid, basal, and total global strain were lower in the patient group, but this difference was statistically significant in the apical global and total global strain values (p < 0.05).

CONCLUSIONS

Speckle-tracking echocardiography might help identify subclinical left ventricular dysfunction in patients with chronic kidney disease with unremarkable conventional echocardiography.

Cardiovascular Effects of Unilateral Nephrectomy in Living Kidney Donors at 5 Years

Supplemental Digital Content is available in the text.

Kidney donation reduces renal function by ≈30% allowing study of the cardiovascular effects of a reduced estimated glomerular filtration rate without comorbidities. We report 5-year results of a longitudinal, parallel-group, blinded end-point study of living kidney donors (n=50) and healthy controls (n=45). The primary end point, left ventricular mass, was measured using cardiac magnetic resonance. Secondary end points, 24-hour ambulatory blood pressure, and pulse wave velocity were measured using validated blood pressure monitors and the SphygmoCor device. Effect sizes were calculated as differences between change from baseline in the donor and control groups. In donors, estimated glomerular filtration rate was 95±15 mL/min per 1.73 m2 at baseline (predonation) and 67±14 mL/min per 1.73 m2 at 5 years. In controls, there was a −1±2 mL/min per 1.73 m2 decline per annum. Change in left ventricular mass at 5 years was not significantly different between donors and controls (mean difference, +0.40 g [95% CI, −4.68 to 5.49] P=0.876), despite an initial increase in mass in donors compared with controls at 12 months. Pulse wave velocity, which increased in donors at 12 months, returned to levels not different from controls at 5 years (mean difference, −0.24 m/s [95% CI, −0.69 to 0.21]). Change in ambulatory systolic blood pressure was not different in donors compared with controls (mean difference, +1.91 mm Hg [95% CI, −2.72 to 6.54]). We found no evidence that the reduction in estimated glomerular filtration rate after kidney donation was associated with a change in left ventricular mass detectable by magnetic resonance imaging at 5 years.

Speckle-tracking echocardiography in comparison with ejection fraction for prediction of cardiovascular mortality in patients with end-stage renal disease

Background

Cardiovascular disease is the major cause of death in end-stage renal disease (ESRD). To develop better means to assess cardiovascular risk in these patients, we compared conventional echocardiography-derived left ventricular ejection fraction (EF) with the novel method of 2D speckle-tracking echocardiography to determine cardiac strain.

Methods

Predictive performances of conventional EF and speckle-tracking echocardiography-derived global longitudinal strain (GLS) were compared using receiver-operator curve (ROC) analyses and calibration by calibration plots. We also took into account other known cardiovascular risk factors through multivariable logistic regression analysis.

Results

The study comprised 171 ESRD patients (mean age 64 years, 64% male) on maintenance dialysis therapy (93% haemodialysis, 7% peritoneal dialysis) for an average period of 39 months. During 2.1 years of follow-up, 42 patients (25%) died from cardiovascular disease. ROC analysis of GLS resulted in an area under the curve of 0.700 [95% confidence interval (CI) 0.603–0.797] compared with an area under the curve of EF of 0.615 (95% CI 0.514–0.716) (P = 0.059 for difference). The total absolute deviation between predicted and observed outcome frequencies obtained by calibration plots were 13.8% for EF compared with only 6.4% for GLS. Best results of ROC analysis (area under the curve = 0.759; P = 0.06), calibration and goodness-of-fit (χ² = 28.34, P ≤ 0.0001, R² = 0.25) were achieved for GLS added to a baseline model consisting of known cardiovascular risk factors in a multivariate regression analysis.

Conclusions

In summary, in chronic dialysis patients, GLS is a more precise predictor of cardiovascular mortality than conventional echocardiography-derived EF.

Left Atrial Strain Is the Best Predictor of Adverse Cardiovascular Outcomes in Patients with Chronic Kidney Disease

BACKGROUND

Patients with chronic kidney disease (CKD) are at increased risk of adverse cardiovascular events, which is underestimated by traditional risk stratification algorithms. We sought to determine clinical and echocardiographic predictors of adverse outcomes in CKD patients.

METHODS

Two hundred forty-three prospectively recruited stage 3/4 CKD patients (male, 63%; mean age, 59.2 ± 14.4 years) without previous cardiac disease made up the study cohort. All participants underwent a transthoracic echocardiogram, with left ventricular (LV) and left atrial (LA) strain analysis. Participants were followed for 3.9 ± 2.7 years for the primary end point of cardiovascular death and major adverse cardiovascular event (MACE). The secondary end point was the composite of all-cause death and MACE.

RESULTS

Fifty-four patients met the primary end point, and 65 the secondary end point. On log-rank tests, older age, diabetes mellitus, anemia, greater LV mass, reduced LV global longitudinal strain, larger indexed LA volume, higher E/e' ratio, and reduced LA reservoir strain (LASr; P < .01 for all) were independent predictors of cardiovascular death and MACE. On multivariable regression analysis of univariate predictors, LASr (P < .01) was the only independent predictor for the primary end point as well as for the secondary end point. Receiver operating characteristic curve analysis showed LASr was a stronger predictor of adverse events (area under the curve [AUC] = 0.84) compared to the Framingham (AUC = 0.58) and Atherosclerotic Cardiovascular Disease (AUC = 0.59) risk scores.

CONCLUSIONS

LASr is an independent predictor of cardiovascular death and MACE in CKD patients, superior to clinical risk scores, LV parameters, and LA volume.

Chronic kidney disease, heart failure and neprilysin inhibition

Patients with chronic kidney disease are at increased risk of cardiovascular disease and this often manifests clinically like heart failure. Conversely, patients with heart failure frequently have reduced kidney function. The links between the kidneys and cardiovascular system are being elucidated, with blood pressure being a key risk factor. Patients with heart failure have benefitted from many trials which have now established a strong evidence based on which to base management. However, patients with advanced kidney disease have often been excluded from these trials. Nevertheless, there is little evidence that the benefits of such treatments are modified by the presence or absence of kidney disease, but more direct evidence among patients with advanced kidney disease is required. Neprilysin inhibition is the most recent treatment to be shown to improve outcomes among patients with heart failure. The UK HARP-III trial assessed whether neprilysin inhibition improved kidney function in the short- to medium-term and its effects on cardiovascular biomarkers. Although no effect (compared to irbesartan control) was found on kidney function, allocation to neprilysin inhibition (sacubitril/valsartan) did reduce cardiac biomarkers more than irbesartan, suggesting that this treatment might improve cardiovascular outcomes in this population. Larger clinical outcomes trials are needed to test this hypothesis.

Assessment of left ventricular deformation in patients with type 2 diabetes mellitus by cardiac magnetic resonance tissue tracking

To quantify the global and regional left ventricular (LV) myocardial strain in type 2 diabetes mellitus (T2DM) patients using cardiac magnetic resonance (CMR) tissue-tracking techniques and to determine the ability of myocardial strain parameters to assessment the LV deformation. Our study included 98 adult T2DM patients (preserved LV ejection fraction [LVEF], 72; reduced LVEF, 26) and 35 healthy controls. Conventional LV function, volume-time curve parameters and LV remodeling index were measured using CMR. Global and regional LV myocardial strain parameters were measured using CMR tissue tracking and compared between the different sub-groups. Receiver operating characteristic analysis was used to assess the diagnostic accuracy. Regression analyses were conducted to determine the relationship between strain parameters and the LV remodeling index. The results show that global radial peak strain (PS) and circumferential PS were not significantly different between the preserved-LVEF group and control group (P > 0.05). However, longitudinal PS was significantly lower in the preserved-LVEF group than in the control group (P = 0.005). Multivariate linear and logistic regression analyses showed that global longitudinal PS was independently associated (β = 0.385, P < 0.001) with the LV remodeling index. In conclusion, early quantitative evaluation of cardiac deformation can be successfully performed using CMR tissue tracking in T2DM patients. In addition, global longitudinal PS can complement LVEF in the assessment of cardiac function.

Assessment of left ventricular energy loss using vector flow mapping in patients with stages 1-3 chronic kidney disease

BACKGROUND

Patients with chronic kidney disease (CKD) experience abnormality of intracardiac blood flow status during early-stages of disease. Left ventricular energy loss (EL) derived from vector flow mapping (VFM) represents fluid energy lost as heat in left ventricle and had been used to detect intracardiac blood flow efficiency. We aimed to evaluate the left ventricular EL in stage 1-3 CKD patients, and explored whether hypertension, a main cardiovascular risk, deteriorate the abnormality of intracardiac blood flow status.

METHODS

Transthoracic echocardiography was performed in 41 controls and 48 patients with stages 1-3 CKD. CKD patients consisted a subgroup with no hypertension, a subgroup with well-controlled hypertension and a subgroup with poorly controlled hypertension. The EL were calculated in the left ventricle using VFM analysis from the apical 3-chamber view. Furthermore, the correlation and stepwise multiple regression analysis were used to explore the potential independent predictors of left ventricular EL.

RESULTS

Compared with controls, stage 1-3 CKD patients showed increased left ventricular EL during total diastole, late diastole, total systole, isovolumic contraction and ejection. CKD patients with poorly controlled hypertension had higher left ventricular EL compared to the other CKD subgroups. Additionally, the ratio of mitral early filling wave peak velocity and early mitral annular peak velocity on septal side, mitral early filling wave peak velocity, and left ventricular mass index were independent predictors of the diastolic EL; whereas systolic blood pressure and left ventricular mass index were independent predictors of the systolic EL.

CONCLUSIONS

Left ventricular EL was a useful echocardiographic parameter to evaluate the impaired intracardiac blood flow efficiency in patients with stages 1-3 CKD. Hypertension was a crucial contributor for intracardiac blood flow abnormality. This study might provide valuable clinical data to discern cardiac dysfunction and reduce the cardiovascular risk in early-stage CKD.

Left Ventricular Myocardial Deformations in Hemodialysis Children by Speckle Tracking Echocardiography

Background:

Cardiac systolic dysfunction was potentially found in adult patients with end-stage renal disease (ESRD) who have preserved left ventricular ejection fraction (EF%). In children with ESRD, little data are available on early changes in myocardial function. This study aimed to detect the early changes in myocardial mechanics in pediatric patients with ESRD using speckle tracking echocardiography (STE).

Methods:

Thirty ESRD children receiving hemodialysis (HD) and30 age-matched controls were prospectively studied. Patients underwent echocardiographic studies before and after HD. Left ventricular longitudinal strain (LS), circumferential strain (CS), and radial strain (RS) myocardial deformation parameters (strain, strain rate) were evaluated by STE.

Results:

The LS was significantly reduced in pre-HD and post-HD patients compared with controls (P = .000). Controls showed the highest global longitudinal strain. The RS measurements did not differ significantly among the studied groups except for the inferior segment that is significantly reduced after HD compared with controls (P < .05). The CS was significantly reduced in pre-HD and post-HD patients compared with controls at the lateral and posterior segments (P = .035 and P = .013, respectively).

Conclusion:

Speckle-tracking echocardiography might detect early changes in myocardial mechanics in children with ESRD with preserved EF%.

Prognostic value of left ventricular global longitudinal strain in chronic kidney disease patients: a systematic review and meta-analysis

OBJECTIVE

The objective of this meta-analysis was to evaluate whether left ventricular global longitudinal strain (GLS) is a potential marker of predicting adverse outcomes in CKD patients.

BACKGROUND

CKD is a growing health burden currently affecting 10-15% of adults worldwide, and disproportionally increasing propensity to develop cardiovascular diseases and events. Although obtained from several relatively small studies, the evidence supporting the prognostic value of GLS in patients with CKD is still building.

METHODS

We conducted a Medline literature research using electronic databases (PubMed, Ovid, Embase and Web of Science) to identify relevant studies reporting the association between GLS and the primary outcomes, including all-cause mortality, major cardiac events (MCE), and cardiovascular mortality in CKD patients. Sensitivity analysis and subgroup analysis were performed to find the origin of heterogeneity.

RESULTS

A total of 11 observational studies with 2167 patients with CKD were enrolled. In patients with CKD, GLS was associated with all-cause mortality (HR: 1.09, 95% CI 1.06-1.12) with no heterogeneity among the studies (I² = 46.5%, P = 0.06). In addition, GLS was associated with MCE and cardiovascular mortality with no heterogeneity (HR 1.16, 95% CI 1.11-1.22; HR 1.18, 95% CI 1.12-1.24, respectively). Overall, GLS was also associated with combined adverse events in CKD patients (HR 1.09, 95% CI 1.07-1.12) with moderate heterogeneity (I² = 51.2%, P = 0.025).

CONCLUSIONS

Our meta-analysis demonstrates that GLS is associated with all-cause mortality, MCE, cardiovascular mortality, and combined adverse events in CKD patients.

Relationship between Microfibrillar-Associated Protein 4 Levels and Subclinical Myocardial Damage in Chronic Kidney Disease

INTRODUCTION

Chronic kidney disease (CKD) is a widespread health problem, in which mortality is most frequently due to cardiovascular diseases. Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein. MFAP4 is involved in several biological processes, particularly the maintenance of vascular integrity and extracellular matrix remodeling. Our review of the literature revealed no data concerning MFAP4 levels in CKD and its relationship with myocardial functions.

OBJECTIVE

The purpose of this study was therefore to investigate MFAP4 levels in CKD, parameters affecting these, and the relationship with myocardial functions.

MATERIALS AND METHODS

Seventy-nine CKD patients and 30 healthy controls were included in the study. Routine biochemical tests and echocardiography were performed once demographic data had been recorded. Blood specimens were collected for MFAP4 analysis, and the results were subjected to statistical analysis.

RESULTS

MFAP4 levels were significantly higher in the patient group than in the control group (p< 0.001). Doppler parameters revealed more frequent LV diastolic impairment in the patient group. Tissue Doppler systolic velocity and global longitudinal strain were significantly impaired, revealing the subclinical LV systolic dysfunction in CKD patients. MFAP4 elevation in the patient group was positively correlated with aortic root (AR), global circumferential strain (GCS), and GCS rate.

CONCLUSION

Our results showed MFAP4 elevation in CKD for the first time in the literature, and that this elevation may be related to GCS and AR dilation. We think that, once supported by further studies, MFAP4 may constitute a marker in the evaluation of myocardial functions in CKD.

Clinical Potential of Targeting Fibroblast Growth Factor-23 and αKlotho in the Treatment of Uremic Cardiomyopathy

Chronic kidney disease is highly prevalent, affecting 10% to 15% of the adult population worldwide and is associated with increased cardiovascular morbidity and mortality. As chronic kidney disease worsens, a unique cardiovascular phenotype develops characterized by heart muscle disease, increased arterial stiffness, atherosclerosis, and hypertension. Cardiovascular risk is multifaceted, but most cardiovascular deaths in patients with advanced chronic kidney disease are caused by heart failure and sudden cardiac death. While the exact drivers of these deaths are unknown, they are believed to be caused by uremic cardiomyopathy: a specific pattern of myocardial hypertrophy, fibrosis, with both diastolic and systolic dysfunction. Although the pathogenesis of uremic cardiomyopathy is likely to be multifactorial, accumulating evidence suggests increased production of fibroblast growth factor-23 and αKlotho deficiency as potential major drivers of cardiac remodeling in patients with uremic cardiomyopathy. In this article we review the increasing understanding of the physiology and clinical aspects of uremic cardiomyopathy and the rapidly increasing knowledge of the biology of both fibroblast growth factor-23 and αKlotho. Finally, we discuss how dissection of these pathological processes is aiding the development of therapeutic options, including small molecules and antibodies, directly aimed at improving the cardiovascular outcomes of patients with chronic kidney disease and end-stage renal disease.

Speckle Tracking Echocardiography and All-Cause and Cardiovascular Mortality Risk in Chronic Kidney Disease Patients

Background and Objectives: Patients with chronic kidney disease (CKD) exhibit a highly increased risk of cardiovascular (CV) morbidity and mortality. Subtle changes in left ventricular function can be detected by two-dimensional (2D) speckle tracking echocardiography (STE). This study investigated whether myocardial dysfunction detected by 2D STE may aid in CV and all-cause mortality risk assessment in patients with CKD stages 3 and 4. Method: A study group of 285 patients (CKD 3: 193 patients; CKD 4: 92 patients) and a healthy control group (34 participants) were included in the retrospective study. 2D STE values as well as early and late diastolic strain rates were measured in ventricular longitudinal, circumferential and radial directions. Patients’ CV and all-cause outcome was determined. Results: In the CKD group all measured longitudinal STE values and radial strain were significantly reduced compared to the control group. Cox proportional hazards regression revealed global longitudinal strain to predict CV and all-cause mortality (hazard ratio [HR] 1.15, 95% CI 1.06–1.25; p = 0.0008 and HR 1.09, 95% CI 1.04–1.14; p = 0.0003). After adjustment for sex, age, diabetes, estimated glomerular filtration rate, and preexisting CV disease, this association was maintained for CV mortality and all-cause mortality (HR 1.16, 95% CI 1.06–1.27; p = 0.0019 and HR 1.08, 95% CI 1.03–1.14; p = 0.0026, respectively). Conclusions: The present study shows that 2D STE detects reduced left ventricular myocardial function and allows the prediction of CV and all-cause mortality in patients at CKD stages 3 and 4.

Cardiovascular magnetic resonance left ventricular strain in end-stage renal disease patients after kidney transplantation

BACKGROUND

Cardiovascular disease is a significant cause of morbidity and mortality in patients with end-stage renal disease (ESRD) and kidney transplant (KT) patients. Compared with left ventricular (LV) ejection fraction (LVEF), LV strain has emerged as an important marker of LV function as it is less load dependent. We sought to evaluate changes in LV strain using cardiovascular magnetic resonance imaging (CMR) in ESRD patients who received KT, to determine whether KT may improve LV function.

METHODS

We conducted a prospective multi-centre longitudinal study of 79 ESRD patients (40 on dialysis, 39 underwent KT). CMR was performed at baseline and at 12 months after KT.

RESULTS

Among 79 participants (mean age 55 years; 30% women), KT patients had significant improvement in global circumferential strain (GCS) (p = 0.007) and global radial strain (GRS) (p = 0.003), but a decline in global longitudinal strain (GLS) over 12 months (p = 0.026), while no significant change in any LV strain was observed in the ongoing dialysis group. For KT patients, the improvement in LV strain paralleled improvement in LVEF (57.4 ± 6.4% at baseline, 60.6% ± 6.9% at 12 months; p = 0.001). For entire cohort, over 12 months, change in LVEF was significantly correlated with change in GCS (Spearman's r = - 0.42, p < 0.001), GRS (Spearman's r = 0.64, p < 0.001), and GLS (Spearman's r = - 0.34, p = 0.002). Improvements in GCS and GRS over 12 months were significantly correlated with reductions in LV end-diastolic volume index and LV end-systolic volume index (all p < 0.05), but not with change in blood pressure (all p > 0.10).

CONCLUSIONS

Compared with continuation of dialysis, KT was associated with significant improvements in LV strain metrics of GCS and GRS after 12 months, which did not correlate with blood pressure change. This supports the notion that KT has favorable effects on LV function beyond volume and blood pessure control. Larger studies with longer follow-up are needed to confirm these findings.

2D-Speckle tracking echocardiography contributes to early identification of impaired left ventricular myocardial function in children with chronic kidney disease

IntroductionThe aim of this study is to determine early changes in cardiac function of children with chronic kidney disease by using 2D-speckle tracking echocardiography.

METHOD

The study included 38 children - 16 girls and 22 boys - diagnosed as having chronic kidney disease in the nephrology department with a glomerular filtration rate of <90 ml/minute/1.73 m2 for at least 3 months. A total of 37 - 15 girls and 22 boys - age- and sex-matched healthy children were included as the control group. 2D-Speckle tracking echocardiography was performed in all subjects.

RESULTS

The mean age was 13.45±2.8 years in patients and 12.89±3.07 years in controls. Systolic and diastolic blood pressures and left ventricular mass index were significantly higher in patients (p<0.05). The values of mitral e, mitral a, mitral e/a ratio, and mitral deceleration time were not different between the groups. Tricuspid annular plane systolic excursion values were lower in patients (p<0.01). Global strain values in apical long-axis 3-chamber and 2-chamber views were significantly lower in patients (p<0.05). Longitudinal, radial, and circumferential peak systolic strain values were lower in patients, but the difference was statistically significant in all segments of longitudinal view and basal segment of circumferential view (p<0.05). Radial and circumferential systolic strain rates were significantly lower in patients in all three segments (p<0.05). Moreover, early diastolic strain rate was significantly lower in longitudinal and radial apical segments and in all segments of circumferential measurements in patients. Besides, strain rate e/a ratio was significantly lower in all longitudinal segments of patients (p=0.01).

CONCLUSION

The study concluded that 2D-speckle tracking echocardiography method can determine cardiac involvement earlier than conventional echocardiography in children with chronic kidney disease having preserved ejection fraction.

Impaired Left Ventricular Global Longitudinal Strain among Patients with Chronic Kidney Disease and End-Stage Renal Disease and Renal Transplant Recipients

BACKGROUND

Although heart failure is the most prevalent cardiovascular disease associated with adverse outcome in chronic kidney disease (CKD) and after kidney transplantation, left ventricular (LV) systolic function is often preserved in renal patients. The aim of this study was to evaluate global longitudinal strain (GLS), which is reportedly a more accurate tool for detecting subclinical LV systolic dysfunction, in patients with various degrees of renal function impairment, including kidney transplant recipients (KTRs).

METHODS

This prospective study evaluated demographic, clinical, and ultrasound data, including the assessment of LV GLS and mitral E peak velocity and averaged ratio of mitral to myocardial early velocities (E/e'), of 70 consecutive renal patients (20 with stage 2-4 CKD, 25 with end-stage renal disease on hemodialysis [HD], and 25 KTRs). All patients had an LV ejection fraction ≥50% and no history of heart failure or coronary artery disease. We used multivariable logistic analysis to assess the risk of compromised GLS. One hundred and twenty control subjects with or without hypertension served as controls.

RESULTS

A compromised GLS <-18% was shown in 55% of patients with stage 2-4 CKD, 60% of HD patients, and 28% of KTRs, while it was 32% in hypertensive controls and 12% in non-hypertensive controls (p < 0.0001). Patients with HD had higher systolic pressure and a significantly greater prevalence of increased LV mass and diastolic dysfunction. In renal patients, E/e' (p = 0.025), and LV mass index (p = 0.063) were independent predictors of compromised GLS at logistic regression analysis. E/e', systolic artery pressure, and LV mass also exhibited the greatest areas under the curve on receiver operating characteristic analysis to identify a compromised GLS.

CONCLUSIONS

Renal disease proved to be associated with early and subclinical impairment of LV systolic function, which persists after starting dialysis and even in spite of successful kidney transplantation. An increased E/e' resulted to be the most powerful independent predictor of abnormal GLS.

Changes of Left and Right Ventricle Mechanics and Function in Patients with End-Stage Renal Disease Undergoing Haemodialysis

Background and objectives: Chronic kidney disease (CKD) increases the risk of cardiovascular diseases even in its early stages and is associated with structural and functional cardiac abnormalities. The aim of this study was to use speckle-tracking echocardiography (STE) to evaluate left and right ventricle mechanics and function, markers of subclinical dysfunction in patients with end-stage renal disease (ESRD) undergoing haemodialysis. Methods: Patients with ESRD undergoing regular haemodialysis and with preserved left ventricle (LV) ejection fraction (EF) (n = 38) were enrolled in this retrospective study. The control group consisted of 32 age-matched persons with normal kidney function (glomerular filtration rate (GFR) >90 mL/min/1.73 m² according to Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI)). Conventional 2D echocardiography and STE were performed in all patients. Results: 70 individuals, 31 (44.29%) males and 39 (55.71%) females, were included in the study. There were no significant differences in age, sex and body surface area between the groups. LV end diastolic diameter did not differ between the groups, while LV myocardial mass index was higher in the group of patients on haemodialysis (111.64 ± 27.99 versus 84.21 ± 16.99, p < 0.001) and LV diastolic dysfunction (LVDD) was found in 31 (81.6%) patients of this group. LV global longitudinal strain (GLS) (-22.43 ± 2.71 versus -24.73 ± 2.03, p < 0.001) and LV global circumferential strain (GCS) at the mitral valve and papillary muscles levels (-18.73 ± 3.49 versus -21.67 ± 2.22, p < 0.001; -18.64 ± 2.75 versus -20.42 ± 2.38, p = 0.005, respectively) were significantly lower in haemodialysis group patients. The parameters of the right ventricle (RV) free wall longitudinal function including RV GLS (-22.63 ± 3.04 versus -25.45 ± 2.48, p < 0.001), were reduced in haemodialysis patients compared with the controls. However, RV fractional area change (FAC) did not differ between the groups (p = 0.19). Conclusion: Patients with ESRD and preserved LV ejection fraction undergoing haemodialysis had a higher prevalence of LVDD and impaired LV longitudinal and circumferential deformation indices, as well as reduced RV longitudinal function and deformation parameters compared with the age-matched healthy controls. STE helps to detect subclinical LV and RV dysfunction in chronic haemodialysis patients.

Clinical utility of left ventricular strain, wall stress and serum brain natriuretic peptide levels in chronic hemodialysis patients

Background

Left ventricular (LV) global longitudinal strain (GLS) reliably assesses LV systolic function. The precise relation between LV wall stress and serum Brain natriuretic peptide (BNP) concentrations in hemodialysis (HD) patients needs to be clarified. BNP levels are raised in patients with end-stage renal disease (ESRD) and could reflect LV impairment among HD patients.

Aim of this work

This study sought to evaluate the clinical utility of LV-GLS, wall stress and serum BNP levels in chronic HD patients. The correlations between BNP levels with both LV wall stress and LV-GLS were assessed.

Patients and methods

30 ESRD patients on regular HD {categorized into 15 patients with LV ejection fraction (EF) ≤ 50% and 15 patients with LV EF > 50%} and 15-age matched healthy subjects were included. LV function and structure were assessed by conventional echocardiography including LV meridional wall stress (LVMWS), LV mass index (LVMI) and 2-dimensional speckle tracking echocardiography for determination of LV-GLS. Serum BNP levels were evaluated after HD session.

Results

There were significant increase of LVMSW (189.2 ± 81 vs. 72.2 ± 20.6 dynes/cm² × 1000, P < 0.0001), higher levels of BNP (1238 ± 1085.5 vs. 71 ± 23.4 pg/ml, P < 0.0001) while LV-GLS was significantly reduced (15.1 ± 3.1 vs. 20.8 ± 1.7%, P < 0.0001) in HD patients compared to controls. Higher values of LVMWS (246.9 ± 67.5 vs. 131.5 ± 43.6 dynes/cm² × 1000, P < 0.0001) and BNP (1925.4 ± 1087 vs. 550.5 ± 496.5 pg/ml, P < 0.0005) with further impairment of LV-GLS (13.8 ± 2.5 vs. 16.4 ± 5.4%, P < 0.05) were found in patients with LV EF ≤ 50% than those with LV EF > 50%. Serum levels of BNP were positively correlated with LVMI (r = 0.896, P < 0.0001) and LVMWS (r = 0.697, P < 0.0001) but negatively correlated with LV-GLS (r = −0.587, P < 0.0001).

Conclusion

LV-GLS and LVMWS are useful imaging markers for detection of LV dysfunction in HD patients. Serum BNP level is influenced by LV structural abnormalities and suggested to be a crucial hemodynamic biomarker in those patients.

The effect of different treatment strategies on left ventricular myocardial deformation parameters in patients with chronic renal failure

The aim of this study was to compare left ventricular (LV) functions by speckle tracking echocardiography (STE) in chronic kidney disease (CKD) patients in various stages and under different renal replacement treatments in order to evaluate possible differences between them. This prospective study included 150 patients with CKD. Renal transplantation patients with glomerular filtration rate greater than 60 ml/min/1.73 m², patients receiving hemodialysis three times a week, and patients in the predialysis stage with glomerular filtration rate less than 30 ml/dk/1.73 m² were assigned into Group 1 (n = 50), Group 2 (n = 50), and Group 3 (n = 50), respectively. LV longitudinal, circumferential, and radial myocardial deformation parameters (strain, strain rate [SR], rotation, twist) were evaluated by STE. Peak systolic longitudinal strain was higher in the transplantation group than the hemodialysis group (- 19.93 ± 3.50 vs - 17.47 ± 3.28%, p < 0.017). Peak systolic circumferential strain was lower in the hemodialysis group (- 20.97 ± 4.90%) than Groups 1 and 3 (- 25.87 ± 4.20 and - 24.74 ± 4.55%, respectively, p < 0.001). Peak systolic radial SR was higher in the transplantation group than the hemodialysis group (1.84 ± 0.52 vs 1.55 ± 0.52 s^-1, respectively, p < 0.017). Other longitudinal and circumferential deformation parameters together with peak early diastolic radial SR and twist were also significantly different between the groups. Strain, SR, and twist values were mostly lower in the hemodialysis patients, but generally higher in the transplantation patients. LV functions evaluated by STE are better in the renal transplantation patients than the hemodialysis patients and than those in the predialysis stage. This may indicate beneficial effects of renal transplantation on cardiac functions.

The association between soluble klotho and cardiovascular parameters in chronic kidney disease: results from the KNOW-CKD study

BACKGROUND

Klotho, a protein linked to aging, has emerged as a pivotal player in mineral bone metabolism and might explain the relationship between chronic kidney disease (CKD) and cardiovascular disease (CVD). The present study aimed to investigate the association between serum klotho and cardiac parameters from a large-scale Korean CKD cohort.

METHODS

We analyzed 2101 participants from KoreaN Cohort Study for Outcome in Patients With Chronic Kidney Disease (KNOW-CKD) cohort who had been measured for serum klotho levels. Left ventricular hypertrophy evaluated by left ventricular mass index (LVMI) and arterial stiffness measured by brachial-to-ankle pulse wave velocity (baPWV) were explored as cardiovascular parameters.

RESULTS

Patients were 53.6 ± 12.2 years old and 61.1% were male. The mean estimated glomerular filtration rate (eGFR) was 53.0 ± 30.7 mL/min/1.73m². The median serum klotho level was 536 (interquartile range [IQR]: 420-667) pg/mL. Advanced CKD stages were associated with lower serum klotho levels (P < 0.001, P for linear trend < 0.001). Ascending quartiles of klotho were significantly associated with decreased LMVI (P < 0.001, P for linear trend< 0.001). A multivariable linear regression model showed serum klotho had a significant inverse association with LVMI (β - 0.04; 95% CI [confidence interval] -0.004, - 0.00007; P = 0.041). However, there was no significant association between serum klotho and baPWV after adjustment (β 0.003; 95% CI -0.04, 0.05; P = 0.876).

TRIAL REGISTRATION

This trial was registered on ClinicalTrials.gov on 28 June 2012 ( NCT01630486 ).

CONCLUSIONS

Serum klotho was an independent biomarker of LVMI, but not arterial stiffness.

Longitudinal assessment of myocardial function in childhood chronic kidney disease, during dialysis, and following kidney transplantation

BACKGROUND

Childhood chronic kidney disease (CKD) and dialysis are associated with increased long-term cardiovascular risk. We examined subclinical alterations in myocardial mechanics longitudinally in children with CKD, during dialysis, and following renal transplantation.

METHODS

Forty-eight children with CKD (stage III or higher) who received kidney transplants from 2008 to 2014 were included in a retrospective study and compared to 192 age- and sex-matched healthy children. Measurements of cardiac systolic and diastolic function were performed, and global longitudinal strain (GLS) and circumferential strain (GCS) were measured by speckle-tracking echocardiography at CKD, during dialysis, and 1 year following kidney transplantation. Mixed-effects modeling examined changes in GLS and GCS over different disease stages.

RESULTS

Children with CKD had a mean age of 10 ± 5 years and 67% were male. Eighteen children received preemptive transplantation. Children with CKD had increased left ventricular mass, lower GLS, and impaired diastolic function (lower E/A ratio and E' velocities) than healthy children. Changes in left ventricular diastolic parameters persisted during dialysis and after renal transplantation. Dialysis was associated with reduced GLS compared to CKD (β = 1.6, 95% confidence interval 0.2-3.0); however, this was not significant after adjustment for systolic blood pressure and CKD duration. Post-transplantation GLS levels were similar to those at CKD assessment. GCS was unchanged during dialysis but significantly improved following transplantation.

CONCLUSIONS

There are differences in diastolic parameters in childhood CKD that persist during dialysis and after transplantation. Systolic parameters are preserved, with significant improvement in systolic myocardial deformation following transplantation. The impact of persistent diastolic changes on long-term outcomes requires further investigation.

Echocardiographic assessment in patients with chronic kidney disease: Current update

Patients with chronic kidney disease (CKD) carry a high cardiovascular risk. An abundance of evidence has emerged in recent years establishing minor reductions in estimated glomerular filtration rate as an independent risk factor for cardiovascular mortality. Additionally, cardiac changes, such as left ventricular hypertrophy and impaired left ventricular systolic function, have been associated with an unfavorable prognosis. Despite the significant prevalence of underlying cardiac abnormalities, symptoms may not manifest in many patients with CKD. A range of available and emerging echocardiographic modalities may assist with diagnosing heart disease in CKD. Furthermore, some of these emerging techniques can give an important insight into the pathophysiology of subclinical dysfunction in CKD. This review discusses how current and emerging echocardiographic modalities such as speckle tracking echocardiography and 3D echocardiography might help cardiologists in providing important information to help with diagnosis and risk stratification of cardiac-related morbidity and mortality in patients with renal disease, as well applicability of these tools to current clinical practice.

Myocardial dysfunction occurs prior to changes in ventricular geometry in mice with chronic kidney disease (CKD)

Uremic cardiomyopathy is responsible for high morbidity and mortality rates among patients with chronic kidney disease (CKD), but the underlying mechanisms contributing to this complex phenotype are incompletely understood. Myocardial deformation analyses (ventricular strain) of patients with mild CKD have recently been reported to predict adverse clinical outcome. We aimed to determine if early myocardial dysfunction in a mouse model of CKD could be detected using ventricular strain analyses. CKD was induced in 5-week-old male 129X1/SvJ mice through partial nephrectomy (5/6Nx) with age-matched mice undergoing bilateral sham surgeries serving as controls. Serial transthoracic echocardiography was performed over 16 weeks following induction of CKD. Invasive hemodynamic measurements were performed at 8 weeks. Gene expression and histology was performed on hearts at 8 and 16 weeks. CKD mice developed decreased longitudinal strain (-25 ± 4.2% vs. -29 ± 2.3%; P = 0.01) and diastolic dysfunction (E/A ratio 1.2 ± 0.15 vs. 1.9 ± 0.18; P < 0.001) compared to controls as early as 2 weeks following 5/6Nx. In contrast, ventricular hypertrophy was not apparent until 4 weeks. Hearts from CKD mice developed progressive fibrosis at 8 and 16 weeks with gene signatures suggestive of evolving heart failure with elevated expression of natriuretic peptides. Uremic cardiomyopathy in this model is characterized by early myocardial dysfunction which preceded observable changes in ventricular geometry. The model ultimately resulted in myocardial fibrosis and increased expression of natriuretic peptides suggestive of progressive heart failure.

Association of chronic kidney disease with abnormal cardiac mechanics and adverse outcomes in patients with heart failure and preserved ejection fraction

AIMS

Chronic kidney disease (CKD) is associated with worse outcomes in heart failure with preserved ejection fraction (HFpEF). Whether this association is due the effect of CKD on intrinsic abnormalities in cardiac function is unknown. We hypothesized that CKD is independently associated with worse cardiac mechanics in HFpEF.

METHODS AND RESULTS

We prospectively studied 299 patients enrolled in the Northwestern University HFpEF Program. Using the creatinine-based CKD-Epi equation to calculate estimated glomerular filtration rate (eGFR), study participants were analysed by CKD status (using eGFR <60 mL/min/1.73 m(2) to denote CKD). Indices of cardiac mechanics (longitudinal strain parameters) were measured using speckle-tracking echocardiography. Using multivariable-adjusted linear and Cox regression analyses, we determined the association between CKD and echocardiographic parameters and clinical outcomes (cardiovascular hospitalization or death). Of 299 study participants, 48% had CKD. CKD (dichotomous variable) and reduced eGFR (continuous variable) were both associated with worse cardiac mechanics indices including left atrial (LA) reservoir strain, LV longitudinal strain, and right ventricular free wall strain even after adjusting for potential confounders, including co-morbidities, EF, and volume status. For example, for each 1-SD decrease in eGFR, LA reservoir strain was 3.52% units lower (P < 0.0001) after multivariable adjustment. Reduced eGFR was also associated with worse outcomes [adjusted hazard ratio (HR) 1.28, 95% confidence interval (CI) 1.01-1.61 per 1-SD decrease in eGFR; P = 0.039]. The association was attenuated after adjustment for indices of cardiac mechanics (P = 0.064).

CONCLUSION

In HFpEF, CKD is independently associated with worse cardiac mechanics, which may explain why HFpEF patients with CKD have worse outcomes.

TRIAL REGISTRATION

NCT01030991.

Advanced Parameters of Cardiac Mechanics in Children with CKD: The 4C Study

BACKGROUND AND OBJECTIVES

Newer parameters of cardiac mechanics provide additional insights on cardiac dysfunction in adult patients with CKD. The aim of this study was to identify prevalence of subclinical abnormalities in cardiac function through the analysis of novel indices of cardiac mechanics in a large population of children with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Between 2009 and 2011, the prospective observational Cardiovascular Comorbidity in Children with CKD Study enrolled patients with CKD ages 6-17 years old with eGFR=10-45 ml/min per 1.73 m(2) in 14 European countries. Cardiac morphology and function were assessed through echocardiography. The analysis presented encompasses global radial, longitudinal, and circumferential strains as well as time to peak analysis. Data were compared with 61 healthy children with comparable age and sex.

RESULTS

Data on 272 patients with CKD with complete echocardiographic assessment are reported (age =12.8±3.5 years old; 65% boys). Patients with CKD showed mildly higher office BP values and higher prevalence of left ventricular hypertrophy, but no differences were observed among groups in left ventricular ejection fraction. Strain analysis showed significantly lower global radial strain (29.6%±13.3% versus 35.5%±8.9%) and circumferential strain components (-21.8%±4.8% versus -28.2%±5.0%; both P<0.05) in patients with CKD without significant differences observed in longitudinal strain (-15.9%±3.4% versus -16.2%±3.7%). Lower values of global radial strain were associated with lower circumferential endocardial-to-epicardial gradient (r=0.51; P<0.01). This association remained significant after adjusting for BP, eGFR, and presence of left ventricular hypertrophy. Eventually, patients with CKD also showed higher delay in time to peak cardiac contraction (58±28 versus 37±18 milliseconds; P<0.05).

CONCLUSIONS

A significant proportion of children with CKD show impaired systolic mechanics. Impaired systolic function is characterized by lower radial strain, transmural circumferential gradient, and mild cardiac dyssynchrony. This study suggests that analysis of cardiac strain is feasible in a large multicenter study in children with CKD and provides additional information on cardiac pathophysiology of this high-risk population.

Association between Left Ventricular Postsystolic Shortening and Diastolic Relaxation in Asymptomatic Patients with Systemic Hypertension

BACKGROUND

Few data have existed on myocardial postsystolic shortening (PSS) accounting for left ventricular (LV) diastolic dysfunction in systemic hypertension. We examined this relationship, along with clinical and other cardiac parameters, in asymptomatic patients with hypertension.

METHODS

We analyzed 104 patients on pharmacological treatment for hypertension who had no signs or symptoms of heart failure for conventional and speckle tracking echocardiography. The sum of the postsystolic index for multiple LV segments (total PSI) and global longitudinal strain (GLS) was computed and used as measures for global PSS and myocardial systolic function, respectively. The tissue Doppler e' and the speckle tracking-derived global strain rate during early diastole (e'sr) were obtained as indicators of LV relaxation. The circumferential end-systolic stress was also determined noninvasively and substituted for a measure of myocardial afterload.

RESULTS

Main variables that correlated with the e' and e'sr were shown to be age, LV mass index, left atrial volume index, GLS, and the total PSI. Multivariate analysis including gender, circumferential end-systolic stress, and the use of calcium channel blockers as possible covariates revealed that age (β = -0.29, P = 0.002), total PSI (β = -0.26, P = 0.008), and LV mass index (β = -0.25, P = 0.017) were significant independent determinants of e' and that age (β = -0.34, P < 0.001) and GLS (β = -0.28, P = 0.006) were of e'sr.

CONCLUSIONS

Our findings indicate that while depending on the degree of GLS, PSS may affect diastolic relaxation in patients with asymptomatic, but treated, hypertensive patients.