Left ventricular diastolic dysfunction in the early stage of chronic kidney disease

The role of aetiology in cardiac manifestations of chronic kidney disease: the CPH-CKD ECHO study

PURPOSE

We investigated the associations between cardiac parameters and aetiologies of CKD in an exploratory study.

METHODS

The study population consisted of 883 participants, 174 controls and 709 patients with aetiologies of CKD including diabetic nephropathy/renovascular KD in diabetes mellitus, hypertensive/renovascular nephropathy, tubulointerstitial nephritis, glomerulonephritis/vasculitis, polycystic KD (PKD), and CKD of unknown origin. Echocardiographic measures included left ventricular (LV) ejection fraction, global longitudinal, area, and radial strain, E/e' ratio, and LV mass index. These were compared between each aetiological group and controls in unadjusted and adjusted analysis.

RESULTS

In unadjusted analysis, patients with diabetic nephropathy/renovascular KD in diabetes mellitus, had impaired LV ejection fraction (Median [IQR]: 56% [49.9,60.69] vs. 60.8% [57.7,64.1]), global longitudinal (mean ± SD: 13.1 ± 3.5% vs. 15.5 ± 2.6%), area (24.1 ± 5.8% vs. 28.5 ± 4.2%), and radial strain (36.2 ± 11.2% vs. 44.1 ± 9.7%), and increased LV mass index (89.1 g/m2 [71.8,104.9] vs. 69,0 g/m2 [57.9,80.8]) and E/e' ratio (10.6 [8.5,12.6] vs. 7 [5.8,8.3], p < 0.001 for all) compared with controls. Associations were similar for CKD of unknown origin. Patients with hypertensive/renovascular nephropathy had impaired global longitudinal and area strain, and higher E/e' ratio. Patients with glomerulonephritis/vasculitis had higher LV mass index, while patients with PKD had better global longitudinal strain than controls. All findings remained significant in adjusted analysis, except for the impaired global longitudinal strain in hypertensive/renovascular nephropathy.

CONCLUSION

Glomerulonephritis/vasculitis, hypertensive/renovascular nephropathy, CKD of unknown origin, and diabetic nephropathy/renovascular KD in diabetes mellitus were increasingly associated with adverse cardiac findings, while PKD and tubulointerstitial nephritis were not. Aetiology might play a role regarding the cardiac manifestations of CKD.

Renal and cardiovascular prognostic significance of echocardiographic early diastolic mitral annular velocity in IgA nephropathy

In chronic kidney disease (CKD), as in IgA nephropathy (IgAN), cardiovascular (CV) mortality and morbidity are many times higher than in the general population, and diastolic dysfunction (LVDD) has prognostic significance as well. Tissue Doppler Echocardiography (TDI) is another method for measuring myocardial contractility and determining diastolic dysfunction. 79 IgAN patients (age 46 ± 11 years) with CKD stages 1-3 were investigated and followed for 70 ± 28.7 months. Doppler echocardiography was used to measure the E (early) and A (late) waves, as well as the E wave deceleration time (EDT) during mitral inflow. TDI was used to measure early (Ea) and late (Aa) diastolic velocities (lateral and septal basal wall fragment average). From these, we calculated the E/Ea and Ea/Aa ratios. The primary combined endpoints were total mortality, major CV events, and end-stage renal disease, and the secondary endpoints were cardiovascular or renal (eGFR decreased below 15 ml/min/1.73 m2 or renal replacement therapy was started). Patients with decreased Ea (< 13 cm/s) had significantly more endpoints (20/42 vs. 3/37; p = 0.001) than patients with higher Ea (≥ 13 cm/s). The secondary renal endpoints were also significantly higher (p = 0.004). In a multivariate model, the eGFR showed independent correlation with the E/A ratio (r = 0.466; p < 0.01), EDT (r = - 0.270; p < 0.01), Ea/Aa ratio (r = 0.455; p < 0.01), and decreased Ea (r = 0.544; p < 0.01). Independent factors influencing Ea were only EDT by uni- and multivariate regression but age and albuminuria by logistic regression. Decreased Ea measured by TDI seems to be an eligible factor to predict the prognosis of IgA nephropathy. The decreased Ea may be a helpful parameter to identify high-risk CKD patients.

Left Ventricular Mass Index Predicts Renal Function Decline in Patients with Chronic Kidney Disease

Background and Objectives: Several studies revealed a relation between abnormal cardiac remodeling and glomerular filtration rate (GFR) decline, but there are limited data regarding echocardiographic changes in chronic kidney disease (CKD). This study evaluated the abnormal cardiac structures characterizing patients with CKD, assessing the independent association between echocardiographic parameters and the risk of decline in renal function. Materials and Methods: In total, 160 patients with CKD were studied. All patients underwent an echocardiographic exam and 99mTc-DTPA renal scintigraphy to measure the GFR. After the baseline assessments, patients were followed prospectively for 12 months, or until the endpoint achievement, defined as a worsening in renal function (doubling of baseline serum creatinine, GFR decline ≥25%, the start of dialysis). Results: Patients with GFR values of 34.8 ± 15 mL/min, identifying stages III-IV of CKD, were associated with high levels of left ventricular mass index (LVMi) (101.9 ± 12.2 g/m2), which was related to proteinuria, systolic blood pressure, and pulmonary artery systolic pressure in a multiple regression model. During the observational period, 26% of patients reached the endpoint. Regression analysis revealed LVMi as a predictor of change in renal function after adjusting for kidney and cardiac risk factors. Multiple Cox regression indicated that an increase in LVMi was associated with a 12% increased risk of kidney disease progression (HR: 1.12; 95% CI: 1.04-1.16; p = 0.001). Conclusions: In patients with CKD, high LVMi represents an independent predictor of the progressive decline of the renal function, until the start of renal replacement therapy. Echocardiography can help identify patients at high risk for renal disease worsening in patients with CKD independently of clinical cardiac involvement.

Comparing Left Ventricular Diastolic Function between Peritoneal Dialysis and Non-Dialysis Patients with Stage 5 Chronic Kidney Disease: A Propensity Score-Matched Analysis

Patients with chronic kidney disease (CKD) have a high incidence of left ventricular diastolic dysfunction (LVDD), which increases the risk of heart failure and mortality. We assessed fluid overload as an independent risk factor for LVDD in patients with decreased kidney function and compared its impact on the E/e' ratio as a parameter for assessing left ventricular diastolic functions between patients undergoing continuous ambulatory peritoneal dialysis (CAPD) and those with non-dialysis CKD stage 5 (CKD5) using propensity score matching (PSM). After PSM, 222 patients (CAPD, n = 111; CKD5, n = 111) were included. Fluid balance was assessed using bio-impedance spectroscopy and LVDD was determined by echocardiography based on an E/e' ratio of >15. The CKD5 group had a significantly higher E/e' ratio (p = 0.002), while fluid overload (OH/ECW) did not differ significantly between the groups. In the CAPD group, there were no significant differences in OH/ECW between patients with and without LVDD (p = 0.517). However, in the CKD5 group, patients with LVDD showed a significantly higher OH/ECW (p = 0.001). In a regression analysis investigating factors associated with the E/e' ratio, OH/ECW was not significantly associated with the E/e' ratio in the CAPD group (p = 0.087), but in the CKD5 group, it was independently correlated (p = 0.047). The factors closely associated with LVDD varied depending on dialysis dependence. While fluid overload independently influenced LVDD in non-dialysis patients, it was not statistically significant in patients with CAPD. Early assessment and management of volume status are crucial in addressing LVDD in patients with advanced-stage CKD.

The association between changes in echocardiography and risk of heart failure hospitalizations and death in adults with chronic kidney disease

Adults with chronic kidney disease (CKD) are at increased risk for developing heart failure (HF). However, longitudinal cardiac remodeling in CKD has not been well-characterized and its association with HF outcomes remains unknown. We evaluated the association between change in echocardiographic parameters between baseline and year 4 with the subsequent risk of HF hospitalization and death using Cox proportional hazard models in a landmark analysis of a prospective multicenter CKD cohort. Among 2673 participants, mean ± SD age was 61 ± 11 years, with 45% women, and 56% non-white. A total of 472 hospitalizations for HF and 776 deaths occurred during a median (interquartile range) follow-up duration of 8.0 (6.3-9.1) years. Patients hospitalized for HF experienced larger preceding absolute increases in left ventricular (LV) volumes and decreases in LV ejection fraction. Adverse changes in LV ejection fraction, LV cavity volume, LV mass index, and LV geometry were independently associated with an increased risk of HF hospitalization and death. Among adults with CKD, deleterious cardiac remodeling occurs over a relatively short timeframe and adverse remodeling is associated with increased risk of HF-related morbidity and mortality.

Hypertension and cardiomyopathy associated with chronic kidney disease: epidemiology, pathogenesis and treatment considerations

Chronic kidney disease (CKD) is a complex condition with a prevalence of 10-15% worldwide. An inverse-graded relationship exists between cardiovascular events and mortality with kidney function which is independent of age, sex, and other risk factors. The proportion of deaths due to heart failure and sudden cardiac death increase with progression of chronic kidney disease with relatively fewer deaths from atheromatous, vasculo-occlusive processes. This phenomenon can largely be explained by the increased prevalence of CKD-associated cardiomyopathy with worsening kidney function. The key features of CKD-associated cardiomyopathy are increased left ventricular mass and left ventricular hypertrophy, diastolic and systolic left ventricular dysfunction, and profound cardiac fibrosis on histology. While these features have predominantly been described in patients with advanced kidney disease on dialysis treatment, patients with only mild to moderate renal impairment already exhibit structural and functional changes consistent with CKD-associated cardiomyopathy. In this review we discuss the key drivers of CKD-associated cardiomyopathy and the key role of hypertension in its pathogenesis. We also evaluate existing, as well as developing therapies in the treatment of CKD-associated cardiomyopathy.

Echocardiographic Abnormalities in Autosomal Dominant Polycystic Kidney Disease (ADPKD) Patients

Cardiovascular abnormalities, such as left ventricular hypertrophy and valvular disorders, particularly mitral valve prolapse, have been described as highly prevalent among adult patients with autosomal dominant polycystic kidney disease (ADPKD). The present study aimed to assess echocardiographic parameters in a large sample of both normotensive and hypertensive ADPKD patients, regardless of kidney function level, and evaluate their association with clinical and laboratorial parameters. A retrospective study consisted of the analysis of clinical, laboratorial, and transthoracic echocardiograms data retrieved from the medical records of young adult ADPKD outpatients. A total of 294 patients (120 M/174 F, 41.0 ± 13.8 years old, 199 hypertensive and 95 normotensive) with a median estimated glomerular filtration rate (eGFR) of 75.5 mL/min/1.73 m² were included. The hypertensive group (67.6%) was significantly older and exhibited significantly lower eGFR than the normotensive one. Increased left ventricular mass index (LVMI) was seen in 2.0%, mitral valve prolapse was observed in 3.4%, mitral valve regurgitation in 15.3%, tricuspid valve regurgitation in 16.0%, and aortic valve regurgitation in 4.8% of the whole sample. The present study suggested that the prevalence of mitral valve prolapse was much lower than previously reported, and increased LVMI was not seen in most adult ADPKD patients.

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 value of echocardiography for heart failure and death in adults with chronic kidney disease

BACKGROUND

Adults with chronic kidney disease (CKD) are at increased risk of heart failure (HF) morbidity and mortality. Despite well-characterized abnormalities in cardiac structure in CKD, it remains unclear how to optimally leverage echocardiography to risk stratify CKD patients.

METHODS

We evaluated associations between echocardiographic parameters and risk of HF hospitalization and death using Cox proportional hazard models and forward selection with integrated discrimination improvement (IDI).

RESULTS

The study included 3,505 participants enrolled in the Chronic Renal Insufficiency Cohort (CRIC) study. Mean age was 59 ± 11 years, HF prevalence was 10%, and mean left ventricular (LV) ejection fraction (LVEF) was 54 ± 9%. During median 11 (interquartile range: 8-12) years of follow-up, event rates per 100-person years for HF hospitalizations and death, respectively, were 9.4 (95% Confidence Interval [CI]: 7.9-11.3) and 8.9 (95% CI: 7.6-10.5) for participants with LVEF <40%, 3.5 (95% CI: 3.0-4.2) and 4.6 (95% CI: 4.0-5.2) for patients with LVEF 40% to 49%, and 1.9 (95% CI: 1.7-2.1) and 3.1 (95% CI: 2.9-3.3) for patients with LVEF >50%. The rate of HF hospitalizations and deaths increased with lower eGFR across all LVEF categories. LV mass index, LVEF, and LV geometry had the strongest association with outcomes but provided modest incremental prognostic value to a baseline clinical model (IDI = 0.14 and ΔAUC = 0.017 for HF hospitalization, IDI = 0.12 and ΔAUC = 0.008 for death).

CONCLUSIONS

Baseline echocardiographic parameters are independently associated with increased risk of subsequent HF morbidity and mortality but provide only marginal incremental prognostic utility beyond clinical characteristics in the setting of CKD.

Association of Left Ventricular Diastolic Dysfunction With Cardiovascular Outcomes in Patients With Pre-dialysis Chronic Kidney Disease: Findings From KNOW-CKD Study

Background

The impact of left ventricular diastolic dysfunction (LVDD) on cardiovascular (CV) outcomes in patients with pre-dialysis chronic kidney disease (CKD) has been rarely unveiled. We here investigated the association of LVDD with CV outcomes and all-cause mortality in patients with pre-dialysis CKD.

Methods

A total of 2,135 patients with pre-dialysis CKD from the Korean Cohort Study for Outcomes in Patients With Chronic Kidney Disease (KNOW-CKD) cohort were dichotomized by the absence or presence of LVDD, which was defined as the ratio of the early transmitral blood flow velocity to early diastolic velocity of the mitral annulus (E/e′) &gt; 14.

Results

Cox regression analysis revealed that LVDD was significantly associated with increased risk of composite CV events [adjusted hazard ratio (HR) 2.194, 95% confidence interval (CI) 1.486–3.240] and all-cause mortality (adjusted HR 1.830, 95% CI 1.168–2.869). Restricted cubic splines visualized stringent linear correlations of E/e′ with both composite CV events and all-cause mortality. In the sensitivity analysis only including the subjects with left ventricular ejection fraction ≥ 50%, LVDD was still significantly associated with adverse CV outcomes (adjusted HR 1.984, 95% CI 1.325–3.000) and all-cause mortality (adjusted HR 1.727, 95% CI 1.083–2.754), suggesting that the impact of LVDD on the outcomes in patients with CKD is independent of LV systolic function. Subgroup analyses revealed that the associations were not modified by various clinical contexts, such as age, sex, burden of comorbid conditions, body mass index, estimated glomerular filtration rate, and albuminuria.

Conclusion

LVDD is independently associated with adverse CV outcomes and all-cause mortality in patients with pre-dialysis CKD.

Associations Between Myocardial Diastolic Dysfunction and Cardiovascular Mortality in Chronic Kidney Disease: A Large Single-Center Cohort Study

BACKGROUND

The clinical burden and prognostic role of diastolic dysfunction (DD), based on the latest American Society of Echocardiography (ASE) 2016 guidelines, remains unclear in patients with chronic kidney disease (CKD). Moreover, risk mapping of concomitant systolic dysfunction and DD to evaluate the hazard of cardiovascular (CV) mortality in CKD remains unexplored.

METHODS

This retrospective cohort study identified 20,257 adult patients who underwent comprehensive echocardiography between 2008 and 2016 at a tertiary medical center in central Taiwan. The patients were stratified by CKD stage, and the 3-year CV mortality risk in each CKD stratum was estimated through multivariable Cox proportional hazard modeling using left ventricular ejection fraction (LVEF) and DD grades based on ASE 2016 guideline as the main risk factors.

RESULTS

Compared with patients with CKD stages 1 and 2, those with CKD stages 4 and 5 had a significantly lower LVEF and more severe DD. Both LVEF (LVEF < 40% vs. ≥ 60%; adjusted hazard ratio [aHR] 3.17, 95% confidence interval [CI] 2.54-3.97) and DD grade (severe DD vs. normal diastolic function; aHR 3.33, 95% CI 2.33-4.76) were independently associated with 3-year CV mortality in the entire study population and had comparable effect sizes. The corresponding aHRs further increased to 4.20 (2.45-7.21) and 4.54 (2.20-9.38) in patients with CKD stages 4 and 5. Systolic and diastolic dysfunction demonstrated mutually augmentative effects on CV mortality.

CONCLUSIONS

These findings suggest that the current practice of cardioprotection for patients with CKD should be prioritized at an early stage along with conventional nephroprotection.

Effect of diabetes mellitus on markers of left ventricular dysfunction in chronic kidney disease

OBJECTIVES

To identify markers of left ventricular dysfunction in chronic kidney disease (CKD) and the effects of diabetes mellitus on them.

METHODS

This was a cross sectional study of 200 consecutive chronic kidney disease patients (stage III-V). Echocardiographic assessment of left ventricular function including left ventricular ejection fraction (LVEF), left ventricular mass index (LVMI), left atrial volume, grade of diastolic dysfunction, E/E', left and right ventricular myocardial performance indices (LVMPI, RVMPI) were compared between diabetic and non-diabetic CKD.

RESULTS

LVMI significantly increased with increasing stage of CKD (p < 0.001) in both diabetics (158.82 ± 48.76 gm/m2 in stage III to 201.06 ± 63.62 gm/m2 in stage V) and non-diabetics (133.14 ± 43.06 gm/m2 stage III to 196.24 ± 58.75 gm/m2 in stage V). This was significantly higher among diabetics of similar CKD stage compared to non-diabetics (p = 0.001). The LVEF worsened with increasing stage of CKD (p = 0.002) and was significantly reduced in diabetic patients (LVEF 61.96 ± 8.48 % in stage III CKD to 51.62 ± 13.45 % in stage V CKD) (p < 0.001). Diastolic dysfunction (Grades ≥2) and LA volume increased significantly with stage of CKD (p < 0.001) and was higher among diabetics (p = 0.048). Pulmonary artery systolic pressure (PASP) increased with increasing stage of CKD (p < 0.001), and was higher among diabetics (p = 0.035). E/E' worsened significantly with increasing stage of CKD and was also significantly higher in diabetics (p < 0.001). LVMPI (p < 0.001) and RVMPI (p < 0.001) were significantly reduced with worsening stage of CKD and in diabetics.

CONCLUSION

Advancing CKD stage was linearly associated with progressive left ventricular dysfunction which was significantly greater in diabetics.

Fibrosis, the Bad Actor in Cardiorenal Syndromes: Mechanisms Involved

Cardiorenal syndrome is a term that defines the complex bidirectional nature of the interaction between cardiac and renal disease. It is well established that patients with kidney disease have higher incidence of cardiovascular comorbidities and that renal dysfunction is a significant threat to the prognosis of patients with cardiac disease. Fibrosis is a common characteristic of organ injury progression that has been proposed not only as a marker but also as an important driver of the pathophysiology of cardiorenal syndromes. Due to the relevance of fibrosis, its study might give insight into the mechanisms and targets that could potentially be modulated to prevent fibrosis development. The aim of this review was to summarize some of the pathophysiological pathways involved in the fibrotic damage seen in cardiorenal syndromes, such as inflammation, oxidative stress and endoplasmic reticulum stress, which are known to be triggers and mediators of fibrosis.

Cardiac functions in children with steroid-sensitive nephrotic syndrome

BACKGROUND

The aim of the present study was to evaluate the presence of cardiac systolic and diastolic dysfunction in pediatric patients with steroid-sensitive nephrotic syndrome (NS).

METHODS

The study population consisted of 19 patients with debut-relapse of NS aged 1-18 years and 30 sex and age-matched healthy controls. Blood and urine samples, two M-mode conventional echocardiograms and tissue Doppler velocity imaging were evaluated in both attack and remission periods.

RESULTS

With regard to conventional pulse wave Doppler (cPWD), steroid-sensitive NS patients (both in debut / relapse and in remission periods) had a higher peak of late diastolic flow velocities (A peak), and patients in debut / relapse had a lower E/A ratio than the control group, indicating diastolic dysfunction (overall P = 0.003 and P = 0.006, respectively). Based on tissue Doppler velocity imaging echocardiography results, patients in debut/relapse had a higher A' and a lower E'/A' ratio (overall P < 0.001 and P = 0.001, respectively). There was also a significant difference in the cPWD E/TDI E' ratio between the patients showing an increased cPWD E/TDI E' ratio in remission periods compared to in debut/relapse periods (P = 0.09). The albumin levels were positively correlated with E'/A' and E/ E' ratio (r = 0.609; P = 0.007, r = 0.472; P = 0.041 respectively).

CONCLUSIONS

Systolic cardiac functions are preserved but diastolic functions are affected in steroid-sensitive NS patients both in debut/relapse and in remission periods in a relatively short time. The persistence of left ventricular (LV) dysfunction during the remission period requires special attention during the follow up for early detection of cardiac abnormalities.

Aerobic exercise capacity is maintained over a 5-year period in mild-to-moderate chronic kidney disease: a longitudinal study

Background

Aerobic exercise capacity is reduced in non-dialysis chronic kidney disease (CKD), but the magnitude of changes in exercise capacity over time is less known. Our main hypothesis was that aerobic ExCap would decline over 5 years in individuals with mild-to-moderate CKD along with a decline in renal function. A secondary hypothesis was that such a decline in ExCap would be associated with a decline in muscle strength, cardiovascular function and physical activity.

Methods

We performed a 5-year-prospective study on individuals with mild-to-moderate CKD, who were closely monitored at a nephrology clinic. Fiftytwo individuals with CKD stage 2–3 and 54 age- and sex-matched healthy controls were included. Peak workload was assessed through a maximal cycle exercise test. Muscle strength and lean body mass, cardiac function, vascular stiffness, self-reported physical activity level, renal function and haemoglobin level were evaluated. Tests were repeated after 5 years. Statistical analysis of longitudinal data was performed using linear mixed models.

Results

Exercise capacity did not change significantly over time in either the CKD group or controls, although the absolute workloads were significantly lower in the CKD group. Only in a CKD subgroup reporting low physical activity at baseline, exercise capacity declined. Renal function decreased in both groups, with a larger decline in CKD (p = 0.05 between groups). Peak heart rate, haemoglobin level, handgrip strength, lean body mass and cardiovascular function did not decrease significantly over time in CKD individuals.

Conclusions

On a group level, aerobic exercise capacity and peak heart rate were maintained over 5 years in patients with well-controlled mild-to-moderate CKD, despite a slight reduction in glomerular filtration rate. In line with the maintained exercise capacity, cardiovascular and muscular function were also preserved. In individuals with mild-to-moderate CKD, physical activity level at baseline seems to have a predictive value for exercise capacity at follow-up.

Heart failure and left ventricular dysfunction in older patients with chronic kidney disease: the China Hypertension Survey (2012-2015)

Background

Heart failure (HF) is a leading cause of hospitalization and mortality for older chronic kidney disease (CKD) patients. However, the epidemiological data is scarce. We aimed to determine the prevalence of left ventricular (LV) dysfunction and HF, and to explore the risk factors for HF among those patients.

Methods

This is a cross-sectional analysis of the China Hypertension Survey conducted between October 2012 and December 2015. A total of 5, 808 participants aged ≥ 65 years were included in the analysis. Self-reported history of HF and any other cardiovascular diseases was acquired. 2-D and Doppler echocardiography were used to assess LV dysfunction. CKD was defined as either estimated glomerular filtration rate (eGFR) < 60 mL/min per 1.73 m² or urinary albumin to creatinine ratio (ACR) ≥ 30 mg/g.

Results

Among CKD patients aged ≥ 65 years, the weighted prevalence of HF, heart failure with preserved ejection fraction (HFpEF), heart failure with mid-range ejection fraction (HFmrEF), and heart failure with reduced ejection fraction (HFrEF) was 4.8%, 2.5%, 0.8%, and 1.7%, respectively. The weighted prevalence of HF was 5.0% in patients with eGFR < 60 mL/min per 1.73 m², and was 5.9% in patients with ACR ≥ 30 mg/g. The prevalence of LV systolic dysfunction was 3.1%, and while it was 8.9% for moderate/severe diastolic dysfunction. Multivariate analysis showed that smoking was significantly associated with the risk of HF. Furthermore, age, smoking, and residents in rural areas were significantly associated with a risk of LV diastolic dysfunction.

Conclusions

The prevalence of HF and LV dysfunction was high in older patients with CKD, suggesting that particular strategies will be required.

Longitudinal changes of left and right cardiac structure and function in patients with end-stage renal disease on replacement therapy

BACKGROUND

Few data are available regarding longitudinal changes of cardiac structure and function in end-stage chronic kidney disease (CKD). Aim of the present study is to describe serial echocardiographic findings in a cohort of dialyzed CKD patients.

METHODS

In this retrospective longitudinal study, we included n = 120 dialyzed CKD patients who underwent at least 2 echocardiograms either 1, 2 or 3 years apart. After baseline echocardiogram, n = 112 had a further examination at year 1, n = 76 at year 2 and n = 45 at year 3. Echocardiographic examination included Tissue Doppler Imaging of both left (LV) and right (RV) ventricle.

RESULTS

LV geometry and LV mass index did not significantly change over time. RV progressively dilated (mean change +1.3 mm, +1.1 mm and +3.1 mm at year 1, 2 and 3 respectively, p = 0.002, adjusted p = 0.003). Tissue Doppler parameters showed significant changes with regard to both LV (mean change of E/E' +0.7, +1.3, +1.7 at year 1, 2 and 3 respectively p<0.001, adjusted p = 0.079) and RV (mean change of S wave (cm/sec) -1, -1.7, -2 at year 1, 2 and 3 respectively, p <0.001, adjusted p = 0.041). Decrease of RV S wave negatively correlated with E/E' changes (r=-0.303, p = 0.002; r=-0.246, p = 0.049; r=-0.265, p = 0.089; at year 1, 2 and 3 respectively). LV ejection fraction (LVEF) progressively declined (p = 0.034, adjusted p = 0.140), albeit being significant lower against baseline only at year 3 (mean change -4.3%, p<0.05).

CONCLUSIONS

In dialyzed CKD patients we observed parallel worsening of LV diastolic and RV systolic function accompanied by RV dilation. LVEF decreased less sharply.

Fluid overload is a determinant for cardiac structural and functional impairments in type 2 diabetes mellitus and chronic kidney disease stage 5 not undergoing dialysis

BACKGROUND

Fluid overload is common in patients with diabetes and chronic kidney disease (DM and CKD; DMCKD) and can lead to structural and functional cardiac abnormalities including left ventricular hypertrophy (LVH) and left ventricular diastolic dysfunction (LVDD). Fluid overload represents a crucial step in the pathophysiological pathways to chronic heart failure in patients with end-stage renal disease. We evaluated the impact of fluid overload on cardiac alterations in patients with diabetes and non-dialysis-dependent CKD stage 5 (DMCKD5-ND) without intrinsic heart disease.

METHODS

Bioimpedance spectroscopy, echocardiography, and N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) measurement were performed in 135 consecutive patients on the same day. Patients were divided into groups by tertiles of overhydration/extracellular water (OH/ECW) per bioimpedance spectroscopy.

RESULTS

Fluid balance markers including OH/ECW and NT-proBNP were significantly higher in the LVDD+LVH group. OH/ECW and its exacerbation were positively associated with the ratio between early mitral inflow and annular early diastolic velocities (E/e' ratio) and left ventricular mass index (LVMI). The prevalence of LVH progressively increased across increasing tertiles of OH/ECW. In multiple regression analyses, OH/ECW as a continuous and categorical variable was independently associated with the E/e' ratio and LVMI after adjustment for multiple confounding factors.

CONCLUSIONS

Fluid overload was independently associated with LVDD and LVH in patients with DMCKD5-ND. Our study suggests that structural and functional cardiac abnormalities and volume status should be evaluated simultaneously in patients with early-stage DMCKD rather than only DMCKD5-ND, in addition to intensive blood pressure and glycemic control, regardless of evident cardiovascular disease.

Evolving concepts in the pathogenesis of uraemic cardiomyopathy

The term uraemic cardiomyopathy refers to the cardiac abnormalities that are seen in patients with chronic kidney disease (CKD). Historically, this term was used to describe a severe cardiomyopathy that was associated with end-stage renal disease and characterized by severe functional abnormalities that could be reversed following renal transplantation. In a modern context, uraemic cardiomyopathy describes the clinical phenotype of cardiac disease that accompanies CKD and is perhaps best characterized as diastolic dysfunction seen in conjunction with left ventricular hypertrophy and fibrosis. A multitude of factors may contribute to the pathogenesis of uraemic cardiomyopathy, and current treatments only modestly improve outcomes. In this Review, we focus on evolving concepts regarding the roles of fibroblast growth factor 23 (FGF23), inflammation and systemic oxidant stress and their interactions with more established mechanisms such as pressure and volume overload resulting from hypertension and anaemia, respectively, activation of the renin-angiotensin and sympathetic nervous systems, activation of the transforming growth factor-β (TGFβ) pathway, abnormal mineral metabolism and increased levels of endogenous cardiotonic steroids.

High Fibroblast Growth Factor 23 concentrations in experimental renal failure impair calcium handling in cardiomyocytes

The overwhelming majority of patients with chronic kidney disease (CKD) die prematurely before reaching end‐stage renal disease, mainly due to cardiovascular causes, of which heart failure is the predominant clinical presentation. We hypothesized that CKD‐induced increases of plasma FGF23 impair cardiac diastolic and systolic function. To test this, mice were subjected to 5/6 nephrectomy (5/6Nx) or were injected with FGF23 for seven consecutive days. Six weeks after surgery, plasma FGF23 was higher in 5/6Nx mice compared to sham mice (720 ± 31 vs. 256 ± 3 pg/mL, respectively, P = 0.034). In cardiomyocytes isolated from both 5/6Nx and FGF23 injected animals the rise of cytosolic calcium during systole was slowed (−13% and −19%, respectively) as was the decay of cytosolic calcium during diastole (−15% and −21%, respectively) compared to controls. Furthermore, both groups had similarly decreased peak cytosolic calcium content during systole. Despite lower cytosolic calcium contents in CKD or FGF23 pretreated animals, no changes were observed in contractile parameters of cardiomyocytes between the groups. Expression of calcium handling proteins and cardiac troponin I phosphorylation were similar between groups. Blood pressure, the heart weight:tibia length ratio, α‐MHC/β‐MHC ratio and ANF mRNA expression, and systolic and diastolic function as measured by MRI did not differ between groups. In conclusion, the rapid, CKD‐induced rise in plasma FGF23 and the similar decrease in cardiomyocyte calcium transients in modeled kidney disease and following 1‐week treatment with FGF23 indicate that FGF23 partly mediates cardiomyocyte dysfunction in CKD.

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.

Percutaneous transluminal angioplasty for central venous stenosis or occlusion in hemodialysis patients

The objectives of central venous percutaneous transluminal angioplasty are to dilate the venous lesion and to extend the life of arteriovenous fistula for hemodialysis. It is reasonable to perform percutaneous transluminal angioplasty for central venous lesions if this interventional therapy is required to maintain stable dialysis therapy. However, the presence of large fresh thrombus at central venous lesion site represents a contraindication to percutaneous transluminal angioplasty unless the thrombus can first be removed by thrombectomy. Balloon angioplasty is a basic treatment for central venous lesion, but stent implantation is sometimes required. The self-expandable or balloon-expandable stent is chosen by the lesion location and characteristics. The lesion in subclavian vein is generally treated by self-expandable stent and right brachiocephalic vein is treated by balloon-expandable stent. The organic lesion of innominate vein with plaque is treated by self-expandable stent. Note that the innominate venous stenosis is sometimes caused by compression between the right brachiocephalic artery and the sternum, and this lesion is treated by balloon-expandable stent because the radial force of balloon-expandable stent is stronger than self-expandable stent. It is important to understand the indication and stent selection for central venous percutaneous transluminal angioplasty.

Renal function monitoring in heart failure - what is the optimal frequency? A narrative review

The second most common cause of hospitalization due to adverse drug reactions in the UK is renal dysfunction due to diuretics, particularly in patients with heart failure, where diuretic therapy is a mainstay of treatment regimens. Therefore, the optimal frequency for monitoring renal function in these patients is an important consideration for preventing renal failure and hospitalization. This review looks at the current evidence for optimal monitoring practices of renal function in patients with heart failure according to national and international guidelines on the management of heart failure (AHA/NICE/ESC/SIGN). Current guidance of renal function monitoring is in large part based on expert opinion, with a lack of clinical studies that have specifically evaluated the optimal frequency of renal function monitoring in patients with heart failure. Furthermore, there is variability between guidelines, and recommendations are typically nonspecific. Safer prescribing of diuretics in combination with other antiheart failure treatments requires better evidence for frequency of renal function monitoring. We suggest developing more personalized monitoring rather than from the current medication-based guidance. Such flexible clinical guidelines could be implemented using intelligent clinical decision support systems. Personalized renal function monitoring would be more effective in preventing renal decline, rather than reacting to it.

Association between E/e´ ratio and fluid overload in patients with predialysis chronic kidney disease

Background

Chronic fluid overload is common in patients with chronic kidney disease (CKD) and can with time lead to diastolic dysfunction and heart failure. We investigated whether markers of fluid status, such as NT-proBNP and bioimpedance spectroscopy (BIS), can predict echocardiographic findings of diastolic dysfunction in non-dialysis CKD5 patients.

Methods

BIS, echocardiography, and measurement of serum NT-proBNP were performed in patients with non-dialysis CKD stage 5 at a single study visit. E/e´ ratio reflect mean LV diastolic pressure and a ratio greater than 15 was used as a definition of diastolic dysfunction.

Results

Eighty-four patients were analyzed. Forty-six patients (54.76%) had E/e´ ratio ≤15 and 38 patients (45.24%) had E/e´ > 15 (diastolic dysfunction). Patients with E/e´>15 had significantly higher serum NT-proBNP (14,650 pg/mL) than patients with to E/e´≤15 (4,271 pg/mL) and had more overhydration (OH), 5.1 liters compared to 2.4 liters. The cut-off values predicting diastolic dysfunction were found to be 2,797 pg/mL for NT-proBNP and 2.45 liters for OH.

Conclusions

Regular monitoring of fluid status by BIS and NT-proBNP can be used to find patient with risk of developing diastolic dysfunction. Treatments to correct fluid overload may reduce the risk of developing diastolic dysfunction and improve cardiovascular outcome in patients with CKD.

Cardiovascular alterations do exist in children with stage-2 chronic kidney disease

BACKGROUND

Cardiovascular disease (CVD) is an important complication of chronic kidney disease (CKD) in children. However, it is not well known when and how cardiovascular alterations start.

METHODS

This cross-sectional, controlled study consisted of 25 patients and 28 healthy controls. 24-h ambulatory blood pressure monitoring, aortic pulse wave velocity (aPWV), carotid intima-media thickness (cIMT) and carotid distensibility (distensibility coefficient and β stiffness index), and echocardiography were assessed to evaluate CVD. Routine biochemical parameters, fibroblast growth factor-23 (FGF23) and high sensitive C- reactive protein were measured to determine cardiovascular risk factors.

RESULTS

Hypertension was found in 12 patients (48 %). Patients had higher FGF23 levels and aPWV-standard deviation score (SDS) as compared to the controls (p = 0.003 and p = 0.002, respectively). Aortic PWV-SDS was predicted by increased daytime systolic blood pressure load (β = 0.512, p = 0.009, R ² = 0.262). Neither cIMT nor distensibility differed between the groups; however, older age and high level of FGF23 were independent predictors of β stiffness index in patients (β = 0.507, p = 0.005, R ² = 0.461 and β = 0.502, p = 0.005, R ² = 0.461, respectively). As compared to controls, patients had worse left ventricular diastolic function [lower E/A ratio p = 0.006) and increased left atrial dimension (p < 0.001)].

CONCLUSIONS

Cardiovascular deteriorations appear in children with stage-2 CKD. Good control of BP and decreasing the level of FGF23 may be useful to slow down the progression of cardiovascular complications.

Left Ventricular Global Longitudinal Strain (GLS) Is a Superior Predictor of All-Cause and Cardiovascular Mortality When Compared to Ejection Fraction in Advanced Chronic Kidney Disease

Background

Echocardiographic global longitudinal strain (GLS) is increasingly recognised as a more effective technique than conventional ejection fraction (EF) in detecting subtle changes in left ventricular (LV) function. This study investigated the prognostic value of GLS over EF in patients with advanced Chronic Kidney Disease (CKD).

Methods

The study included 183 patients (57% male, 63% on dialysis) with CKD stage 4, 5 and 5Dialysis (D). 112 (61%) of patients died in a follow up of 7.8 ± 4.4 years and 41% of deaths were due to cardiovascular (CV) disease. GLS was calculated using 2-dimensional speckle tracking and EF was measured using Simpson’s biplane method. Cox proportional hazard models were used to assess the association of measures of LV function and all- cause and CV mortality.

Results

The mean GLS at baseline was -13.6 ± 4.3% and EF was 45 ± 11%. GLS was a significant predictor of all-cause [Hazard Ratio (HR) 1.09 95%; Confidence Interval (CI) 1.02–1.16; p = 0.01] and CV mortality (HR 1.16 95%; CI 1.04–1.30; p = 0.008) following adjustment for relevant clinical variables including LV mass index (LVMI) and EF. GLS also had greater predictive power for both all- cause and CV mortality compared to EF. Impaired GLS (>-16%) was associated with a 5.6-fold increased unadjusted risk of CV mortality in patients with preserved EF.

Conclusions

In this cohort of patients with advanced CKD, GLS is a more sensitive predictor of overall and CV mortality compared to EF. Studies of larger populations in CKD are required to confirm that GLS provides additive prognostic value in patients with preserved EF.

Heart function disturbances in chronic kidney disease - echocardiographic indices

INTRODUCTION

In chronic kidney disease (CKD) patients left ventricular (LV) diastolic dysfunction occurs frequently and is associated with heart failure (HF) and higher mortality. Left ventricular systolic dysfunction is associated with coronary artery disease (CAD) and is a major determinant of prognosis. The aim of this study was to assess indices of LV diastolic dysfunction in CKD patients.

MATERIAL AND METHODS

Study included 118 CKD patients. All patients underwent transthoracic echocardiography. Diastolic function based on E and A, E/A ratio and pulmonary vein flow velocities as well as EF%, deceleration time, RA, LA volume were assessed. In dialysis patients examination was carried out before and after dialysis.

RESULTS

In CKD patients the stage of renal failure was associated with the significant increase in LV mass (268.0 ±47.6 CKD I/II vs. 432.7 ±122.4 CKD V/dialysis, p < 0.0001), systolic LV (37.3 ±4.5 vs. 51.2 ±8.9, p < 0.0001) and diastolic LV (CKD I-II 44.7 ±4.1 vs. CKD III 48.5 ±6.7 vs. CKD IV 47.1 ±5.6; p = 0.004) dimensions and in the size of the LA (40.4 ±2.0 vs. 41.9 ±2.7 vs. 42.3 ±3.2 vs. 44.8 ±3.1; p < 0.0001). The increase the E/E' ratio between groups of patients (6.7 ±1.5 vs. 8.9 ±2.4 vs. 11.5 ±4.0 vs. 13.5 ±5.0; p < 0.0001) was seen in this study. The reduction in deceleration time (247.2 ±34.5 in CKD I/II vs. 197.4 ±61.0 in CKD IV, p = 0.0005) along with the decrease in estimated glomerular filtration rate was also observed in this study.

CONCLUSIONS

Early identification of factors involved is necessary to prevent this devastating process. Many indexes of contractility are used and each of them has imperfections. It seems that TVI, E, E/A and E/E' are good instruments for the early detection of left ventricular hypertrophy and diastolic dysfunction.

Echocardiographic changes in patients with stage 3-5 chronic kidney disease and left ventricular diastolic dysfunction

BACKGROUND

Left ventricular (LV) diastolic dysfunction in chronic kidney disease (CKD) patients frequently leads to the development of congestive heart failure. We evaluated changes in echocardiographic parameters among CKD patients with LV diastolic dysfunction.

METHODS

We examined 70 ambulatory patients with CKD at stages 3-5 and 26 patients without CKD as a control group. Standard echocardiography and tissue Doppler imaging were performed on all patients. Patients with CKD were divided into two groups according to the results of lateral mitral early diastolic velocity (EmLVlat): a group with diastolic dysfunction (DD group; EmLVlat <8 cm/s) and a group without diastolic dysfunction (WDD group; EmLVlat ≥8 cm/s).

RESULTS

Compared to the patients in the WDD group, those in the DD group were characterized by lower values of mitral annular plane systolic excursion [MAPSE; 13 (11-17) vs. 14 (11-16) mm, p < 0.0001] and lateral mitral annular systolic velocity [SmLVlat; 7 (5-14) vs. 8 (5-13) cm/s, p = 0.006]. The area under the receiver operating characteristic (ROC) curve of the MAPSE level for the detection of LV diastolic dysfunction was 0.801 [95% CI 0.684-0.890, p < 0.0001], whereas a ROC-derived MAPSE value of ≤13 mm was characterized by a sensitivity of 84.4% and a specificity of 75.8% for diagnosing LV diastolic dysfunction. The only independent variable predicting LV diastolic dysfunction was MAPSE [OR = 0.39; 95% CI 0.21-0.74, p = 0.003].

CONCLUSION

We showed that reduced MAPSE, but not SmLVlat, is an independent predictive factor for LV diastolic dysfunction in CKD patients.

Associations of pulse pressure index with left ventricular filling pressure and diastolic dysfunction in patients with chronic kidney disease

BACKGROUND

Patients with chronic kidney disease (CKD) often have poor vascular compliance and poor left ventricular diastolic dysfunction (LVDD). The pulse pressure index (PPI) defined as ((systolic blood pressure - diastolic blood pressure)/systolic blood pressure) reflects vascular compliance. Vascular compliance is reportedly associated with left ventricular diastolic function. This study of CKD patients investigated whether PPI correlates with the ratio of transmitral E wave velocity (E) to early diastole mitral annulus velocity (Ea) or with LVDD.

METHODS

This study enrolled 511 CKD patients who had been referred for echocardiographic examination. Blood pressure was automatically measured with an ABI-form device. The LVDD was defined as E-to-transmitral A wave velocity ratio of ≥0.9, Ea <8 cm/s, or E/Ea ≥15.

RESULTS

Compared with those with E/Ea <15, patients with E/Ea ≥15 had significantly higher systolic blood pressure, pulse pressure, and PPI (all P < 0.001). Multivariable analysis showed that PPI was independently associated with E/Ea (unstandardized coefficient β = 1.348; P < 0.001) and with LVDD (odds ratio = 1.441 per 0.064 increase; P < 0.001).

CONCLUSIONS

This study showed that increased PPI significantly correlates with elevated E/Ea and LVDD in CKD patients. Because PPI can be rapidly acquired during blood pressure measurement, it may be helpful for identifying CKD patients with a high left ventricular filling pressure and LVDD.

Left ventricular diastolic dysfunction by tissue Doppler echocardiography in pediatric chronic kidney disease

BACKGROUND

Myocardial dysfunction is common in chronic kidney disease (CKD) and related to poor outcomes. New non-invasive methods to assess cardiac function have been introduced, but comparative studies evaluating their clinical usefulness in pediatric CKD are lacking. We studied left ventricular (LV) function in pediatric CKD and renal transplant patients, comparing conventional pulse-wave Doppler echocardiography (cPWD) with newer tissue Doppler imaging (TDI) and relating the results to known cardiovascular risk factors.

METHODS

The study included 34 children/adolescents with CKD stages 2-5, 44 renal transplant patients and 19 patients with a normal renal function. The mean age was 11.4 (range 0.8-18.8) years.

RESULTS

Both patient groups had significantly lower LV diastolic function than those with a normal renal function. The most sensitive determinants were TDI E'/A' and cPWD E/TDI E' ratios. In a stepwise linear regression analysis, high blood pressure, young age and the presence of albuminuria all independently predicted LV diastolic function.

CONCLUSIONS

Our study confirms the high prevalence of LV diastolic dysfunction in pediatric CKD patients and following renal transplantation, where TDI appears to be more sensitive than cPWD in assessing early myocardial dysfunction. Our results also underline the importance of preventive measures, such as rigorous blood pressure control, in pediatric CKD.

Ratio of transmitral E-wave velocity to early diastole mitral annulus velocity with cardiovascular and renal outcomes in chronic kidney disease

BACKGROUND/AIMS

Impaired left ventricular diastolic function and increased left ventricular filling pressure are frequently noted in patients with chronic kidney disease (CKD), even in early stages. The association of increased left ventricular filling pressure with cardiovascular and renal outcomes remains uncertain in CKD. This study is designed to assess whether the ratio of transmitral E-wave velocity (E) to early diastole mitral velocity (Ea) is associated with cardiovascular events and progression to dialysis in patients with CKD stages 3-5.

METHODS

This longitudinal study enrolled 356 predialysis CKD patients. Cardiovascular events were defined as cardiovascular death, hospitalization for unstable angina, nonfatal myocardial infarction, ventricular tachycardia, hospitalization for congestive heart failure, transient ischemia attack, and stroke. The renal endpoint was defined as commencement of dialysis. The relative cardiovascular events and renal endpoints risks were analyzed by Cox regression methods.

RESULTS

The high E/Ea was independently associated with old age, cerebrovascular disease, congestive heart failure, high systolic blood pressure, hypertriglyceridemia, low hemoglobin, proteinuria, and worse echocardiographic profiles. Besides, the high E/Ea increased the risk of cardiovascular events (hazard ratio (HR) 1.067; 95% confidence interval (CI) 1.017-1.119; p = 0.008) and progression to dialysis (HR 1.042; 95% CI 1.000-1.085; p = 0.048).

CONCLUSIONS

Our study in patients of CKD stages 3-5 demonstrated the high E/Ea was associated with increased cardiovascular events and progression to dialysis. Assessment of the E/Ea by Doppler echocardiography is useful for predicting the risk of adverse cardiovascular and renal outcomes in CKD patients.

Impaired renal function is a major determinant of left ventricular diastolic dysfunction: assessment by stress myocardial perfusion imaging

Objective

Relationships between myocardial scintigraphic parameters and renal function have not been fully determined. We investigated correlations between estimated glomerular filtration rate (eGFR) and left ventricular (LV) diastolic function using stress electrocardiographic (ECG)-gated myocardial single photon emission computed tomography (SPECT).

Methods

We enrolled 136 consecutive patients with suspected coronary artery disease (CAD) who were assessed using technetium-99m stress ECG-gated myocardial SPECT. We evaluated SPECT images using 17-segment defect scores graded on a 5-point scale, summed stress score, summed rest score and summed difference score (SDS). The parameters for assessing LV diastolic function were peak filling rate (PFR), 1/3 mean filling rate and time to peak filling. The CAD was defined as SDS ≥2. Chronic kidney disease (CKD) was defined as eGFR <60 mL/min/1.73 m². Patients were assigned to the following four groups (no CAD/no CKD: control group, n = 68; CAD/no CKD: CAD group, n = 24; no CAD/CKD: CKD group, n = 34; CAD/CKD: CAD + CKD group, n = 10).

Results

The PFR was significantly impaired after stress in the CKD and CAD + CKD groups compared with controls (p < 0.001 for both). Furthermore, PFR at rest positively correlated with eGFR (r = 0.29, p < 0.001) and inversely correlated with SDS (r = −0.18, p < 0.05). Multivariate stepwise regression analysis independently associated eGFR with PFR (β coefficient = 0.260, p = 0.002).

Conclusions

Our data suggest that impaired renal function is a significant determinant of LV diastolic dysfunction in patients with suspected CAD.

Plasma adrenomedullin and subclinical cardiorenal syndrome in patients with type 2 diabetes mellitus

OBJECTIVE

To evaluate whether plasma adrenomedullin is involved in the previously reported significant inverse correlation between left ventricular (LV) end-diastolic pressure (peak velocity of early transmitral flow/peak velocity of early diastolic mitral annular motion ratio [E/E' ]) and estimated glomerular filtration rate (eGFR) in patients with type 2 diabetes mellitus, mild-to-moderate renal function impairment and LV relaxation impairment (E'≤7.1 cm/s).

METHODS

Plasma adrenomedullin concentration, E/E' and eGFR were assessed in 82 patients with type 2 diabetes.

RESULTS

Plasma adrenomedullin concentration was positively correlated with eGFR in patients with or without LV relaxation impairment, and inversely correlated with E/E' in patients with LV relaxation impairment. Multivariate linear regression analysis supported a role for plasma adrenomedullin in the association between E/E' and eGFR.

CONCLUSION

These results support the hypothesis that adrenomedullin modulates the interaction between the heart and kidneys in early subclinical cardiorenal syndrome in patients with type 2 diabetes mellitus.

Association of N-terminal pro-B-type natriuretic peptide with left ventricular structure and function in chronic kidney disease (from the Chronic Renal Insufficiency Cohort [CRIC])

We evaluated the cross-sectional associations of N-terminal pro-B-type natriuretic peptide (NT-proBNP) with cardiac structural and functional abnormalities in a cohort of patients with chronic kidney disease without clinical heart failure, the Chronic Renal Insufficiency Cohort (n = 3,232). The associations of NT-proBNP with echocardiographically determined left ventricular (LV) mass and LV systolic and diastolic function were evaluated using multivariate logistic and linear regression models. Reclassification of participants' predicted risk of LV hypertrophy (LVH), systolic and diastolic dysfunction was performed using a category-free net reclassification improvement index that compared a clinical model with and without NT-proBNP. The median NT-proBNP was 126.6 pg/ml (interquartile range 55.5 to 303.7). The greatest quartile of NT-proBNP was associated with a nearly threefold odds of LVH (odds ratio 2.7, 95% confidence interval [CI] 1.8 to 4.0) and LV systolic dysfunction (odds ratio 2.7, 95% CI 1.7 to 4.5) and a twofold odds of diastolic dysfunction (odds ratio 2.0, 95% CI 1.3 to 2.9) in the fully adjusted models. When evaluated alone as a screening test, NT-proBNP functioned modestly for the detection of LVH (area under the curve 0.66) and LV systolic dysfunction (area under the curve 0.62) and poorly for the detection of diastolic dysfunction (area under the curve 0.51). However, when added to the clinical model, NT-proBNP significantly reclassified participants' likelihood of having LVH (net reclassification improvement 0.14, 95% CI 0.13-0.15; p <0.001) and LV systolic dysfunction (net reclassification improvement 0.28, 95% CI 0.27 to 0.30; p <0.001) but not diastolic dysfunction (net reclassification improvement 0.10, 95% CI 0.10 to 0.11; p = 0.07). In conclusion, in this large chronic kidney disease cohort without heart failure, NT-proBNP had strong associations with prevalent LVH and LV systolic dysfunction.

Association of E/E' and NT-proBNP with renal function in patients with essential hypertension

Objectives

To evaluate the association of left ventricular (LV) diastolic function and N-terminal pro-brain natriuretic peptide (NT-proBNP) with renal function in essential hypertension.

Methods

LV diastolic function was estimated by the ratio of early diastolic velocities (E) from transmitral inflow to early diastolic velocities (E′) of tissue Doppler at mitral annulus (septal corner); NT-proBNP was measured in 207 hypertensive patients (mean age 56±14 years). The subjects were classified into 3 groups: E/E′≤10 group (n = 48), 10<E/E′≤15 group (n = 109) and E/E′>15 group (n = 50). The renal function was estimated by glomerular filtration rate (GFR) with ^99mTc-DTPA. GFR from 30 to 59 ml/min/1.73 m² was defined as Stage 3 chronic kidney disease (CKD). GFR was also estimated using the modified MDRD equation. Albuminuria was defined by urinary albumin/creatinine ratio (UACR).

Results

GFR was lower and UACR was higher in E/E′ >15 group than in 10< E/E′ ≤15 group or E/E′ ≤10 group (p<0.0001), GFR was significantly negative and UACR was positive correlated with E/E′ and NT-proBNP (p<0.0001). In multivariate stepwise linear analysis, GFR had significant correlation with age (p = 0.001), gender (p = 0.003), E/E′ (p = 0.03), lgNT-proBNP (p = 0.001) and lgUACR (p = 0.01), while eGFR had no significant correlation with E/E′ or lgNT-proBNP. Multivariate logistic regression analysis, adjusted for potential confounding factors, showed that participants in E/E′>15 group were more likely to have Stage 3 CKD compared with those in E/E′≤10 group with an adjusted odds ratio of 8.31 (p = 0.0036).

Conclusions

LV diastolic function, assessed with E/E′ and NT-proBNP is associated with renal function in essential hypertension.

Association of cardiac troponin T with left ventricular structure and function in CKD

BACKGROUND

Serum cardiac troponin T (cTnT) is associated with increased risk of heart failure and cardiovascular death in several population settings. We evaluated associations of cTnT levels with cardiac structural and functional abnormalities in a cohort of patients with chronic kidney disease (CKD) without heart failure.

STUDY DESIGN

Cross-sectional.

SETTING & PARTICIPANTS

Chronic Renal Insufficiency Cohort (CRIC; N=3,243).

PREDICTOR

The primary predictor was cTnT level. Secondary predictors included demographic and clinical characteristics, hemoglobin level, high-sensitivity C-reactive protein level, and estimated glomerular filtration rate using cystatin C.

OUTCOMES

Echocardiography was used to determine left ventricular (LV) mass and LV systolic and diastolic function.

MEASUREMENTS

Circulating cTnT was measured in stored sera using the highly sensitive assay. Logistic and linear regression models were used to examine associations of cTnT level with each echocardiographic outcome.

RESULTS

cTnT was detectable in 2,735 (84%) persons; median level was 13.3 (IQR, 7.7-23.8) pg/mL. Compared with undetectable cTnT (<3.0 pg/mL), the highest quartile (23.9-738.7 pg/mL) was approximately 2 times as likely to have LV hypertrophy (OR, 2.43; 95% CI, 1.44-4.09) in the fully adjusted model. cTnT level had a more modest association with LV systolic dysfunction; as a log-linear variable, a significant association was present in the fully adjusted model (OR of 1.4 [95% CI, 1.2-1.7] per 1-log unit; P < 0.001). There was no significant independent association between cTnT level and LV diastolic dysfunction. When evaluated as a screening test, cTnT level functioned only modestly for LV hypertrophy and concentric hypertrophy detection (area under the curve, 0.64 for both), with weaker areas under the curve for the other outcomes.

LIMITATIONS

The presence of coronary artery disease was not formally assessed using either noninvasive or angiographic techniques in this study.

CONCLUSIONS

In this large CKD cohort without heart failure, detectable cTnT had a strong association with LV hypertrophy, a more modest association with LV systolic dysfunction, and no association with diastolic dysfunction. These findings indicate that circulating cTnT levels in patients with CKD are predominantly an indicator of pathologic LV hypertrophy.

Associations between kidney function and subclinical cardiac abnormalities in CKD

Heart failure is a common consequence of CKD, and it portends high risk for mortality. However, among patients without known heart failure, the associations of different stages of estimated GFR (eGFR) with changes in cardiac structure and function are not well described. Here, we performed a cross-sectional analysis to study these associations among 3487 participants of the Chronic Renal Insufficiency Cohort Study. We estimated GFR using cystatin C. The prevalence of left ventricular hypertrophy (LVH) assessed by echocardiography was 32%, 48%, 57%, and 75% for eGFR categories ≥60, 45-59, 30-44, and <30 ml/min per 1.73 m(2), respectively. In fully adjusted multivariable analyses, subjects with eGFR levels of <30 ml/min per 1.73 m(2) had twofold higher odds of LVH (OR=2.20, 95% CI=1.40-3.40; P<0.001) relative to subjects with eGFR≥60 ml/min per 1.73 m(2). This reduction in kidney function also significantly associated with abnormal LV geometry but not diastolic or systolic dysfunction. An eGFR of 30-44 ml/min per 1.73 m(2) also significantly associated with LVH and abnormal LV geometry compared with eGFR≥60 ml/min per 1.73 m(2). In summary, in this large CKD cohort, reduced kidney function associated with abnormal cardiac structure. We did not detect significant associations between kidney function and systolic or diastolic function after adjusting for potential confounding variables.

The association between left ventricular diastolic function and a mild-to-moderate decrease in glomerular filtration rate in patients with type 2 diabetes mellitus

This prospective study evaluated the relationship between echocardiography parameters of left ventricular (LV) diastolic function and mild-to-moderate renal function impairment in 82 patients with type 2 diabetes mellitus. The mean age of the patients was 61.1 years. A significant correlation was found between estimated glomerular filtration rate (eGFR) and the ratio of peak velocity of early transmitral flow (E) to peak velocity of early diastolic mitral annular motion (E'). Cluster analysis revealed two subgroups of patients with different E' values but comparable eGFRs. The correlation between eGFR and E/E' was significant in 38 patients with E' ≤ 7.1 cm/s, but not significant in 44 patients with E' > 7.1 cm/s. The results suggest that the deterioration of LV relaxation (E') represents the underlying condition for the association between mild-to-moderate renal function impairment and the non-invasive parameter of LV end-diastolic pressure (E/E'), in patients with type 2 diabetes without any previous cardiovascular event and with well-controlled blood pressure.

Atherosclerosis in CKD: differences from the general population

The prevalence of cardiovascular morbidity and mortality is higher in patients with chronic kidney disease (CKD)-especially those with end-stage renal disease-than in the general population. The contribution of atherosclerosis to cardiovascular disease in patients with CKD remains unclear. Researchers in the 1970s proposed that atherosclerosis was the main cause of cardiovascular disease in patients with CKD and that its progression, based on observations of patients on long-term dialysis, was accelerated by the uremic state. Subsequent reports, however, favor the involvement of other mechanisms, such as arteriosclerosis (characterized by vascular stiffening), vascular calcification, 'myocyte/capillary mismatch', congestive cardiomyopathy, and sudden cardiac death. Imaging and morphological studies have contributed to our understanding of the pathogenesis and progression of cardiovascular disease associated with CKD. Based on clinical and experimental findings, we hypothesize the following: the initial cardiovascular abnormalities in the CKD setting include arteriosclerosis, left ventricular diastolic dysfunction, and left ventricular hypertrophy, abnormalities which, in adult patients, are often accompanied by atherosclerosis. The prevalence of atherosclerosis increases with age and is aggravated, but not specifically induced, by CKD. The cardiovascular events associated with atherosclerosis are more often fatal in patients with CKD than in individuals without CKD.