Evidence of left ventricular systolic and diastolic dysfunction by color tissue Doppler imaging despite normal ejection fraction in patients on chronic hemodialysis program

Comparison of left atrial deformation parameters between renal transplant and hemodialysis patients

Background

Renal transplantation (RT) has been demonstrated to improve left ventricular systolic function. However, only few studies have attempted to reveal the effects of transplantation on left atrial (LA) function. In our study, we aimed to compare LA function between RT and hemodialysis patients.

Methods

This cross-sectional study included 75 consecutive patients with RT, and 75 age- and gender-matched patients on maintenance hemodialysis. LA strain and strain rate (SR) analyzed by two-dimensional (2D) speckle tracking echocardiography (STE) were compared between the groups in addition to standard echocardiographic parameters.

Results

LA strain during reservoir phase (29.88 ± 5.76% vs 26.11 ± 5.74%, P < .001), LA strain during conduit phase (− 15.28 ± 5.00% vs − 12.92 ± 4.38%, P = .003), and LA strain during contraction phase (− 14.60 ± 3.32% vs − 13.19 ± 3.95%, P = .020) were higher in the transplantation group. Similarly, LA peak SR during reservoir phase (1.54 ± 0.33 s^− 1 vs 1.32 ± 0.33 s^− 1, P < .001), LA peak SR during conduit phase (− 1.47 ± 0.49 s^− 1 vs − 1.12 ± 0.42 s^− 1, P < .001), and LA peak SR during contraction phase (− 2.13 ± 0.46 s^− 1 vs − 1.83 ± 0.58 s^− 1, P = .001) were higher in the transplantation group as well.

Conclusions

LA function assessed by 2D STE was better in RT patients than hemodialysis patients. This may suggest favorable effects of RT on LA function.

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.

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.

Coronary artery calcification in CKD-5D patients is tied to adverse cardiac function and increased mortality

Background: Coronary artery calcification (CAC) is common in patients with chronic kidney disease on hemodialysis (CKD-5D) and is an important predictor of mortality. However, cardiac functional links between CAC and mortality have not been well established. This study tested the hypothesis that CAC increases mortality by adversely affecting cardiac function. Methods: Patients were recruited from 37 regional dialysis centers. 2-D and Doppler echocardiographic analyses were performed, and CAC was measured using 64-slice computed tomography. Relationships between CAC and echocardiographic measures of left ventricular (LV) function were analyzed. Survival was assessed with median follow-up of 37 months. Results: There were 157 patients: 59% male, 46% Caucasian, 48% diabetic. Median age was 55 years, and median duration of CKD-5D was 45 months. Agatston CAC scores > 100 were found in 69% of patients, with 51% having a score > 400. CAC was associated with measures of LV systolic and diastolic function (global longitudinal strain (GLS; rho = 0.270, p = 0.004)), peak LV systolic velocity (rho = –0.259, p = 0.004), and estimate of LV filling pressure (E:E’; rho = 0.286, p = 0.001). Multivariate regression confirmed these relationships after adjustment for age, gender, LV ejection fraction, and coronary artery disease. Valvular calcification varied linearly with CAC (p < 0.05). Both LV diastolic and systolic functional measures were significant predictors of mortality, the strongest of which was LV diastolic dysfunction. Conclusions: These findings show a link between CAC, cardiac function, and mortality in CKD-5D. LV diastolic function (E:E’), peak LV systolic velocity, and GLS are independent predictors of mortality. Valvular calcification may be an important marker of CAC in CKD-5D. These effects on cardiac function likely explain the high mortality with CKD-5D and describe a potentially-valuable role for echocardiography in the routine management of these patients.

Tissue Doppler Imaging and Intima-Media Thickness as Noninvasive Methods of Cardiovascular Risk Stratification in Patients After Kidney Transplantation

BACKGROUND

Cardiovascular complications, including coronary artery disease and chronic heart failure, are the leading causes of death in patients with chronic kidney disease. New echocardiographic techniques, such as tissue Doppler imaging (TDI) with strain and strain rate, are noninvasive, easy-to-perform methods of the estimation of left ventricular (LV) systolic and diastolic function. The aim of the study was to analyze the utility of new noninvasive methods of cardiovascular risk stratification in patients after kidney transplantation.

METHODS

We included 43 consecutive kidney transplant (KT) recipients, with 30 healthy subjects constituting the control group in the study. We evaluated LV morphology and LV systolic and diastolic function by means of echocardiography with TDI and intima-media thickness by ultrasonography of the carotid arteries.

RESULTS

LV mass index was significantly higher in transplanted patients, and both mitral inflow E/A and Em/Am ratios from pulsed myocardial imaging were significantly lower in the KT group as compared with the control group. The systolic wave of TDI at the basal segments was much lower in KT patients than in the control patients (P < .05). The mean value of strain rate was reduced in KT recipients as compared with the control patients. IMT was significantly higher in KT recipients.

CONCLUSIONS

Echocardiography with TDI provided more accurate information about systolic and diastolic LV function. KT recipients showed significant alterations in LV longitudinal myocardial function parameters estimated by strain and strain rate. Strain and strain rate are noninvasive methods, easy to repeat, and valuable for detecting myocardial LV dysfunction in asymptomatic KT recipients.

Cardiac imaging in patients with chronic kidney disease

Patients with chronic kidney disease (CKD) carry a high cardiovascular risk. In this patient group, cardiac structure and function are frequently abnormal and 74% of patients with CKD stage 5 have left ventricular hypertrophy (LVH) at the initiation of renal replacement therapy. Cardiac changes, such as LVH and impaired left ventricular systolic function, have been associated with an unfavourable prognosis. Despite the prevalence of underlying cardiac abnormalities, symptoms may not manifest in many patients. Fortunately, a range of available and emerging cardiac imaging tools may assist with diagnosing and stratifying the risk and severity of heart disease in patients with CKD. Moreover, many of these techniques provide a better understanding of the pathophysiology of cardiac abnormalities in patients with renal disease. Knowledge of the currently available cardiac imaging modalities might help nephrologists to choose the most appropriate investigative tool based on individual patient circumstances. This Review describes established and emerging cardiac imaging modalities in this context, and compares their use in CKD patients with their use in the general population.

Cardiac remodelling and functional alterations in mild-to-moderate renal dysfunction: comparison with healthy subjects

Introduction

Left ventricular (LV) hypertrophy (LVH) and reduced LV function correlate with poor prognosis in patients with chronic kidney disease (CKD). Our aim is to investigate whether mild-to-moderate CKD is associated with cardiac abnormalities.

Methods

Echocardiography, including tissue Doppler imaging, was performed in 103 patients with CKD at stages 2–3 and 4–5, and in 53 healthy controls. The systolic (s′) and diastolic myocardial velocity (e′), and the transmitral diastolic flow velocity (E) were measured, and E/e′ was calculated.

Results

Patients with chronic kidney disease had higher mean E/e′ than controls (mean E/e′: controls 5·00 ± 1·23 versus CKD 4–5 6·36 ± 1·71, P<0·001 and versus CKD 2–3 5·69 ± 1·47, P = 0·05), indicating altered diastolic function in the patients. The CKD groups showed lower longitudinal systolic function than controls, as assessed by atrio-ventricular plane displacement and s′ (mean s′: controls 11·5 ± 1·9 cm s⁻¹ versus CKD 4–5 10·4 ± 2·1 cm s⁻¹, P = 0·03 and versus CKD 2–3 10·4 ± 2·1 cm s⁻¹, P = 0·02). The prevalence of LVH was higher in patients with CKD than in controls (controls 13% versus CKD 4–5 37%, P = 0·006 and versus CKD 2–3 30%, P = 0·03).

Conclusion

Alterations in systolic and diastolic myocardial function can be seen in mild-to-moderate CKD compared with controls, indicating that cardiac involvement starts early in CKD, which may be a precursor of premature cardiac morbidity.

Echocardiography in hemodialysis patients: uses and challenges

Patients with end-stage renal disease undergoing hemodialysis have high rates of morbidity and mortality. Cardiovascular disease accounts for almost half of this mortality, with the single most common cause being sudden cardiac death. Early detection of abnormalities in cardiac structure and function may be important to allow timely and appropriate cardiac interventions. Echocardiography is noninvasive cardiac imaging that is widely available and provides invaluable information on cardiac morphology and function. However, it has limitations. Echocardiography is operator dependent, and image quality can vary depending on the operator's experience and the patient's acoustic window. Hemodialysis patients undergo regular hemodynamic changes that also may affect echocardiographic findings. An understanding of the prognostic significance and interpretation of echocardiographic results in this setting is important for patient care. There are some emerging techniques in echocardiographic imaging that can provide more detailed and accurate information compared with conventional 2-dimensional echocardiography. Use of these novel tools may further our understanding of the pathophysiology of cardiac disease in patients with end-stage renal disease undergoing hemodialysis.

Speckle tracking echocardiography detects uremic cardiomyopathy early and predicts cardiovascular mortality in ESRD

Cardiovascular mortality is high in ESRD, partly driven by sudden cardiac death and recurrent heart failure due to uremic cardiomyopathy. We investigated whether speckle-tracking echocardiography is superior to routine echocardiography in early detection of uremic cardiomyopathy in animal models and whether it predicts cardiovascular mortality in patients undergoing dialysis. Using speckle-tracking echocardiography in two rat models of uremic cardiomyopathy soon (4-6 weeks) after induction of kidney disease, we observed that global radial and circumferential strain parameters decreased significantly in both models compared with controls, whereas standard echocardiographic readouts, including fractional shortening and cardiac output, remained unchanged. Furthermore, strain parameters showed better correlations with histologic hallmarks of uremic cardiomyopathy. We then assessed echocardiographic and clinical characteristics in 171 dialysis patients. During the 2.5-year follow-up period, ejection fraction and various strain parameters were significant risk factors for cardiovascular mortality (primary end point) in a multivariate Cox model (ejection fraction hazard ratio [HR], 0.97 [95% confidence interval (95% CI), 0.95 to 0.99; P=0.012]; peak global longitudinal strain HR, 1.17 [95% CI, 1.07 to 1.28; P<0.001]; peak systolic and late diastolic longitudinal strain rates HRs, 4.7 [95% CI, 1.23 to 17.64; P=0.023] and 0.25 [95% CI, 0.08 to 0.79; P=0.02], respectively). Multivariate Cox regression analysis revealed circumferential early diastolic strain rate, among others, as an independent risk factor for all-cause mortality (secondary end point; HR, 0.43; 95% CI, 0.25 to 0.74; P=0.002). Together, these data support speckle tracking as a postprocessing echocardiographic technique to detect uremic cardiomyopathy and predict cardiovascular mortality in ESRD.

Assessment of left ventricular hemodynamics and function of patients with uremia by vortex formation using vector flow mapping

A novel echocardiographic method, vector flow mapping (VFM), acquires velocity vector from color Doppler velocity data. The purpose of this study was to evaluate whether VFM could provide useful information on intracardiac flow and helpful to evaluate left ventricular (LV) function. Thirty-eight patients with uremia undergoing hemodialysis and 30 healthy volunteers were enrolled. The maximum vector velocity, maximum diameter and duration of the intracardiac vortex were measured using VFM software during systole and diastole. The maximum vector velocity of the vortex and the peak velocities at the basal septum and lateral mitral annulus measured by tissue Doppler imaging (TDI) were correlated. The maximum diameter and duration of vortex formation were significantly higher in uremic patients compared with the control group during the ejection phase (40.6 ± 7.9 cm/sec vs. 28.1 ± 3.9 cm/sec; 297.1 ± 22.1 msec vs. 145.4 ± 19.3 msec, all P < 0.001). The maximal diameters of the vortex were higher in uremic patients compared with the control group during diastole (25.6 ± 3.4 mm vs. 16.4 ± 2.1 mm; 34.3 ± 3.1 mm vs. 26.8 ± 3.9 mm; 37.5 ± 2.4 mm vs. 20.9 ± 2.1 mm; all P < 0.001). The maximum vector velocities were lower in mid-diastole and late diastole (23.6 ± 2.3 cm/sec vs. 45.2 ± 3.7 cm/sec; 31.9 ± 2.9 cm/sec vs. 54.7 ± 3.2 cm/sec, all P < 0.001). There was a correlation between the maximum vector velocity of the vortex in mid-diastole and E'/A' at the septum and lateral mitral annulus (r = 0.70, r = 0.76, P < 0.001). Vortex can be utilized to provide intracardiac dynamic information using VFM and it may be a good supplement for evaluating LV function.

Hemodialysis does not impair ventricular functions over 2 years

We aimed to evaluate the long-term effect of hemodialysis (HD) treatment on left and right ventricular (LV and RV) functions in patients with end-stage renal disease. The study population consisted of 22 patients with newly diagnosed end-stage renal disease. Before an arteriovenous fistula was surgically created for HD, the patients were evaluated by echocardiography for systolic and diastolic functions. After the first HD session (mean 24.22 ± 2.14 months), the second echocardiographic evaluations were performed. Left ventricular and RV functions before and after long-term HD treatment were compared. The mean age was 55 ± 13 years and 10 (45%) of the patients were female. After long-term HD treatment, the isovolumic relaxation time was significantly decreased; however, the peak early (E) and late (A) diastolic mitral inflow velocities, E/A ratio, and deceleration time of E wave were not significantly different from the baseline measurements. Also, there was no significantly change in the early diastolic velocity (Ea) of the lateral mitral anulus and the E/Ea ratio. Pulmonary vein peak diastolic velocity, peak atrial reversal velocity, and peak atrial reversal velocity duration remained almost unchanged even though the pulmonary vein peak systolic velocity and the pulmonary vein peak systolic velocity/pulmonary vein peak diastolic velocity ratio were significantly lower after long-term HD treatment. In addition, LV systolic functions, LV diameters, LV mass index, left atrium size, and RV diastolic functions were not statistically different after long-term HD treatment. The myocardium is exposed to hemodynamic, metabolic, and neuro-humoral abnormalities during HD treatment; however, the long-term effects of HD on ventricular functions are not clearly known. The present study showed that the long-term effects of HD on LV and RV functions were insignificant in patients with end-stage renal disease. We have demonstrated that the LV and RV functions did not change significantly after long-term HD treatment. We suggest that this result may be due to regulated blood pressure levels of the patients, treatment of anemia and other metabolic disorders during the HD period and the prevention of weight gain and hypervolemia.

Effect of maintenance hemodialysis on diastolic left ventricular function in end-stage renal disease

PURPOSE

To analyze the effect of maintenance hemodialysis on left ventricular diastolic function in patients with end-stage renal disease.

METHODS

Study population consisted of 42 patients with end-stage renal disease. Before an arteriovenous fistula was surgically created, the patients were evaluated by conventional and Doppler echocardiography and Doppler tissue imaging. Then, the patients undergoing hemodialysis treatment when the arteriovenous fistula was compleated. After the first hemodialysis session (mean 76.14 ± 11.37 days) the second echocardiographic evaluations were performed.

RESULTS

Mean age was 58 ± 13 years and 21 (%50) of the patients were female. After maintenance hemodialysis treatment; peak early (E) and peak late (A) diastolic mitral inflow velocities and E/A ratio were not significantly change however the deceleration time of E wave and left atrial diameter were significantly increased. Also there was no change in the early (Em) and late (Am) diastolic myocardial velocities and Em/Am ratios of lateral and septal walls of left ventricular. E/Em ratio was decreased insignificantly. Pulmonary vein velocities and right ventricular functions are remained almost unchanged after hemodialysis treatment.

DISCUSSION

The acute and long-term effect of hemodialysis on left ventricular diastolic function is unclearly. Patients with end-stage renal disease treatment with hemodialysis via arteriovenous fistula experience a variety of hemodynamic and metabolic abnormalities that predispose to alterations in left and right ventricular functions. The present study showed that left ventricular diastolic function except left atrial diameter and right ventricular functions were not significantly change, however left ventricular systolic functions were impaired after maintenance hemodialysis treatment in patients with end-stage renal disease.

CONCLUSION

It has been suggested that echocardiographic parameters are useful markers for evaluation of left ventricular and right ventricular functions in patients with end-stage renal disease. However, in patients with endstage renal disease treated with hemodialysis, repeated assessment of echocardiographic examinations to observe serial changes in left and right ventricular functions are not yet well established. In this study, we showed that acute changes of volume status and electrolytes and autonomic regulation by hemodialysis session did not affect left ventricular diastolic and right ventricular functions in a relatively long term.

Cardiac assessment in chronic kidney disease

Patients with chronic kidney disease are well recognized to develop a wide range of cardiac structural and functional abnormalities. These changes may be progressive and relate directly to a grossly aggravated risk of cardiovascular events and reduced survival. Although conventional methods of cardiac assessment have been shown to be useful, they are limited by insufficient sensitivity and specificity, to fully appreciate the overall degree of myocardial distress that is common in these patients. This article aims to review the use of established and emerging cardiac imaging tools and, in particular, their application in patients with chronic kidney disease.

The impact of kidney transplantation on heart failure risk varies with candidate body mass index

BACKGROUND

The relationship of body mass index (BMI) with heart failure (HF) risk before and after kidney transplant is not well described.

METHODS

We examined United States Renal Data System records for 67,591 kidney transplant candidates (1995-2004) with Medicare insurance and BMI data at listing. Heart failure diagnoses were ascertained from Medicare billing claims. Body mass index was categorized per World Health Organization criteria. We modeled time-dependent associations (adjusted hazard ratio, aHR) of transplant with HF risk after listing compared with waiting in each BMI group by multivariable, stratified Cox regression. The time-dependent exposure variables partitioned relative risk of HF after transplant versus waiting into early (90 days) posttransplant periods.

RESULTS

The BMI distribution of listed candidates was as follows: 3.7% under, 40.4% normal, 32.0% over, 16.2% obese, and 7.7% morbidly obese weight. The prevalence of HF among patients awaiting transplant reached 57.4% by 3 years. Deceased-donor transplant was associated with increased early HF risk compared with continued waiting-aHRs ranged from 2.23 for normal-BMI to 2.82 for morbidly obese patients. However, transplant reduced the risk of HF in the late posttransplant period from 54% (aHR 0.46) in normal-BMI to 32% (aHR 0.68) for morbidly obese patients. Relative benefits were largest for normal-weight candidates who received live-donor transplants (aHR 0.31).

CONCLUSIONS

Heart failure risk improves in obese patients in the long term after kidney transplant, but not as much as for nonobese patients. There is need for close monitoring and for new strategies to reduce HF risk in obese patients before and after transplant.

Does oxidative stress modulate left ventricular diastolic function in asymptomatic subjects with hereditary hemochromatosis?

BACKGROUND

Little is known about the early mechanisms mediating left ventricular (LV) diastolic dysfunction in patients with hereditary hemochromatosis (HH). However, the increased oxidative stress related to iron overload may be involved in this process, and strain rate (SR), a sensitive echocardiography-derived measure of diastolic function, may detect such changes.

AIM

we evaluated the relationship between left ventricular diastolic function measured with tissue Doppler SR and oxidative stress in asymptomatic HH subjects and control normal subjects.

MATERIALS AND METHODS

Ninety-four consecutive visits of 43 HH subjects, age 30-74 (50 +/- 10, mean +/- SD), and 37 consecutive visits of 21 normal volunteers, age 30-63 (48 +/- 8), were evaluated over a 3-year period. SR was obtained from the basal septum in apical four-chamber views. All patients had confirmed C282Y homozygosity, a documented history of iron overload, and were New York Heart Association functional class I. Normal volunteers lacked HFE gene mutations causing HH.

RESULTS

In the HH subjects, the SR demonstrated moderate but significant correlations with biomarkers of oxidative stress; however, no correlations were noted in normal subjects. The biomarkers of iron overload per se did not show significant correlations with the SR.

CONCLUSION

Although our study was limited by the relatively small subject number, these results suggest that a possible role of oxidative stress to affect LV diastolic function in asymptomatic HH subjects and SR imaging may be a sensitive measure to detect that effect.

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

BACKGROUND

The disadvantageous effect of kidney dysfunction on left ventricular (LV) diastolic function is still unknown.

METHODS

Forty non-chronic kidney disease (CKD) patients and 202 CKD patients, aged 40-89, were examined by standard echocardiography and the new modality of tissue Doppler imaging. All subjects were divided into 5 groups depending on their estimated glomerular filtration rate (GFR: ml/min/BSA). Classifications by GFR were defined as follows: group 1 (more than 90: normal subjects), group 2 (60-89), group 3 (30-59), group 4 (15-29) and group 5 (less than 15).

RESULTS

There were no significant differences in LV systolic function among the groups. Mitral E velocity was significantly lower in groups 1-4 (p<0.01-0.02) compared with group 5. Mitral A velocity was higher in groups 2-5 (p<0.01-0.04) compared with group 1. The ratio of mitral E and A velocities (E/A) was significantly higher in group 1 (p<0.02-0.05) compared with groups 2-5. Deceleration time was significantly shorter in groups 1 and 2 (p<0.01-0.02) compared with groups 4 and 5. Furthermore, it was significantly lower in group 5 (p<0.01) compared with group 4. Early diastole velocity of mitral annulus (Ea) by tissue Doppler was also higher in group 1 (9.1+/-2.5; p<0.01-0.04) compared with group 2 (7.9+/-1.7), group 3 (7.9+/-1.6), group 4 (7.5+/-2.1), and group 5 (7.6+/-2.0). Severity of the kidney dysfunction appears to parallel with the rise of E/Ea significantly (p<0.02). A, E/A and Ea could differentiate between groups 1 and 2 with early stage of CKD.

CONCLUSIONS

These data suggest that LV diastolic dysfunction was observed even in patients with early stages of chronic kidney dysfunction. Doppler indices combined with conventional and tissue Doppler methods could detect the subtle changes of diastolic function due to kidney dysfunction.