Kidney transplantation in patients with ventricular ejection fraction less than 50 percent: features and posttransplant outcome

Impact of kidney transplant on post-operative morbidity and mortality in patients with pre-operative cardiac dysfunction

BACKGROUND

Several studies show an increase in complications, both cardiac and non-cardiac, and a higher mortality in patients with preexisting cardiac disease when they undergo elective surgery. Due to the high incidence of cardiac dysfunction in patients with concomitant chronic kidney disease, we wanted to determine if the same negative impact is demonstrated in patients undergoing kidney transplantation.

METHODS

A retrospective analysis was done on 582 patients who underwent kidney transplant from a single transplant center between 2014 and 2019. Participants for this study were divided into two groups based on cardiac ejection fraction: normal EF (≥40%) (n = 540) and low EF (<40%) (n = 33); exclusion criteria included patients undergoing multi-organ transplants (n = 9). Characteristics and outcomes of patients were compared before and after transplant using chi-square tests for categorical measures, and either Kruskal-Wallis or paired Student's t tests for continuous measures. Overall survival (OS) between groups was assessed using the Kaplan-Meier test. We compared outcomes between the normal EF and low EF groups using logistic regression in raw data, and propensity score matched sample and inverse-probability-weighting to mitigate selection bias.

RESULTS

There was no significant difference in survival between patients in the low EF and normal EF groups (p = .33). Among patients with low EF, mean EF after transplant significantly improved (mean: 55.83% ± 5.75%) compared to mean EF before transplant (38.28% ± 7.35%), (p = < .0001). Of the patients with a low EF before transplant, 1 in 5 had a history of CAD, compared to only 1 in 10 among those patients with a normal EF, p = .0657. Post-transplant complications were comparable between the groups.

CONCLUSION

Patients undergoing kidney transplantation with a low ejection fraction do not demonstrate an increased incidence of morbidity or mortality in the peri- and post-transplant follow-up compared with patients with a normal ejection fraction. Cardiac events post-transplantation is also comparable between the two groups. Of note, patients with a low EF have a significantly improved EF after kidney transplant which is likely a function of improvement in their physiologic state after the kidney transplant.

A Single-Center Experience With Kidney Transplantation in Patients Who Had Low Left Ventricular Ejection Fraction

OBJECTIVES

Left ventricular hypertrophy is one of the most typical cardiac abnormalities detected in patients with end-stage renal disease. In patients with congestive heart failure, the most crucial factor determining patient survival is left ventricular ejection fraction. Herein, we present our experience with living donor kidney transplant recipients with a left ventricular ejection fraction of <50%.

MATERIALS AND METHODS

Patients who underwent living donor kidney transplant in our center between November 2008 and November 2021 and had pretransplant left ventricular ejection fraction <50% were included. All patients had dialysis the day before surgery. All patients underwent 2-dimensional echocardiograms after dialysis and were categorized according to New York Heart Association classification, pretransplant and on posttransplant day 5. Demographic parameters and additional data, including pretransplant and posttransplant day 5 New York Heart Association classification, left ventricular ejection fraction at 6 months, and graft survival at 6 months, as well as patient survival data, were analyzed.

RESULTS

Our study included 31 patients (mean age of 46.6 ± 18.3; range, 11-77 years). We found significant differences in New York Heart Association classifications before and after transplant, indicating that kidney transplant had a positive effect on pretransplant congestive heart failure in patients with low left ventricular ejection fraction (P = .001). The mean pretransplant left ventricular ejection fraction was 32 ± 9.9% (range, 1%-45%), whereas the mean 6-month posttransplant left ventricular ejection fraction was 52 ± 8.7% (range, 28%-63%) (P < .001). Both graft loss and all-cause mortality rates were 12.9%.

CONCLUSIONS

Low left ventricular ejection fraction is not a contraindication for kidney transplant. We suggest that myocardial scintigraphy should be performed in patients with end-stage renal disease and low left ventricular ejection fraction, and kidney transplant should be considered in those without ischemic findings.

Comparison of left ventricular subclinical systolic dysfunction between hemodialysis patients and renal transplant recipients using real time three-dimensional echocardiography

AIMS

The relationship between chronic kidney disease and development of heart failure is a well-known clinical entity. Systolic dyssynchrony index (SDI_16) is a new diagnostic tool for detection of subclinical left ventricular (LV) systolic dysfunction by using three-dimensional echocardiography (3DE). We aimed to investigate this parameter in patients with end-stage renal disease who were receiving hemodialysis and patients with renal transplant compared to healthy control subjects.

MATERIAL AND METHODS

Forty-five hemodialysis patients, 45 patients with renal transplant and 45 age-sex matched healthy control subjects included in the study. All participants were evaluated with 3DE in the interdialytic phase for measurement of LV volumes, ejection fraction and SDI_16 parameter.

RESULTS

Both LV diastolic and systolic volumes were significantly higher in hemodialysis group compared to renal transplant group and healthy controls, but this finding did not translate to a statistically significant difference for LVEF measurements between groups (58.71 ± 3.53 vs. 57.17 ± 2.97 vs. 59.23 ± 3.26, p = .16 for renal transplant and hemodialysis and healthy control groups, respectively). Mean value of SDI_16 parameters was significantly higher in hemodialysis group compared to renal transplant group (7.93 ± 2.50 vs. 3.72 ± 1.71, p < .001) and healthy controls (7.93 ± 2.50 vs. 3.00 ± .99, p < .001); whereas, it was similar between renal transplant group and control subjects (3.72 ± 1.71 vs. 3.00 ± .99, p = .10).

CONCLUSION

SDI_16 was significantly higher in hemodialysis patients compared to patients with renal transplant and healthy controls.

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.

Comparison of Outcomes in Patients Undergoing Renal Transplantation With Impaired vs Normal Left Ventricular Ejection Fraction

BACKGROUND

Renal transplantation improves long-term outcomes in patients with end-stage renal disease (ESRD); however, patients with impaired left ventricular ejection fraction (LVEF) are less likely to be selected for renal transplantation. We sought to evaluate the effect of renal transplantation in this population.

METHODS

We retrospectively evaluated 181 patients who underwent renal transplantation between 2011 and 2016. For patients with pretransplant LVEF <50% (cohort 1) and ≥50% (cohort 2), we evaluated the effect of renal transplantation on LVEF, graft failure, and mortality.

RESULTS

Cohort 1 comprised 24 patients (mean age, 47 years; pretransplant LVEF 38%). Cohort 2 comprised 157 patients (mean age, 53 years; pretransplant LVEF 64%). Forty-six percent of cohort 1 experienced significant improvement in LVEF posttransplant, with mean LVEF improvement from 38% to 66%. There was no significant association between pretransplant LVEF and graft failure (hazard ratio [HR] = 2.7; 95% confidence interval [CI], 0.6-11.4; P = .1) or mortality (HR = 1.02; 95% CI, 0.3-3.6; P = .9). Coronary artery disease predicted mortality (HR = 3.12; 95% CI, 1.2-8.4; P = .02). Older age trended toward higher mortality (HR = 1.04; 95% CI, 1.0-1.1; P = .05). Younger age predicted graft failure (HR = 0.96; 95% CI, 0.8-0.9; P = .02).

CONCLUSIONS

In patients with ESRD undergoing renal transplantation, there was no significant association between pretransplant LVEF and mortality or graft failure, suggesting that patients with ESRD with impaired LVEF can experience positive posttransplant outcomes.

Cardiovascular mortality in liver and kidney transplant recipients: A retrospective analysis from a single institution

Previous studies have demonstrated cardiovascular causes to be among the leading causes of death after liver (LT) and kidney transplantation (KT). Although both recipient populations have unique pre-transplant cardiovascular burdens, they share similarities in post-transplant exposure to cardiovascular risk factors. The aim of this study was to compare cardiovascular mortality after LT and KT.We analyzed causes of death in 370 consecutive LT and 207 KT recipients from in-hospital records at a single tertiary transplant center. Cardiovascular causes of death were defined as cardiac arrest, heart failure, pulmonary embolism, or myocardial infarction.After a median follow-up of 36.5 months, infection was the most common cause of death in both cohorts, followed by cardiovascular causes in KT recipients and graft-related causes in LT recipients in whom cardiovascular causes were the third most common. Cumulative incidence curves for cardiovascular mortality computed with death from other causes as the competing risk were not significantly different (P = .36). While 1-year cumulative cardiovascular mortality was similar (1.6% after LT and 1.5% after KT), the estimated 4-year probability was higher post-KT (3.8% vs. 1.6%). Significant pre-transplant risk factors for overall mortality after KT in multivariable analysis were age at transplantation, left ventricular ejection fraction <50%, and diastolic dysfunction grade 2 or greater, while significant risk factors for cardiovascular mortality were peripheral artery disease and left ventricular ejection fraction <50%. In the LT group no variables remained significant in a multivariable model for either overall or cardiovascular mortality.The present study found no significant overall difference in cardiovascular mortality after LT and KT. While LT and KT recipients may have similar early cardiovascular mortality, long-term risk is potentially lower after LT. Differing characteristics of cardiovascular death between these two patient populations should be further investigated.

Cardiovascular Functional Reserve Before and After Kidney Transplant

Importance

Restitution of kidney function by transplant confers a survival benefit in patients with end-stage renal disease. Investigations of mechanisms involved in improved cardiovascular survival have relied heavily on static measures from echocardiography or cardiac magnetic resonance imaging and have provided conflicting results to date.

Objectives

To evaluate cardiovascular functional reserve in patients with end-stage renal disease before and after kidney transplant and to assess functional and morphologic alterations of structural-functional dynamics in this population.

Design, Setting, and Participants

This prospective, nonrandomized, single-center, 3-arm, controlled cohort study, the Cardiopulmonary Exercise Testing in Renal Failure and After Kidney Transplantation (CAPER) study, included patients with stage 5 chronic kidney disease (CKD) who underwent kidney transplant (KTR group), patients with stage 5 CKD who were wait-listed and had not undergone transplant (NTWC group), and patients with hypertension only (HTC group) seen at a single center from April 1, 2010, to January 1, 2013. Patients were followed up longitudinally for up to 1 year after kidney transplant. Clinical data collection was completed February 2014. Data analysis was performed from June 1, 2014, to March 5, 2015. Further analysis on baseline and prospective data was performed from June 1, 2017, to July 31, 2019.

Main Outcomes and Measures

Cardiovascular functional reserve was objectively quantified using state-of-the-art cardiopulmonary exercise testing in parallel with transthoracic echocardiography.

Results

Of the 253 study participants (mean [SD] age, 48.5 [12.7] years; 141 [55.7%] male), 81 were in the KTR group, 85 in the NTWC group, and 87 in the HTC group. At baseline, mean (SD) maximum oxygen consumption (V̇O2max) was significantly lower in the CKD groups (KTR, 20.7 [5.8] mL · min-1 · kg-1; NTWC, 18.9 [4.7] mL · min-1 · kg-1) compared with the HTC group (24.9 [7.1] mL · min-1 · kg-1) (P < .001). Mean (SD) cardiac left ventricular mass index was higher in patients with CKD (KTR group, 104.9 [36.1] g/m2; NTWC group, 113.8 [37.7] g/m2) compared with the HTC group (87.8 [16.9] g/m2), (P < .001). Mean (SD) left ventricular ejection fraction was significantly lower in the patients with CKD (KTR group, 60.1% [8.6%]; NTWC group, 61.4% [8.9%]) compared with the HTC group (66.1% [5.9%]) (P < .001). Kidney transplant was associated with a significant improvement in V̇O2max in the KTR group at 12 months (22.5 [6.3] mL · min-1 · kg-1; P < .001), but the value did not reach the V̇O2max in the HTC group (26.0 [7.1] mL · min-1 · kg-1) at 12 months. V̇O2max decreased in the NTWC group at 12 months compared with baseline (17.7 [4.1] mL · min-1 · kg-1, P < .001). Compared with the KTR group (63.2% [6.8%], P = .02) or the NTWC group (59.3% [7.6%], P = .003) at baseline, transplant was significantly associated with improved left ventricular ejection fraction at 12 months but not with left ventricular mass index.

Conclusions and Relevance

The findings suggest that kidney transplant is associated with improved cardiovascular functional reserve after 1 year. In addition, cardiopulmonary exercise testing was sensitive enough to detect a decline in cardiovascular functional reserve in wait-listed patients with CKD. Improved V̇O2max may in part be independent from structural alterations of the heart and depend more on ultrastructural changes after reversal of uremia.

Cardiovascular Functional Changes in Chronic Kidney Disease: Integrative Physiology, Pathophysiology and Applications of Cardiopulmonary Exercise Testing

The development of cardiovascular disease during renal impairment involves striking multi-tiered, multi-dimensional complex alterations encompassing the entire oxygen transport system. Complex interactions between target organ systems involving alterations of the heart, vascular, musculoskeletal and respiratory systems occur in Chronic Kidney Disease (CKD) and collectively contribute to impairment of cardiovascular function. These systemic changes have challenged our diagnostic and therapeutic efforts, particularly given that imaging cardiac structure at rest, rather than ascertainment under the stress of exercise, may not accurately reflect the risk of premature death in CKD. The multi-systemic nature of cardiovascular disease in CKD patients provides strong rationale for an integrated approach to the assessment of cardiovascular alterations in this population. State-of-the-art cardiopulmonary exercise testing (CPET) is a powerful, dynamic technology that enables the global assessment of cardiovascular functional alterations and reflects the integrative exercise response and complex machinery that form the oxygen transport system. CPET provides a wealth of data from a single assessment with mechanistic, physiological and prognostic utility. It is an underutilized technology in the care of patients with kidney disease with the potential to help advance the field of cardio-nephrology. This article reviews the integrative physiology and pathophysiology of cardio-renal impairment, critical new insights derived from CPET technology, and contemporary evidence for potential applications of CPET technology in patients with kidney disease.

Successful Kidney Transplantation Alone With Severe Left Ventricular Systolic Dysfunction of Ejection Fraction 14%: A Case Report

It is well known that correction of uremia by kidney transplantation alone (KTA) improves left ventricular systolic dysfunction (LVSD). However, for kidney transplant candidates with extremely severe LVSD, KTA is considered to be contraindicated because of the high risk of peri-operative management. We report a case of successful kidney transplantation with severe LVSD with an ejection fraction (EF) of 14% and low systolic blood pressure (SBP) of approximately 65 to 80 mm Hg. In this case, in spite of an extremely low EF and SBP, functional capacity was assessed using metabolic equivalents (METs) and showed a level of almost 4. The operation was performed carefully, considering the cardiac, operative, and anesthetic risks. No surgical complications occurred, and the patient received intensive care during the peri-operative period. His postoperative course was almost favorable, and he was discharged on postoperative day 29. The present report concludes that evaluation of METs may expand the indication for KTA in patients with extremely severe LVSD.

Cardiovascular disease in the kidney transplant recipient: epidemiology, diagnosis and management strategies

Kidney transplantation (KT) is the optimal therapy for end-stage kidney disease (ESKD), resulting in significant improvement in survival as well as quality of life when compared with maintenance dialysis. The burden of cardiovascular disease (CVD) in ESKD is reduced after KT; however, it still remains the leading cause of premature patient and allograft loss, as well as a source of significant morbidity and healthcare costs. All major phenotypes of CVD including coronary artery disease, heart failure, valvular heart disease, arrhythmias and pulmonary hypertension are represented in the KT recipient population. Pre-existing risk factors for CVD in the KT recipient are amplified by superimposed cardio-metabolic derangements after transplantation such as the metabolic effects of immunosuppressive regimens, obesity, posttransplant diabetes, hypertension, dyslipidemia and allograft dysfunction. This review summarizes the major risk factors for CVD in KT recipients and describes the individual phenotypes of overt CVD in this population. It highlights gaps in the existing literature to emphasize the need for future studies in those areas and optimize cardiovascular outcomes after KT. Finally, it outlines the need for a joint 'cardio-nephrology' clinical care model to ensure continuity, multidisciplinary collaboration and implementation of best clinical practices toward reducing CVD after KT.

Cardiorenal Syndrome: Classification, Pathophysiology, Diagnosis, and Treatment Strategies: A Scientific Statement From the American Heart Association

Cardiorenal syndrome encompasses a spectrum of disorders involving both the heart and kidneys in which acute or chronic dysfunction in 1 organ may induce acute or chronic dysfunction in the other organ. It represents the confluence of heart-kidney interactions across several interfaces. These include the hemodynamic cross-talk between the failing heart and the response of the kidneys and vice versa, as well as alterations in neurohormonal markers and inflammatory molecular signatures characteristic of its clinical phenotypes. The mission of this scientific statement is to describe the epidemiology and pathogenesis of cardiorenal syndrome in the context of the continuously evolving nature of its clinicopathological description over the past decade. It also describes diagnostic and therapeutic strategies applicable to cardiorenal syndrome, summarizes cardiac-kidney interactions in special populations such as patients with diabetes mellitus and kidney transplant recipients, and emphasizes the role of palliative care in patients with cardiorenal syndrome. Finally, it outlines the need for a cardiorenal education track that will guide future cardiorenal trials and integrate the clinical and research needs of this important field in the future.

Kidney transplantation and cardiomyopathy: Concepts and controversies in clinical decision-making

Increasing comorbidities and an aging population have led to a tremendous increase in the burden of both kidney and cardiac dysfunction. Concomitant cardiomyopathy exposes the patients with kidney disease to further physiological, hemodynamic, and pathologic alterations. Kidney transplantation imposes lesser anesthetic and surgical complexities compared to another solid organ transplant. The surgical decision-making remains an unsettled issue in these conditions. The surgical choices, techniques, and sequences in kidney transplant and cardiac surgery depend on the pathophysiological perturbations and perioperative outcomes. The absence of randomized controlled trials eludes us from suggesting definite management protocol in patients with end-stage kidney disease with cardiomyopathy. Nevertheless, in this review, we extracted data from published literature to understand the pathophysiologic interactions between end-stage renal diseases with cardiomyopathy and also proposed the management algorithm in this challenging scenario. The proposed management algorithm would ensure consensus across all stakeholders involved in decision-making. Our simplistic evidence-based approach would augur future randomized trials and would further ensure refinement in our management approach after the emergence of more definitive evidence.

Cardiac risk assessment for end-stage renal disease patients on the renal transplant waiting list

Cardiovascular disease is a leading cause of morbidity and mortality and is becoming more prevalent as the population ages and risk factors increase. This is most apparent in the end-stage renal disease (ESRD) patient population. In part, this is due to cofactors such as diabetes and hypertension commonly predisposing to progressive renal disease, as well as being a direct consequence of having renal failure. Of all major organ failures, kidney failure is the most likely to be managed chronically using renal replacement therapy and, ultimately, transplant. However, lack of transplant organs and a large renal failure cohort means waiting lists are often quite long and may extend to 5-10 years. Due to the cardiac risk factors inherent in patients awaiting transplant, many succumb to cardiac issues while waiting and present an increased per-procedural cardiac risk that extends into the post-transplant period. We aim to review the epidemiology of coronary artery disease in this population and the etiology as it relates to ESRD and its associated co-factors. We also will review the current approaches, recommendations and evidence for management of these patients as it relates to transplant waiting lists before and after the surgery. Recommendations on how to best manage patients in this cohort revolve around the available evidence and are best customized to the institution and the structure of the program. It is not clear whether the revascularization of patients without symptoms and with a good functional status yields any improvement in outcomes. Therefore, each individual case should be considered based on the risk factors, symptoms and functional status, and approached as part of a multi-disciplinary assessment program.

Heart failure in chronic kidney disease: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

The incidence and prevalence of heart failure (HF) and chronic kidney disease (CKD) are increasing, and as such a better understanding of the interface between both conditions is imperative for developing optimal strategies for their detection, prevention, diagnosis, and management. To this end, Kidney Disease: Improving Global Outcomes (KDIGO) convened an international, multidisciplinary Controversies Conference titled Heart Failure in CKD. Breakout group discussions included (i) HF with preserved ejection fraction (HFpEF) and nondialysis CKD, (ii) HF with reduced ejection fraction (HFrEF) and nondialysis CKD, (iii) HFpEF and dialysis-dependent CKD, (iv) HFrEF and dialysis-dependent CKD, and (v) HF in kidney transplant patients. The questions that formed the basis of discussions are available on the KDIGO website http://kdigo.org/conferences/heart-failure-in-ckd/, and the deliberations from the conference are summarized here.

Myocardial remodeling after kidney transplantation: a case report

Background

Lupus nephritis (LN) is one of the most common manifestations of systemic lupus erythematosus (SLE) and is often the most serious organ complication and the cause of premature death of such a patient. Most of other organs and systems can be also affected. A typical complication is a cardiovascular involvement leading to the development of heart failure. According to current therapeutic standards, kidney transplantation is the treatment of choice in patients with renal failure in course of LN. On the contrary, a kidney transplantation in a patient with an additional heart disease poses a serious clinical challenge.

Case presentation

We present a case of a 49-year-old woman with renal and heart failure following a long-term SLE prepared for kidney transplantation. During the SLE course, the function of the heart and kidneys gradually deteriorated. The patient required the initiation of renal replacement therapy and was dialyzed until a kidney transplantation for 4 years. In the preparation of the patient for the surgical procedure, due to the extremely low ejection fraction, it was decided to include cardioprotective treatment with Levosimendan. The postoperative period was not straightforward but successful. In the monthly and five-month follow-up, a continuous improvement of heart function with normal renal function was noted.

Conclusions

Kidney transplantation in patients with lupus suffering from heart failure requires the involvement of a team of specialists. Patients with extremely low ejection fraction in the perioperative period should undergo careful hemodynamic supervision in the intensive care unit. Cardioprotective and thus nephroprotective Levosimendan therapy together with optimal fluid and hemodynamic therapy in the peri-transplant period may be a bridge for heart remodeling after kidney transplantation.

Initial Changes in the Heart Conduction System Illustrated by Difference Map Patterns in Adolescent Patients After Kidney Transplantation: A Pilot Study

BACKGROUND

Cardiovascular complications (CVCs) in patients with end-stage renal disease (ESRD) often require hospitalization and are associated with an increased risk of fatality. Although kidney transplantation (KTx) improves a patient's status, CVCs are still a serious risk factor, so early identification is very important for final therapeutic outcome.

METHODS

This study included 5 post-KTx patients (age, 20.8 ± 1.16 years), dialyzed before KTx, and followed up for 6.7 ± 1.71 years. Body surface potential mapping (BSPM) was performed 4 times: twice before and twice after KTx. Electrocardiographic data were processed into map plotting to illustrate differences in ventricular activation times (VATs).

RESULTS

A comparative analysis of difference maps, both of dialyzed patients and normal subjects, highlighted certain specificities in the distribution of VAT changes for the left anterior fascicle block (LAFB). The maps clearly showed a significant correlation between the intensity of changes and duration of dialysis before KTx. After KTx, VATs seemed to be similar to those in normal subjects; however, this was true only for patients dialyzed for <1 year. The patients dialyzed for >1 year showed persistent conduction abnormalities on their VAT maps.

CONCLUSION

Summary differences in VAT maps can enable diagnostics of initial activation propagation abnormalities in the heart. Short-term dialysis therapy before KTx imposes positive effects with regression of heart conduction changes. These observations need to be verified in a larger study population.

Evolution of Cardiovascular Disease During the Transition to End-Stage Renal Disease

Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD). The rate of death in incident dialysis patients remains high. This has led to interest in the study of the evolution of CVD during the critical transition period from CKD to ESRD. Understanding the natural history and risk factors of clinical and subclinical CVD during this transition may help guide the timing of appropriate CVD therapies to improve outcomes in patients with kidney disease. This review provides an overview of the epidemiology of subclinical and clinical CVD during the transition from CKD to ESRD and discusses clinical trials of CVD therapies to mitigate risk of CVD in CKD and ESRD patients.

The reverse remodeling of the aorta in patients after renal transplantation - the value of aortic stiffness index: prospective echocardiographic study

BACKGROUND

Atherosclerosis is regarded as a combination of two major separate diseases: atherosis and sclerosis. Sclerotic component depends on deterioration of elastic properties of the aortic wall and is called aortic stiffness. The most valuable, non-invasive method of aortic stiffness assessment is echocardiography, which allows to calculate the aortic stiffness index (ASI). ASI is an independent predictor of all-cause and cardiovascular mortality in different groups of patients. The main aim of study was the assessment of the aortic reverse remodeling in patients with end-stage renal disease (ESRD) after renal transplantation (RT).

METHODS

Study group involved 42 patients aged 43.3 ± 12.6 years, including 19 women aged 49.9 ± 10.9 years and 23 men aged 41.5 ± 12.91 years, who have undergone RT from non-related renal transplant donors, The study protocol has been consisted of 5 stages: 1 week after RT, 3 months after RT, 6 months after RT, 1 year after RT and 3 years after RT. The echocardiographic examination was performed and measurements of Ao_max, Ao_min were done. On the base of obtained parameters ASI, aortic distensibility (AD) and aortic strain (AS) were calculated according to adequate formulas.

RESULTS

The improvement of indices characterizing the elastic properties of aorta were noted. These changes attained the statistically significant level only at the end of the observation. ASI just after RT was equal - 4.65 ± 1.58, three months after RT - 4.54 ± 1.49, six months after RT - 4.59 ± 1.61, one year after RT - 4.35 ± 1.21 and three years after RT - 3.35 ± 1.29, while AD reached respectively - 6.55 ± 3.76 cm²/dyn^-110^-6 just after RT, - 6.38 ± 3.42 cm²/dyn^-110^-6 three months after RT, - 6.53 ± 3.60 cm²/dyn^-110^-6 six months after RT, - 6.48 ± 2.79 cm²/dyn^-110^-6 one year after RT and - 8.03 ± 3.95 cm²/dyn^-110^-6 three years after RT. Noted AS values were equal - 6.61 ± 4.05%, just after RT, - 6.40 ± 3.58% three months after RT, - 6.56 ± 3.76%, six months after RT, - 6.45 ± 2.80% one year after RT, - 8.01 ± 3.97%. and three years after RT. The exact analysis of parameters concerning aortic function showed that to achieve ASI, AD and AS improvement, long time was needed, because the most significant changes of these indices were observed only between 1 year and 3 years after RT.

CONCLUSIONS

There is a relationship between renal transplantation and improvement of the aortic elastic properties. The recovery of the renal function allows to initiate the reparative processes leading to at least partial restitution of the structure and features of the aorta, which is called reverse remodelling. Improvement of aortic wall elastic properties after renal transplantation is a continuous and prolonged process.

Kidney transplantation in children with decreased left ventricular systolic function: a Midwest Pediatric Nephrology Consortium study

BACKGROUND

Left ventricular (LV) systolic dysfunction is a relatively uncommon but serious complication of pediatric chronic kidney disease, and may be related to uremia and uncontrolled hypertension. There is limited information on the strategy for managing these children. In some cases, combined heart-kidney transplant may be considered or kidney transplant delayed until cardiac function improves. It is unknown whether these patients are at increased risk for poor outcomes after kidney transplantation.

METHODS

We conducted a retrospective, multicenter study on the outcomes of children with severe and symptomatic cardiomyopathy who underwent kidney transplantation.

RESULTS

Eleven patients receiving maintenance dialysis with systolic dysfunction underwent kidney transplantation without simultaneous heart transplant. Nine patients had congestive heart failure in the pre-transplant period. There were no identified complications post-transplant related to the underlying cardiac dysfunction. LV systolic function normalized in all patients and the mean shortening fraction increased from 19.0 ± 4.6 % to 32.0 ± 4.4 % (p < 0.0001).

CONCLUSIONS

Kidney transplantation should be considered for children receiving maintenance dialysis with severe LV dysfunction.

Dynamics of changes in heart conduction system in dialyzed young adults after kidney transplantation--pilot study

BACKGROUND

Cardiovascular complications are the main clinical problem in patients with end-stage renal failure (ESRF). After successful kidney transplantation, this situation improves, although cardiovascular complications remain a risk factor for increased mortality in these patients; therefore, their early identification is of key therapeutic and prognostic significance. This study was designed to determine a dynamics of changes in the heart conduction system in hemodialyzed young adult patients after kidney transplantation in a long-term follow-up, based on the body surface potential mapping (BSPM) method.

METHODS

The study comprised 5 patients (mean age, 20.8 ± 1.16 years) after kidney transplantation (KT) who had been chronically dialyzed before. The mean observation period was 6.7 ± 1.71 years. All of the patients were submitted to the following examinations before and after KT: 12-lead electrocardiography (ECG), echocardiography, standard biochemistry, and BSPM (isochronous maps). The mean creatinine concentration was 1.38 ± 0.05 mg/dL. The control group comprised 30 healthy persons.

RESULTS

BSPM maps taken from the dialyzed patients demonstrated disturbed spreading of electric impulses within the heart ventricles in a type of left bundle branch block, despite normal 12-lead ECG and echocardiography results. A relationship was demonstrated between the BSPM changes and dialysis duration. After KT, the abnormal distribution of isochrones and ventricular activation times (VAT) presented some significant and specific regression.

CONCLUSIONS

1) In dialyzed patients, BSPM is a more sensitive method than ECG and enables early identification of changes in the heart conduction system presented as left bundle branch block. 2) Dialysotherapy duration before and after KT determines the extent of the BSPM changes. 3) Successful effects of KT bring about regression of intraventricular conduction disorders. 4) The observations need verification in a larger patient group.

Increased procollagen type I C-terminal peptide levels indicate diastolic dysfunction in end-stage renal disease patients undergoing maintenance dialysis therapy

BACKGROUND

Cardiac dysfunction is common among patients with end-stage renal disease. The aim of this study was to explore the determinants of diastolic dysfunction in patients with end-stage renal disease on maintenance hemodialysis.

METHODS

Patients with asymptomatic end-stage renal disease undergoing hemodialysis underwent Doppler tissue imaging analysis and two-dimensional speckle-tracking echocardiography with strain analysis. Blood studies included albumin, cardiac troponin T, and procollagen type I C-terminal peptide (PICP).

RESULTS

All enrolled patients had left ventricular (LV) diastolic dysfunction and were stratified into two groups by a cutoff value of 13 for the ratio of early transmitral flow velocity to the average early diastolic annular velocity (E/e'). Seventy-two of the enrolled patients (87%) had grade 1 diastolic dysfunction, and 11 patients (13%) had higher grades of diastolic dysfunction. The study population did not include a representative sample of patients with the pseudonormal or restrictive filling patterns of diastolic dysfunction. There were no significant differences in gender, age, LV geometric change, ejection fraction, global systolic longitudinal strain and strain rate, and prevalence of comorbidities between groups. Patients with average E/e' ≥ 13 had higher PICP, which was significantly correlated with cardiac troponin T, average E/e', and systolic circumferential strain rate. By multivariate regression analysis, average E/e' level was an independent factor of PICP level (P = .047).

CONCLUSIONS

Hemodialysis patients with high average E/e' ratios showed increased levels of LV filling pressure and higher severity levels of cardiac fibrosis, which occurred before the development of systolic dysfunction. PICP was a potential indicator of diastolic dysfunction and increased LV filling pressure.

Cardiovascular risk assessment among potential kidney transplant candidates: approaches and controversies

Cardiovascular disease is the most common cause of death after kidney transplantation. However, uncertainties regarding the optimal assessment of cardiovascular risk in potential transplant candidates have produced controversy and inconsistency in pretransplantation cardiac evaluation practices. In this review, we consider the evidence supporting cardiac evaluation in kidney transplant candidates, generally focused on coronary artery disease, according to the World Health Organization principles for screening. The importance of pretransplant cardiac evaluation is supported by the high prevalence of coronary artery disease and the incidence and adverse consequences of acute coronary syndromes in this population. Testing for coronary artery disease may be performed noninvasively by using modalities that include nuclear myocardial perfusion studies and dobutamine stress echocardiography. These tests have prognostic value for mortality, but imperfect sensitivity and specificity for detecting angiographically defined coronary artery disease in patients with end-stage renal disease. Associations of angiographically-defined coronary artery disease with subsequent survival also are inconsistent, likely because plaque instability is more critical for infarction risk than angiographic stenosis. The efficacy and best methods of myocardial revascularization have not been examined in large contemporary clinical trials in patients with end-stage renal disease. Biomarkers, such as cardiac troponin, have prognostic value in end-stage renal disease, but require further study to determine clinical applications in directing more expensive and invasive cardiac evaluation.

Severe left ventricular systolic dysfunction may reverse with renal transplantation: uremic cardiomyopathy and cardiorenal syndrome

Chronic heart failure (CHF) and chronic kidney disease (CKD) are serious medical conditions with significant morbidity and mortality. Emerging evidence indicates that the function of these two organ systems are affected by each other in a complex interplay. Most patients with CKD suffer frequently from cardiac abnormalities including left ventricular hypertrophy (LVH), left ventricular dilatation (LVD), left ventricular (LV) diastolic and/or systolic dysfunction. Although previously thought that LV systolic dysfunction was an absolute contraindication to renal transplantation, several observational studies have shown this not to be true and that transplantation can lead to significant improvement in LV systolic function. Furthermore, correction of the uremic state by renal transplantation leads to improvement of LVD and possibly regression of LVH. In fact, the reduction of LVH postkidney transplantation was shown to be dependent on adequate renal function and hypertension control. Diabetes mellitus does not seem to be a confounding factor in the improvement of uremic cardiomyopathy with renal transplantation.