Cardiovascular events following renal transplantation: role of traditional and transplant-specific risk factors

Gender differences in cardiovascular outcomes of kidney transplant recipients: A retrospective cohort study

The purpose of this study was to investigate gender differences in cardiovascular outcomes of kidney transplant recipients (KTRs). Here, a retrospective cohort study was conducted, and data from the National Health Insurance Research Database in Taiwan were used. In total, 2904 patients who had end-stage renal disease (ERSD) and received kidney transplantation (KT) were identified by propensity score matching (PSM) and were enrolled from 1997 to 2012, with follow-up ending in 2013. Besides, major adverse cardiovascular events (MACEs) were defined as a composite of all-cause mortality, nonfatal myocardial infarction, and nonfatal strokes. Apart from that, hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated by Cox regression, while the Bayesian network model was constructed to assess the importance of risk factors for MACEs. Furthermore, the original cohort was a sensitivity analysis. Women had a lower risk of MACEs compared with men (hazard ratio [HR]: 0.84; 95% CI: 0.72-0.98; P = .024). Beyond that, stratified analysis of age and waiting time for KT showed that the risk of MACEs was significantly lower in women than in men among KTRs aged > 50 years (HR: 0.79; 95% CI: 0.62-1.0; P = .05) or waiting time for KT ≤ 6 years (HR: 0.85; 95% CI: 0.72-0.99; P = .04). Bayesian network indicated that age is an important determinant of cardiovascular outcomes in KTRs, regardless of gender. In Taiwan, women had a lower risk of adverse cardiovascular outcomes than men in KTRs aged > 50 years or with a waiting time for KT ≤ 6 years. Furthermore, age is an important independent determinant for the prognosis of KTRs.

Expanded Hemodialysis ameliorates uremia-induced impairment of vasculoprotective KLF2 and concomitant proinflammatory priming of endothelial cells through an ERK/AP1/cFOS-dependent mechanism

Aims

Expanded hemodialysis (HDx) therapy with improved molecular cut-off dialyzers exerts beneficial effects on lowering uremia-associated chronic systemic microinflammation, a driver of endothelial dysfunction and cardiovascular disease (CVD) in hemodialysis (HD) patients with end-stage renal disease (ESRD). However, studies on the underlying molecular mechanisms are still at an early stage. Here, we identify the (endothelial) transcription factor Krüppel-like factor 2 (KLF2) and its associated molecular signalling pathways as key targets and regulators of uremia-induced endothelial micro-inflammation in the HD/ESRD setting, which is crucial for vascular homeostasis and controlling detrimental vascular inflammation.

Methods and results

First, we found that human microvascular endothelial cells (HMECs) and other typical endothelial and kidney model cell lines (e.g. HUVECs, HREC, and HEK) exposed to uremic serum from patients treated with two different hemodialysis regimens in the Permeability Enhancement to Reduce Chronic Inflammation II (PERCI-II) crossover clinical trial - comparing High-Flux (HF) and Medium Cut-Off (MCO) membranes - exhibited strongly reduced expression of vasculoprotective KLF2 with HF dialyzers, while dialysis with MCO dialyzers led to the maintenance and restoration of physiological KLF2 levels in HMECs. Mechanistic follow-up revealed that the strong downmodulation of KLF2 in HMECs exposed to uremic serum was mediated by a dominant engagement of detrimental ERK instead of beneficial AKT signalling, with subsequent AP1-/c-FOS binding in the KLF2 promoter region, followed by the detrimental triggering of pleiotropic inflammatory mediators, while the introduction of a KLF2 overexpression plasmid could restore physiological KLF2 levels and downmodulate the detrimental vascular inflammation in a mechanistic rescue approach.

Conclusion

Uremia downmodulates vasculoprotective KLF2 in endothelium, leading to detrimental vascular inflammation, while MCO dialysis with the novel improved HDx therapy approach can maintain physiological levels of vasculoprotective KLF2.

Is Erythrocytosis More Common After Simultaneous Pancreas Kidney Transplantation? A Single-Center Experience

Post-transplant erythrocytosis (PTE) is reported in 8% to 22% of kidney transplant recipients. Few studies have evaluated the prevalence of PTE in simultaneous kidney-pancreas transplantation (SPKT). This study aimed to evaluate the prevalence of PTE in a cohort of SPKT and same-donor single kidney transplant patients and find predictive factors for erythrocytosis development. A single-center retrospective cohort study was performed with 65 SPKT recipients and 65 same-donor single kidney transplant patients. Post-transplant erythrocytosis was defined as a hematocrit persistently >51% without a known cause of erythrocytosis. The PTE prevalence was 23.1% and was more frequent in SPKT patients than in single donor patients (38.5% vs 7.7%; P < .001). The mean time for PTE development was 11.2 ± 13.3 months. In the multivariate model, SPKT was the only predictor for PTE development. De novo hypertension was more frequent in the PTE group (P = .002), but there was no difference in stroke and pancreatic or kidney thrombosis occurrence. Post-transplant erythrocytosis is more common after SPKT than after single kidney transplantation. De novo hypertension was more frequent in the erythrocytosis group, but allograft thrombosis rates.

The effect of calcineurin inhibitors on anthropometric measurements in kidney transplant recipients

Background

This study was designed to investigate the effect of calcineurin inhibitors (CNIs), cyclosporine (CsA), and tacrolimus (Tac) on anthropometrics in kidney transplant recipients.

Methods

111 of 128 adult kidney transplant recipients who received post-transplant CNIs were included in this retrospective study. Anthropometrics were recorded in the pre-transplant and post-transplant 4-year follow-up periods (1st, 3rd, 6th, 12th, 24th, 36th and 48th months).

Results

Compared to pre-transplant values, significant increases in body weight and body mass index (between 3rd and 48th months), waist and hip circumferences (between 1st and 48th months), waist-to-hip ratio (between 1st and 3rd or 6th months) and neck circumference (between 1st and 12th or 24th months) were observed in both CsA and Tac groups. A significant increase was noted in post-transplant body fat percentage values for the 3rd to 24th months in the CsA group, whereas for the 24th to 48th months in both CsA and Tac groups. Hip circumferences percentage changes from the pre-transplant period to the 1st, 12th and 24th months were significantly higher in CsA than in the Tac group. At each time point, there was no significant difference in percentage changes for other anthropometric parameters between the CsA and Tac groups. De novo diabetes mellitus developed in 8.3% of the CsA group and 19.1% of the Tac group.

Conclusions

After a successful kidney transplant, anthropometric measurements increase in most recipients. Although the effect of calcineurin inhibitor type on weight gain is unclear, a regression analysis showed that CNI type was not a risk factor for the development of obesity in the 48th month. However, it is helpful to be cautious about its dyslipidemic effect in patients using CsA and the potential hazards of using Tac in patients with a diabetic predisposition.

Clinical Implementation of Different Strategies for Exercise-Based Rehabilitation in Kidney and Liver Transplant Recipients: A Pilot Study

Fundamento:

A doença cardiovascular está entre as principais causas de morte entre pacientes transplantados. Embora esses pacientes possam teoricamente se beneficiar de programas de reabilitação baseada em exercícios (RBE), sua implementação ainda é um desafio.

Objetivo:

Apresentamos nossa experiência inicial em diferentes modos de realização de um programa piloto de RBE em receptores de transplante de rim e fígado.

Métodos:

Trinta e dois pacientes transplantados renais ou hepáticos foram convidados para um programa de RBE de 6 meses realizado na academia do hospital, na academia comunitária ou em casa, de acordo com a preferência do paciente. O nível de significância adotado foi de 5%.

Resultados:

Dez pacientes (31%) não completaram o programa. Entre os 22 que completaram, 7 treinaram na academia do hospital, 7 na academia comunitária e 8 em casa. O efeito geral foi um aumento de 11,4% nos METs máximos (tamanho do efeito de Hedges g = 0,39). O grupo de academia hospitalar teve um aumento nos METs de 25,5% (g = 0,58, tamanho de efeito médio) versus 10% (g = 0,25) e 6,5% (g = 0,20) para os grupos de academia comunitária e em casa, respectivamente. Houve efeito benéfico nas pressões arteriais sistólica e diastólica, maior para os grupos academia hospitalar (g= 0,51 e 0,40) e academia comunitária (g= 0,60 e 1,15) do que para os pacientes treinando em casa (g= 0,07 e 0,10). Nenhum evento adverso significativo foi relatado durante o seguimento.

Conclusão:

Programas de RBE em receptores de transplante de rim e fígado devem ser incentivados, mesmo que sejam realizados fora da academia do hospital, pois são seguros com efeitos positivos na capacidade de exercício e nos fatores de risco cardiovascular.

Morning blood pressure surge in renal transplant recipients: Its relation to graft function and arterial stiffness

BACKGROUND

When the blood pressure rises before awakening in the morning, it is called as morning blood pressure pulse (MBPS). MBPS is considered to be an independent risk factor for cardiovascular disease. The aim of this study was to investigate the associations between MBPS, graft function, arterial stiffness and echocardiographic indicies in renal transpant recipients.

METHODS

Among 600 renal transplant recipients, 122 patients who had a history of hypertension and were taking at least one antihypertensive medication were enrolled in the study. Arterial stiffness was measured by carotid-femoral pulse wave velocity (PWv), and echocardiographic indicies were assessed. 24 hour ambulatory blood pressure was monitored for all patients. MBPS was calculated by substracting morning systolic blood pressure from minimal asleep systolic blood pressure.

RESULTS

Mean morning, day time and asleep systolic blood pressure values were 171.2± 23.9, 137.9± 18.1, and 131.7 ± 18.9 respectively. Non-dipper hypertention status was observed in 93 patients. Mean MBPS was 35.6 ± 19.5 mm Hg, mean PWv was 6.5 ± 2.0 m/sec. Patients with MBPS ≥ 35 mm Hg, had significantly lower eGFR and higher proteinuria, PWv. higher left atrium volume and LVMI. In regression analysis, day time systolic blood pressure, asleep systolic blood pressure, morning blood pressure surge, non-dipper status and left ventricular mass index were detected as the predictors of graft function.

CONCLUSIONS

Increased morning blood pressure surge is associated with graft dysfunction, increased arterial stiffness and LVMI that contributes to cardiovascular mortality and morbidity in renal transplant recipients. This article is protected by copyright. All rights reserved.

Kidney transplantation waiting times and risk of cardiovascular events and mortality: a retrospective observational cohort study in Taiwan

OBJECTIVES

Patients with end-stage renal disease (ESRD) are at a high risk of cardiovascular events (CVEs), and kidney transplantation (KT) has been reported to improve risk of CVEs and survival. As the association of KT timing on long-term survival and clinical outcomes remains unclear, we investigated the association of different KT waiting times with clinical outcomes.

DESIGN

Retrospective observational cohort study.

SETTING

We conducted an observational cohort study using data from the National Health Insurance Research Database in Taiwan. Adult patients who initiated KT therapy from 1997 to 2013 were included.

PARTICIPANTS

A total of 3562 adult patients who initiated uncomplicated KT therapy were included and categorised into four groups according to KT waiting times after ESRD: group 1 (<1 year), group 2 (1-3 years), group 3 (3-6 years) and group 4 (>6 years).

PRIMARY OUTCOME MEASURES

The main outcomes were composite of all-cause death, non-fatal myocardial infarction or non-fatal stroke, based on the primary diagnosis in medical records during hospitalisation.

RESULTS

Compared with group 1, the adjusted risk of primary outcome events (all-cause death, non-fatal myocardial infarction or non-fatal stroke) increased by 1.67 times in group 2 (95% CI: 1.40 to 2.00; p<0.001), 2.17 times in group 3 (95% CI: 1.73 to 2.71; p<0.001) and 3.10 times in group 4 (95% CI: 2.21 to 4.35; p<0.001). The rates of primary outcome events were 6.7%, 13.4% and 14.0% within 5 years, increasing to 19.5%, 26.3% and 30.8% within 10 years in groups 1, 2 and 3, respectively.

CONCLUSIONS

Our results demonstrate that early KT is associated with superior long-term cardiovascular outcomes compared with late KT in selected patients with ESRD receiving uncomplicated KT, suggesting that an early KT could be a better treatment option for patients with ESRD who are eligible for transplantation.

Feasibility and acceptability of high-intensity interval training and moderate-intensity continuous training in kidney transplant recipients: the PACE-KD study

Background

Kidney transplant recipients (KTRs) exhibit unique elevated inflammation, impaired immune function, and increased cardiovascular risk. Although exercise reduces cardiovascular risk, there is limited research on this population, particularly surrounding novel high-intensity interval training (HIIT). The purpose of this pilot study was to determine the feasibility and acceptability of HIIT in KTRs.

Methods

Twenty KTRs (male 14; eGFR 58±19 mL/min/1.73 m²; age 49±11 years) were randomised and completed one of three trials: HIIT A (4-, 2-, and 1-min intervals; 80–90% watts at V̇O_2peak), HIITB (4×4 min intervals; 80–90% V̇O_2peak) or MICT (~40 min; 50–60% V̇O_2peak) for 24 supervised sessions on a stationary bike (approx. 3x/week over 8 weeks) and followed up for 3 months. Feasibility was assessed by recruitment, retention, and intervention acceptability and adherence.

Results

Twenty participants completed the intervention, and 8 of whom achieved the required intensity based on power output (HIIT A, 0/6 [0%]; HIITB, 3/8 [38%]; MICT, 5/6 [83%]). Participants completed 92% of the 24 sessions with 105 cancelled and rescheduled sessions and an average of 10 weeks to complete the intervention. Pre-intervention versus post-intervention V̇O_2peak (mL/kg^-1/min^-1) was 24.28±4.91 versus 27.06±4.82 in HIITA, 24.65±7.67 versus 27.48±8.23 in HIIT B, and 29.33±9.04 versus 33.05±9.90 in MICT. No adverse events were reported.

Conclusions

This is the first study to report the feasibility of HIIT in KTRs. Although participants struggled to achieve the required intensity (power), this study highlights the potential that exercise has to reduce cardiovascular risk in KTRs. HIIT and MICT performed on a cycle, with some modification, could be considered safe and feasible in KTRs. Larger scale trials are required to assess the efficacy of HIIT in KTRs and in particular identify the most appropriate intensities, recovery periods, and session duration. Some flexibility in delivery, such as incorporating home-based sessions, may need to be considered to improve recruitment and retention.

Trial registration

ISRCTN, ISRCTN17122775. Registered on 30 January 2017.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-022-01067-3.

The Utility of Pre- and Post-Transplant Oral Glucose Tolerance Tests: Identifying Kidney Transplant Recipients With or at Risk of New Onset Diabetes After Transplant

Background: New onset diabetes after transplant (NODAT) is common in kidney transplant recipients (KTRs). Identifying patients at risk prior to transplant may enable strategies to mitigate NODAT, with a pre-transplant oral glucose tolerance test (OGTT) suggested by the KDIGO 2020 Guidelines for this purpose.

Methods: We investigated the utility of pre- and post-transplant OGTTs to stratify risk and diagnose NODAT in a retrospective, single-centre cohort study of all non-diabetic KTRs transplanted between 2003 and 2018.

Results: We identified 597 KTRs who performed a pre-transplant OGTT, of which 441 had their post-transplant glycaemic status determined by a clinical diagnosis of NODAT or OGTT. Pre-transplant dysglycaemia was identified in 28% of KTRs and was associated with increasing age (p < 0.001), BMI (p = 0.03), and peritoneal dialysis (p < 0.001). Post-transplant dysglycaemia was common with NODAT and impaired glucose tolerance (IGT) occurring in 143 (32%) and 121 (27%) patients, respectively. Pre-transplant IGT was strongly associated with NODAT development (OR 3.8, p < 0.001).

Conclusion: A pre-transplant OGTT identified candidates at increased risk of post-transplant dysglycaemia and NODAT, as diagnosed by an OGTT. Robust prospective trials are needed to determine whether various interventions can reduce post-transplant risk for candidates with an abnormal pre-transplant OGTT.

Risk of post-transplant cardiovascular events in kidney transplant recipients with preexisting aortoiliac stenosis

Prediction of the risk of cardiovascular events (CVE's) is important to optimize outcomes after kidney transplantation. Aortoiliac stenosis is frequently observed during pre‐transplant screening. We hypothesized that these patients are at higher risk of post‐transplant CVE's due to the joint underlying atherosclerotic disease. Therefore, we aimed to assess whether aortoiliac stenosis was associated with post‐transplant CVE's. This retrospective, single‐center cohort study included adult kidney transplant recipients, transplanted between 2000 and 2016, with contrast‐enhanced imaging available. Aortoiliac stenosis was classified according to the Trans‐Atlantic Inter‐Society Consensus (TASC) II classification and was defined as significant in case of ≥50% lumen narrowing. The primary outcome was CVE‐free survival. Eighty‐nine of 367 patients had significant aortoiliac stenosis and were found to have worse CVE‐free survival (median CVE‐free survival: stenosis 4.5 years (95% confidence interval (CI) 2.8–6.2), controls 8.9 years (95% CI 6.8–11.0); log‐rank test P < .001). TASC II C and D lesions were independent risk factors for a post‐transplant CVE with a hazard ratio of 2.15 (95% CI 1.05–4.38) and 6.56 (95% CI 2.74–15.70), respectively. Thus, kidney transplant recipients with TASC II C and D aortoiliac stenosis require extensive cardiovascular risk management pre‐, peri,‐ and post‐transplantation.

Impact of recipient and donor smoking in living-donor kidney transplantation: a prospective multicenter cohort study

The smoking status of kidney transplant recipients and living donors has not been explored concurrently in a prospective study, and the synergistic adverse impact on outcomes remains uncertain. The self-reported smoking status and frequency were obtained from recipients and donors at the time of kidney transplantation in a prospective multicenter longitudinal cohort study (NCT02042963). Smoking status was categorized as "ever smoker" (current and former smokers collectively) or "never smoker." Among 858 eligible kidney transplant recipients and the 858 living donors, 389 (45.3%) and 241 (28.1%) recipients were considered ever smokers at the time of transplant. During the median follow-up period of 6 years, the rate of death-censored graft failure was significantly higher in ever-smoker recipients than in never-smoker recipients (adjusted HR, 2.82; 95% CI 1.01-7.87; P = 0.048). A smoking history of >20 pack-years was associated with a significantly higher rate of death-censored graft failure than a history of ≤20 pack-years (adjusted HR, 2.83; 95% CI 1.19-6.78; P = 0.019). No donor smoking effect was found in terms of graft survival. The smoking status of the recipients and donors or both did not affect the rate of biopsy-proven acute rejection, major adverse cardiac events, all-cause mortality, or post-transplant diabetes mellitus. Taken together, the recipient's smoking status before kidney transplantation is dose-dependently associated with impaired survival.

Inferior outcomes following cardiac surgery in patients with a functioning renal allograft

OBJECTIVES

Renal transplantation is an effective treatment for end-stage renal failure. The aim of this study was to evaluate outcomes for these patients undergoing cardiac surgery.

METHODS

A retrospective analysis identified patients with a functioning renal allograft at the time of surgery. A 2:1 propensity matching was performed. Patients were matched on: age, sex, left ventricle function, body mass index, preoperative creatinine, operation priority, operation category and logistic EuroSCORE.

RESULTS

Thirty-eight patients undergoing surgery with a functioning renal allograft were identified. The mean age was 62.4 years and 66% were male. A total of 44.7% underwent coronary artery bypass grafting and 26.3% underwent a single valve procedure. The mean logistic EuroSCORE was 10.65. The control population of 76 patients was well matched. Patients undergoing surgery following renal transplantation had a prolonged length of intensive care unit (3.19 vs 1.02 days, P < 0.001) and hospital stay (10.3 vs 7.17 days, P = 0.05). There was a higher in-hospital mortality (15.8% vs 1.3%, P = 0.0027). Longer-term survival on Kaplan-Meier analysis was also inferior (P < 0.001). One-year survival was 78.9% vs 96.1% and 5-year survival was 63.2% vs 90.8%. A further subpopulation of 11 patients with a failed renal allograft was identified and excluded from the main analysis; we report demographic and outcome data for them.

CONCLUSIONS

Patients with a functioning renal allograft are at higher risk of perioperative mortality and inferior long-term survival following cardiac surgery. Patients in this population should be appropriately informed at the time of consent and should be managed cautiously in the perioperative period with the aim of reducing morbidity and mortality.

Post-transplant erythrocytosis after kidney transplantation: A review

Post-transplant erythrocytosis (PTE) is defined as persistently elevated hemoglobin > 17 g/dL or hematocrit levels > 51% following kidney transplantation, independent of duration. It is a relatively common complication within 8 months to 24 months post-transplantation, occurring in 8%-15% of kidney transplant recipients. Established PTE risk factors include male gender, normal hemoglobin/hematocrit pre-transplant (suggestive of robust native kidney erythropoietin production), renal artery stenosis, patients with a well-functioning graft, and dialysis before transplantation. Many factors play a role in the development of PTE, however, underlying endogenous erythropoietin secretion pre-and post-transplant is significant. Other contributory factors include the renin-angiotensin- aldosterone system, insulin-like growth factors, endogenous androgens, and local renal hypoxia. Most patients with PTE experience mild symptoms like malaise, headache, fatigue, and dizziness. While prior investigations showed an increased risk of thromboembolic events, more recent evidence tells a different story-that PTE perhaps has lessened risk of thromboembolic events or negative graft outcomes than previously thought. In the evaluation of PTE, it is important to exclude other causes of erythrocytosis including malignancy before treatment. Angiotensin converting enzyme inhibitors (ACE-I) and angiotensin receptor blockers (ARBs) are the mainstays of treatment. Increased ACE-I/ARB use has likely contributed to the falling incidence of erythrocytosis. In this review article, we summarize the current literature in the field of post-transplant erythrocytosis after kidney transplantation.

Limited Predictive Role of the Revised Cardiac Risk Index in Kidney Transplant: Single Center Evaluation and Comparison With International Literature

Perioperative risk factors predicting major cardiovascular events (MACE) and the performance of the Revised Cardiac Risk Index (RCRI) in a retrospective cohort of 325 consecutive adult patients undergoing kidney transplant from deceased donor grafts were assessed. Primary outcome was a composite of MACE up to 30 days post-transplant. Incidence of MACE was 5.8% at 30 days. Overall proportion of patients with RCRI ≥ 4 was 5%, but was higher (28%) among those who developed MACE. Patients with RCRI ≥ 4 had lower survival free of MACE compared to those with RCRI < 4 (P <0.001); however, in multivariable analysis, RCRI was not a predictor of cardiovascular events. The RCRI demonstrated poor discrimination to predict MACE at 30 days [area under the curve 0.64 (95% CI 0.49-0.78)]. Revised Cardiac Risk Index was not associated with reduced MACE-free survival adjusted analysis and its predictive ability was poor.

Working towards an ERAS Protocol for Pancreatic Transplantation: A Narrative Review

Enhanced recovery after surgery (ERAS) initially started in the early 2000s as a series of protocols to improve the perioperative care of surgical patients. They aimed to increase patient satisfaction while reducing postoperative complications and postoperative length of stay. Despite these protocols being widely adopted in many fields of surgery, they are yet to be adopted in pancreatic transplantation: a high-risk surgery with often prolonged length of postoperative stay and high rate of complications. We have analysed the literature in pancreatic and transplantation surgery to identify the necessary preoperative, intra-operative and postoperative components of an ERAS pathway in pancreas transplantation.

Early postoperative acute myocardial infarction in kidney transplant recipients: A nested case-control study

INTRODUCTION

The epidemiology of early acute myocardial infarctions after kidney transplantation has not been well characterized. This study sought to examine the incidence, risk factors, and clinical outcomes of early acute myocardial infarctions or EAMI in kidney transplant recipients.

METHODS

A total of 1976 patients who underwent kidney transplantation at our center from Jan 1, 2000, to Sept 30, 2016, were included. A nested case-control design was used to study EAMI risk factors using a conditional logistic regression model. A Cox proportional hazards model was used to assess the association of EAMI with death-censored graft failure, death with graft function, and total graft failure.

RESULTS

Seventy four patients had an EAMI within 3 months post-transplant. Based on univariable analyses, risk factors for EAMI included age and recipient history of diabetes mellitus or coronary artery disease. After adjustment, recipient history of coronary artery disease was the only independent predictor for EAMI (OR 3.76, p < .001). Patients who experienced EAMI were more likely to experience death-censored graft failure, death with graft function, and total graft failure.

CONCLUSION

While the incidence of EAMI in kidney transplant recipients is relatively low, these data show that EAMI has profound long-term effects on morbidity and mortality.

Early cardiovascular events and cardiovascular death after renal transplantation: role of pretransplant risk factors

BACKGROUND

The purpose of this study was to verify the risk factors present in patients on the kidney transplant waiting list that may interfere with the incidence of cardiovascular (CV) events and death during the first 12 months after transplantation.

METHODS

Based on the data collected prospectively during pretransplant workups, a retrospective study was conducted including 665 patients followed up until death or completing 12 months posttransplantation. Endpoints were the composite incidence of CV events and death.

RESULTS

The prevalence of diabetes, LV hypertrophy, and CV disease at baseline was high; 14% of patients had angina, 26% an abnormal myocardial scan, and 47% coronary artery disease. CV events occurred in 53 patients (8.4%) and in 29 (55%) caused death. The independent predictors of events were age ≥ 50 years (HR 2.292; CI% 1.093-4.806), angina (HR 1.969; CI% 1.039-3.732), and altered myocardial scan (HR 1.905, CI% 1.059-3.428). Altered myocardial scan (HR 2.822, 95% CI 1.095-6.660) was also one of the independent predictor of CV death.

CONCLUSION

The incidence of CV events and death were predicted by variables associated with myocardial ischemia, a potentially modifiable risk factor. Patients with pretransplantation myocardial ischemia should be considered at a higher risk of developing early CV complications and managed accordingly before, during, and after kidney transplantation.

Safety and efficacy of catheter ablation for atrial fibrillation in abdominal solid organ (renal and hepatic) transplant recipients: A single-center pilot experience

BACKGROUND

Atrial fibrillation (AF) is common in abdominal solid organ transplant recipients and a cause of morbidity and mortality in this population. However, the outcomes of catheter ablation (CA) in transplant recipients with AF remain unclear. This study aimed to elucidate the outcomes of CA in renal and hepatic transplant recipients.

METHODS AND RESULTS

Between 2015 and 2019, 14 transplant recipients (nine with kidney transplantation and five with liver transplantation) were enrolled from among 10,741 AF patients and underwent CA at Anzhen Hospital. Another 56 patients matched by age, sex, and AF type were selected as the control group (four controls for each transplant recipient). During a mean follow-up of 30.0 ± 13.3 months after the initial procedure, 10 (71.4%) of the transplant patients, compared to 41 (73.2%) of the control patients, remained free from AF recurrence (p = 1.000). A repeated procedure was performed in one transplant patient and in six control subjects. Consequently, 11 (78.6%) of the transplant patients, compared to 46 (82.1%) of controls, were in sinus rhythm after the repeated ablation (p = .715). Notably, Kaplan-Meier analysis did not demonstrate any significant differences in the atrial arrhythmia-free rate after the initial and repeated procedure between the two groups. Vascular complications were identified in one transplant patient and two control subjects, while no life-threatening complications were observed in either group. There was no transient allograft dysfunction in transplant recipients after CA.

CONCLUSION

CA is safe and effective in abdominal solid transplant recipients, and maybe an optimal therapeutic strategy for this group.

A critical review of the relationship between post-transplant atherosclerotic events and cytomegalovirus exposure in kidney transplant recipients

Introduction: Cytomegalovirus (CMV) infection after kidney transplantation (KT) has been implicated in the so-called 'indirect effects' attributable to the viral ability to evade host's immunity and trigger sustained inflammation. Whether CMV exposure contributes to the development of post-transplant atherosclerotic events (AEs) remains controversial.Areas covered: This review (based on a PubMed/MEDLINE search from database inception to October 2019) summarizes the proposed mechanisms for the role of CMV in atherogenesis, including accelerated immunosenescence, endothelial injury and inflammatory milieu in the vessel wall. Sero-epidemiological evidence linking CMV exposure and cardiovascular disease in the general population is discussed. Finally, we performed a comprehensive review of observational studies investigating the impact of CMV infection on the occurrence of AE after KT, as well as the potential protective effect of antiviral prophylaxis.Expert opinion: Reviewed studies provide biological plausibility and preliminary clinical evidence pointing to the pathogenic role of CMV in post-transplant atherogenesis. However, no definitive recommendations can be made regarding the use of antiviral prophylaxis to prevent post-transplant AE, since existing evidence is mainly founded on inadequately powered post hoc analysis. Well-designed observational studies should clarify the differential impact of prophylactic or preemptive approaches on the occurrence of CMV-associated post-transplant AE among KT recipients.

Waiting List and Kidney Transplant Vascular Risk: An Ongoing Unmet Concern

BACKGROUND

Chronic kidney disease (CKD) is an important independent risk factor for adverse cardiovascular events in patients waitlisted for kidney transplantation (KT). Although KT reduces cardiovascular risk, these patients still have a higher all-cause and cardiovascular mortality than the general population. This concerning situation is due to a high burden of traditional and nontraditional risk factors as well as uremia-related factors and transplant-specific factors, leading to 2 differentiated processes under the framework of CKD, atherosclerosis and arteriosclerosis. These can be initiated by insults to the vascular endothelial endothelium, leading to vascular calcification (VC) of the tunica media or the tunica intima, which may coexist. Several pathogenic mechanisms such as inflammation-related endothelial dysfunction, mineral metabolism disorders, activation of the renin-angiotensin system, reduction of nitric oxide, lipid disorders, and the fibroblast growth factor 23-klotho axis are involved in the pathogenesis of atherosclerosis and arteriosclerosis, including VC.

SUMMARY

This review focuses on the current understanding of atherosclerosis and arteriosclerosis, both in patients on the waiting list as well as in kidney transplant recipients, emphasizing the cardiovascular risk factors in both populations and the inflammation-related pathogenic mechanisms. Key Message: The importance of cardiovascular risk factors and the pathogenic mechanisms related to inflammation in patients waitlisted for KT and kidney transplant recipients.

Effects of Smoking on Solid Organ Transplantation Outcomes

Tobacco smoking is the leading preventable cause of death worldwide. Both donor and recipient smoking have been shown to increase graft loss and mortality in solid organ transplant recipients in many studies. Only in lung transplants is smoking a universal contraindication to transplantation. Transplant centers implement different policies regarding smoking recipients and allografts from smoking donors. Due to scarcity of available allografts, the risks of smoking have to be weighed against the risks of a longer transplant waitlist period. Although transplant centers implement different strategies to encourage smoking cessation pre- and post-transplant, not many studies have been published that validate the efficacy of smoking cessation interventions in this vulnerable population. This article summarizes the results of studies investigating prevalence, impact on outcomes, and cessationinterventions for smoking in the transplant population. We report herein a review of the elevated risks of infection, malignancy, graft loss, cardiovascular events, and mortality in solid organ transplant populations.

Cardiovascular and Neurologic Complications in Kidney Transplant Recipients: A Focused Appraisal of Symptoms

BACKGROUND AND OBJECTIVE

After a kidney transplantation, all efforts are focused on graft function. However, cardiovascular and neurologic complications might lead to decreased quality of life and shortened life expectancy. Early recognition of related symptoms might be critical to successfully manage these complications.

METHODS AND PATIENTS

We retrospectively reviewed the medical records of patients who had undergone kidney transplantation in a tertiary center between January 2014 and December 2017. Demographic data and past medical history were systematically gathered. Symptoms related to cardiac or neurologic disorders and final diagnoses were recorded.

RESULTS

One hundred eighty-six patients were evaluated by a cardiologist or a neurologist in the early post-operative period or long-term follow-up. Chest pain (n = 17; 9.1%) and palpitations (n = 13; 7.0%) were the most prevalent symptoms. Coronary artery disease was diagnosed in 70.6% (n = 12) of the patients presenting with chest pain. All of the patients were treated successfully, with either antianginal drugs or percutaneous angioplasty. Atrial fibrillation was diagnosed in 53.9% (n = 7) of the patients presenting with palpitations. Headache was the most prevalent chronic neurologic symptom (n = 16; 8.6%). Transient ischemic attack occured in 7 patients (3.8%) and 5 (2.7%) patients experienced ischemic stroke.

CONCLUSION

Kidney transplantation is associated with short- and long-term cardiac and neurologic complications. Our findings underscore the crucial role of questioning symptoms that might be related to severe disorders. Asymptomatic patients with high risk factors must also be under scope. Attending physicians should have a low threshold for referring these patients to cardiologists and neurologists.

The Risk of Stroke in Kidney Transplant Recipients with End-Stage Kidney Disease

Background: The incidence of stroke after kidney transplantation is poorly understood. Our study aimed to determine the incidence and predictors of stroke as well as mortality from stroke in kidney transplant recipients (KTRs). Methods: This retrospective cohort study used the National Health Insurance Research Database in Taiwan to study KTRs (N = 4635), patients with end-stage renal disease (ESRD; N = 69,297), and patients from the general population who were chronic kidney disease (CKD)-free and matched by comorbidities (N = 69,297) for the years 2000 through 2010. The risk of stroke was analyzed using univariate and multivariate Cox regression models and compared between study cohorts. Findings: Compared with the ESRD subgroup, KTRs had a significantly lower risk of overall stroke (adjusted hazard ratio (aHR) = 0.37, 95% confidence interval (CI) = 0.31⁻0.44), ischemic stroke (aHR = 0.45, 95% CI = 0.37⁻0.55), and hemorrhagic stroke (aHR = 0.20, 95% CI = 0.14⁻0.29). The risk patterns for each type of stroke in the KTR group were not significantly different than those of the CKD-free control subgroup. The predictors of stroke were age and diabetes in KTRs. All forms of stroke after transplantation independently predicted an increased risk of subsequent mortality, and the strongest risk was related to hemorrhagic events. Interpretation: KTRs had a lower risk of stroke than ESRD patients, but this risk was not significantly different from that of the CKD-free comorbidities-matched general population group. Although stroke was relatively uncommon among cardiovascular events, it predicted unfavorable outcome in KTRs.

Fragmented QRS on 12-Lead Electrocardiogram Is Correlated With Severe Coronary Artery Disease and Abnormal Myocardial Perfusion Scintigraphy Results in Renal Transplant Candidates

OBJECTIVES

Coronary artery disease is a major cause of mortality and morbidity after renal transplant. Fragmented QRS on standard 12-lead electrocardiograms has been proposed as a marker of myocardial scar, mainly due to coronary artery disease. Here, we aimed to investigate fragmented QRS to detect severe coronary artery disease in renal transplant candidates.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 534 patients with end-stage renal failure who were on the deceased-donor renal transplant wait list at Başkent University Faculty of Medicine due to having no living kidney donor available. We evaluated patients with standard 12-lead electrocardiograms, myocardial perfusion scintigraphy, and coronary angiography. We compared fragmented QRS prevalence versus myocardial perfusion scintigraphy abnormalities and severe coronary artery disease. Correlations among these were analyzed.

RESULTS

Of 92 renal transplant candidates (median age of 56.5 y; range, 24-80 y), 87 patients (94.6%) had myocardial perfusion defects and 72 (78.3%) had myocardial wall motion abnormalities on myocardial perfusion scintigraphy. Forty-four patients (47.8%) had severe coronary artery disease on coronary angiography, and 51 patients (55.4%) had fragmented QRS. Fragmented QRS was significantly more common among patients with myocardial scar. Coronary artery disease was significantly more common in patients with fragmented QRS (P = .042) and in those with fragmented QRS combined with myocardial perfusion defects (P < .01). Fragmented QRS was significantly correlated with presence of myocardial scar and any perfusion defects. When combined with myocardial perfusion defects, fragmented QRS was significantly correlated with severe coronary artery disease (P < .05).

CONCLUSIONS

Fragmented QRS was significantly correlated with abnormal myocardial perfusion scintigraphy and severe coronary artery disease in renal transplant candidates. This simple parameter can provide valuable information on severe coronary artery disease and help to prevent excess patient morbidity and mortality from this disease after renal transplant.

Albuminuria and Allograft Failure, Cardiovascular Disease Events, and All-Cause Death in Stable Kidney Transplant Recipients: A Cohort Analysis of the FAVORIT Trial

RATIONALE & OBJECTIVE

Cardiovascular disease (CVD) is common and overall graft survival is suboptimal among kidney transplant recipients. Although albuminuria is a known risk factor for adverse outcomes among persons with native chronic kidney disease, the relationship of albuminuria with cardiovascular and kidney outcomes in transplant recipients is uncertain.

STUDY DESIGN

Post hoc longitudinal cohort analysis of the Folic Acid for Vascular Outcomes Reduction in Transplantation (FAVORIT) Trial.

SETTING & PARTICIPANTS

Stable kidney transplant recipients with elevated homocysteine levels from 30 sites in the United States, Canada, and Brazil.

PREDICTOR

Urine albumin-creatinine ratio (ACR) at randomization.

OUTCOMES

Allograft failure, CVD, and all-cause death.

ANALYTICAL APPROACH

Multivariable Cox models adjusted for age; sex; race; randomized treatment allocation; country; systolic and diastolic blood pressure; history of CVD, diabetes, and hypertension; smoking; cholesterol; body mass index; estimated glomerular filtration rate (eGFR); donor type; transplant vintage; medications; and immunosuppression.

RESULTS

Among 3,511 participants with complete data, median ACR was 24 (Q1-Q3, 9-98) mg/g, mean eGFR was 49±18 (standard deviation) mL/min/1.73m², mean age was 52±9 years, and median graft vintage was 4.1 (Q1-Q3, 1.7-7.4) years. There were 1,017 (29%) with ACR < 10mg/g, 912 (26%) with ACR of 10 to 29mg/g, 1,134 (32%) with ACR of 30 to 299mg/g, and 448 (13%) with ACR ≥ 300mg/g. During approximately 4 years, 282 allograft failure events, 497 CVD events, and 407 deaths occurred. Event rates were higher at both lower eGFRs and higher ACR. ACR of 30 to 299 and ≥300mg/g relative to ACR < 10mg/g were independently associated with graft failure (HRs of 3.40 [95% CI, 2.19-5.30] and 9.96 [95% CI, 6.35-15.62], respectively), CVD events (HRs of 1.25 [95% CI, 0.96-1.61] and 1.55 [95% CI, 1.13-2.11], respectively), and all-cause death (HRs of 1.65 [95% CI, 1.23-2.21] and 2.07 [95% CI, 1.46-2.94], respectively).

LIMITATIONS

No data for rejection; single ACR assessment.

CONCLUSIONS

In a large population of stable kidney transplant recipients, elevated baseline ACR is independently associated with allograft failure, CVD, and death. Future studies are needed to evaluate whether reducing albuminuria improves these outcomes.

Smoking and outcomes in kidney transplant recipients: a post hoc survival analysis of the FAVORIT trial

Background

Tobacco use remains an international health problem with between 10% and 40% of adults currently using tobacco. Given the rising number of patients either awaiting or having received a kidney transplant and the absence of smoking cessation as the criterion for transplantation in guidelines, we explored the association between smoking status and clinical outcomes in kidney transplant recipients.

Patients and methods

In this post hoc analysis of the Folic Acid for Vascular Outcome Reduction in Transplant trial, the associations between smoking status, defined as never having smoked, formerly or currently smoking, and both all-cause mortality and graft survival were assessed using Cox proportional hazards models. Fatal events were centrally adjudicated into prespecified categories: all-cause, cardiovascular and non-cardiovascular causes. Graft loss was defined as return to dialysis or retransplantation. Clinical Trials URL: http://www.clinicaltrials.gov/show/NCT00064753.

Results

Among 4110 transplant recipients, there were 451 current smokers and 1611 former smokers. The mortality rate per 100 patient-years was 4.0 (71 deaths) for smokers, 3.5 (226 deaths) for former smokers and 2.4 (116 deaths) for never smokers. Hazard ratio for mortality for current smokers was 1.70 (CI=1.26–2.29, p=0.001) and for former smokers was 1.21 (0.98–1.50, p=0.08) with 1.0 representing never smokers. As the number of cardiovascular deaths was similar in each group (all p>0.3), the differences between groups was driven by non-cardiovascular death rates. Current smokers (2.39; 1.62–3.61, p<0.001) and former smokers (1.50; 1.12–2.01, p=0.007) had increased hazard of non-cardiovascular death. Kidney allograft failure was more likely in current smokers than in either former or never smokers (3.5, 2.1 and 2.0 per 100 patient-years, p<0.001, adjusted hazard ratio 1.49 and 1.05, respectively).

Conclusion

Continued smoking was associated with >100% increased risk of non-cardiovascular death, 70% greater risk of all-cause mortality and a 50% greater risk of graft loss, a risk not seen in former smokers. These findings confirm previous non-adjudicated observations that smoking is associated with adverse clinical outcomes and suggest that more emphasis should be placed on smoking cessation prior to kidney transplantation.

Obesity and the risk of cardiovascular and all-cause mortality in chronic kidney disease: a systematic review and meta-analysis

Background

Obesity is a risk factor for cardiovascular disease and death in people without chronic kidney disease (CKD), but the effect of obesity in people with CKD is uncertain.

Methods

Medline and Embase (from inception to January 2015) were searched for cohort studies measuring obesity by body mass index (BMI), waist:hip ratio (WHR) and/or waist circumference (WC) and all-cause and cardiovascular mortality or events in patients with any stage of CKD. Data were summarized using random effects models. Meta-regression was conducted to assess sources of heterogeneity.

Results

Of 4065 potentially eligible citations, 165 studies ( n = 1 534 845 participants) were analyzed. In studies that found a nonlinear relationship, underweight people with CKD (3-5) on hemodialysis experienced an increased risk of death compared with those with normal weight. In transplant recipients, excess risk was observed at levels of morbid obesity (>35 kg/m 2 ). Of studies that found the relationship to be linear, a 1 kg/m 2 increase in BMI was associated with a 3 and 4% reduction in all-cause and cardiovascular mortality in patients on hemodialysis, respectively {adjusted hazard ratio [HR] 0.97 [95% confidence interval (CI) 0.96-0.98] and adjusted HR 0.96 (95% CI 0.92-1.00)}. In CKD Stages 3-5, for every 1 kg/m 2 increase in BMI there was a 1% reduction in all-cause mortality [HR 0.99 (95% CI 0.0.97-1.00)]. There was no apparent association between obesity and mortality in transplanted patients or those on peritoneal dialysis. Sparse data for WHR and WC did not allow further analyses.

Conclusions

Being obese may be protective for all-cause mortality in the predialysis and hemodialysis populations, while being underweight suggests increased risk, but not in transplant recipients.

Preoperative Cardiac Risk Assessment in Renal Transplant Recipients: A Single-Center Experience

OBJECTIVES

Cardiovascular disease is the major cause of morbidity and mortality in patients on renal replacement therapy and in kidney transplant recipients. There are no specific recommendations for preoperative cardiac risk assessment before renal transplant. The aim of our study was to analyze preoperative cardiac test frequencies, test results, patient characteristics, and relations between cardiac stress test results and severe coronary artery disease.

MATERIALS AND METHODS

We retrospectively examined patients who underwent renal transplant between December 2011 and December 2016 in our hospital (Ankara, Turkey). Our study group included 216 patients. All patients had preoperative echocardiography. We recorded results of exercise stress tests, myocardial perfusion scintigraphy, and coronary angiography. For all patients, preoperative complete blood cell count, creatinine, high-density lipoprotein, triglycerides, low-density lipoprotein, and red cell distribution width values were obtained and recorded.

RESULTS

We classified patient groups according to presence or absence of severe coronary artery disease. Fourteen of 66 patients had severe coronary artery disease. In univariate analyses, age, having a history of familial coronary artery disease, diabetes mellitus, presence of coronary artery disease, and triglyceride levels were risk factors for severe coronary artery disease. In multivariate analysis, diabetes mellitus, presence of coronary artery disease, and having a history of familial coronary artery disease were statistically significant.

CONCLUSIONS

Renal transplant recipients are a special patient population, and there must be specific suggestions for this population. If patients present with more than 1 risk factor, a stress test should be performed to evaluate cardiovascular risk. In some patients, especially those whose risk factors include prior cardiovascular disease or diabetes mellitus, stress tests should be skipped and patients should directly undergo coronary angiography to look for severe coronary artery disease.

Study of Cardiovascular Outcomes in Renal Transplantation: A Prospective, Multicenter Study to Determine the Incidence of Cardiovascular Events in Renal Transplant Recipients in Ontario, Canada

Background:

Renal transplant recipients (RTRs) are at significantly higher risk for morbidity and mortality compared with the general population, largely attributed to cardiovascular disease (CVD). Previous estimates of CVD events have come from health care databases and retrospective studies.

Objective:

The objective of this study was to prospectively determine the prevalence of risk factors and incidence of CVD events in a Canadian cohort of RTRs.

Design:

Study of Cardiovascular Outcomes in Renal Transplantation (SCORe) was a prospective, longitudinal, multicenter observational study.

Setting:

Adult RTRs were recruited from 6 participating transplant sites in Ontario, Canada.

Patients:

Eligible patients were those receiving a living or deceased donor renal transplant. Patients who received simultaneous transplant of any other organ were excluded.

Measurements:

Primary outcomes included myocardial infarction (MI) defined by American College of Cardiology (ACC-MI) criteria, and major adverse cardiac events (MACE), defined as cardiovascular (CV) death, ACC-MI, coronary revascularization, and nonhemorrhagic stroke. CV events were adjudicated by a single, independent cardiologist.

Methods:

CV and transplant-specific risk factors that predict MACE and ACC-MI were identified by stepwise regression analysis using the Cox proportional hazards model.

Results:

A total of 1303 patients enrolled across 6 transplant centers were followed for 4.5 ± 1.6 years (mean ± SD). Incidence of MACE was 7.0%, with significant independent predictors/risk factors including age, diabetes, coronary revascularization, nonhemorrhagic stroke, and renal replacement therapy (RRT). ACC-MI incidence was 4.0%, with significant independent predictors/risk factors including age, coronary revascularization, and duration of RRT in excess of the median value (2.91 years).

Limitations:

Patients were recruited from a single province, so may not reflect the experience of RTRs in other areas of Canada.

Conclusions:

Using a prospective design and rigorous methodology, this study found that the incidence of CV events after renal transplantation was elevated relative to the general Canadian population and was comparable with that reported in patient registries, thus helping validate the utility of retrospective analysis in this field. SCORe highlights the importance of monitoring RTRs for traditional cardiac and transplant-specific CV risk factors to help prevent CV morbidity and mortality. Further research is needed to investigate a broader range of potential risk factors and their combined effects on incident CV events.

[Post-transplantation diabetes mellitus in kidney recipients]

Post-transplantation diabetes mellitus is defined as diabetes that is diagnosed in grafted patients. It affects 20 to 30 % of kidney transplant recipients, with a high incidence in the first year. The increasing age at transplantation and the rising incidence of obesity may increase its prevalence in the next years. Post-transplantation diabetes mellitus is associated with poor outcomes, such as mortality, cardiovascular events or graft dysfunction. Its occurrence is mainly related to immunosuppressive agents, affecting both insulin secretion and sensibility. Immunosuppressants may be iatrogenic, and as such, induce an early and transient diabetes. They may also precociously determine a permanent diabetes, acting here as a promoting factor in patients proned to the development of type 2 diabetes. Lastly, they may behave, far from transplantation, as an additional risk factor for type 2 diabetes. The screening, management and prognosis of these different subtypes of post-transplantation diabetes mellitus will be different.

Stroke in Patients with Chronic Kidney Disease…: How do we Approach and Manage it?

Renal failure is a potent risk factor for stroke, which is a leading cause of morbidity and mortality worldwide. The risk of stroke is 5–30 times higher in patients with chronic kidney disease (CKD), especially on dialysis. Case fatality rates are also higher reaching almost 90%. It is therefore important to understand the factors that predispose to stroke in this vulnerable population to better apply preventive strategies. The heightened risk of stroke in CKD represents the interplay of the vascular co-morbidities that occur with renal impairment and factors specific to renal failure such as malnutrition-inflammation-atherosclerosis complex, the effect of uremic toxins, dialysis techniques, vascular access, and the use of anticoagulants to maintain flow in the extracorporeal circuit. Old age, hypertension, diabetes, and previous cerebrovascular disease are all risk factors for stroke with the period of dialysis initiation constituting the highest risk period for developing new stroke. Patients with CKD-stage 3–5 have worse survival and diminished functional outcomes following stroke. Thrombolytic therapy for stroke in CKD has shown an increased risk of symptomatic intracranial hemorrhage or serious systemic hemorrhage, and the therapeutic effects may be attenuated. Benefit of statin therapy in dialysis patient as preventive therapy has not been shown to be beneficial. Control of hypertension and the judicious use of antiplatelet agents form the mainstay of stroke prevention. The benefit of antiplatelet therapies and oral anticoagulants has to be balanced against the real and increased risk of bleeding that is most evident in dialysis cohorts. An increased risk of vascular calcification particularly intracerebral vascular calcification has been seen in patientsreceiving warfarin as prophylaxis in atrial fibrillation. Newer anticoagulants have not been tested in patients with glomerular filtration rate <30 ml/min and hence have to be used with caution. This article is a review of stroke in patients with CKD and approach to managing it.

Cardiovascular Risk Evaluated With the Use of Heartscore in Kidney Transplant Recipients-Three Years of Follow-up

BACKGROUND

Cardiovascular (CV) complications are the major cause of death in kidney transplant (KT) patients.

METHODS

During a 3-year follow-up, 112 KT recipients, from living (LD KTRs; n = 54), and deceased (DD KTRs; n = 58) donors, were assessed for 10-year risk of fatal CV events with the use of the Heartscore tool (www.heartscore.org). In post-KT months 6, 12, and 36, current and optimum (target) CV risks (CVRs) were estimated.

RESULTS

Current risk was lower in the LD KTRs and remained stable. In DD KTRs, the risk was at the highest level in months 6 and 12 of follow-up and decreased in month 36. Change in CVR, ie, the difference between the current and target risk, was the highest in DD KTRs in month 36 of follow-up (P = .014). In the increased-CVR group, recipients were older (P < .01), primarily male (P = .08), and more frequently smokers (P < .01) and had a higher systolic blood pressure (P < .05) despite taking more hypotensive medicines (P < .01), and had higher total cholesterol (P < .01) and low-density lipoprotein (P < .01) levels. In this group, body mass index (BMI) was higher (P < .01) and metabolic syndrome was diagnosed significantly more often (P < .01). The high-risk group (estimated CVR, ≥5) was different also in longer durations of pre-transplantation dialysis (P < .05) and higher rates of CV episodes before transplantation (P < .05). In logistic regression, higher BMI and lower estimated glomerular filtration rate (eGFR) were the parameters strongly correlated with higher CVR.

CONCLUSIONS

Mean CVR applicable to all kidney transplant recipients was stable throughout the follow-up. Changes in the risk affected mainly DD KTRs. In months 6 and 12, CVR was the highest in this group and was substantially reduced in the 3rd year of follow-up, probably owing to medical interventions. In the high-CVR group, impaired function of the transplanted kidney was recorded. CVR scores in patients with renal conditions and after kidney transplantation should additionally account for eGFR.

Pre-Transplant Cardiovascular Risk Factors Affect Kidney Allograft Survival: A Multi-Center Study in Korea

Background

Pre-transplant cardiovascular (CV) risk factors affect the development of CV events even after successful kidney transplantation (KT). However, the impact of pre-transplant CV risk factors on allograft failure (GF) has not been reported.

Methods and Findings

We analyzed the graft outcomes of 2,902 KT recipients who were enrolled in a multi-center cohort from 1997 to 2012. We calculated the pre-transplant CV risk scores based on the Framingham risk model using age, gender, total cholesterol level, smoking status, and history of hypertension. Vascular disease (a composite of ischemic heart disease, peripheral vascular disease, and cerebrovascular disease) was noted in 6.5% of the patients. During the median follow-up of 6.4 years, 286 (9.9%) patients had developed GF. In the multivariable-adjusted Cox proportional hazard model, pre-transplant vascular disease was associated with an increased risk of GF (HR 2.51; 95% CI 1.66–3.80). The HR for GF (comparing the highest with the lowest tertile regarding the pre-transplant CV risk scores) was 1.65 (95% CI 1.22–2.23). In the competing risk model, both pre-transplant vascular disease and CV risk score were independent risk factors for GF. Moreover, the addition of the CV risk score, the pre-transplant vascular disease, or both had a better predictability for GF compared to the traditional GF risk factors.

Conclusions

In conclusion, both vascular disease and pre-transplant CV risk score were independently associated with GF in this multi-center study. Pre-transplant CV risk assessments could be useful in predicting GF in KT recipients.

Managing Cardiovascular Risk in the Post Solid Organ Transplant Recipient

Solid organ transplantation is an effective treatment for patients with end-stage organ disease. The prevalence of cardiovascular diseases (CVD) has increased in recipients. CVD remains a leading cause of mortality among recipients with functioning grafts. The pathophysiology of CVD recipients is a complex interplay between preexisting risk factors, metabolic sequelae of immunosuppressive agents, infection, and rejection. Risk modification must be weighed against the risk of mortality owing to rejection or infection. Aggressive risk stratification and modification before and after transplantation and tailoring immunosuppressive regimens are essential to prevent complications and improve short-term and long-term mortality and graft survival.

Paediatric obesity and renal transplantation: current challenges and solutions

The increased incidence of obesity in the paediatric population poses significant challenges to renal transplantation. Whilst the body mass index appears to be widely used as a measure of obesity in adults, there are no standardised definitions in the paediatric population, making comparative analyses difficult. In the paediatric transplant population, obesity is associated with an increased incidence of surgical complications, diabetes, hyperlipidaemia and cardiovascular morbidity, leading to diminished graft function and impacting patient and graft survival. Management of obesity in renal transplantation requires multiple interventions starting with life-style and behavioural modification combined with medical and possibly surgical therapies, representing a unique challenge in the childhood setting. In this review we discuss the current challenges of obesity and potential solutions in the setting of paediatric transplantation.

Hyperviscosity in renal transplant recipients

OBJECTIVE

The resistance of blood to flow is called plasma viscosity. Increased blood viscosity has been described in patients with coronary and peripheral arterial disease. In this study, we evaluated the influence of clinical and laboratory findings on plasma viscosity in renal transplant recipients.

METHODS

Eighty-one kidney transplant recipients (37.8 ± 11.3 years old, 50.38 ± 16.8 months post-transplantation period, 27 female) with normal graft functions were enrolled. The biochemical and clinical parameters in the 1st year after transplantation were retrospectively recorded, and graft function was evaluated by means of the yearly decline in eGFR. Plasma viscosity was measured and searched for the association with cross-sectionally analyzed cardiovascular parameters including body composition analyses, ambulatory blood pressure monitoring (ABPM) data, and pulse-wave velocity.

RESULTS

Patients were divided into 2 groups according to the median value of serum viscosity. Patients with high viscosity had higher serum low-density lipoprotein (P = .042) and C-reactive protein (P = .046) levels than lower viscosity group. In ABPM, daytime (P = .047) and office systolic (P = .046) blood pressure levels and left ventricular mass index (LVMI; P = .012) were significantly higher in patients with hyperviscosity. Patients with high viscosity had higher hip circumference (P = .038) and fat mass (P = .048). Estimated glomerular filtration rate decline was significantly higher in high-viscosity patients than in patients with low viscosity levels (12.9% vs 17.2%; P = .001) at 2 years' follow-up.

CONCLUSIONS

We suggest that the hyperviscous state of the renal transplant recipients may arise from the inflammatory state, hypertension, and increased fat mass and increased LVMI. Hyperviscosity is also closely related to renal allograft dysfunction.

Valve-sparing aortic root reconstruction in patient with prior renal transplantation

We describe a David operation in a 62-year-old renal transplant recipient with valsalva aneurysm and concomitant aortic insufficiency. The risk of postoperative infection seemed significant because he was receiving immunosuppressive therapy; thus, David operation was performed. He recovered uneventfully. David operation appears to be an attractive alternative in transplant recipients.