Cardiac and Noncardiac Determinants of Exercise Capacity in CKD

Open in a separate window     

Assessed value of high-sensitivity cardiac troponin T for cardiovascular disease among CKD patients

Objective To analyze the relationship between serum high-sensitivity cardiac troponin T (hs-cTnT) and cardiovascular disease (CVD) among non-dialysis chronic kidney disease (CKD) patients, and to further explore its value of evaluating and predicting CVD in this population. Methods Five hundred and fifty-seven non-dialysis CKD patients were involved in this cross-sectional study. The relationship between serum hs-cTnT and CVD was analyzed using comparison between groups and regression analysis, and its value on assessing cardiac structure and function was evaluated by ROC curves. Results Median level of hs-cTnT was 13 (7–29) ng/L, with 1.7% undetectable, 46.4% greater than 99th percentile of the general population. Multivariate analysis suggested that compared with the lowest quartile of hs-cTnT, the highest quartile was approximately six times as likely to develop into LVH (OR, 6.515; 95% CI, 3.478–12.206, p?<?0.05) and 18 times as likely to progress to left ventricular diastolic dysfunction(OR, 18.741; 95% CI, 2.422–145.017, p?<?0.05). And Ln cTnT level had a more modest association with LVEF (OR, ?1.117; 95% CI, ?5.839 to ?0.594; p?<?0.05). When evaluated as a screening test, the area under the curve of ROC curves for hs-cTnT was 0.718, 0.788 and 0.736, respectively (p?<?0.05). With a specificity of 90% as a diagnostic criterion, the value of hs-cTnT to evaluate LVH, LVEF?Conclusions In CKD non-dialysis population, hs-cTnT and NT-proBNP were valuable for evaluating LVH, left ventricular systolic dysfunction and left ventricular diastolic dysfunction.     

Cardiac Valve Calcifications and Left Ventricular Hypertrophy in Hemodialysis Patients

Cardiac valve calcification (VC) is a common finding in end-stage renal disease patients. It was shown recently that VC is an independent predictor for all-cause and cardiovascular mortality in peritoneal dialysis patients. In hemodialysis (HD) patients, VC was associated with all-cause and cardiovascular mortality, but after adjusting for other cardiovascular risk factors and complications, as well as left ventricular mass index (LVMI), it lost significance. The aim of the study was to assess the relationship between VC and left ventricular hypertrophy in hemodialysis patients. Echocardiographic examination with mitral and aortic valves assessment and LVMI calculation was performed in 65 HD patients ages 49 ± 12, with duration of HD therapy 38 ± 32 months. VC were found in 32 of 65 patients (49%)—Group VC(+), mitral valve calcifications (MVC) in 10, aortic valve calcifications (AVC) in 9, and both valves calcifications (MVC + AVC) in 13 patients. Patients with VC were older, on HD therapy were longer, had higher systolic and pulse pressure, and had higher LVMI. Patients with both VCs had the highest LVMI. No significant differences were found with respect to Ca, P, PTH, and mean Ca × P product, but the incidence of Ca × P product above 4.43 mmol²/L² was higher in VC(+) compared with those without VCs. VC coexists with left ventricular hypertrophy, particularly when both valves are calcified. Even short-lasting incidents of increased Ca × P product may lead to cardiac VC.     

Time-dependent changes in cardiac growth after kidney transplantation: the impact of pre-dialysis ventricular mass.

BACKGROUND: Left ventricular hypertrophy (LVH) is common in chronic kidney disease (CKD), including kidney transplant recipients. However, time-related left ventricular mass changes (DeltaLVM) from pre-dialysis stage to beyond the first post-transplant year have not been clearly identified. METHODS: We studied a cohort of 60 stages 4-5 CKD patients without overt cardiac disease, who underwent three echocardiograms during follow-up: at pre-dialysis stage, on dialysis and after kidney transplantation (KT). Multiple linear regression was used to model DeltaLVM from baseline study. Cox proportional analysis was used to determine risk factors associated with either de novo LVH or>20% DeltaLVMI over time. RESULTS: Patients with baseline LVH (n=37; 61%) had a higher body mass index (BMI) than those without LVH (n=23; 39%) (P=0.013). BMI, haemoglobin levels (P=0.047) and non-use of angiotensin-converting enzyme inhibitors (ACEI) (P=0.057) were associated with baseline left ventricular mass index (LVMI). Twelve out of 23 patients (52%) with normal LVM at baseline, developed either de novo LVH or>20% DeltaLVMI at follow-up. On the other hand, 29 (78%) of those with initial LVH maintained this abnormality, and 8 (22%) normalized LVM post-transplantation. Factors associated with DeltaLVMI were age (P=0.01), pre-dialysis LVMI (P<0.0001), serum creatinine (P=0.012) and the use of ACEI post-transplantation (P=0.009). In Cox analysis, pre-dialysis LVMI was associated with de novo LVH or>20% DeltaLVMI over time (hazard ratio 1.009; 95% confidence interval 1.004 to 1.015; P=0.001). CONCLUSIONS: Successful KT may not completely normalize LVM post-transplantation. Pre-dialysis LVMI, traditional risk factors and no use of ACEI may perpetuate cardiac growth following KT.     

Left ventricular mass in hypertensive patients with mild‐to‐moderate reduction of renal function

Aim: Left ventricular hypertrophy (LVH) is an independent predictor of cardiovascular (CV) morbidity and mortality. The aim of the present study was to evaluate the relationship between LV mass and mild‐to‐moderate renal dysfunction in a group of non‐diabetic hypertensives, free of CV diseases, participating in the Renal Dysfunction in Hypertension (REDHY) study. Methods: Patients with diabetes, a body mass index (BMI) of more than 35 kg/m², secondary hypertension, CV diseases and a glomerular filtration rate (GFR) of less than 30 mL/min per 1.73 m² were excluded. The final sample included 455 patients, who underwent echocardiographic examination and ambulatory blood pressure monitoring. Results: There was a significant trend for a stepwise increase in LV mass, indexed by both body surface area (LVMI) and height elevated to 2.7 (LVMH^2.7), with the declining renal function, that remained statistically significant after correction for potential confounders. The prevalence of LVH, defined either as LVMI of 125 g/m² or more or as LVMH^2.7 of 51 g/m^2.7 or more, was higher in subjects with lower values of GFR than in those with normal renal function (P < 0.001 in both cases). The multiple regression analysis confirmed that the inverse association between GFR and LVM was independent of confounding factors. Conclusion: The present study confirms the high prevalence of LVH in patients with mild or moderate renal dysfunction. In the patients studied (all with a GFR of 30 mL/min per 1.73 m²), the association between LVM and GFR was independent of potential confounders, including 24 h blood pressure load. Taking into account the negative prognostic impact of LVH, further studies focusing on a deeper comprehension of the mechanisms underlying the development of LVH in chronic kidney disease patients are needed.     

Optimal care of autosomal dominant polycystic kidney disease patients

Autosomal dominant polycystic kidney disease (ADPKD) is the most common life-threatening, hereditary disease. The prevalence of ADPKD is more common than Huntington disease, haemophilia, sickle cell disease, cystic fibrosis, myotonic dystrophy and Down syndrome combined. In recent years there have not only been advances in the understanding of the genetic and molecular events involved in ADPKD, but some diagnostic and therapeutic advances have also emerged. In the genetics area, the gene for PKD1 was localised to chromosome 16, is associated with polycystin-2 protein, and found to account for approximately 85% of patients with ADPKD. The gene for PKD2, found in chromosome 4, accounts for approximately 15% of ADPKD, and is associated with the polycystin-2 protein. While these genetic and molecular biology findings have stimulated a great deal of exciting basic research in ADPKD, therapies to decrease morbidity and mortality in ADPKD patients have yet to emerge from these findings. In contrast, the early diagnosis and treatment of hypertension with inhibitors of the renin-angiotensin-aldosterone system have the potential to decrease or prevent left ventricular hypertrophy cardiac complications and slow the progression of the renal disease.     

The Relationship between Cardiac Troponins and Left Ventricular Mass Index in Patients with Chronic Renal Failure

The abstract of this study was accepted as an oral presentation in the 10^th Annual Meeting of the ESC Working Group on Echocardiography, December 6–9, 2006, Prague, Czech Republic     

Cardiac impact of the arteriovenous fistula after kidney transplantation: a case‐controlled,match‐paired study

In kidney transplant (KT) recipients, cardiac impact of the persistence of an asymptomatic arteriovenous fistula (AVF) for hemodialysis has not been fully elucidated. Seventy‐six patients (mean age: 49 years) without history of diabetes or cardiovascular disease underwent an echocardiography. Thirty‐eight had a functioning AVF and were match‐paired for age, gender and KT duration. Left ventricular mass index (LVMI) was significantly higher in patients with functioning AVF: 135.1 ± 30.3 vs. 112.4 ± 28 g/m² (P = 0.001). Exposure to AVF increased the risk of developing high LVH fourfold. Search for a dose‐effect of AVF flow revealed a trend towards increasing LVMI with higher flow: 142.6 ± 30 vs. 126.9 ± 23.9 g/m² (P = 0.084) (median flow of the population as cut‐off). Other significant changes were observed in left ventricular dimensions: greater end diastole‐ and systole diameters, both larger left and right atria, and left atrium diameter. Our study suggests that, in stable asymptomatic KT patients, functioning AVF has significant impact on cardiac mass, cardiac index and left ventricular dimensions. The effects on morbidity and mortality were to be investigated.     

慢性肾脏疾病患者左室结构及功能改变的超声评价

目的：应用超声心动图评价慢性肾脏疾病（CKD）患者左室结构及功能改变,探讨不同程度CKD患者左室改变情况。方法：对CKD非透析患者39例（CKD2～3期组19例,CKD4～5期组20例）及对照组40例进行常规肾脏扫查及超声心动图检查,通过二维超声观察CKD患者肾脏形态结构、实质回声、皮髓质分界、血流信号改变;通过超声心动图获得左室结构参数：左房内径（LAD）、左室舒张末期内径（I。VID）,左室质量指数（LV—MI）、左室相对室壁厚度（RWT）;左室功能参数：左室射血分数（EF）、二尖瓣口舒张早期血流速度E峰、晚期A峰、E／A、舒张早期二尖瓣环运动速度Em,E／Era。结果：①CKD2～3期组19例患者中6例患者肾脏声像图有明显改变,CKD4～5期组中18例患者肾脏声像图有显著改变;②与正常组比较,cKD2～3期组LVM、RWT、LAD均显著增高,CKD4～5期组LVID、LVMI、E、A、E／Em增高,DTE、E／A、Em减低,与CKD2～3期组比较,CKD4～5期组LVM、RWT、LAD、LVID、LVMI、E、A、EjEm显著增加,DTE显著减低,E／A、Em无明显差异;③CKD2～3期组中有5例左室重构（26．3％）,CKD4～5期组患者中有17例左室壁重构（85％）。结论：早中期CKD患者其肾脏结构二维超声改变不明显,而超声心动图能早期检测到CKD患者左室构型及左室舒张功的改变,为临床上该病治疗及心血管并发症的预防提供有价值的参考信息。     

High-Sensitivity Troponin T and N-Terminal Pro-B-Type Natriuretic Peptide (NT-proBNP) and Risk of Incident Heart Failure in Patients with CKD: The Chronic Renal Insufficiency Cohort (CRIC) Study

High-sensitivity troponin T (hsTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) strongly predict heart failure (HF) in the general population. However, the interpretation of levels of these biomarkers as predictors of HF is uncertain among patients with CKD. Here, we investigated whether hsTnT and NT-proBNP are associated with incident HF among patients with CKD. In a prospective cohort analysis, we studied 3483 people with CKD in the Chronic Renal Insufficiency Cohort (CRIC) Study recruited from June of 2003 to August of 2008 who were free of HF at baseline. We used Cox regression to examine the association of baseline levels of hsTnT and NT-proBNP with incident HF after adjustment for demographic factors, traditional cardiovascular risk factors, markers of kidney disease, pertinent medication use, and mineral metabolism markers. At baseline, hsTnT levels ranged from ≤5.0 to 378.7 pg/ml, and NT-proBNP levels ranged from ≤5 to 35,000 pg/ml. Compared with those who had undetectable hsTnT, participants in the highest quartile (>26.5 ng/ml) had a significantly higher rate of HF (hazard ratio, 4.77; 95% confidence interval, 2.49 to 9.14). Similarly, compared with those in the lowest NT-proBNP quintile (<47.6 ng/ml), participants in the highest quintile (>433.0 ng/ml) experienced a substantially higher rate of HF (hazard ratio, 9.57; 95% confidence interval, 4.40 to 20.83). In conclusion, hsTnT and NT-proBNP were strongly associated with incident HF among a diverse cohort of individuals with mild to severe CKD. Elevations in these biomarkers may indicate subclinical changes in volume and myocardial stress that subsequently contribute to clinical HF.     

Platelet Function in CKD: A Systematic Review and Meta-Analysis

Open in a separate window     

BP in Young Adults with CKD and Associations with Cardiovascular Events and Decline in Kidney Function

Open in a separate window     

Slope of Kidney Function and Its Association with Longitudinal Mortality and Cardiovascular Disease among Individuals with CKD

Open in a separate window     

Cardiac output and associated left ventricular hypertrophy in pediatric chronic kidney disease

A significant number of children with chronic kidney disease (CKD) have eccentric left ventricular hypertrophy (LVH), suggesting the role of preload overload. Therefore, we hypothesized that increased cardiac output (CO) might be a contributing factor for increased left ventricular mass index (LVMI) in these children. Patients aged 6–20 years with CKD stages 2–4 were enrolled. Echocardiograms were performed to assess LV function and geometry at rest and during exercise. Heart rate, stroke volume, and CO were also assessed at rest and during exercise. Twenty-four-hour ambulatory blood pressure (AMBP) monitoring was performed. Of the patients enrolled in this study, 17% had LVH. Increased stroke volume and CO were observed in patients with LVH compared to patients without LVH. Univariate analysis revealed significant positive associations between LVMI and CO, stroke volume, body mass index, pulse pressure from mean 24-h AMBP, and mean 24-h systolic BP load. No association with heart rate, age, parathyroid hormone, glomerular filtration rate, or anemia was observed. Only CO (β = 1.98, p = 0.0005) was independently associated with increased LVMI in multivariate modeling (model R ² = 0.25). The results of this study suggest that increased CO might predispose to increased LVMI in pediatric patients with CKD. Adaptations may be required to meet increased metabolic demand in these patients.