Association of renal biochemical parameters with left ventricular diastolic dysfunction in a community-based elderly population in China: a cross-sectional study

Renal Insufficiency Increases the Combined Risk of Left Ventricular Hypertrophy and Dysfunction in Patients at High Risk of Cardiovascular Diseases

BACKGROUND

The identification of asymptomatic structural and functional cardiac abnormalities can help us to recognize early and intervene in patients at pre-heart failure (HF). However, few studies have adequately evaluated the associations of renal function and left ventricular (LV) structure and function in patients at high risk of cardiovascular diseases (CVD).

METHODS

Patients undergoing coronary angiography and/or percutaneous coronary interventions were enrolled from the Cardiorenal ImprovemeNt II (CIN-II) cohort study, and their echocardiography and renal function were assessed at admission. Patients were divided into five groups according to their estimated glomerular filtration rate (eGFR). Our outcomes were LV hypertrophy and LV systolic and diastolic dysfunction. Multivariable logistic regression analyses were conducted to investigate the associations of eGFR with LV hypertrophy and LV systolic and diastolic dysfunction.

RESULTS

A total of 5610 patients (mean age: 61.6 ± 10.6 years; 27.3% female) were included in the final analysis. The prevalence of LV hypertrophy assessed by echocardiography was 29.0%, 34.8%, 51.9%, 66.7%, and 74.3% for the eGFR categories >90, 61-90, 31-60, 16-30, and ≤15 mL/min per 1.73 m² or for patients needing dialysis, respectively. Multivariate logistic regression analysis showed that subjects with eGFR levels of ≤15 mL/min per 1.73 m2 or needing dialysis (OR: 4.66, 95% CI: 2.96-7.54), as well as those with eGFR levels of 16-30 (OR: 3.87, 95% CI: 2.43-6.24), 31-60 (OR: 2.00, 95% CI: 1.64-2.45), and 61-90 (OR: 1.23, 95% CI: 1.07-1.42), were significantly associated with LV hypertrophy. This reduction in renal function was also significantly associated with LV systolic and diastolic dysfunction (all P for trend <0.001). In addition, a per one unit decrease in eGFR was associated with a 2% heightened combined risk of LV hypertrophy and systolic and diastolic dysfunction.

CONCLUSIONS

Among patients at high risk of CVD, poor renal function was strongly associated with cardiac structural and functional abnormalities. In addition, the presence or absence of CAD did not change the associations. The results may have implications for the pathophysiology behind cardiorenal syndrome.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Fibrosis, the Bad Actor in Cardiorenal Syndromes: Mechanisms Involved

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

Blood urea nitrogen is associated with long-term all-cause mortality in stable angina pectoris patients: 8-year follow-up results

Background    Elevation of blood urea nitrogen (BUN) indicates renal dysfunction and is associated with increased mortality in cardiovascular diseases. We investigated the relationship between the BUN concentration measured at hospital admission and the long-term all-cause mortality in patients with stable angina pectoris (SAP).Methods    The mortality rate of 344 patients who underwent coronary angiography (CAG) in our clinic due to SAP was analyzed during a mean follow-up period of 8 yrs.Results    Age (p&lt;0.001), male gender (p=0.020), waist circumference (p=0.007), body-mass index (p=0.002), fasting glucose (p=0.004), BUN (p&lt;0.001), serum creatinine (Cr) (p&lt;0.001), hemoglobin (p=0.015), triglyceride concentrations (p=0.033), and the Gensini score (p&lt;0.001) were related to all-cause mortality as shown by univariate Cox regression analysis. Age (OR 1.056, 95 % CI 1.015-1.100, p=0.008), fasting glucose (OR 1.006, 95 % CI 1.001-1.011, p=0.018), BUN, (OR 1.077, 95 % CI 1.026-1.130, p=0.003), and the Gensini score (OR 2.269, 95 % CI 1.233-4.174, p=0.008) were significantly related with mortality as shown by multivariate Cox regression analysis. According to receiver operating characteristic analysis ofthe sensitivity and specificity of BUN and Cr for predicting mortality, the area under the curve values of BUN and Cr were 0.789 (p&lt;0.001) and 0.652 (p=0.001), respectively. BUN had a stronger relationship with mortality than Cr. A concentration of BUN above 16.1 mg / dl had 90.1 % sensitivity and 60 % specificity for predicting mortality (OR=2.23).Conclusion    In patients who underwent CAG due to SAP, the BUN concentration was associated with all-cause mortality during a mean follow-up period of 8 yrs.

Preoperative blood urea nitrogen-to-left ventricular ejection fraction ratio is an independent predictor of long-term major adverse cardiac events in patients undergoing coronary artery bypass grafting surgery

BACKGROUND

Long-term mortality rate following coronary artery bypass grafting (CABG) procedure is still considered to be high despite advances in surgical techniques and perioperative management. Identifying high-risk patients by using cost-effective and clinically useful parameters is needed.

METHODS

Patients who were admitted to our cardiology clinic with the diagnosis of coronary artery disease and underwent CABG between January 2008 and August 2010 were included. Study patients were followed-up for 112.6 ± 17.8 months for major adverse cardiac events (MACE) which were defined as all-cause mortality and new-onset decompensated heart failure (HF).

RESULTS

Patients in MACE (+) group were older (p < 0.001), had higher additive Euroscore (p < 0.001), and lower left ventricular ejection fraction (p < 0.001). Multivariate Cox regression analysis showed that additive Euroscore [odds ratio (OR) = 1.601; 95% confidence interval (CI) = 1.374-1.864; p < 0.001)] and blood urea nitrogen-to-left ventricular ejection fraction ratio (BUNEFr; OR = 1.028; 95% CI = 1.006-1.050; p = 0.011) independently predicted MACE. Receiver operating characteristic curve analysis demonstrated that BUNEFr had an area under curve of 0.794 and BUNEFr >33 had a sensitivity and specificity of 74% and 64%, respectively.

CONCLUSION

BUNEFr is a clinically useful and cost-effective parameter for the prediction of long-term mortality and new-onset decompensated HF in patients undergoing CABG.

Vitamin D and cardiovascular disorders

Vitamin D is necessary for bone health but may also have many extra-skeletal effects. The vitamin D endocrine system has major effects on gene and protein expression in many cells and tissues related to the cardiovascular system. In addition, many preclinical studies in animals with vitamin D deficiency or genetically silenced expression of the vitamin D receptor or vitamin D metabolizing enzymes suggest that the absence of vitamin D action may result in cardiovascular events. This includes dysfunctions of endothelial cells, thereby accelerating the process of atherosclerosis, hypertension or abnormal coagulation, ultimately resulting in higher risks for all major cardiovascular or cerebrovascular events. A wealth of observational studies in different parts of the world have fairly consistently found a strong association between a poor vitamin D status and surrogate markers or hard cardiovascular events. A few Mendelian randomization studies did, however, not find a link between genetically lower serum 25OHD concentrations and cardiovascular events. Finally, many RCTs could not demonstrate a consistent effect on surrogate markers, and a limited number of RCTs did so far not find whatever effect on hard cardiovascular endpoints such as myocardial ischemia or infarction, stroke, or cardiovascular death. In conclusion, preclinical data generated a plausible hypothesis of a link between vitamin D status and extra-skeletal events, including cardiovascular endpoints. Whether the vitamin D endocrine system is redundant for the human vascular system or whether the RCTs have not been optimally designed to answer the research question is thus not yet settled.

Ultrasonic evaluation of renal cortex arterial area enables differentiation between hypertensive and glomerulonephritis-related chronic kidney disease

PURPOSE

Identifying the primary etiology of cardio-renal syndrome in a timely manner remains an ongoing challenge in nephrology. We hypothesized that hypertensive kidney damage can be distinguished from chronic glomerulonephritis at an early stage of chronic kidney disease (CKD) using ultrasound (US) Doppler sonography.

METHODS

Fifty-six males (age 54 ± 15, BMI 28.3 ± 3.5 kg/m2) with hypertension and stable CKD at stages 2-4 [38 with essential hypertension (HT-CKD); 18 with glomerulonephritis (GN-CKD)] were studied. Blood tests, UACR, echocardiography, ABPM, carotid IMT, and an ultrasound dynamic tissue perfusion measurement (DTPM) of the renal cortex were performed.

RESULTS

HT-CKD patients had reduced proximal renal cortex perfusion as well as reduced total and proximal renal cortex arterial area. Proximal renal cortex arterial area ≤0.149 cm2 identified hypertension-related CKD with a sensitivity of 71% and a specificity of 78% (AUC 0.753, p < 0.001).

CONCLUSIONS

Evidence of diminished arterial vascularity or perfusion of renal proximal cortex, both derived from US Doppler, could be helpful in differentiating hypertensive nephropathy from glomerulonephritis-related CKD.

Association of Albuminuria With Cardiac Dysfunction in US Hispanics/Latinos

Higher urine albumin-to-creatinine ratio (UACR) has been associated with cardiac dysfunction in the general population. We assessed the association of UACR with cardiac structure and function in the Echocardiographic Study of Latinos (Echo-SOL), an ancillary study of the Hispanic Community Health Study/Study of Latinos across 4 US sites. Echo-SOL participants underwent standard 2-dimensional echocardiography, including speckle-tracking strain analysis. UACR was categorized as normal and high-normal (based on the midpoint of values below microalbuminuria), microalbuminuria (≥17 mg/g for men; ≥25 mg/g for women), and macroalbuminuria (≥250 mg/g; ≥355 mg/g). Simultaneous assessments were made of left ventricular (LV) mass index and hypertrophy and measures of LV systolic and diastolic dysfunction. We assessed the association of UACR with subclinical cardiac measures, adjusting for sociodemographic and cardiometabolic factors. Among 1,815 participants (median age 54, women 65%), 42% had normal UACR, 43% high-normal UACR, 13% microalbuminuria, and 2% macroalbuminuria. Prevalence of LV hypertrophy was 13%, LV systolic dysfunction (ejection fraction <50%) 3%, and diastolic dysfunction 53%. After covariate adjustment, both micro- and macroalbuminuria were significantly associated with a twofold increase in LV hypertrophy. Microalbuminuria but not macroalbuminuria was associated with worse global longitudinal strain. Elevated UACR, even at high-normal levels, was significantly associated with greater diastolic dysfunction. In conclusion, elevated UACR was associated with LV hypertrophy and diastolic dysfunction in the largest known population sample of US Hispanic/Latinos. Screening and detection of even high-normal UACR could be of value to guide cardiovascular disease prevention efforts among Hispanic/Latino Americans.

Prevalence and Predictors of Diastolic Dysfunction According to Different Classification Criteria: The Coronary Artery Risk Development in Young in Adults Study

Heart failure with preserved ejection fraction is often preceded by diastolic dysfunction (DD). Of several published DD criteria, it is unclear which, if any, are applicable to data obtained in epidemiologic cohorts. We evaluated the prevalence of DD using previously published definitions in a population-based study, the Coronary Artery Risk Development in Young Adults (CARDIA) Study, using data gathered in 2010-2011. Echocardiography was performed on 3,474 individuals (mean age = 50.2 years) at the CARDIA year 25 examination. Four published definitions of DD were studied. We calculated DD prevalence for each definition and determined the overlap between definitions. We used logistic regression to assess the strength of associations between demographic and clinical factors and the definitions of DD. Prevalence of DD ranged from 2% to 32% across the 4 definitions, with a minority of cases identified by more than 1 definition. Two definitions classified 38%-39% of the study sample as indeterminate for DD. Associations of risk factors with DD varied considerably, with male sex being associated positively with DD for one definition (odds ratio = 1.4, 95% confidence interval: 1.2, 1.6) and inversely for another (odds ratio = 0.7, 95% confidence interval: 0.6, 0.8). Prevalence of DD varies markedly in CARDIA by the definition applied. A uniform, reliable, and accurate definition of DD for epidemiologic studies is needed.

Influence of chronic kidney disease on cardiac structure and function

Chronic kidney disease (CKD), the presence of kidney dysfunction and/or damage, is a worldwide public health issue. Although CKD is independently associated with various subtypes of cardiovascular diseases, a recent international collaborative meta-analysis demonstrates that CKD is particularly strongly associated with heart failure, suggesting its critical impact on cardiac structure and function. Although numerous studies have investigated the association of CKD and cardiac structure and function, these studies substantially vary regarding source populations and methodology (e.g., measures of CKD and/or parameters of cardiac structure and function), making it difficult to reach universal conclusions. Nevertheless, in this review, we comprehensively examine relevant studies, discuss potential mechanisms linking CKD to alteration of cardiac structure and function, and demonstrate clinical implications as well as potential future research directions. We exclusively focus on studies investigating both CKD measures, kidney function (i.e., glomerular filtration rate [GFR], creatinine clearance, or levels of filtration markers), and kidney damage represented by albuminuria, since current international clinical guidelines of CKD recommend staging CKD and assessing its clinical risk based on both GFR and albuminuria.