Renal dysfunction and acceleration of coronary disease

Factors Influencing Stent Failure in Chronic Total Occlusion Coronary Intervention

Stent failure remains one of the greatest challenges for interventional cardiologists. Despite the evolution to superior second- and third-generation drug-eluting stent designs, increasing use of intracoronary imaging and the adoption of more potent antiplatelet regimens, registries continue to demonstrate a prevalence of stent failure or target lesion revascularisation of 15-20%. Predisposition to stent failure is consistent across both chronic total occlusion (CTO) and non-CTO populations and includes patient-, lesion- and procedure-related factors. However, histological and pathophysiological properties specific to CTOs, alongside complex strategies to treat these lesions, may potentially render percutaneous coronary interventions in this cohort more vulnerable to failure. Prevention requires recognition and mitigation of the precipitants of stent failure, optimisation of interventional techniques, including image-guided precision percutaneous coronary intervention, and aggressive modification of a patient's cardiovascular risk factors. Management of stent failure in the CTO population is technically challenging and itself begets recurrence. We aim to provide a comprehensive review of factors influencing stent failure in the CTO population and strategies to attenuate these.

Adverse impact of chronic kidney disease on clinical outcomes following percutaneous coronary intervention

AIMS

We aimed to assess the impact of the severity of chronic kidney disease (CKD) with long-term clinical outcomes in patients undergoing percutaneous coronary intervention (PCI).

METHODS

We analyzed data on consecutive patients undergoing PCI enrolled in the Victorian Cardiac Outcomes Registry (VCOR) from January 2014 to December 2018. Patients were stratified into tertiles of renal function; estimated glomerular filtration (eGFR) ≥60, 30-59 and < 30 ml/min/1.73 m² (including dialysis). The primary outcome was long-term all-cause mortality obtained from linkage with the Australian National Death Index (NDI). The secondary endpoint was a composite of 30 day major adverse cardiac and cerebrovascular events.

RESULTS

We identified a total of 51,480 patients (eGFR ≥60, n = 40,534; eGFR 30-59, n = 9,521; eGFR <30, n = 1,425). Compared with patients whose eGFR was ≥60, those with eGFR 30-59 and eGFR<30 were on average older (77 and 78 vs. 63 years) and had a greater burden of cardiovascular risk factors. Worsening CKD severity was independently associated with greater adjusted risk of long-term NDI mortality: eGFR<30 hazard ratio 4.21 (CI 3.7-4.8) and eGFR 30-59; 1.8 (CI 1.7-2.0), when compared to eGFR ≥60, all p < .001.

CONCLUSION

In this large, multicentre PCI registry, severity of CKD was associated with increased risk of all-cause mortality underscoring the high-risk nature of this patient cohort.

Plasma metabolite profiles, cellular cholesterol efflux, and non-traditional cardiovascular risk in patients with CKD

BACKGROUND

Patients with chronic kidney disease (CKD) experience high rates of atherosclerotic cardiovascular disease and death that are not fully explained by traditional risk factors. In animal studies, defective cellular cholesterol efflux pathways which are mediated by the ATP binding cassette transporters ABCA1 and ABCG1 are associated with accelerated atherosclerosis. We hypothesized that cholesterol efflux in humans would vary in terms of cellular components, with potential implications for cardiovascular disease.

METHODS

We recruited 120 CKD patients (eGFR<30mL/min/1.73m²) and 120 control subjects (eGFR ≥60mL/min/1.73m²) in order to measure cholesterol efflux using either patients' HDL and THP-1 macrophages or patients' monocytes and a flow cytometry based cholesterol efflux assay. We also measured cell-surface levels of the common β subunit of the IL-3/GM-CSF receptor (IL-3Rβ) which has been linked to defective cholesterol homeostasis and may promote monocytosis. In addition, we measured plasma inflammatory cytokines and plasma metabolite profiles.

RESULTS

There was a strong positive correlation between cell-surface IL-3Rβ levels and monocyte counts in CKD (P<0.001). ABCA1 mRNA was reduced in CKD vs. control monocytes (P<0.05), across various etiologies of CKD. Cholesterol efflux to apolipoprotein A1 was impaired in monocytes from CKD patients with diabetic nephropathy (P<0.05), but we found no evidence for a circulating HDL-mediated defect in cholesterol efflux in CKD. Profiling of plasma metabolites showed that medium-chain acylcarnitines were both independently associated with lower levels of cholesterol transporter mRNA in CKD monocytes at baseline (P<0.05), and with cardiovascular events in CKD patients after median 2.6years of follow-up.

CONCLUSIONS

Cholesterol efflux in humans varies in terms of cellular components. We report a cellular defect in ABCA1-mediated cholesterol efflux in monocytes from CKD patients with diabetic nephropathy. Unlike several traditional risk factors for atherosclerotic cardiovascular disease, plasma metabolites inversely associated with endogenous cholesterol transporters predicted cardiovascular events in CKD patients. (Funded by the National Institute of Diabetes and Digestive and Kidney DiseasesK23DK097288 and others.).

Applications and Limitations of Mouse Models for Understanding Human Atherosclerosis

Most of the biological understanding of mechanisms underlying coronary artery disease (CAD) derives from studies of mouse models. The identification of multiple CAD loci and strong candidate genes in large human genome-wide association studies (GWASs) presented an opportunity to examine the relevance of mouse models for the human disease. We comprehensively reviewed the mouse literature, including 827 literature-derived genes, and compared it to human data. First, we observed striking concordance of risk factors for atherosclerosis in mice and humans. Second, there was highly significant overlap of mouse genes with human genes identified by GWASs. In particular, of the 46 genes with strong association signals in CAD GWASs that were studied in mouse models, all but one exhibited consistent effects on atherosclerosis-related phenotypes. Third, we compared 178 CAD-associated pathways derived from human GWASs with 263 from mouse studies and observed that the majority were consistent between the species.

The Relationship Between Hemodialysis and the Echocardiographic Findings in Patients with Chronic Kidney Disease

BACKGROUND

The incidence of cardiac morbidity and mortality is high in patients treated with hemodialysis (HD). The aim of this study was to evaluate the relationship between HD and the echocardiographic findings in patients with chronic kidney disease (CKD).

METHODS

Between 2012 and 2014, 150 patients with CKD. The echocardiographic data were done based on American Society of Cardiology (ASE). Measurement method for Ejection Fraction was E balling and for Diastolic Function was Tissue Doppler. Anemia, thyroid conditions and dialysis through an arteriovenous fistula or permanent catheter of dialysis for the patients are not considered.

RESULTS

The mean age at diagnosis for the patients was 57.8 years, 52.7% were males. Out of 150 patients, 112 patients (74.7%) had diabetes and 117 patients (78%) had a history of hypertension. The prevalence of all echocardiographic findings was more after the first dialysis compared with before the first dialysis in diabetic patients (P<0.05), but in non-diabetic patients, was not for the tricuspid valve stenosis, impaired right ventricular volume, systolic dysfunction and pulmonary hypertension (P>0.05).

CONCLUSIONS

According to the findings of this study, seems that more accurate selection of patients for dialysis, paying special attention to hemodynamic change during dialysis, patient education about diet and better control of uremia and diabetes is essential.

Low-dose aspirin for prevention of cardiovascular disease in patients on hemodialysis: A 5-y prospective cohort study

Introduction Aspirin is an effective antiplatelet drug for preventing cardiovascular events in high-risk subjects. However, for patients with chronic kidney disease and undergoing hemodialysis (HD), its preventive efficacy remains controversial. The present study aimed to determine whether aspirin therapy reduces the risk of cardiovascular disease (CVD) and all-cause mortality in patients on HD. Methods We conducted a 5-y prospective cohort study involving patients on HD. Major exposure variables included prescription of aspirin (100 mg/d) and no aspirin (nonaspirin). The primary outcomes included all-cause death, cardiovascular events, hemorrhage, and ischemic stroke. The secondary outcome included bleeding events defined by the requirement of hospitalization. Findings In this study, 406 patients on regular HD were involved during a 5-y follow-up. Among these, 152 and 254 propensity-matched patients were enrolled in the aspirin and nonaspirin cohort, respectively. The cumulative survival rate was not significantly higher in the aspirin than in the nonaspirin users (log rank χ²  = 1.080, P = 0.299). Aspirin use was not significantly associated with reduced all-cause mortality, fatal and nonfatal congestive heart failure, as well as acute myocardial infarction and ischemic stroke. The risk of fatal cerebral hemorrhage was not significantly increased in the aspirin users (HR = 1.795, 95% CI 0.666-4.841, P = 0.174). After adjustment for other confounders, aspirin use was also not associated with decreased risk of all-cause mortality and CVD. Discussion The present prospective cohort study suggests that low-dose aspirin use is not associated with a significant decrease in the risks of all-cause mortality, CVD, and stroke in population undergoing HD (ClinicalTrials.gov number, NCT02261025).

Neck Circumference as a Predictive Indicator of CKD for High Cardiovascular Risk Patients

Background. Neck circumference (NC) is an anthropometric measure of obesity for upper subcutaneous adipose tissue distribution which is associated with cardiometabolic risk. This study investigated whether NC is associated with indicators of chronic kidney disease (CKD) for high cardiometabolic risk patients. Methods. A total of 177 consecutive patients who underwent the outpatient departments of cardiology were prospectively enrolled in the study. The patients were aged >20 years with normal renal function or with stages 1–4 CKD. A linear regression was performed using the Enter method to present an unadjusted R², standardized coefficients, and standard error, and the Durbin-Watson test was used to assess residual independence. Results. Most anthropometric measurements from patients aged ≧65 were lower than those from patients aged <65, except for women's waist circumference (WC) and waist hip ratio. Female NC obtained the highest R² values for 24 hr CCR, uric acid, microalbuminuria, hsCRP, triglycerides, and HDL compared to BMI, WC, and hip circumference. The significances of female NC with 24 hr CCR and uric acid were improved after adjusted age and serum creatinine. Conclusions. NC is associated with indicators of CKD for high cardiometabolic risk patients and can be routinely measured as easy as WC in the future.

Anemia and associated clinical outcomes in patients with heart failure due to reduced left ventricular systolic function

BACKGROUND

Anemia is associated with decreased functional capacity, reduced quality of life, and worsened outcomes among patients with heart failure (HF) due to reduced left ventricular ejection fraction (HFREF). We sought to evaluate the independent effect of anemia on clinical outcomes among those with HFREF.

HYPOTHESIS

Anemia is associated with cardiovascular events in patients with heart failure.

METHODS

The HF-ACTION trial was a prospective, randomized trial of exercise therapy vs usual care in 2331 patients with HFREF. Patients with New York Heart Association class II to IV HF and left ventricular ejection fractions of ≤ 35% were recruited. Hemoglobin (Hb) was measured up to 1 year prior to entry and was stratified by quintile. Anemia was defined as baseline Hb <13 g/dL and <12 g/dL in men and women, respectively. Hemoglobin was assessed in 2 models: a global prediction model that had been previously developed, and a modified model including variables associated with anemia and the studied outcomes.

RESULTS

Hemoglobin was available at baseline in 1763 subjects (76% of total study population); their median age was 59.0 years, 73% were male, and 62% were Caucasian. The prevalence of anemia was 515/1763 (29%). Older age, female sex, African American race, diabetes, hypertension, and lower estimated glomerular filtration rates were all more frequent in lower Hb quintiles. Over a median follow-up of 30 months, the primary outcome of all-cause mortality or all-cause hospitalization occurred in 78% of those with anemia and 64% in those without (P < 0.001). The secondary outcomes of all-cause mortality alone,cardiovascular (CV) mortality or CV hospitalization, and CV mortality or HF hospitalization occurred in 23% vs 15%, 67% vs 54%, and 44 vs 29%, respectively (P < 0.001). Heart failure hospitalizations occurred in 36% vs 22%, and urgent outpatient visits for HF exacerbations occurred in 67% and 55%, respectively (P < 0.001). For the global model, there was an association observed for anemia and all-cause mortality or hospitalization (adjusted hazard ratio [HR]: 1.15, 95% confidence interval [CI]: 1.01-1.32, P = 0.04), but other outcomes were not significant at P < 0.05. In the modified model, the adjusted HR for anemia and the primary outcome of all-cause mortality or all-cause hospitalization was 1.25 (95% CI: 1.10-1.42, P < 0.001). There were independent associations between anemia and all-cause death (HR: 1.11, 95% CI: 0.87-1.42, P = 0.38), CV death or CV hospitalization (HR: 1.16, 95% CI: 1.01-1.33, P = 0.035), and CV death and HF hospitalization (HR: 1.27, 95% CI: 1.06-1.51, P = 0.008).

CONCLUSIONS

Anemia modestly is associated with increased rates of death, hospitalization, and HF exacerbation in patients with chronic HFREF. After adjusting for other important covariates, anemia is independently associated with an excess hazard for all-cause mortality and all-cause hospitalization. Anemia is also associated with combinations of CV death and CV/HF hospitalizations as composite endpoints.

Assessment and modeling of routinely used biochemical laboratory data of healthy individuals and end-stage renal failure (ESRF) patients by three different chemometric methods

BACKGROUND

In recent years, the use of biochemical markers has received increasing attention for purposes of risk assessment and clinical management in renal failure patients. Chemometric methods are often used in medical studies and there are already indications for their specific role as a tool of the medical statistics.

METHODS

Three chemometric methods, discriminant analysis (DA), binary logistic regression analysis (BLRA), and cluster analysis (CA), were used for assessment and modeling of routinely used biochemical laboratory data of 18 parameters that were determined from 185 healthy individuals (HIs) and 173 end-stage renal failure (ESRF) patients.

RESULTS

The above-mentioned chemometric methods were performed using the data set of 14 parameters since the rest 4 parameters did not present significant difference between healthy and patients. DA created a model using only ALB (Albumin), K (Potassium), TG (Triglyceride), and ALP (Alkaline phosphatase); BLRA model also used the above four parameters; CA classified all the cases into two clusters using the same four parameters and one more parameter, AST (aspartate aminotransferase).

CONCLUSIONS

This study provides models for assessment and modeling of routinely used biochemical laboratory data, finding groups of similarity among clinical tests usually determined on HIs and ESRF patients, contributing in data mining and reducing costs.

Long-term benefits and risks of drug-eluting compared to bare-metal stents in patients with versus without chronic kidney disease

AIMS

Chronic kidney disease (CKD) is associated with worse outcomes in patients with coronary artery disease (CAD). How CKD influences the benefit-risk balance of drug-eluting stents (DES) versus bare-metal stents (BMS) is less known.

METHODS AND RESULTS

In the multicentre BASKET-PROVE trial, 2314 patients in need of large coronary stenting (≥ 3.0mm) were randomised 2:1 to DES or BMS. In an a priori planned secondary analysis, outcomes were evaluated according to renal function defined by estimated glomerular filtration rates (eGFR; normal: eGFR ≥ 60 ml/min/1.73 m(2); CKD: eGFR<60 ml/min/1.73 m(2)). The primary endpoint was the first major adverse cardiac event (MACE: cardiac death, myocardial infarction, target vessel revascularisation) up to 2 years. A Cox proportional-hazard model was used to evaluate adjusted relative risks (hazard rates, HRs) for BMS versus DES. The interaction of stent type and renal function was tested. CKD patients (189 (11.2%)/1681 with such data) had a 2-year MACE rate of 8.5% versus 7.4% in those without CKD [HR 0.98 (0.56-1.72), p=0.95] with cardiac mortalities of 5.3% and 1.5%, respectively (p=0.002, non-significant after baseline adjustments). The MACE rate was lower in CKD patients with DES than with BMS [4.9% versus 15.2%, p=0.017, HR 0.29(0.10-0.80)] as was the MACE rate in patients without CKD [5.6% with DES versus 11.1% with BMS, p<0.0001, HR 0.51(0.35-0.75)]. No significant interaction between stent type and renal function was found.

CONCLUSIONS

This analysis of patients needing large coronary artery stenting confirms the increased mortality of CKD patients and documents a long-term benefit of DES compared to BMS irrespective of kidney function.

Mild renal dysfunction and metabolites tied to low HDL cholesterol are associated with monocytosis and atherosclerosis

BACKGROUND

The number of circulating blood monocytes impacts atherosclerotic lesion size, and in mouse models, elevated levels of high-density lipoprotein cholesterol suppress blood monocyte counts and atherosclerosis. We hypothesized that individuals with mild renal dysfunction at increased cardiovascular risk would have reduced high-density lipoprotein levels, high blood monocyte counts, and accelerated atherosclerosis.

METHODS AND RESULTS

To test whether mild renal dysfunction is associated with an increase in a leukocyte subpopulation rich in monocytes that has a known association with future coronary events, we divided individuals from the Malmö Diet and Cancer study (MDC) into baseline cystatin C quintiles (n=4757). Lower levels of renal function were accompanied by higher monocyte counts, and monocytes were independently associated with carotid bulb intima-media thickness cross-sectionally (P=0.02). Cystatin C levels were positively and plasma high-density lipoprotein cholesterol levels negatively associated with monocyte counts at baseline, after adjustment for traditional risk factors. Several amino acid metabolites tied to low levels of high-density lipoprotein cholesterol and insulin resistance measured in a subset of individuals (n=752) by use of liquid chromatography-mass spectrometry were independently associated with a 22% to 34% increased risk of being in the top quartile of monocytes (P<0.05).

CONCLUSIONS

A low high-density lipoprotein cholesterol, insulin resistance phenotype occurs in subjects with mild renal dysfunction and is associated with elevated monocytes and atherosclerosis. High blood monocyte counts may represent a previously unrecognized mechanism underlying the strong relationship between cystatin C and cardiovascular risk.

Direct Renin inhibitor: aliskiren in chronic kidney disease

The renin-angiotensin-aldosterone system (RAAS) plays pivotal roles in the pathogenesis of chronic kidney disease (CKD) progression and its increased complications such as hypertension (HT) and cardiovascular diseases (CVD). Previous studies suggested that aliskiren a direct renin inhibitor, blocks RAAS and may be effective for the management of CKD and its complications. This review focuses on the effects of aliskiren on CKD.

Aspirin for primary prevention of cardiovascular disease events

Aspirin has been used for the prevention and treatment of cardiovascular disease (CVD) for several decades. The efficacy of aspirin for secondary prevention of cardiovascular disease is well established, but the clinical benefit of aspirin for primary prevention of CVD is less clear. The primary literature suggests that aspirin may provide a reduction in CVD events, but the absolute benefit is small and accompanied by an increase in bleeding. For aspirin to be beneficial for an individual patient, the risk of a future CVD event must be large enough to outweigh the risk of bleeding. The estimation of CVD risk is multifaceted and can involve numerous risk scores and assessments of concomitant comorbidities that confer additional CVD risk. Numerous guidelines provide recommendations for the use of aspirin for primary prevention, but they often contradict one another despite being based on the same clinical trials. Additional literature suggests that the presence of comorbidities that increase CVD risk, such as diabetes mellitus, asymptomatic peripheral arterial disease, or chronic kidney disease, does not ensure that aspirin therapy will be beneficial. Ongoing clinical trials may provide additional insight, but until more data are available, an individualized assessment of CVD risk with careful evaluation of risk and benefit should be performed before recommending aspirin therapy for primary prevention of CVD.

Renal function assessed using cystatin C and antiplatelet efficacy of clopidogrel assessed using the vasodilator-stimulated phosphoprotein index in patients having percutaneous coronary intervention

Renal dysfunction is a strong independent predictor of stent thrombosis. The aim of the present study was to evaluate the strength and direction of the association between kidney function and clopidogrel efficacy. The study group consisted of consecutive patients (n = 275) who underwent stent implantation. Drug efficacy was measured using the vasodilator-stimulated phosphoprotein (VASP) index 20 ± 4 hours after clopidogrel 600 mg. Nonresponse was defined as an VASP index ≥50%. Renal function was determined using serum cystatin C. The upper reference levels are 1.12 mg/L for ≤65 years of age and 1.21 mg/L for >65 years of age. Estimated glomerular filtration was calculated using cystatin C. The median value of cystatin C was 1.16 mg/L (twenty-fifth and seventy-fifth percentiles 0.96 and 1.43); 47.63% of the study population had cystatin C above reference levels and 33.1% of patients were nonresponders to clopidogrel. No correlation was found between clopidogrel efficacy assessed with the VASP index and kidney function assessed with cystatin C (Spearman r = -0.070, p = 0.248). Based on cystatin C the proportion of nonresponders to clopidogrel was 34.4% versus 31.9% (p = 0.702) in patients with impaired renal function compared to normal renal function, respectively. The proportion of clopidogrel nonresponders did not differ (p = 0.902) among groups with normal (28.8%), mildly impaired (34.8%), moderately impaired (32.9%), and severely impaired (34.8%) renal function. In conclusion, renal function assessed by cystatin C does not predict clopidogrel efficacy. Renal dysfunction is a complex entity and its significant relation to stent thrombosis cannot be explained simply by a decrease in clopidogrel efficacy.

Diagnosis of cardiovascular disease in patients with chronic kidney disease

The major forms of cardiovascular disease including coronary atherosclerosis, valvular disease, myocardial dysfunction, and arrhythmias are observed either alone or in combination in a large fraction of patients with chronic kidney disease (CKD). As CKD progresses, these cardiovascular conditions become more prevalent and severe. The clinical implications of combined heart and kidney disease include challenges in diagnosis and management. In addition, the terminal events in CKD commonly involve one of these four domains of cardiovascular disease. This paper will explore the issue of early diagnosis of heart disease in patients with CKD with the major goal being early intervention to lessen the impact of this comorbidity.

Cardiorenal syndromes

Cardiorenal syndromes (CRS) have been subclassified as five defined entities which represent clinical circumstances in which both the heart and the kidney are involved in a bidirectional injury and dysfunction via a final common pathway of cell-to-cell death and accelerated apoptosis mediated by oxidative stress. Types 1 and 2 involve acute and chronic cardiovascular disease (CVD) scenarios leading to acute kidney injury or accelerated chronic kidney disease. Types 2 and 3 describe acute and chronic kidney disease leading primarily to heart failure, although it is possible that acute coronary syndromes, stroke, and arrhythmias could be CVD outcomes in these forms of CRS. Finally, CRS type 5 describes a simultaneous insult to both heart and kidneys, such as sepsis, where both organs are injured simultaneously. Both blood and urine biomarkers are reviewed in this paper and offer a considerable opportunity to enhance the understanding of the pathophysiology and known epidemiology of these recently defined syndromes.

Heart-kidney interaction: epidemiology of cardiorenal syndromes

Cardiac and kidney diseases are common, increasingly encountered, and often coexist. Recently, the Acute Dialysis Quality Initiative (ADQI) Working Group convened a consensus conference to develop a classification scheme for the CRS and for five discrete subtypes. These CRS subtypes likely share pathophysiologic mechanisms, however, also have distinguishing clinical features, in terms of precipitating events, risk identification, natural history, and outcomes. Knowledge of the epidemiology of heart-kidney interaction stratified by the proposed CRS subtypes is increasingly important for understanding the overall burden of disease for each CRS subtype, along with associated morbidity, mortality, and health resource utilization. Likewise, an understanding of the epidemiology of CRS is necessary for characterizing whether there exists important knowledge gaps and to aid in the design of clinical studies. This paper will provide a summary of the epidemiology of the cardiorenal syndrome and its subtypes.

Cardiorenal syndromes: pathophysiology to prevention

There is a strong association between both acute and chronic dysfunction of the heart and kidneys with respect to morbidity and mortality. The complex interrelationships of longitudinal changes in both organ systems have been difficult to describe and fully understand due to a lack of categorization of the common clinical scenarios where these phenomena are encountered. Thus, cardiorenal syndromes (CRSs) have been subdivided into five syndromes which represent clinical vignettes in which both the heart and the kidney are involved in bidirectional injury and dysfunction via a final common pathway of cell-to-cell death and accelerated apoptosis mediated by oxidative stress. Types 1 and 2 involve acute and chronic cardiovascular disease (CVD) scenarios leading to acute kidney injury (AKI) or accelerated chronic kidney disease (CKD). Types 3 and 4 describe AKI and CKD, respectively, leading primarily to heart failure, although it is possible that acute coronary syndromes, stroke, and arrhythmias could be CVD outcomes in these forms of CRS. Finally, CRSs type 5 describe a systemic insult to both heart and the kidneys, such as sepsis, where both organs are injured simultaneously in persons with previously normal heart and kidney function at baseline. Both blood and urine biomarkers, including the assessment of catalytic iron, a critical element to the generation of oxygen-free radicals and oxidative stress, are reviewed in this paper.

Impact of reduced kidney function on cardiopulmonary fitness in patients with systolic heart failure

BACKGROUND

Decreased renal function has been consistently associated with increased mortality among patients with systolic heart failure. The relationship between estimated glomerular filtration rate (eGFR) and other high-risk features including reduced cardiorespiratory fitness has not been previously reported in this patient population.

METHODS

The HF-ACTION trial was a prospective, randomized trial of exercise therapy versus usual care in patients with systolic heart failure. Patients with class 2-4 heart failure and a left ventricular ejection fraction of ≤ 35% were recruited. Serum creatinine was measured up to 1 year prior to entry. The 4-variable modified Modification of Diet in Renal Disease equation was used to calculate eGFR. Peak oxygen consumption (peak VO(2)) was directly measured using gas exchange analysis during progressive exercise testing to volitional fatigue or adverse signs/symptoms.

RESULTS

Of 2,091 subjects (mean age 59 ± 13 years, with serum creatinine available at baseline), 72% were men, and 61, 33, and 5% were Caucasians, African Americans, and others, respectively. Older age, diabetes, and hypertension were all more frequent with declining eGFR. The Pearson correlation between eGFR and peak VO(2) was 0.22 (p < 0.0001). Age was negatively correlated with both eGFR (r = -0.44, p < 0.0001) and peak VO(2) (r = -0.27, p < 0.0001). The peak VO(2) tended to decline across decreasing levels of eGFR. Individuals with an eGFR <30 ml/min/1.73 m(2) had, on average, 2.1 high-risk features including peak VO(2) <14 ml/kg/min, age >75 years, diabetes, and functional class 3-4 symptoms. Conversely, those with an eGFR >90 ml/min/1.73 m(2) had relatively few (1.0) high-risk characteristics.

CONCLUSIONS

Reduced renal filtration is associated with impaired cardiorespiratory fitness and a clustering of high-risk features in systolic heart failure patients which portend a more complicated course and higher all-cause mortality.

Amplification of atherosclerotic calcification and Mönckeberg's sclerosis: a spectrum of the same disease process

Autopsy studies have shown the near universal presence of fatty streaks and fibroatheromas in the general population from which chronic kidney disease (CKD) patients arise. The vast majority of CKD patients have multiple conventional cardiovascular risk factors. Atherosclerosis, once present, can predominantly manifest as medial calcification, which has been previously termed Mönckeberg's sclerosis. This term has also been used in rare cases to describe vascular calcinosis not related to CKD. This clarification is critical to advance the field in terms of pathological diagnosis and treatment of CKD bone and mineral disorder. Factors that appear to promote the osteoblastic transformation of vascular smooth muscle cells and enhance deposition of calcium hydroxyapatite crystals include phosphorus activation of the Pit-1 receptor, bone morphogenic proteins 2 and 4, leptin, endogenous 1,25 dihydroxy vitamin D, vascular calcification activating factor, and measures of oxidative stress. These entities work to accelerate the atherosclerotic process in CKD patients and may be future targets for diagnosis and treatment. Although conventional atherosclerotic risk factors should be optimally managed, it should be noted that trials of hydroxymethylglutaryl-CoA reductase inhibitors have failed to attenuate the rate of progressive vascular calcification as measured by computed tomography scans.

Chronic kidney disease, prevalence of premature cardiovascular disease, and relationship to short-term mortality

BACKGROUND

Chronic kidney disease (CKD) is recognized as an independent cardiovascular disease (CVD) risk state, particularly in the elderly, and has been defined by levels of estimated glomerular filtration rate (eGFR) and markers of kidney damage. The relationship between CKD and CVD in younger and middle-aged adults has not been fully explored.

METHODS

Community volunteers completed surveys regarding past medical events and underwent blood pressure and laboratory testing. Chronic kidney disease was defined as an eGFR <60 mL x min(-1) x 1.73 m(-2) or urine albumin-creatinine ratio (ACR) > or =30 mg/g. Premature CVD was defined as self-reported myocardial infarction or stroke at <55 years of age in men and <65 years of age in women. Mortality was ascertained by linkage to national data systems.

RESULTS

Of 31 417 participants, the mean age was 45.1 +/- 11.2 years, 75.5% were female, 36.8% African American, and 21.6% had diabetes. A total of 20.6% were found to have CKD, with the ACR and eGFR being the dominant positive screening tests in the younger and older age deciles, respectively. The prevalences of premature myocardial infarction (MI), stroke, or death, and the composite were 5.3%, 4.7%, 0.8%, 9.2%, and 2.5%, 2.2%, 0.2%, 4.2% for those with and without CKD, respectively (P < .0001 for composite). Multivariable analysis found CKD (OR 1.44, 95% CI 1.27-1.63), age (OR 1.05 [per year], 95% CI 1.04-1.06), hypertension (OR 1.61, 95% CI 1.40-1.84), diabetes (OR 2.03, 95% CI 1.79-2.29), smoking (OR 1.91, 95% CI 1.66-2.21), and less than high school education (OR 1.59, 95% CI 1.37-1.85) as the most significantly associated factors for premature CVD or death (all P < .0001). Survival analysis found those with premature MI or stroke and CKD had the poorest short-term survival over the next 3 years after screening.

CONCLUSIONS

Chronic kidney disease is an independent predictor of MI, stroke, and death among men and women younger than age 55 and 65 years, respectively. These data suggest the biologic changes that occur with kidney failure promote CVD at an accelerated rate that cannot be fully explained by conventional risk factors or older age. Screening for CKD by using both the ACR and eGFR can identify younger and middle-aged individuals at high risk for premature CVD and near-term death.

Accelerated atherosclerotic calcification and Monckeberg's sclerosis: a continuum of advanced vascular pathology in chronic kidney disease

Autopsy studies have demonstrated the near universal presence of fatty streaks and fibroatheromas in the general population from which patients with chronic kidney disease (CKD) arise. The vast majority of patients with CKD have multiple conventional cardiovascular risk factors. Vascular atherosclerotic calcification develops in most patients as they transition from the general population to significant CKD as part of cholesterol crystallization within atherosclerotic lesions. Once present, however, atherosclerotic medial calcification can become prominent and has been previously identified as Mönckeberg's sclerosis. A unifying concept supported by the preponderance of pathologic evidence contends that Mönckeberg's sclerosis is a manifestation of accelerated atherosclerosis in patients with CKD. The term has also been used in rare cases to describe vascular calcinosis not related to CKD. This clarification is critical to advance the field in terms of pathologic diagnosis and treatment of CKD bone and mineral disorder. Factors that seem to promote the osteoblastic transformation of vascular smooth muscle cells and enhance deposition of calcium hydroxyapatite crystals include phosphorus activation of the Pit-1 receptor, bone morphogenic proteins 2 and 4, leptin, endogenous 1,25 dihydroxyvitamin D, vascular calcification activating factor, and measures of oxidative stress. These entities work to accelerate the atherosclerotic process in patients with CKD and may be future targets for diagnosis and treatment because randomized trials with hydroxymethylglutaryl-CoA reductase inhibitors have failed to attenuate the rate of progressive vascular calcification.

Chronic kidney disease as a cardiovascular risk state and considerations for the use of statins

Chronic kidney disease (CKD) creates one of the highest risk atherosclerotic states that can occur in human beings. The use of 3-hydroxy-3-methylglutaryl coenzyme reductase inhibitors (statins) has gained widespread acceptance in the general population for the purposes of lowering low-density lipoprotein cholesterol (LDL-C) and reducing the future risks of myocardial infarction, stroke, and cardiac death. In patients with CKD, the balance of benefits and risks of statins appears to be different than that in the general population. Reductions in LDL-C with statins may be associated with a reduced progression of CKD. Importantly, recent studies suggest statins are associated with a reduction in rates of acute kidney injury, mediated by ischemic insults and oxidative stress, after cardiac surgery and exposure to iodinated contrast. A reduction in cardiovascular events with LDL-C reduction in CKD and dialysis patients is yet to be proven. In addition, studies suggest that there are higher adverse drug effects with statins in CKD. This work will address the benefits and risks of this important treatment option for the growing population of patients with CKD, who have not undergone renal transplantation, and are at very high risk of cardiovascular events.

Statin therapy in renal disease: harmful or protective?

Chronic kidney disease (CKD) creates one of the highest-risk atherosclerotic states that can occur in human beings. The use of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) has gained widespread acceptance in the general population for the purposes of lowering low-density lipoprotein cholesterol (LDL-C) and reducing the future risks of myocardial infarction, stroke, and cardiac death. In patients with CKD, these benefits are believed to be enjoyed to the same or greater degrees. Reductions in LDL-C with statins may be associated with a reduced progression of CKD. Importantly, recent studies suggest statins are associated with a reduction in rates of acute renal failure after cardiopulmonary bypass surgery and exposure to iodinated contrast. In patients with end-stage renal disease (ESRD), recent data suggest that the annual rate of coronary artery calcification can be attenuated or reduced with LDL-C reduction. However, two large trials demonstrating LDL-C reduction with statins and with these drugs have failed to demonstrate a reduction in cardiovascular events in ESRD. Thus, the potential benefits of statins and LDL-C reduction in CKD have to be considered in light of evidence suggesting a reduced benefit, if any, in patients with ESRD. In addition, studies suggest that there are higher adverse drug effects with statins in CKD.

Coronary Artery Disease

Coronary heart disease is the most common cause of death in the general population and in patients with ESRD. The principles of cardiovascular risk assessment and management apply to both populations. Advances in noninvasive coronary artery imaging have improved early detection of subclinical disease. The goals of medical management of coronary disease are to modify the natural history of disease and to improve the symptoms of angina. Coronary revascularization poses a different risk and benefit equation in the ESRD population. In stable ESRD with multivessel coronary artery disease, coronary bypass surgery, despite the upfront risks of stroke, myocardial infarction, and chest wound infection, seems to be a favored approach. In patients with ESRD and acute coronary syndromes, percutaneous coronary intervention on the target vessel has been associated with the most favorable outcomes. This article explores the clinical issues with respect to coronary artery disease in patients with ESRD.

Amey S, Polanczyk CAA. Prognostic value of serum biomarkers in association with TIMI risk score for acute coronary syndromes

BACKGROUND

Markers of neurohormonal activation and inflammation play a pivotal role in non-ST-elevation acute coronary syndromes (NSTE-ACS).

HYPOTHESIS

We hypothesized that other biochemical markers could add prognostic value on Thrombolysis In Myocardial Infarction (TIMI) risk score to predict major cardiovascular events in patients with NSTE-ACS.

METHODS

In a cohort of 172 consecutive patients with NSTE-ACS, TIMI score was assessed in the first 24 h, and blood samples were collected for measurement of N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitivity C-reactive protein, CD40 ligand, and creatinine. Major clinical outcomes (death and cardiovascular hospitalization) were accessed at 30 days and 6 months. Multivariate logistic regression was applied to identify markers significantly associated with outcomes and, based on individual coefficients, an expanded score was developed.

RESULTS

Of 172 patients, 42% had acute myocardial infarction. The unadjusted 30-day event rate increased with age (odds ratio [OR] = 1.03; 95% confidence interval [CI] 1.00-1.06), creatinine (OR = 2.4; 1.4-4.1), TIMI score (OR = 1.6; 1.2-2.2), troponin I (OR = 3.4; 1.5-7.7), total CK (OR = 2.7; 1.2-6.1), and NT-proBNP (OR = 2.9; 1.3-6.3) levels. In multivariate analysis, TIMI risk score, creatinine, and NT-proBNP remained associated with worse prognosis. Multimarker Expanded TIMI Risk Score [TIMI score + (2 X creatinine [in mg/dl]) + (3, if NT-proBNP > 400 pg/ml)] showed good accuracy for 30-day (c statistic 0.77; p < 0.001) and 6-month outcomes (c statistic 0.75; p < 0.001). The 30-day event rates according to tertiles of expanded score were 7, 26, and 75%, respectively (p < 0.01).

CONCLUSION

In NSTE-ACS, baseline levels of NT-proBNP and creatinine are independently related to cardiovascular events. Both markers combined with TIMI risk score provide a better risk stratification than either test alone.

Statin therapy in renal disease: Harmful or protective?

Chronic kidney disease (CKD) creates one of the highest-risk atherosclerotic states that can occur in human beings. The use of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) has gained widespread acceptance in the general population for the purposes of lowering low-density lipoprotein cholesterol (LDL-C) and reducing the future risks of myocardial infarction, stroke, and cardiac death. In patients with CKD, these benefits are believed to be enjoyed to the same or greater degrees. Reductions in LDL-C with statins may be associated with a reduced progression of CKD. Importantly, recent studies suggest statins are associated with a reduction in rates of acute renal failure after cardiopulmonary bypass surgery and exposure to iodinated contrast. In patients with end-stage renal disease (ESRD), recent data suggest that the annual rate of coronary artery calcification can be attenuated or reduced with LDL-C reduction. However, two large trials demonstrating LDL-C reduction with statins and with these drugs have failed to demonstrate a reduction in cardiovascular events in ESRD. Thus, the potential benefits of statins and LDL-C reduction in CKD have to be considered in light of evidence suggesting a reduced benefit if any, in patients with ESRD. In addition, studies suggest that there are higher adverse drug effects with statins in CKD.

B-Type Natriuretic Peptide and the Risk of Cardiovascular Events and Death in Patients With Stable Angina

OBJECTIVES

The aim of this study was to assess the predictive value of the cardiac hormone B-type natriuretic peptide (BNP) for long-term outcome in a large cohort of stable angina patients.

BACKGROUND

Recent data suggest a role of BNP in stable ischemic heart disease beyond its known value in heart failure and acute coronary syndromes.

METHODS

In 1,085 patients with coronary artery disease (CAD) baseline levels of BNP were prospectively associated with cardiovascular (CV) events during a mean follow-up of 2.5 years.

RESULTS

BNP concentrations were significantly elevated in patients with future CV events (median [25th/75th interquartile range] 119.2 [43.6/300.4] pg/ml vs. 36.2 [11.3/94.6] pg/ml; p < 0.001). Kaplan-Meier survival analysis showed a stepwise decrease in event-free survival across quartiles of BNP baseline concentration (p(log rank) < 0.001). Patients in the highest quartile revealed a 6.1-fold increased risk (p = 0.001) compared to patients in the lowest quartile after adjustment for potential confounders. For a cut-off value of 100 pg/ml, an independently increased risk of adverse outcome (hazard ratio [HR] 4.4; p < 0.001) could be demonstrated. One standard deviation (SD) decrease in ejection fraction implied the most prominent increase in risk of future CV events (HR 1.69; p < 0.001) followed by one SD increase in BNP (HR 1.53; p < 0.001). The highest prognostic accuracy could be demonstrated for BNP (area under the curve 0.671).

CONCLUSIONS

The data of this large group of CAD patients provide independent evidence that BNP is a strong predictor of cardiovascular risk in patients with stable angina independent of left ventricular systolic performance and known risk factors.

Evaluation and treatment of coronary artery disease in patients with end-stage renal disease

Evaluation and treatment of coronary artery disease in patients with end-stage renal disease. Patients with end-stage renal disease (ESRD) are at increased risk of death from coronary artery disease (CAD). The metabolic milieu that results from renal dysfunction appears to accelerate the atherosclerotic process by decades in patients with ESRD. The extremely high prevalence of atherosclerosis in patients with ESRD mandates risk factor identification and treatment. Traditionally, CAD in this patient population has been treated conservatively. Analysis of large databases has highlighted the scope and complexity of this problem; nonetheless, there is a paucity of randomized, controlled trials of CAD in patients with ESRD. In this paper the following issues related to evaluation and treatment of patients with chronic kidney disease are addressed: (1) optimal CAD risk management; (2) evaluation for CAD in patients with ESRD, including the identification of coronary calcification; (3) treatment of CAD with medical therapy and revascularization; (4) relative merits of percutaneous coronary intervention versus bypass surgery. In general, an aggressive approach to medical management of CAD is warranted, even in the setting of subclinical CAD. A low threshold for diagnostic testing should be employed in patients with ESRD. When significant CAD is identified, ESRD patients appear to benefit more from revascularization compared to conservative medical management. Thus, if clinically reasonable, patients with ESRD and CAD should be managed aggressively to improve survival and reduce the incidence of future cardiac events.

Risk factors for atherosclerotic vascular disease

Several controlled interventional trials have shown the benefit of anti-hypertensive and hypolipidaemic drugs for the prevention of coronary heart disease (CHD). International guidelines for the prevention of CHD agree in their recommendations for tertiary prevention and recommend lowering the blood pressure to below 140 mm/90 mm Hg and low density lipoprotein (LDL)-cholesterol to below 2.6 mmol/l in patients with manifest CHD. Novel recommendations for secondary prevention are focused on the treatment of the pre-symptomatic high-risk patient with an estimated CHD morbidity risk of higher than 20% per 10 years or an estimated CHD mortality risk of higher than 5% per 10 years. For the calculation of this risk, the physician must record the following risk factors: sex, age, family history of premature myocardial infarction, smoking, diabetes, blood pressure, total cholesterol, LDL-cholesterol, high-density lipoprotein (HDL)-cholesterol, and triglyceride. This information allows the absolute risk of myocardial infarction to be computed by using scores or algorithms which have been deduced from results of epidemiological studies. To improve risk prediction and to identify new targets for intervention, novel risk factors are sought. High plasma levels of C-reactive protein has been shown to improve the prognostic value of global risk estimates obtained by the combination of conventional risk factors and may influence treatment decisions in patients with intermediate global cardiovascular risk (CHD morbidity risk of 10%-20% per 10 years or CHD mortality risk of 2%-5% per 10 years).