Chronic kidney disease is associated with angiographic coronary artery disease

Cause of Death in Patients with Reduced Kidney Function

Information on common causes of death in people with CKD is limited. We hypothesized that, as eGFR declines, cardiovascular mortality and mortality from infection account for increasing proportions of deaths. We calculated eGFR using the CKD Epidemiology Collaboration equation for residents of Alberta, Canada who died between 2002 and 2009. We used multinomial logistic regression to estimate unadjusted and age- and sex-adjusted differences in the proportions of deaths from each cause according to the severity of CKD. Cause of death was classified as cardiovascular, infection, cancer, other, or not reported using International Classification of Diseases codes. Among 81,064 deaths, the most common cause was cancer (31.9%) followed by cardiovascular disease (30.2%). The most common cause of death for those with eGFR≥60 ml/min per 1.73 m(2) and no proteinuria was cancer (38.1%); the most common cause of death for those with eGFR<60 ml/min per 1.73 m(2) was cardiovascular disease. The unadjusted proportion of patients who died from cardiovascular disease increased as eGFR decreased (20.7%, 36.8%, 41.2%, and 43.7% of patients with eGFR≥60 [with proteinuria], 45-59.9, 30-44.9, and 15-29.9 ml/min per 1.73 m(2), respectively). The proportions of deaths from heart failure and valvular disease specifically increased with declining eGFR along with the proportions of deaths from infectious and other causes, whereas the proportion of deaths from cancer decreased. In conclusion, we found an inverse association between eGFR and specific causes of death, including specific types of cardiovascular disease, infection, and other causes, in this cohort.

How do We Manage Coronary Artery Disease in Patients with CKD and ESRD?

Chronic kidney disease (CKD) has been shown to be an independent risk factor for cardiovascular events. In addition, patients with pre-dialysis CKD appear to be more likely to die of heart disease than of kidney disease. CKD accelerates coronary artery atherosclerosis by several mechanisms, notably hypertension and dyslipidemia, both of which are known risk factors for coronary artery disease. In addition, CKD alters calcium and phosphorus homeostasis, resulting in hypercalcemia and vascular calcification, including the coronary arteries. Mortality of patients on long-term dialysis therapy is high, with age-adjusted mortality rates of about 25% annually. Because the majority of deaths are caused by cardiovascular disease, routine cardiac catheterization of new dialysis patients was proposed as a means of improving the identification and treatment of high-risk patients. However, clinicians may be uncomfortable exposing asymptomatic patients to such invasive procedures like cardiac catheterization, thus noninvasive cardiac risk stratification was investigated widely as a more palatable alternative to routine diagnostic catheterization. The effective management of coronary artery disease is of paramount importance in uremic patients. The applicability of diagnostic, preventive, and treatment modalities developed in nonuremic populations to patients with kidney failure cannot necessarily be extrapolated from clinical studies in non-kidney failure populations. Noninvasive diagnostic testing in uremic patients is less accurate than in nonuremic populations. Initial data suggest that dobutamine echocardiography may be the preferred diagnostic method. PCI with stenting is a less favorable alternative to CABG, however, it has a faster recovery time, reduced invasiveness, and no overall mortality difference in nondiabetic and non-CKD patients compared with CABG. CABG is associated with reduced repeat revascularizations, greater relief of angina, and increased long term survival. However, CABG is associated with a higher incidence of post-operative risks. The treatment chosen for each patient should be an individualized decision based upon numerous risk factors. CKD is associated with higher rates of CAD, with 44% of all-cause mortality attributable to cardiac disease and about 20% from acute MI. Optimal treatment including aggressive lifestyle modifications and concomitant medical therapy should be implemented in all patients to maximize benefits from either PCI or CABG. Future prospective randomized controlled trials with newer second or third generation DES and bioabsorbable DES are necessary to determine if PCI may be non-inferior to CABG in the future.

The management of acute coronary syndromes in patients with chronic kidney disease

Coronary heart disease is highly prevalent in patients with CKD, and survival after acute coronary syndrome (ACS) is worse compared with the general population. Many trials that define guidelines for cardiovascular disease excluded patients with kidney disease, leaving a gap between the evidence base and clinical reality. The underlying pathophysiology of vascular disease appears to be different in the setting of CKD. Patients with CKD are more likely to present with myocardial infarction and less likely to be diagnosed with ACS on admission compared with the general population. Patients with CKD appear to benefit with angiography and revascularization compared with medical management alone. However, the increased risk of in-hospital bleeding and risk of contrast-induced acute kidney injury are 2 factors that can limit overall benefit for some. Thus, judicious application of available therapies for the management of ACS is warranted to extend survival and reduce hospitalizations in this high-risk population. In this review, we highlight the clinical challenges and potential solutions for managing ACS in patients with CKD.

Recent advances in the management of hemodialysis patients: a focus on cardiovascular disease

The number of patients requiring chronic hemodialysis is rapidly growing worldwide. Hemodialysis both greatly reduces quality of life and is associated with extremely high mortality rates. Management of care of patients requiring chronic hemodialysis is complex, and randomized controlled trials aimed at reducing primary outcomes of cardiovascular disease events, mortality, or both in this population have largely been unsuccessful. Topics of major concern in the management of maintenance hemodialysis patients as related to these outcomes include the overall cardiovascular disease burden, blood pressure control, anemia, abnormalities in mineral metabolism, and inflammation. The focus of this review is a discussion of these topics on the basis of current recommendations from major organizations, expert opinion, and the available randomized controlled trials to date. These issues are further complicated by sometimes conflicting observational and randomized controlled trial data. Overall, treatment options for reducing these endpoints in maintenance hemodialysis patients are limited, and future randomized controlled trials are essential to continuing to advance care in this population, with the goal of ultimately improving hard outcomes. Such trials should consider new therapies to better target these factors, additional risk factors that have not been well tested to date, and therapies with new targets, including inflammation.

Left atrial volume and adverse cardiovascular outcomes in unselected patients with and without CKD

BACKGROUND AND OBJECTIVES

Patients with CKD have increased cardiovascular morbidity and mortality. This study investigated the prognostic value of common clinical echocardiographic parameters.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

There were 289 unselected consecutive patients who had a transthoracic echocardiogram between January and June 2003. Patients with stage 3 or 4 CKD (n=49) were compared with those with eGFR≥60 ml/min per 1.73 m(2), n=240). Left ventricular volume, ejection fraction and mass, left atrial volume, and function parameters were measured. The primary endpoint, determined a priori, was a composite of cardiac death, myocardial infarction, and congestive cardiac failure.

RESULTS

Patients were followed for a median 5.6 years. The incidence of the primary endpoint was higher in patients with CKD (29% versus 12%, P=0.001), who were older and had a higher prevalence of hypertension and ischemic heart disease. Indexed left ventricular mass (LVMI) and left atrial volume (LAVI) were higher in patients with CKD. Furthermore, patients with LAVI>32 ml/m(2) had significantly lower event-free survival than patients with normal (<28 ml/m(2)) or mildly dilated LAVI (28-32 ml/m(2)) (P<0.001). Multivariate analysis showed that age (odds ratio [OR], 1.19; 95% confidence interval [95% CI], 1.08 to 1.31; P=0.001) and LVMI (OR, 3.66; 95% CI, 2.47 to 5.41; P<0.001) were independently associated with LAVI>32 ml/m(2). Multivariate Cox regression analysis demonstrated that CKD (hazard ratio [HR], 1.13; 95% CI, 1.01 to 1.26; P=0.04), hypertension (HR, 2.18; 95% CI, 1.05 to 4.54; P=0.04), and a larger LAVI (HR, 1.35; 95% CI, 1.02 to 1.77; P=0.04) were independent predictors of the primary endpoint.

CONCLUSIONS

Patients with CKD were at higher risk for cardiovascular events. LAVI was significantly larger in the CKD group and was a predictor of adverse cardiac events.

Cardiovascular complications of diabetic kidney disease

Diabetic nephropathy is the most common cause of CKD and represents a large and ominous public health problem. Patients with diabetic kidney disease have exceptionally high rates of cardiovascular morbidity and mortality. In fact, the excess mortality among patients with diabetes appears to be largely limited to the subgroup with kidney disease and explained by their high burden of cardiovascular disease. The mechanisms underlying the strong association between diabetic kidney disease and various forms of cardiovascular disease are poorly understood. Traditional risk factors for cardiovascular disease, although prevalent among those with diabetes, do not fully account for the heightened risk observed. Despite their susceptibility to cardiovascular disease, patients with CKD are less likely to receive appropriate risk factor modification than the general population. Moreover, because patients with CKD have commonly been excluded from major cardiovascular trials, the evidence for potential treatments remains limited. The mainstays of treatment for diabetic kidney disease currently include blockade of the renin-angiotensin-aldosterone system and control of hypertension, hyperglycemia, and dyslipidemia. Increased awareness of the vulnerability of this patient population and more timely interventions are likely to improve outcomes while large evidence gaps are filled with newer studies.

Coronary artery disease in patients with chronic kidney disease: a clinical update

Chronic kidney disease (CKD) is an independent risk factor for coronary artery disease (CAD). Coronary artery disease is the leading cause of morbidity and mortality in patients with CKD. The outcomes of CAD are poorer in patients with CKD. In addition to traditional risk factors, several uremia-related risk factors such as inflammation, oxidative stress, endothelial dysfunction, coronary artery calcification, hyperhomocysteinemia, and immunosuppressants have been associated with accelerated atherosclerosis. A number of uremia-related biomarkers are identified as predictors of cardiac outcomes in CKD patients. The symptoms of CAD may not be typical in patients with CKD. Both dobutamine stress echocardiography and radionuclide myocardial perfusion imaging have moderate sensitivity and specificity in detecting obstructive CAD in CKD patients. Invasive coronary angiography carries a risk of contrast nephropathy in patients with advanced CKD. It should be reserved for those patients with a high risk for CAD and those who would benefit from revascularization. Guideline-recommended therapies are, in general, underutilized in renal patients. Medical therapy should be considered the initial strategy for clinically stable CAD. The effects of statins in patients with advanced CKD have been neutral despite a lipid-lowering effect. Compared to non-CKD population, percutaneous coronary intervention (PCI) is associated with higher procedure complications, restenosis, and future cardiac events even in the drug-eluting stent era in patients with CKD. Compared with PCI, coronary artery bypass grafting (CABG) reduces repeat revascularizations but is associated with significant perioperative morbidity and mortality. Screening for CAD is an important part of preoperative evaluation for kidney transplant candidates.

Cardiorenal syndrome

Cardiorenal syndrome (CRS) includes a broad spectrum of diseases within which both the heart and kidneys are involved, acutely or chronically. An effective classification of CRS in 2008 essentially divides CRS in two main groups, cardiorenal and renocardiac CRS, based on primum movens of disease (cardiac or renal); both cardiorenal and renocardiac CRS are then divided into acute and chronic, according to onset of disease. The fifth type of CRS integrates all cardiorenal involvement induced by systemic disease. This article addresses the pathophysiology, diagnosis, treatment, and outcomes of the 5 distinct types of CRS.

Decreased renal function is an independent predictor of severity of coronary artery disease: an application of Gensini score

Coronary artery disease (CAD) is the leading cause of death in patients with chronic kidney disease (CKD).Although many studies have shown a higher prevalence of CAD among these patients, the association between the spectrum of renal dysfunction and severity of CAD remains unclear. In this study, we investigate the association between renal function and the severity of CAD. We retrospectively reviewed the medical records of 1,192 patients who underwent elective coronary angiography (CAG). The severity of CAD was evaluated by Gensini score according to the degree of luminal narrowing and location(s) of obstruction in the involved main coronary artery. In all patients, the estimated glomerular filtration rate (eGFR) was independently associated with Gensini score (β=-0.27, P < 0.001) in addition to diabetes mellitus (β=0.07, P = 0.02), hypertension (β=0.12, P < 0.001), low density lipoprotein (LDL)-cholesterol (β=0.08, P = 0.003), and hemoglobin (β=-0.07, P = 0.03) after controlling for other confounding factors. The result of this study demonstrates that decreased renal function is associated not only with the prevalence, but also the severity, of CAD.

Relation of estimated glomerular filtration rate to the presence of coronary plaque and obstructive coronary artery disease in a zero or low coronary artery calcium score

OBJECTIVES

Although renal dysfunction is associated with the presence of atherosclerosis, little is known about the relationship between reduced estimated glomerular filtration rate (eGFR) and the presence of atherosclerosis detected by coronary computed tomographic angiography (CCTA). This study evaluated the relation of eGFR to the presence of coronary plaque and obstructive coronary artery disease (CAD) in patients with a zero or low coronary artery calcium score (CACS).

METHODS

Coronary artery calcium scoring and CCTA were performed with CT scanners. Serum creatinine was measured before CCTA, and GFR was estimated. A total of 720 patients with a CACS ≤ 10 were enrolled.

RESULTS

Coronary plaque was detected in 118 patients. Of the 118 patients, 36 had a diagnosis of obstructive CAD. The multiple-adjusted odds ratios of presenting with coronary plaque and obstructive CAD were 1.82 (95% CI 1.06-3.12, p = 0.030) and 1.79 (95% CI 0.71-4.49, p = 0.217) for the lowest tertile of eGFR compared with the highest tertile, respectively.

CONCLUSIONS

Lower eGFR levels were associated with the presence of coronary plaque in patients with a zero or low CACS. However, the association between eGFR and the presence of obstructive CAD was not statistically significant.

Elevated serum bone morphogenetic protein 4 in patients with chronic kidney disease and coronary artery disease

Chronic kidney disease (CKD) is associated with increased coronary artery disease (CAD) and coronary artery calcification. We hypothesized that the osteogenic factor, bone morphogenetic protein-4 (sBMP-4), is elevated in subjects with both CKD and CAD. Serum was collected from 79 subjects undergoing diagnostic angiography and stratified according to CAD and CKD status. Subjects with both CAD and CKD had significantly elevated sBMP-4 compared to those with only one or no disease. sBMP-4 continued to be associated with the presence of both diseases after adjustment for other risk factors. To determine if sBMP-4 is associated with coronary artery calcification, we compared coronary artery calcium scores (CAC) to sBMP-4 in 22 subjects. A positive correlation between CAC and sBMP-4 was seen. In conclusion, sBMP-4 is elevated in patients with both CAD and CKD and positively correlates with CAC, suggesting a role for sBMP-4 in the increased CAD seen in CKD patients.

Transradial approach for cardiovascular interventions and its implications for hemodialysis vascular access

Because of its advantages, the transradial approach for cardiovascular interventions has gained significant popularity. However, this approach can be associated with radial artery thrombosis and occlusion. The complication generates a major concern for its potential impact on the future creation of an arteriovenous hemodialysis access. The issue gains more importance as a significant number of patients with cardiovascular disease suffer from underlying chronic kidney disease (CKD) and might need an arteriovenous access for hemodialysis therapy. In this context, the preservation of the arterial system is of equal importance to the frequently highlighted venous conservation for the successful creation of an arteriovenous access. It is for this reason that the Fistula First Breakthrough Initiative recommends avoiding the use of the radial artery for performing percutaneous interventions in patients with advanced CKD. Furthermore, there is scarce clinical data and publication regarding the impact of transradial approach on hemodialysis access. Is it possible to utilize the potential benefits and minimize the potential risks of transradial approach in chronic kidney disease patients? On the basis of current knowledge, this review discusses related issues of transradial approach to raise awareness and understanding, which are essential to proper caring of CKD patients undergoing cardiovascular interventions.

Of heart and kidney: a complicated love story

The multiple connections that exist between the cardiovascular system and the kidney lead to a complex cardiovascular and renal medicine relationship. It is well established in the literature that chronic kidney disease (CKD) is an important and independent risk factor for cardiovascular disease (CVD). The prevalence of CKD in the general population is about 7%, comparable with the prevalence of diabetes. The main causes of CKD are diabetes and hypertension, worldwide. The prevalence of CVD in the CKD population ranges between 7 and 85% according to the CKD stage and type, and the patient diagnosed with CKD has a higher risk of dying of CVD than of starting renal replacement therapy. There are some particular aspects of CVD in CKD patients that differ from the general population, making its prevention and treatment a challenge for both cardiologists and nephrologists.

Decreased estimated glomerular filtration rate (eGFR) is not an independent risk factor of arterial stiffness in Chinese women

Recent studies suggest that decreased estimated glomerular filtration rate (eGFR) and uric acid (UA) may be independent risk factors for arterial stiffness (AS). As serum UA level is linked to renal function, we hypothesize that decreased eGFR may be not an independent risk factor of AS, but may be related to UA level. In this study, we aimed to validate this hypothesis in a large community-based Chinese population. A total of 13,899 people were selected from the Cardiovascular Risk Survey (CRS) from October 2007 to March 2010. Pulse wave velocity (PWV) was calculated using the established methods. The relationships between eGFR, fasting blood glucose (FBG), UA and PWV were analyzed with multivariate linear regression. We found that PWV was significantly correlated to FBG (r = 0.173, p < 0.001) and UA (r = 0.177, p < 0.001), and inversely correlated to eGFR (r = - 0.161, p < 0.001). A multivariable regression analysis revealed that FBG (β = 0.056, p < 0.001) and UA (β = 0.039, p < 0.001), but not eGFR (β = - 0.011, p = 0.062) were significantly related to elevation of PWV. In women, eGFR was not an independent risk factor of AS with progressively decreasing renal function (all p > 0.05). However, in men, eGFR was associated with PWV in subjects with eGFR < 60 ml/min/1.73 m(2). Our results suggest that decreased eGFR is not independently associated with AS in Chinese women.

In-hospital mortality in patients with renal dysfunction admitted for myocardial infarction: the Emilia-Romagna region of Italy database of hospital admissions

BACKGROUND

In-hospital mortality of patients with myocardial infarction (MI) in different European populations and renal dysfunction is variable. We aimed to evaluate in-hospital mortality for MI in chronic kidney disease (CKD), in end-stage renal disease (ESRD), and in subjects admitted for MI without renal dysfunction living in the Emilia-Romagna region of Italy.

METHODS

We considered all cases of MI (first event) recorded in the database of hospital admissions of the region Emilia-Romagna of Italy, from January 1999 to December 2009. The criterion for inclusion was the presence, as a first discharge diagnosis, of acute MI (International Classification of Diseases, 9th Revision, Clinical Modification). The Charlson comorbidity index (CCI), with the exclusion of CKD, was calculated. The outcome variable was in-hospital mortality for MI, and its association with comorbidities, CKD and ESRD, was analyzed.

RESULTS

During the considered period, 88,014 cases of first MI were recorded. The percentage of patients admitted with MI and died during hospitalization were higher in patients with ESRD (38.3 %) and CKD (16.5 %) than in those without renal dysfunction (14 %) (p < 0.01). In CKD and ESRD patients, data of in-hospital mortality for MI exhibited a twofold increase in the analyzed period. In-hospital mortality for MI was independently associated with age (OR 1.077, 95 % CI 1.075-1.080, p < 0.001), CCI excluding CKD (OR 1.101, 95 % CI 1.069-1.134, p < 0.001), cerebrovascular disease (OR 1.450, 95 % CI 1.349-1.557, p < 0.001), malignancy (OR 1.234, 95 % CI 1.153-1.320, p < 0.001), and ESRD (OR 4.137, 95 % CI 3.511-4.875, p < 0.001).

CONCLUSIONS

As for the Emilia-Romagna region of Italy, in-hospital mortality for MI is increasing over the last years, and mortality seems to be related with patients' comorbidities and presence of advanced stages of CKD.

Value and level of circulating endothelial progenitor cells, angiogenesis factors and mononuclear cell apoptosis in patients with chronic kidney disease

BACKGROUND

Chronic renal failure on dialysis can reduce the number of circulating endothelial progenitor cells (EPCs), but this biomarker has not been fully investigated in patients with chronic kidney disease (CKD). A link between CKD and increased mononuclear cell apoptosis (MCA) in circulation has been reported but the effect of vascular endothelial growth factor (VEGF) and stromal cell-derived factor (SDF)-1α, two angiogenesis factors, on circulating EPC levels in CKD has not been clarified. This study examined the relationships between the numbers of circulating EPCs and the severity of CKD, degree of MCA and serum levels of VEGF and SDF-1α in CKD patients.

METHODS

The numbers of circulating EPCs (CD31/CD34+, CD62E/CD34+, KDR/CD34+, CXCR4/CD34+) were measured in 166 patients with varying degrees of CKD under regular treatment at an outpatient department and in 30 volunteer control subjects.

RESULTS

CKD patients had significantly lower numbers of EPCs (p < 0.007), higher MCA in circulation and higher serum levels of VEGF and SDF-1 compared with the control subjects (all p < 0.001). Compared with patients with early CKD (stages I-III), patients with late CKD [stage IV-V or end-stage renal disease (ESRD)] had significantly lower numbers of EPCs (CXCR4/CD34+), higher MCA, and elevated serum levels of VEGF and SDF-1α (all p < 0.01). Serum VEGF level but not MCA or SDF-1α was strongly correlated with increased numbers of circulating EPCs. Multivariate analysis showed that ESRD along with lower serum albumin was independently predictive of lower numbers of circulating EPCs (p < 0.04).

CONCLUSION

Circulating EPCs were markedly reduced in CKD patients. ESRD was strongly and independently predictive of decreased numbers of circulating EPCs.

Prognostic value of renal dysfunction for the prediction of outcome versus results of computed tomographic coronary angiography

Chronic kidney disease (CKD) is associated with cardiovascular (CV) events caused by advanced atherosclerosis. Computed tomographic coronary angiography (CTA) can accurately diagnose coronary artery disease (CAD) and predict CV outcomes. The aim of the present study was to evaluate whether moderate CKD provides prognostic information for CV events in patients undergoing CTA. In total 885 patients with suspected CAD underwent CTA and were stratified to moderate CKD (85 patients) or no CKD (770 patients) based on a cut-off estimated glomerular filtration rate of 60 ml/min/1.73 m(2). After 896 days of follow-up, 42 patients developed CV events. Annualized CV event rates were 1.2% in patients with no CKD and no CAD, 2.5% in patients with moderate CKD alone, 2.5% in patients with obstructive CAD alone, and 3.7% in those with moderate CKD and obstructive CAD. Multivariate models demonstrated that moderate CKD (hazard ratio 2.39, confidence interval 1.09 to 5.21, p = 0.03) and obstructive CAD (hazard ratio 2.76, confidence interval 1.40 to 5.44, p <0.01) were independent predictors of CV events. Importantly, moderate CKD provided incremental prognostic information in addition to clinical characteristics and obstructive CAD (chi-square 49.4, p = 0.04). In conclusion, moderate CKD was associated with CV events and provided incremental prognostic information.

Management of coronary artery disease in end-stage renal disease

Despite a substantial number of patients with end-stage renal disease who have coronary artery disease, the comparative effectiveness of revascularization procedures such as coronary artery bypass grafting and percutaneous coronary intervention remain unclear. Innovations in the field of coronary artery revascularization and concomitant changes in the standard of practice have improved outcomes in general. However, meaningful clinical decision-making remains difficult because it requires clinicians to extrapolate evidence derived from studies in the general population to patients with kidney disease for whom there is limited information from intervention trials. In non-randomized studies, this high-risk population for cardiovascular morbidity and mortality appear to derive substantial benefits from coronary revascularization. However, specific treatment decisions are often made based upon individual circumstances and contexts that are not well captured in these studies. This article reviews the available evidence, and its limitations, for deciding between various revascularization strategies for patients with end-stage renal disease. Several considerations that arise while making such decisions are discussed.

Cardiovascular disease in chronic kidney disease. A clinical update from Kidney Disease: Improving Global Outcomes (KDIGO)

Cardiovascular morbidity and mortality in patients with chronic kidney disease (CKD) is high, and the presence of CKD worsens outcomes of cardiovascular disease (CVD). CKD is associated with specific risk factors. Emerging evidence indicates that the pathology and manifestation of CVD differ in the presence of CKD. During a clinical update conference convened by the Kidney Disease: Improving Global Outcomes (KDIGO), an international group of experts defined the current state of knowledge and the implications for patient care in important topic areas, including coronary artery disease and myocardial infarction, congestive heart failure, cerebrovascular disease, atrial fibrillation, peripheral arterial disease, and sudden cardiac death. Although optimal strategies for prevention, diagnosis, and management of these complications likely should be modified in the presence of CKD, the evidence base for decision making is limited. Trials targeting CVD in patients with CKD have a large potential to improve outcomes.

Atherosclerosis in CKD: differences from the general population

The prevalence of cardiovascular morbidity and mortality is higher in patients with chronic kidney disease (CKD)-especially those with end-stage renal disease-than in the general population. The contribution of atherosclerosis to cardiovascular disease in patients with CKD remains unclear. Researchers in the 1970s proposed that atherosclerosis was the main cause of cardiovascular disease in patients with CKD and that its progression, based on observations of patients on long-term dialysis, was accelerated by the uremic state. Subsequent reports, however, favor the involvement of other mechanisms, such as arteriosclerosis (characterized by vascular stiffening), vascular calcification, 'myocyte/capillary mismatch', congestive cardiomyopathy, and sudden cardiac death. Imaging and morphological studies have contributed to our understanding of the pathogenesis and progression of cardiovascular disease associated with CKD. Based on clinical and experimental findings, we hypothesize the following: the initial cardiovascular abnormalities in the CKD setting include arteriosclerosis, left ventricular diastolic dysfunction, and left ventricular hypertrophy, abnormalities which, in adult patients, are often accompanied by atherosclerosis. The prevalence of atherosclerosis increases with age and is aggravated, but not specifically induced, by CKD. The cardiovascular events associated with atherosclerosis are more often fatal in patients with CKD than in individuals without CKD.

Relationship between major adverse cardiac events and angiographic findings in dialysis patients

BACKGROUND

In dialysis patients, coronary angiography (CA) predicts major adverse coronary events (MACE) better than non-invasive tests. The aim of this study was to investigate in such patients the relationship between coronary atherosclerotic damage shown by angiography and MACE, during an average follow-up period of more than 5 years.

PATIENTS AND METHODS

Coronary angiography was performed in 63 dialysis patients (mean age 56 ± 12 years, 49 men); 37 subjects awaiting kidney transplantation had no history of cardiac disease, whereas the remaining 26 patients had clinical evidence of coronary artery disease (CAD). During a follow-up period of 62 ± 20 months (range 12-109), all the MACE were recorded. Statistical analysis was carried out by dividing the patients into two groups, those who had MACE (MACE group) and those who were free of cardiac events (FCE group). Severe CAD on CA was defined as luminal stenosis ≥ 75% in at least one vessel. Logistic regression analysis and Cox regression analysis were carried out in order to evaluate which variable was associated with MACE.

RESULTS

At the end of follow-up, 17 subjects had MACE and severe CAD was shown in the epicardial arteries of 31 patients (49%). Compared to the FCE group, the MACE group had older age (65 ± 10 vs 53 ± 11 years, P = 0.002), lower diastolic blood pressure (79 ± 7 vs 85 ± 7 mmHg, P = 0.0037), higher prevalence of CAD (82 vs 30%, P = 0.0002) and cerebrovascular disease (41 vs 15%, P = 0.0278). Coronary artery damage was higher in the MACE group than in the FCE group. Logistic and Cox regression analyses showed that age was the only variable independently associated with MACE (OR 1.109 95% CI 1.022-1.204, P = 0.0133, hazard ratio 1.066 95% CI 1.010-1.125, P = 0.02, respectively). After removal of age from the model, MACE were independently associated with haemodynamic stenosis of coronary arteries (OR 7.429 95% CI 1.829-30.173, P = 0.005, hazard ratio 5.992 95% CI 1.655-21.698, P = 0.006, respectively). Event-free survival was much better in the 37 renal transplant candidates with no history of CAD than in the 26 patients who had clinical evidence of CAD.

CONCLUSIONS

This observational study confirms that in dialysis patients coronary atherosclerotic damage shown by angiography is strongly related to MACE and that age and severe CAD are major risk factors for MACE.

Use of drug-eluting stents in patients with coronary artery disease and renal insufficiency

Renal insufficiency (RI) has been shown to be associated with increased major adverse cardiovascular events after percutaneous coronary intervention. We reviewed the impact of RI on the pathogenesis of coronary artery disease and outcomes after percutaneous coronary intervention in the form of drug-eluting stent (DES) implantation in these high-risk patients. We searched the English-language literature indexed in MEDLINE, Scopus, and EBSCO Host research databases from 1990 through January 2009, using as search terms coronary revascularization, drug-eluting stent, and renal insufficiency. Studies that assessed DES implantation in patients with various degrees of RI were selected for review. Most of the available data were extracted from observational studies, and data from randomized trials formed the basis of a post hoc analysis. The outcomes after coronary revascularization were less favorable in patients with RI than in those with normal renal function. In patients with RI, DES implantation yielded better outcomes than did use of bare-metal stents. Randomized trials are needed to define optimal treatment of these high-risk patients with coronary artery disease.

Mechanisms for increased cardiovascular disease in chronic kidney dysfunction

PURPOSE OF REVIEW

Patients with chronic kidney disease (CKD) have the highest risk for atherosclerotic cardiovascular disease (CVD). Current interventions have been insufficiently effective in lessening excess incidence and mortality from CVD in patients with CKD versus other high-risk groups. This review focuses on traditional and CKD-related risks as well as key mechanisms of macrophage foam cell formation that underlie the excess CVD in the setting of CKD.

RECENT FINDINGS

Hyperlipidemia, particularly increased low-density lipoprotein (LDL) cholesterol, is the key factor in atherogenesis in the general population, but has not been found to be the overriding risk for greater CVD in CKD, especially as renal damage progresses. Although higher incidence of CVD in CKD is not due to higher serum lipids per se, CKD is associated with abnormal lipid metabolism that is proatherogenic. CKD-related risks, including inflammation and disturbances in mineral metabolism, have been implicated. In addition, perturbations of the macrophage, a cell that is central in atherogenesis, may be important.

SUMMARY

The mechanisms underlying the heightened risk for CVD in CKD have been the focus of intense study and may relate to the combined effects of traditional and CKD-specific risks involving inflammation and lipid metabolism, especially perturbation of macrophage cholesterol homeostasis.

The association between kidney function, coronary artery disease, and clinical outcome in patients undergoing coronary angiography

To characterize the association between chronic kidney disease (CKD), mortality, severity of coronary artery disease (CAD), treatment modality of CAD, and type of coronary stents among patients undergoing coronary angiography (CAG), we retrospectively reviewed the electronic medical records of the patients who underwent CAG at Seoul National University Bundang Hospital in Korea between May 2003 and January 2006. CKD was staged using an estimated glomerular filtration rate (eGFR) from the creatinine value prior to CAG. There were 3,637 patients included. The presence of CAD was 48% in CKD stage 1, 61% in stage 2, 73% in stage 3, 87% in stage 4, and 81% in stage 5. Survival rate gradually diminished for patients with decreasing renal function. No significant differences in all-cause and cardiac mortality were observed by medical treatment, PCI or CABG, in CKD patients with an eGFR less than 60 mL/min/1.73 m(2). CKD patients with drug-eluting stents showed significantly lower all-cause mortality (5.4% vs. 13.3%) and incidence of myocardial infarction (1.7% vs. 10%) than those with bare metal stents. In conclusion, an eGFR is a strong independent prognostic marker among patients undergoing CAG and the severity of CAD increases progressively with worsening renal function.