Should we screen for coronary artery disease in asymptomatic chronic dialysis patients?

Development and Validation of Prediction Models for All-Cause Mortality and Cardiovascular Mortality in Patients on Hemodialysis: A Retrospective Cohort Study in China

Purpose

This study aimed to develop two predictive nomograms for the assessment of long-term survival status in hemodialysis (HD) patients by examining the prognostic factors for all-cause mortality and cardiovascular (CVD) event mortality.

Patients and methods

A total of 551 HD patients with an average age of over 60 were included in this study. The patients' medical records were collected from our hospital and randomly allocated to two cohorts: the training cohort (n=385) and the validation cohort (n=166). We employed multivariate Cox assessments and fine-gray proportional hazards models to explore the predictive factors for both all-cause mortality and cardiovascular event mortality risk in HD patients. Two nomograms were established based on predictive factors to forecast patients' likelihood of survival for 3, 5, and 8 years. The performance of both models was evaluated using the area under the curve (AUC), calibration plots, and decision curve analysis.

Results

The nomogram for all-cause mortality prediction included seven factors: age ≥ 60, sex (male), history of diabetes and coronary artery disease, diastolic blood pressure, total triglycerides (TG), and total cholesterol (TC). The nomogram for cardiovascular event mortality prediction included three factors: history of diabetes and coronary artery disease, and total cholesterol (TC). Both models demonstrated good discrimination, with AUC values of 0.716, 0.722 and 0.725 for all-cause mortality at 3, 5, and 8 years, respectively, and 0.702, 0.695, and 0.677 for cardiovascular event mortality, respectively. The calibration plots indicated a good agreement between the predictions and the decision curve analysis demonstrated a favorable clinical utility of the nomograms.

Conclusion

Our nomograms were well-calibrated and exhibited significant estimation efficiency, providing a valuable predictive tool to forecast prognosis in HD patients.

Hemodialysis Patients with Cardiovascular Disease Reveal Increased Tissue Na+ Deposition

BACKGROUND

The relationship between Na+ balance and cardiovascular disease (CVD) in hemodialysis (HD) patients is not yet fully understood. We hypothesized that HD patients co-diagnosed with CVD show increased tissue Na+ accumulation compared to HD patients without CVD.

METHODS

In our observational study 52 HD patients were divided into a group with (23 subjects) or without (29 subjects) a positive history of cardiovascular events. We used 23Na-Magnetic Resonance Imaging (23Na-MRI) at 3.0 Tesla to quantify Na+ content in skin and muscle of both groups directly before and after HD. Additionally, total body fluid distribution was determined by Bioimpedance Spectroscopy (BIS) and laboratory parameters were assessed.

RESULTS

Compared to HD patients without CVD, 23Na-MRI detected an increased Na+ content in skin (21.7 ± 7.3 vs. 30.2 ± 9.8 arbitrary units, a.u., p < 0.01) and muscle tissue (21.5 ± 3.6 vs 24.7 ± 6.0 a.u., p < 0.05) in patients with previous CVD events. Simultaneously measured fluid amount by BIS, including excess extracellular water (1.8 ± 1.7 vs. 2.2 ± 1.7 L, p = 0.44), was not significantly different between both groups. Tissue Na+ accumulation in HD-CVD patients was paralleled by a higher plasma concentration of the inflammation marker Interleukin-6 (5.1, IQR 5.8 vs. 8.5, IQR 7.9 pg/ml, p < 0.05).

CONCLUSION

In our cohort, HD patients with CVD showed higher tissue Na+ content than HD patients without CVD, while no difference in body water distribution could be detected between both groups. Our findings provide evidence that the history of a cardiovascular event is associated with disturbances in tissue Na+ content in HD patients.

Impaired perfusion in the myocardial microcirculation in asymptomatic patients with Stages 1-4 chronic kidney disease with intrarenal arterial lesions

BACKGROUND

Even mild renal disease is a powerful cardiovascular risk factor. However, the association between these pathophysiologic processes (especially in the early asymptomatic stage) is not known.

METHODS

We recruited 243 asymptomatic patients with Stages 1-4 chronic kidney disease (CKD) without obstructive coronary artery disease (CAD). We distinguished different degrees of severity of intrarenal arterial lesions (IALs) according to the Oxford classification. Myocardial microcirculation perfusion was measured using single-photon emission computed tomography (SPECT). Summed scores of 17 stress and rest image segments produced the summed stress score (SSS) and summed rest score (SRS), respectively. The summed difference score (SDS) was calculated as the difference between the SSS and SRS. Coronary microvascular disease (CMD) was defined as abnormal SPECT (SSS ≥4 or SDS ≥2) in the absence of obstructive CAD.

RESULTS

Participants showed a stepwise increase in CMD severity with IAL aggravation. SSS of no/mild/moderate/severe IALs was 1.64 ± 1.08, 2.56 ± 1.35, 4.42 ± 2.17 and 6.48 ± 3.52, respectively (P < 0.05 for all). SDS of no/mild/moderate/severe IALs was 1.29 ± 0.49, 1.75 ± 0.56, 3.06 ± 1.12 and 4.16 ± 1.85, respectively (P < 0.05 for all). The percentage of subclinical CMD in CKD patients with IALs was significantly higher than in those without IALs (69.57% versus 14.71%; P = 0.01). Multiple regression analysis showed that renal arteriolar hyalinization (odds ratio = 1.578, P = 0.009) was associated independently with subclinical CMD.

CONCLUSIONS

We demonstrated, for the first time, that impaired perfusion in the myocardial microcirculation in asymptomatic patients with Stages 1-4 CKD with IALs. Renal arteriolar hyalinization may be a useful marker of CMD in CKD.

Cardiovascular risk assessment and coronary artery calcification burden in asymptomatic patients in the initial years of hemodialysis

The specific tool for cardiovascular risk assessment in hemodialysis population has not yet been proposed, despite high prevalence of cardiovascular morbidity, and mortality in clinically asymptomatic patients. Coronary artery calcium score (CACS), as a reliable predictor of future cardiovascular events, might be a valuable approach. We sought to evaluate coronary artery calcification burden and its association with clinical and laboratory parameters in asymptomatic patients who recently initiated hemodialysis. The cross-sectional study included 60 asymptomatic patients receiving chronic hemodialysis for no longer than 48 months. CACS was assessed by cardiac computed tomography. Intima-media thickness (IMT) of both common carotid and femoral arteries were measured using ultrasonography. The mean total CACS was 160.50 (443). Patients' age correlated significantly with CACS (σ = 0.367; P = 0.004), carotid (σ = 0.375; P = 0.004) and femoral IMT (σ = 0.323; P = 0.013). Patients with CACS = 0 were significantly younger than patients with CACS >400: 52.4 ± 7.91 vs. 63.88 ± 8.37 years old, respectively (P = 0.034). In patients receiving dialysis for longer than 24 months CACS, femoral and carotid IMT were higher than in those dialyzed for less than 24 months; however, none has reached significance. There was a significant positive correlation between CACS and right (σ = 0.312; P = 0.018) and left (σ = 0.521; P < 0.001) femoral IMT, while not with carotid. CACS showed significant negative correlation with the serum iron (σ = -0.351; P = 0.007). Calcification burden varies significantly in asymptomatic patients in early years of dialysis. It correlates with patients' age and tends to increase with dialysis vintage. Femoral IMT might be useful for cardiovascular risk stratification in asymptomatic patients who recently initiated hemodialysis.

Cardiovascular evaluation in advanced chronic kidney disease

Patients with chronic kidney disease (CKD) display an increased cardiovascular comorbidity, which is often underdiagnosed. Thus, effective cardiovascular diagnostic testing is of particular importance for this group of patients. Data from prospective randomized trials with cardiovascular diagnostic testing in CKD patients and improved outcome are limited. Diagnostic stress testing for CKD patients requires special consideration. Guidelines recommend cardiovascular diagnostic testing for patients undergoing an evaluation before transplantation.

Silent coronary artery disease in type 2 diabetes: a narrative review on epidemiology, risk factors, and clinical studies

Silent coronary artery disease (CAD) is one of the manifestations of heart disease that particularly affects subjects with type 2 diabetes mellitus (T2DM). From a clinical point of view, silent CAD represents a constant challenge for the diabetologist, who has to decide whether a patient could or could not be screened for this disease. In the present narrative review, several aspects of silent CAD are considered: the epidemiology of the disease, the associated risk factors, and main studies conducted, in the last 20 years, especially aimed to demonstrate the usefulness of the screening of silent CAD, to improve cardiovascular outcomes in type 2 diabetes.

Cardiac Imaging for Coronary Heart Disease Risk Stratification in Chronic Kidney Disease

Chronic kidney disease (CKD), defined as dysfunction of the glomerular filtration apparatus, is an independent risk factor for the development of coronary artery disease (CAD). Patients with CKD are at a substantially higher risk of cardiovascular mortality compared with the age- and sex-adjusted general population with normal kidney function. The risk of CAD and mortality in patients with CKD is correlated with the degree of renal dysfunction including presence of microalbuminuria. A greater cardiovascular risk, albeit lower than for patients receiving dialysis, persists even after kidney transplantation. Congestive heart failure, commonly caused by CAD, also accounts for a significant portion of the cardiovascular-related events observed in CKD. The optimal strategy for the evaluation of CAD in patients with CKD, particularly before renal transplantation, remains a topic of contention spanning over several decades. Although the evaluation of coexisting cardiac disease in patients with CKD is desirable, severe renal dysfunction limits the use of radiographic and magnetic resonance contrast agents due to concerns regarding contrast-induced nephropathy and nephrogenic systemic sclerosis, respectively. In addition, many patients with CKD have extensive and premature (often medial) calcification disproportionate to the severity of obstructive CAD, thereby limiting the diagnostic value of computed tomography angiography. As such, echocardiography, non-contrast-enhanced magnetic resonance, nuclear myocardial perfusion, and metabolic imaging offer a variety of approaches to assess obstructive CAD and cardiomyopathy of advanced CKD without the need for nephrotoxic contrast agents.

[Cardiovascular diagnostic testing in advanced chronic kidney disease: which tests are useful?]

Against the background of drastically increased cardiovascular comorbidity in patients with chronic kidney disease (CKD), an effective cardiovascular diagnostic approach appears essential. However, patients with CKD are often underdiagnosed. Prospective randomized studies showing an improved outcome for cardiovascular diagnostic in patients with CKD are limited. Special attention is paid to stress diagnostics in CKD patients. Guidelines recommend cardiovascular diagnostic evaluation prior to inclusion on the transplantation waiting list.

Prognostic study of cardiac events in Japanese patients with chronic kidney disease using ECG-gated myocardial Perfusion imaging: Final 3-year report of the J-ACCESS 3 study

BACKGROUND

Myocardial perfusion imaging (MPI) is considered useful for risk stratification among patients with chronic kidney disease (CKD), without renal deterioration by contrast media.

METHODS AND RESULTS

The Japanese Assessment of Cardiac Events and Survival Study by Quantitative Gated SPECT (J-ACCESS 3) is a multicenter, prospective cohort study investigating the ability of MPI to predict cardiac events in 529 CKD patients without a definitive coronary artery disease. All patients were assessed by stress and rest MPI with 99mTc-tetrofosmin and data were analyzed using a defect scoring method and QGS software. Major cardiac events were analyzed for 3 years after registration. The mean eGFR was 29.0 ± 12.8 (mL/minute/1.73 m2). The mean summed stress/rest/difference (SSS, SRS, SDS) scores were 1.9 ± 3.8, 1.1 ± 3.0, and 0.8 ± 1.8, respectively. A total of 60 cardiac events (three cardiac deaths, six sudden deaths, five nonfatal myocardial infarctions, 46 hospitalization cases for heart failure) occurred. The event-free survival rate was lower among patients with kidney dysfunction, higher SSS, and higher CRP values. Multivariate Cox regression analysis independently associated SSS ≥8, eGFR <15 (mL/minute/1.73 m2), and CRP ≥0.3 (mg/dL) with cardiac events.

CONCLUSIONS

Together with eGFR and CRP, MPI can predict cardiac events in patients with CKD.

Risk stratification for coronary artery disease in multi-ethnic populations: Are there broader considerations for cost efficiency?

Coronary artery disease (CAD) screening and diagnosis are core cardiac specialty services. From symptoms, autopsy correlations supported reductions in coronary blood flow and dynamic epicardial and microcirculatory coronaries artery disease as etiologies. While angina remains a clinical diagnosis, most cases require correlation with a diagnostic modality. At the onset of the evidence building process much research, now factored into guidelines were conducted among population and demographics that were homogenous and often prior to newer technologies being available. Today we see a more diverse multi-ethnic population whose characteristics and risks may not consistently match the populations from which guideline evidence is derived. While it would seem very unlikely that for the majority, scientific arguments against guidelines would differ, however from a translational perspective, there will be populations who differ and importantly there are cost-efficacy questions, e.g., the most suitable first-line tests or what parameters equate to an adequate test. This article reviews non-invasive diagnosis of CAD within the context of multi-ethnic patient populations.

Syncope and Collapse Are Associated with an Increased Risk of Cardiovascular Disease and Mortality in Patients Undergoing Dialysis

Objective: This study explored the impact of syncope and collapse (SC) on cardiovascular events and mortality in patients undergoing dialysis. Methods: Patients undergoing dialysis with SC (n = 3876) were selected as the study cohort and those without SC who were propensity score-matched at a 1:1 ratio were included as controls. Major adverse cardiovascular events (MACEs), including acute coronary syndrome (ACS), arrhythmia or cardiac arrest, stroke, and overall mortality, were evaluated and compared in both cohorts. Results: The mean follow-up periods until the occurrence of ACS, arrhythmia or cardiac arrest, stroke, and overall mortality in the SC cohort were 3.51 ± 2.90, 3.43 ± 2.93, 3.74 ± 2.97, and 3.76 ± 2.98 years, respectively. Compared with the patients without SC, those with SC had higher incidence rates of ACS (30.1 vs. 24.7 events/1000 people/year), arrhythmia or cardiac arrest (6.75 vs. 3.51 events/1000 people/year), and stroke (51.6 vs. 35.7 events/1000 people/year), with higher overall mortality (127.7 vs. 77.9 deaths/1000 people/year). The SC cohort also had higher risks for ACS, arrhythmia or cardiac arrest, stroke, and overall mortality (adjusted hazard ratios: 1.28 (95% confidence interval (CI) = 1.11⁻1.46), 2.05 (95% CI = 1.50⁻2.82), 1.48 (95% CI = 1.33⁻1.66), and 1.79 (95% CI = 1.67⁻1.92), respectively) than did the non-SC cohort. Conclusion: SC was significantly associated with cardiovascular events and overall mortality in the patients on dialysis. SC may serve as a prodrome for cardiovascular comorbidities, thereby assisting clinicians in identifying high-risk patients.

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

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Long-term prognosis of end-stage renal disease patients with normal myocardial perfusion as determined by single photon emission computed tomography

BACKGROUND/AIMS

Normal myocardial perfusion is closely associated with very low rates of cardiac events and better long-term outcomes; however, little is known about its prognostic value in patients with end-stage renal disease (ESRD).

METHODS

A total of 286 incident patients underwent baseline cardiac evaluations using echocardiography and stress-rest single-photon emission computed tomography. Perfusion scans for 177 patients (61.9%) who had a summed stress score (SSS) < 4 were normal.

RESULTS

During the 4-year follow-up period, 79 cardiac events occurred. Patients with a SSS < 4 had significantly lower annual rates of cardiac events than did those with a SSS ≥ 4 (6.4% vs. 13.2%; hazard ratio, 0.54; 95% confidence interval, 0.31 to 0.94). Among patients with a SSS < 4, however, cardiac event rates significantly differed according to the presence of comorbid conditions such as old age, diabetes, history of coronary artery disease, and elevated C-reactive protein levels. In addition, the presence of left ventricular (LV) systolic dysfunction and LV hypertrophy at the start of hemodialysis strongly influenced future cardiac events.

CONCLUSIONS

In patients with ESRD, normal perfusion scans usually indicate a significantly low risk of adverse cardiac events. However, even in patients with normal perfusion scans, the cardiovascular prognosis is largely dependent on baseline inflammation levels and comorbidities.

Applying preoperative dipyridamole thallium-201 scintigraphy for preventing cardiac mortality and complications for patients with secondary hyperparathyroidism undergoing parathyroidectomy

BACKGROUND

To evaluate the value of preoperative dipyridamole thallium-201 scintigraphy for reducing cardiovascular complication in secondary hyperparathyroidism (SHPTH) patients.

METHODS

Thallium scintigraphy was arranged for all dialysis patients who underwent parathyroidectomy from Jan 2011 to July 2015. Management of defects on thallium scintigraphy included cardiac catheterization and ultrasonography. Analysis includes 30-day mortality, morbidity and the predicting factors for thallium scintigraphy defect.

RESULTS

Of 249 patients with SHPTH, 19 (7.6%) had defects on thallium scintigraphy, 15 (88%) of whom had coronary artery disease on angiography. History of acute coronary syndrome (ACS, p < 0.001), diabetes mellitus (DM, p = 0.03), male sex (p = 0.03), and higher body mass index (BMI, p = 0.001) were significant predictors of positive thallium scintigraphy results. History of ACS was the most significant predictor after adjustment in the multivariate logistic analysis (odds ratio, 22.56; 95% confidence interval, 7.02-72.53). All the patients survived the 30-day postoperative period, with minimal cardiovascular morbidity.

CONCLUSION

Preoperative dipyridamole thallium-201 scintigraphy is useful for SHPTH patients to minimized surgical mortality and morbidity.

Abdominal aortic calcification on a plain X-ray and the relation with significant coronary artery disease in asymptomatic chronic dialysis patients

Background

Coronary artery disease (CAD) is common in asymptomatic chronic dialysis patients and plays an important role in their poor survival. Early identification of these high-risk patients could improve treatment and reduce mortality. Abdominal aortic calcification (AAC) has previously been associated with CAD in autopsy studies. Since the AAC can be quantified easily using a lateral lumbar X-ray we hypothesized that the extent of AAC as assessed on a lateral lumbar X-ray might be predictive of the presence of significant CAD in dialysis patients.

Methods

All patients currently enrolled in the ICD2 trial without a history of CABG or a PCI with stent implantation were included in this study. All patients underwent CT-angiography (CTA) and a lateral X-ray of the abdomen. AAC on X-ray was quantified using a previously validated scoring system whereupon the association between AAC and the presence of significant CAD was assessed.

Results

A total of 90 patients were included in this study (71% male, 67 ± 7 years old). Forty-six patients were found to have significant CAD. AAC-score was significantly higher in patients with CAD (10.1 ± 4.9 vs 6.3 ± 4.6 (p < 0.05). Multivariate regression analysis revealed that AAC score is an independent predictor for the presence of CAD with a 1,2 fold higher risk per point increase (p < 0.01). The AAC score has a sensitivity of 85% and a specificity of 57% for the presence of significant CAD.

Conclusion

This study shows that abdominal aortic calcification as assessed on a lateral lumbar X-ray is predictive for the presence of significant coronary artery disease in asymptomatic dialysis patients. This simple, non-invasive and cheap screening method could contribute to early identification of patients eligible for further screening of CAD.

Trial registration

NTR948, registered 10-4-2007 ; ISRCTN20479861, registered 2-5-2007

Cardiovascular impact in patients undergoing maintenance hemodialysis: Clinical management considerations

Patients undergoing maintenance hemodialysis develop both structural and functional cardiovascular abnormalities. Despite improvement of dialysis technology, cardiovascular mortality of this population remains high. The pathophysiological mechanisms of these changes are complex and not well understood. It has been postulated that several non-traditional, uremic-related risk factors, especially the long-term uremic state, which may affect the cardiovascular system. There are many cardiovascular changes that occur in chronic kidney disease including left ventricular hypertrophy, myocardial fibrosis, microvascular disease, accelerated atherosclerosis and arteriosclerosis. These structural and functional changes in patients receiving chronic dialysis make them more susceptible to myocardial ischemia. Hemodialysis itself may adversely affect the cardiovascular system due to non-physiologic fluid removal, leading to hemodynamic instability and initiation of systemic inflammation. In the past decade there has been growing awareness that pathophysiological mechanisms cause cardiovascular dysfunction in patients on chronic dialysis, and there are now pharmacological and non-pharmacological therapies that may improve the poor quality of life and high mortality rate that these patients experience.

Anaemia and early phase cardiovascular events on haemodialysis

Although the mechanism of the cardio-renal anaemia syndrome (CRAS) has been elucidated in considerable detail over the past decade, cardiovascular disease (CVD) remains a leading cause of death among patients with end-stage kidney disease (ESKD) undergoing haemodialysis, and these patients' cardiovascular mortality is greater than that of the general population. Recent studies have reported that the CVD risk increases with advancing chronic kidney disease (CKD) stage. Furthermore, the incidence of cardiovascular events is highest during the first week after dialysis initiation, with increased risk in incident haemodialysis patients. This accumulated evidence demonstrates that how patients are managed during the pre-dialysis phase may have important implications on long-term outcomes in ESKD. Anaemia, a non-traditional risk factor for CVD, advances exponentially along with declining kidney function due to insufficient erythropoietin production. Anaemia causes functional abnormalities of the heart, as represented by cardiac hypertrophy, which results from increased cardiac workload induced by an increased preload. Left ventricular hypertrophy (LVH), a traditional risk factor for CVD, is especially associated with advanced CKD stage and could be a major risk factor for cardiovascular complications such as ischaemic heart disease, heart failure, and sudden cardiac death. In ESKD, anaemia develops more severely and requires a higher amount of erythropoiesis-stimulating agent (ESA) therapy before dialysis initiation. This suggests that improvement in anaemia management during the pre-dialysis phase may have a beneficial effect on cardiac hypertrophy and contribute to reducing the CVD risk after initiating haemodialysis.

Usefulness of an Upright T-Wave in Lead aVR for Predicting the Short-Term Prognosis of Incident Hemodialysis Patients: A Potential Tool for Screening High-Risk Hemodialysis Patients

BACKGROUND/AIMS

An upright T-wave in lead aVR (aVRT) has recently been reported to be associated with cardiovascular death and mortality among the general population and patients with prior cardiovascular disease (CVD). However, evidence for the predictive ability of aVRT in patients with chronic kidney disease is lacking. Therefore, a hospital-based, prospective, cohort study was conducted to evaluate the predictive ability of an upright aVRT for the short-term prognosis in incident hemodialysis patients.

METHODS

Among 208 patients who started maintenance hemodialysis, 79 with preexisting CVD (CVD cohort) and 129 with no history of CVD (non-CVD cohort), were studied. An upright and non-upright aVRT were defined as a wave with a positive deflection in amplitude of ≥0 mV and a negative deflection in amplitude of <0 mV, respectively. The endpoint was all-cause death.

RESULTS

Overall, the prevalence of an upright aVRT was 22.6% at baseline. During the mean follow-up period of 2.1 ± 1.0 years, 33 deaths occurred. Cumulative survival rates at 3 years after starting dialysis in patients with an upright and non-upright aVRT were 50.0 and 80.7%, respectively, in the CVD cohort and 92.0 and 91.3%, respectively, in the non-CVD cohort. In the CVD cohort, multivariate Cox regression analysis showed that an upright aVRT was an independent predictor of death after adjusting for confounding variables.

CONCLUSION

Among Japanese hemodialysis patients at high risk for CVD, an upright aVRT seems to be useful for predicting death.

Myocardial Ischemia Assessment in Chronic Kidney Disease: Challenges and Pitfalls

Coronary artery disease is the leading cause of mortality and morbidity in the chronic kidney disease (CKD) population and often presents with atypical symptoms. Current diagnostic investigations of myocardial ischemia in CKD lack sensitivity and specificity or may have adverse effects. We present a case vignette and explore the challenges of diagnostic myocardial stress investigation in patients with CKD.

Myocardial perfusion imaging for predicting cardiac events in Japanese patients with advanced chronic kidney disease: 1-year interim report of the J-ACCESS 3 investigation

PURPOSE

Whether myocardial perfusion imaging (MPI) can predict cardiac events in patients with advanced conservative chronic kidney disease (CKD) remains unclear.

METHODS

The present multicenter prospective cohort study aimed to clarify the ability of MPI to predict cardiac events in 529 patients with CKD and estimated glomerular filtration rates (eGFR) < 50 ml/min per 1.73(2) without a definitive diagnosis of coronary artery disease. All patients were assessed by stress-rest MPI with (99m)Tc-tetrofosmin and analyzed using summed defect scores and QGS software. Cardiac events were analyzed 1 year after registration.

RESULTS

Myocardial perfusion abnormalities defined as summed stress score (SSS) ≥4 and ≥8 were identified in 19 and 7 % of patients, respectively. At the end of the 1-year follow-up, 33 (6.2 %) cardiac events had occurred that included cardiac death, sudden death, nonfatal myocardial infarction, and hospitalization due to heart failure. The event-free rates at that time were 0.95, 0.90, and 0.81 for groups with SSS 0-3, 4-7, and ≥8, respectively (p = 0.0009). Thus, patients with abnormal SSS had a higher incidence of cardiac events. Multivariate Cox regression analysis showed that SSS significantly impacts the prediction of cardiac events independently of eGFR and left ventricular ejection fraction.

CONCLUSION

MPI would be useful to stratify patients with advanced conservative CKD who are at high risk of cardiac events without adversely affecting damaged kidneys.

CT coronary angiography is feasible for the assessment of coronary artery disease in chronic dialysis patients, despite high average calcium scores

Purpose

Significant obstructive coronary artery disease (CAD) is common in asymptomatic dialysis patients. Identifying these high risk patients is warranted and may improve the prognosis of this vulnerable patient group. Routine catheterization of incident dialysis patients has been proposed, but is considered too invasive. CT-angiography may therefore be more appropriate. However, extensive coronary calcification, often present in this patient group, might hamper adequate lumen evaluation. The objective of this study was to assess the feasibility of CT-angiography in this patient group.

Methods

For this analysis all patients currently participating in the ICD2 trial (ISRCTN20479861), with no history of PCI or CABG were included. The major epicardial vessels were evaluated on a segment basis (segment 1–3, 5–8, 11 and 13) by a team consisting of an interventional and an imaging specialist. Segments were scored as not significant, significant and not interpretable.

Results

A total of 70 dialysis patients, with a mean age of 66±8 yrs and predominantly male (70%) were included. The median calcium score was 623 [79, 1619].

Over 90% of the analyzed segments were considered interpretable. The incidence of significant CAD on CT was 43% and was associated with cardiovascular events during follow-up. The incidence of cardiovascular events after 2-years follow-up: 36% vs. 0% in patients with no significant CAD (p<0.01).

Conclusion

Despite the high calcium scores CT-angiography is feasible for the evaluation of the extent of CAD in dialysis patients. Moreover the presence of significant CAD on CT was associated with events during follow-up.

Left atrial volume index is a predictor of silent myocardial ischemia in high-risk patients with end-stage renal disease

Silent myocardial ischemia is highly prevalent in patients with end-stage renal disease (ESRD), and is associated with poor cardiovascular outcomes. However, the criteria for coronary artery disease screening remain unclear in asymptomatic patients. The goal of this study was to evaluate whether baseline echocardiographic parameters can predict myocardial ischemia in asymptomatic patients with ESRD. We investigated 259 high-risk asymptomatic patients with ESRD who underwent both echocardiography and myocardial perfusion single-photon emission computed tomography at the initiation of dialysis. We defined the presence of myocardial ischemia as a reversible or fixed perfusion defect. Silent myocardial ischemia was found in 99 (38.2 %) high-risk asymptomatic patients with ESRD at the initiation of dialysis. In patients with myocardial ischemia, left ventricular (LV) end systolic volume index, LV mass index, left atrial volume index (LAVI), and the ratio of early mitral inflow velocity to peak mitral annulus velocity were significantly higher, and LV ejection fraction was significantly lower, than those without myocardial ischemia. Multivariate analysis showed that LAVI, LV ejection fraction, and regional wall motion abnormalities were independently associated with the presence of silent myocardial ischemia. Severe (LA) enlargement was independently associated with the presence of silent myocardial ischemia (odds ratio 1.97; 95 % confidence interval 1.08-3.57; p = 0.026). LA enlargement is a potential marker for identifying patients with ESRD at high risk of silent myocardial ischemia.

Stiffness parameter β as a predictor of the 4-year all-cause mortality of chronic hemodialysis patients

BACKGROUND

There is a lack of information on stiffness parameter β, an index of arterial stiffness, in hemodialysis (HD) patients. The aim of the present study was to investigate whether stiffness parameter β is predictive of the long-term mortality of chronic HD patients.

METHODS

We measured biochemical parameters and the stiffness parameter β of 80 patients on maintenance HD therapy and followed their course for 4 years, and we enrolled 70 of these 80 patients in the study. We divided the 70 patients into tertiles according to their stiffness parameter β values, and conducted multivariate analyses to examine the impact of the tertiles on 4-year mortality.

RESULTS

Older age and the presence of diabetes mellitus were found to be independently associated with higher stiffness parameter β values. Fifteen patients (21.4 %) died and 16 (22.9 %) experienced a new cardiovascular event during the follow-up period. The results of a Kaplan-Meier analysis revealed a significantly higher risk of all-cause mortality in the HD patients with highest stiffness parameter β values (p = 0.0106). According to the ROC curve, the cut-off level that yielded maximal sensitivity and specificity for predicting all-cause mortality was 10.1, and the sensitivity and specificity using the cut-off value were 69.2 and 70.2 %, respectively.

CONCLUSION

The results of this study suggest that stiffness parameter β is a predictor of all-cause mortality in chronic HD patients.

Cardiac catheterization in the dialysis population in 2012: we know more, but much remains unknown

Chronic kidney disease is now widely accepted as an independent risk factor for coronary disease and the dialysis population may represent the highest risk subgroup. Among all dialysis patients, a cardiac cause of mortality has been estimated at 40%. In addition, prior studies have demonstrated that when cardiac catheterization is obtained in a consecutive series of asymptomatic diabetic patients on dialysis the rates of coronary disease can approach 50%. However, the ability to define the problem continues to be greater than the ability to treat or prevent it. Coronary revascularization strategies have limitations in the general population which are amplified in the dialysis population. The ability to accurately diagnose an acute coronary syndrome is more difficult, clinical outcomes have a smaller margin of benefit, and technical challenges result in higher complication rates. Recent data demonstrate an inverse relationship between glomerular filtration rate and the risk of presenting with an acute myocardial infarction rather than unstable angina suggesting that patients with CKD may have a unique pathophysiologic profile that is more prone to plaque rupture. However, these "vulnerable" plaques typically are associated with stenoses <50% prior to rupture and are thus poor targets for revascularization and perhaps best treated with medical therapy. Although the benefits of revascularization may continue to outweigh the risks in the context of acute coronary syndromes, preventive strategies would have to overcome the lower margin of benefit and higher complication rates.