Coronary angiography is the best predictor of events in renal transplant candidates compared with noninvasive testing

Angiographic evaluation of coronary artery disease in diabetic patients with and without end-stage kidney disease

The objective of the present investigation was to compare the coronary angiography results in diabetic patients with and without end-stage kidney disease (ESKD). We included prolonged diabetic patients with ESKD (93 patients) and without ESKD (control group, 126 patients). Angiography of the coronary arteries was performed on all patients. Our results revealed that the ESKD patients tended to have a higher degree of coronary artery stenosis in all parts of LAD (p = 0.001, 0.024, and 0.005), proximal and distal RCA (p = 0.013, and 0.008), and proximal and distal LCX artery (p = 0.001, 0.008) than non-ESKD patients. Furthermore, we found that the ESKD group had higher significant coronary artery stenosis in the LAD artery (60.5% vs. 39.5%, p < 0.001), RCA (60.3% vs. 39.7%, p < 0.001), LCX artery (79.5% vs. 20.5%, p < 0.001), and LMCA (84.6% vs 15.4%, p = 0.002) compared to control group. There was a greater prevalence of multiple vessels coronary artery disease (≥ two) among ESKD patients (29%), compared with the non-ESKD group (16.8%, p < 0.001). Significant coronary artery stenosis was meaningfully higher in asymptomatic diabetic ESKD patients on hemodialysis than non-ESKD diabetic patients. Coronary angiography may be beneficial in diabetic patients with ESKD regardless of whether they have ischemic symptoms with low complication rate through radial access.

Coronary Artery Disease Assessment and Cardiovascular Events in Middle-Aged Patients on Hemodialysis

OBJECTIVE

To explore whether, in younger patients on dialysis with longer life expectancy, assessment of coronary artery disease (CAD) could identify individuals at higher risk of events and revascularization might improve outcomes in selected patients contrary to what had been observed in elderly patients.

METHODS

From August 1997 to January 2019, 2265 patients with stage 5 chronic kidney disease were prospectively referred for cardiovascular assessment. For this study, we selected 1374 asymptomatic patients aged between 18 and 64 years. After clinical risk stratification and cardiac scintigraphy by single-photon emission computed tomography, 866 patients underwent coronary angiography. The primary end point was the composite incidence of nonfatal/fatal major adverse cardiovascular events during a follow-up period of 0.1 to 189.7 months (median, 26 months). The secondary end point was all-cause mortality.

RESULTS

The primary end point occurred in 327 (23.8%) patients. Clinically stratified high-risk patients had a 3-fold increased risk of the primary end point. The prevalence of abnormal findings on perfusion scans was 29.2% (n=375), and significant CAD was found in 449 (51.8%) of 866 patients who underwent coronary angiography. An abnormal finding on myocardial perfusion scan and the presence of CAD were significantly associated with a 74% and 22% increased risk of cardiovascular events, respectively. In patients undergoing percutaneous coronary intervention or coronary artery bypass grafting (n=99), there was an 18% reduction in the risk of all-cause death relative to patients receiving medical treatment (P=.03).

CONCLUSION

In this cohort of middle-aged, asymptomatic patients on dialysis, assessment of CAD identified individuals at higher risk of events, and coronary intervention was associated with reducing the risk of death in selected patients.

Standardized risk-stratified cardiac assessment and early posttransplant cardiovascular complications in kidney transplant recipients

Introduction

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in kidney transplant recipient (KTR). There is a dearth of standardized guidelines on optimal cardiovascular evaluation of transplant candidates.

Methods

This single-center cohort study aims to determine the effectiveness of our standardized risk-stratified pretransplant cardiovascular screening protocol, which includes coronary angiography (CAG), in identifying advanced CVD, the proper pretransplant management of which could lead to a reduction in the incidence of major cardiac events (MACE) in the early posttransplant period.

Results

Out of the total 776 KTR transplanted between 2017 and 2019, CAG was performed on 541 patients (69.7%), of whom 22.4% were found to have obstructive coronary artery disease (CAD). Asymptomatic obstructive CAD was observed in 70.2% of cases. In 73.6% of cases, CAG findings resulted in myocardial revascularization. MACE occurred in 5.6% (N = 44) of the 23 KTR with pretransplant CVD and 21 without pretransplant CVD. KTR with posttransplant MACE occurrence had significantly worse kidney graft function at the first year posttransplant (p = 0.00048) and worse patient survival rates (p = 0.0063) during the 3-year follow-up period compared with KTR without MACE. After adjustment, the independent significant factors for MACE were arrhythmia (HR 2.511, p = 0.02, 95% CI 1.158-5.444), pretransplant history of acute myocardial infarction (HR 0.201, p = 0.046, 95% CI 0.042-0.970), and pretransplant myocardial revascularization (HR 0.225, p = 0.045, 95% CI 0.052-0.939).

Conclusion

Asymptomatic CVD is largely prevalent in KTR. Posttransplant MACE has a negative effect on grafts and patient outcomes. Further research is needed to assess the benefits of pretransplant myocardial revascularization in asymptomatic kidney transplant candidates.

Diagnosis of cardiovascular disease in patients with chronic kidney disease

Patients with chronic kidney disease (CKD) are at high risk of cardiovascular disease (CVD) and cardiovascular death. Identifying and monitoring cardiovascular complications and hypertension is important for managing patients with CKD or kidney failure and transplant recipients. Biomarkers of myocardial ischaemia, such as troponins and electrocardiography (ECG), have limited utility for diagnosing cardiac ischaemia in patients with advanced CKD. Dobutamine stress echocardiography, myocardial perfusion scintigraphy and dipyridamole stress testing can be used to detect coronary disease in these patients. Left ventricular hypertrophy and left ventricular dysfunction can be detected and monitored using various techniques with differing complexity and cost, including ECG, echocardiography, nuclear magnetic resonance, CT and myocardial scintigraphy. Atrial fibrillation and other major arrhythmias are common in all stages of CKD, and ambulatory heart rhythm monitoring enables precise time profiling of these disorders. Screening for cerebrovascular disease is only indicated in asymptomatic patients with autosomal dominant polycystic kidney disease. Standardized blood pressure is recommended for hypertension diagnosis and treatment monitoring and can be complemented by ambulatory blood pressure monitoring. Judicious use of these diagnostic techniques may assist clinicians in detecting the whole range of cardiovascular alterations in patients with CKD and enable timely treatment of CVD in this high-risk population.

Clinical outcomes in end stage renal disease on dialysis and severe coronary artery disease: A real-world study

BACKGROUND

The optimal management of patients with end-stage renal disease (ESRD) on dialysis with severe coronary artery disease (CAD) has not been determined.

METHODS

Between 2013 and 2017, all patients with ESRD on dialysis who had left main (LM) disease, triple vessel disease (TVD) and/or severe CAD for consideration of coronary artery bypass graft (CABG) were included. Patients were divided into 3 groups based on final treatment modality: CABG, percutaneous coronary intervention (PCI), optimal medical therapy (OMT). Outcome measures include in-hospital, 180-day, 1-year and overall mortality and major adverse cardiac events (MACE).

RESULTS

In total, 418 patients were included (CABG 11.0%, PCI 65.6%, OMT 23.4%). Overall, 1-year mortality and MACE rates were 27.5% and 55.0% respectively. Patients who underwent CABG were significantly younger, more likely to have LM disease and have no prior heart failure. In this non-randomized setting, treatment modality did not impact on 1-year mortality, although the CABG group had significantly lower 1-year MACE rates (CABG 32.6%, PCI 57.3%, OMT 59.2%; CABG vs. OMT p < 0.01, CABG vs. PCI p < 0.001). Independent predictors of overall mortality include STEMI presentation (HR 2.31, 95% CI 1.38-3.86), prior heart failure (HR 1.84, 95% CI 1.22-2.75), LM disease (HR 1.71, 95% CI 1.26-2.31), NSTE-ACS presentation (HR 1.40, 95% CI 1.03-1.91) and increased age (HR 1.02, 95% CI 1.01-1.04).

CONCLUSION

Treatment decisions for patients with severe CAD with ESRD on dialysis are complex. Understanding independent predictors of mortality and MACE in specific treatment subgroups may provide valuable insights into the selection of optimal treatment options.

Diagnostic accuracy of myocardial perfusion imaging in patients evaluated for kidney transplantation: A systematic review and meta-analysis

BACKGROUND

Cardiovascular disease is the most common cause of death after kidney transplantation. Coronary artery disease (CAD) assessment is therefore mandatory in patients evaluated for transplantation. We aimed to assess the diagnostic accuracy for CAD of single-photon emission computed tomography (SPECT) compared to the standards invasive coronary angiography (ICA) and coronary computed tomography angiography (CCTA) in patients evaluated for kidney transplantation.

METHODS

We performed a systematic literature search in PubMed, EMBASE, Web of Science, OvidSP (Medline), The Cochrane Library and Google Scholar. Studies investigating the diagnostic accuracy of myocardial perfusion imaging (MPI) SPECT in patients evaluated for kidney transplantation were retrieved. After a risk of bias assessment using QUADAS-2, a meta-analysis was conducted.

RESULTS

Out of 1459 records, 13 MPI SPECT studies were included in the meta-analysis with a total of 1245 MPI SPECT scans. There were no studies available with CCTA as reference. Pooled sensitivity of MPI SPECT for CAD was 0.66 (95% CI 0.53 to 0.77), pooled specificity was 0.75 (95% CI 0.63 to 0.84) and the area under the curve (AUC) was 0.76. Positive likelihood ratio was 2.50 (95% CI 1.78 to 3.51) and negative likelihood ratio was 0.41 (95% CI 0.28 to 0.61). Pooled positive predictive value was 64.9% and pooled negative predictive value was 74.1%. Significant heterogeneity existed across the included studies.

CONCLUSIONS

MPI SPECT had a moderate diagnostic accuracy in patients evaluated for kidney transplantation, with a high rate of false-negative findings. The use of an anatomical gold standard against a functional imaging test in the included studies is however suboptimal.

Is Exclusion of Coronary Artery Disease in the Kidney Allocation System Preventing Optimal Longevity Matching?

BACKGROUND

Coronary artery disease (CAD) in a kidney transplant candidate is an important predictor of posttransplant mortality. It is not known how the exclusion of CAD in the kidney allocation system has impacted its goal of longevity matching.

METHODS

This is an observational study on adult deceased donor kidney transplant alone recipients between December 4, 2014, and December 31, 2018, with Medicare fee for service (FFS) insurance. Patients were categorized on the basis of Kidney Donor Profile Index (KDPI), Estimated Posttransplant Survival (EPTS), and CAD. Outcomes studied were mortality, death with a functioning graft, overall graft loss, and death-censored graft loss.

RESULTS

Among 21 151 patients with Medicare FFS coverage for >1 y before transplant, there were 2869 and 18 282 patients with and without CAD, respectively. On Kaplan-Meier analysis, there was higher risk of mortality, death with a functioning graft, overall graft loss, and death-censored graft loss with CAD ( P < 0.05 for all). Mortality was higher for CAD group within each category of KDPI and among patients with Estimated Posttransplant Survival 0% to 20% receiving kidneys with KDPI <20% ( P < 0.001 for all). On Cox multivariate analysis, the hazard ratios (HRs) of mortality and graft loss were higher with CAD diagnosis without intervention (HR 1.38 [1.25-1.52] and 1.29 [1.18-1.4]), CAD with stents (HR 2.76 [1.68-4.53] and 2.36 [1.46-3.81]), and CAD with bypass surgery (HR 1.56 [1.29-1.89] and 1.39 [1.17-1.65]). Posttransplant CAD events were higher in patients with preexisting CAD ( P < 0.001).

CONCLUSIONS

The exclusion of a candidate's history of CAD in the kidney allocation system adversely impacts its goal of optimal longevity matching.

Cardiac Imaging and Management of Cardiac Disease in Asymptomatic Renal Transplant Candidates: A Current Update

Given the high cardiovascular risk accompanying end-stage kidney disease, it would be of paramount importance for the clinical nephrologist to know which screening method(s) identify high-risk patients and whether screening asymptomatic transplant candidates effectively reduces cardiovascular risk in the perioperative setting as well as in the longer term. Within this review, key studies concerning the above questions are reported and critically analyzed. The lack of unified screening criteria and of a prognostically sufficient screening cardiovascular effect for renal transplant candidates sets the foundation for a personalized patient approach in the near future and highlights the need for well-designed studies to produce robust evidence which will address the above questions.

The prognostic value of pre-operative coronary evaluation in kidney transplanted patients

Aims

Non-invasive coronary assessment using single-photon emission computerized tomography (SPECT) testing for potential cardiac ischemia is an essential part of the evaluation of kidney transplant candidates. We aimed to examine the prognostic value of preoperative SPECT test results in kidney transplanted patients.

Methods and results

We retrospectively analyzed the pre-surgical nuclear SPECT test results in a registry of kidney transplanted patients. Follow-up at 1 month and 1 year recorded major adverse cardiac events (MACE) including non-fatal myocardial infarction, all-cause mortality and hospitalization due to cardiovascular disease following the renal transplantation. Of 577 patients available for analysis, 408 (70.9%) patients underwent nuclear SPECT test pre-transplant and 83 (20.3%) had abnormal results with either evidence of ischemia or infarct. A significantly higher incidence of post-operative MACE at 1 month was evident among patients with abnormal SPECT test compared to patients with no evidence of ischemia (10.8 vs. 4.3% respectively; P = 0.019). Differences were mostly derived from significantly increased rates of myocardial infarction events (8.4 vs. 1.8%; P = 0.002). Yet, MACE rate was not statistically different at 1 year (20.5 vs. 13.1%; P = 0.88). Importantly, the prognostic impact of an abnormal SPECT was significantly attenuated for all outcomes following multivariable adjusting for conventional cardiovascular risk factors and coronary revascularization.

Conclusion

Pre-surgical cardiac risk assessment of kidney transplant candidates with nuclear SPECT test was found to be predictive of post-operative MACE, yet apparently, its prognostic value was significantly attenuated when adjusted for cardiac risk factors.

Cardiac imaging for the assessment of patients being evaluated for kidney transplantation

Cardiac risk assessment before kidney transplantation has become widely accepted. However, the optimal patient selection and screening tool for cardiac assessment remain controversial. Clinicians face several challenges in this process, including the ever-growing pre-transplant population, aging transplant candidates, increasing prevalence of coronary artery disease, and scarcity of donor organs. Optimizing the cardiovascular risk profile in kidney transplant candidates is necessary to better appropriate limited donor organs and improve patient outcomes. Increasing waiting times from the initial evaluation for transplant candidacy to the actual transplant raises questions regarding re-testing and re-stratification of risk. In this review, we summarize and discuss the current literature on cardiac evaluation prior to kidney transplantation. We also propose simple evidence-based evaluation algorithms for initial and follow-up CAD surveillance in patients being wait-listed for kidney transplantation.

Cardiovascular risk stratification in the noncardiac solid organ transplant candidate

PURPOSE OF REVIEW

Solid organ transplantation (SOT) has become a widely accepted therapy for end-stage disease across the spectrum of thoracic and abdominal organs. With contemporary advances in medical and surgical therapies in transplantation, candidates for SOT are increasingly older with a larger burden of comorbidities, including cardiovascular disease (CVD). CVD, in particular, is a leading cause of morbidity and mortality in SOT candidates with end-stage disease of noncardiac organs [1].

RECENT FINDINGS

Identification of coronary artery disease (CAD), heart failure, and valvular disease are important in noncardiac SOT to ensure both appropriate peri-transplant management and equitable organ allocation. Although the American College of Cardiology (ACC) and the American Heart Association (AHA) have published guidelines and recommendations for the perioperative cardiovascular evaluation of patients undergoing noncardiac surgery, the implications of both symptomatic and asymptomatic CVD differ in patients with end-stage organ failure being considered for SOT when compared to the general population.

SUMMARY

Herein, we review the epidemiology, diagnosis, and evidence for the management of CVD in kidney and liver transplantation, combining current guidelines from the 2012 ACC/AHA scientific statement on cardiac disease evaluation in SOT with more contemporary evidenced-based algorithms.

Impact of cardiovascular risk stratification strategies in kidney transplantation over time

BACKGROUND

Kidney transplant recipients exhibit a dramatically increased cardiovascular (CV) risk. In 2007, Austrian centres implemented a consensus of comprehensive CV screening programme prior to kidney transplantation (KT). The consensus placed a particular emphasis on screening for coronary artery disease (CAD) with cardiac computed tomography (CT) or coronary angiography (CAG) in patients with diabetes mellitus, known CAD or those having multiple conventional CV risk factors. Here, we investigate if this affected risk stratification and post-transplant CV outcomes.

METHODS

In a retrospective chart review, we evaluated 551 KTs performed from 2003 to 2015 in our centre. Patients were categorized into three groups: KT before (2003-07), directly after (2008-11) and 5 years after (2012-15) implementation of the consensus. We analysed clinical characteristics, the rate of cardiac CTs and CAGs prior to KT as well as major adverse cardiac events (MACEs) during a 2-year follow-up after KT.

RESULTS

The three study groups showed a homogeneous distribution of comorbidities and age. Significantly more cardiac CTs (13.6% versus 10.2% versus 44.8%; P = 0.002) and CAGs (39.6% versus 43.9% versus 56.2%; P = 0.003) were performed after the consensus. Coronary interventions were performed during 42 out of 260 CAGs (16.2%), the cumulative 2-year MACE incidence was 8.7%. Regarding MACE occurrence, no significant difference between the three groups was found.

CONCLUSION

CV risk stratification has become more rigorous and invasive after the implementation of the consensus; however, this was not associated with an improvement in CV outcome.

Non-invasive cardiac stress studies may not offer significant benefit in pre-kidney transplant evaluation: A retrospective cohort study

Background

Screening with cardiac non-invasive stress studies (NISS) prior to listing for kidney transplantation can help in identifying treatable coronary disease and is considered an integral part of pre-kidney transplant evaluation. However, few studies assessed their effectiveness in all patients evaluated for transplantation in clinical practice. To evaluate the role of NISS in pre-kidney transplant evaluation we analyzed their impact prior to waitlisting in 1053 adult CKD-5 patients consecutively evaluated in Greater Manchester, UK during a 6-year period.

Methods

918 waitlisted patients were grouped based on presence or absence of Diabetes or Cardio-Vascular Disease (CVD): Group-1 (255 DM-/CVD-/NISS-), Group-2 (368 DM-/CVD-/NISS+) and Group-3 (295 with DM or CVD).

Results

Group-2 patients had longer ‘time-to-listing’ (5.5months in Group-1 vs 6.9months in ‘Normal-NISS’ vs 9.9months in ‘Abnormal-NISS’, p<0.01) but none with ‘Abnormal-NISS’ needed coronary revascularization before listing. NISS was followed by revascularization in 8 Group-3 patients (3%). In multi-variate analyses, there was no association of NISS on death or MACE in listed patients. During follow up, Transplantation was the most significant factor associated with improved outcomes in all subgroups (HR:0.97, p<0.001). 135 patients were considered unsuitable for waitlisting, with NISS influencing management in 11 of these patients (8%).

Conclusions

Pre-kidney transplant evaluation with NISS influenced clinical management in 19 of 1053 (2%) patients. Screening with NISS added limited benefit but contributes to significant delays in listing and adding resource implications. Further studies are needed to assess clinical and cost effectiveness of NISS in pretransplant evaluation to optimize outcomes and resources.

Outcomes of Surgical Coronary Revascularization Performed Before Solid Abdominal Organ Transplants

BACKGROUND

Cardiac risk stratification and coronary angiography are routinely performed as part of kidney and liver transplant candidacy evaluation. There are limited data on the outcomes of surgical coronary revascularization in this patient population. This study investigated outcomes in patients with end- stage renal or hepatic disease who were undergoing coronary artery bypass grafting (CABG) to attain kidney or liver transplant candidacy.

METHODS

This study was a retrospective analysis of all patients who underwent isolated CABG at our institution, Indiana University School of Medicine (Indianapolis, IN), between 2010 and 2016. Patients were divided into 2 cohorts: pretransplant (those undergoing surgery to attain renal or hepatic transplant candidacy) and nontransplant (all others). Baseline characteristics and postoperative outcomes were compared between the groups.

RESULTS

A total of 1801 patients were included: 28 in the pretransplant group (n = 22, kidney; n = 7, liver) and 1773 in the nontransplant group. Major adverse postoperative outcomes were significantly greater in the pretransplant group compared with the nontransplant group: 30-day mortality (14.3% vs 2.8%; P = .009), neurologic events (17.9% vs 4.8%; P = .011), reintubation (21.4% vs 5.8%; P = .005), and total postoperative ventilation (5.2 hours vs 5.0 hours; P = .0124). The 1- and 5-year mortality in the pretransplant group was 17.9% and 53.6%, respectively. Of the pretransplant cohort, 3 patients (10.7%) underwent organ transplantation (all kidney) at a mean 436 days after CABG. No patients underwent liver transplantation.

CONCLUSIONS

Outcomes after CABG in pre-kidney transplant and pre-liver transplant patients are poor. Despite surgical revascularization, most patients do not ultimately undergo organ transplantation. Revascularization strategies and optimal management in this high-risk population warrant further study.

Pre-Liver Transplant Cardiac Catheterization Is Associated With Low Rate of Myocardial Infarction and Cardiac Mortality

BACKGROUND AND AIMS

A study at Indiana University demonstrated a reduction in myocardial infarction (MI) incidence with increased frequency of cardiac catheterization (CATH) in liver transplant (LT) candidates. A strict protocol for performing CATH based upon predefined risk factors, rather than noninvasive testing alone, was applied to a subgroup (2009-2010) from that study. CATH was followed by percutaneous coronary intervention (PCI) in cases of significant coronary artery disease (CAD; ≥50% stenosis). The current study applies this screening protocol to a larger cohort (2010-2016) to assess post-LT clinical outcomes.

APPROACH AND RESULTS

Among 811 LT patients, 766 underwent stress testing (94%) and 559 underwent CATH (69%), of whom 10% had CAD requiring PCI. The sensitivity of stress echocardiography in detecting significant CAD was 37%. Predictors of PCI included increasing age, male gender, and personal history of CAD (P < 0.05 for all). Compared to patients who had no CATH, patients who underwent CATH had higher mortality (P = 0.07), and the hazard rates (HR) for mortality increased with CAD severity (normal CATH, HR, 1.35; 95% confidence interval [CI], 0.79-2.33; P = 0.298; nonobstructive CAD, HR, 1.53; 95% CI, 0.84-2.77; P = 0.161; and significant CAD, HR, 1.96; 95% CI, 0.93-4.15; P = 0.080). Post-LT outcomes were compared to the 2009-2010 subgroup from the previous study and showed similar 1-year overall mortality (8% and 6%, P = 0.48), 1-year MI incidence (<1% and <1%, P = 0.8), and MI deaths as a portion of all deaths (3% and 9%, P = 0.35).

CONCLUSIONS

Stress echocardiography alone is not reliable in screening LT patients for CAD. Aggressive CAD screening with CATH is associated with low rate of MI and cardiac mortality and validates the previously published protocol when extrapolated over a larger sample and longer follow-up period.

Cardiovascular Risk Assessment in Renal and Liver Transplant Candidates: A Multidisciplinary Institutional Standardized Approach

In the modern era, renal and liver transplant candidates present with a greater medical complexity driven in part by a higher prevalence of cardiovascular conditions, including coronary artery disease, valvular heart disease, and cardiomyopathies. In fact, cardiovascular disease is the most common cause of death after kidney transplantation worldwide. Similarly, an increase in the number of patients being listed with end-stage liver disease from nonalcoholic steatohepatitis and a rising model for end-stage liver disease scores at the time of liver transplant in the United States parallel an increasing cardiovascular disease risk profile for liver transplant candidates. A large degree of variation exists among clinical practice guidelines and transplant center practice patterns regarding patient selection for routine cardiac testing and the choice of testing modalities. Here, we review the clinical practice guidelines established at our center by a multidisciplinary group, including transplant nephrology, hepatology, and surgery, as well as general and interventional cardiology, with the goal of improving patient selection and reducing adverse cardiac events posttransplant.

Predictors of postoperative cardiovascular complications up to 3 months after kidney transplantation

Background

Renal transplant patients have a high peri-operative risk for cardiovascular events. Pre-operative screening for cardiac ischaemia might lower this risk, but there are no specific guidelines.

Methods

We conducted a chart review for all renal transplants performed between January 2010 and December 2013. We collected data about patient characteristics, pre-operative cardiac evaluation before referral, diagnostic tests and interventions. Logistic regression analyses were then applied to relate these factors to the composite endpoint of cardiac death, myocardial infarction, coronary revascularisation or admission for heart failure within 3 months after transplantation.

Results

A total of 770 kidney transplants were performed in 751 patients. In 750 cases (97%) a referral to the cardiologist was made. Non-invasive ischaemia detection by myocardial perfusion scintigraphy, exercise stress test or dobutamine stress echocardiography was carried out in 631 cases (82%). Coronary angiography was performed in 85 cases, which revealed significant coronary artery disease in 19 cases. Prophylactic revascularisation was done in 7 cases. The incidence of the study endpoint was 8.6%. In multivariable regression analysis, age at transplantation, pre-transplant myocardial infarction or heart failure, post-operative decrease in haemoglobin and positive non-invasive ischaemia testing were significantly associated with the study endpoint. However, when analysed separately, none of the different non-invasive ischaemia detection modalities were related to the study endpoint.

Conclusion

Especially those renal transplant candidates with a cardiac history carry a high risk for a cardiovascular event post-transplantation. Uniformity in cardiac screening of renal transplant candidates and better pre-operative preparation might lower this post-operative risk. Besides, post-transplant anaemia should be prevented.

Assessing cardiovascular risk in the prerenal transplant population: Comparison of myocardial perfusion imaging and coronary angiography with risk factor stratification

INTRODUCTION

Patients with end-stage renal disease (ESRD) have a higher incidence of coronary artery disease (CAD). Hence, it is crucial to evaluate CAD before renal transplantation. This study compares the utility of pharmacologic single-photon emission computed-tomography (SPECT) imaging directly to coronary angiography for diagnosis of CAD with correlation to cardiovascular risk factors.

METHOD

Retrospective review of asymptomatic renal failure patients who underwent both SPECT and coronary angiography to identify obstructive CAD between the years 2008-2016. Ninety-four ESRD subjects were evaluated.

RESULTS

Myocardial perfusion SPECT study found, when compared to coronary angiography demonstrated for CAD, the sensitivity of 93.3% with a specificity of 73.4%. Importantly, the negative predictive value for coronary artery disease was 96%. With seven or more cardiac risk factors, 66.7% of patients had obstructive coronary artery disease. Among all the risk factors examined, patients with a previous history of coronary artery disease had a 68% risk of obstructive coronary artery disease.

CONCLUSION

Comparing myocardial perfusion imaging SPECT findings with coronary angiography in patients with ESRD, a sensitivity of 93.3% and a specificity of 73% were observed. Of all the risk factors examined, patient with the previous history of CAD was the single most significant risk factor for CAD in 68% of cases.

The assessment of coronary artery disease in patients with end-stage renal disease

Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality among patients with end-stage renal disease (ESRD). Clustering of traditional atherosclerotic and non-traditional risk factors drive the excess rates of coronary and non-coronary CVD in patients with ESRD. Coronary artery disease (CAD) is a key disease process, present in ∼50% of the haemodialysis population ≥65 years of age. Patients with ESRD are more likely to be asymptomatic, posing a challenge to the correct identification of CAD, which is essential for appropriate risk stratification and management. Given the lack of randomized clinical trial evidence in this population, current practice is informed by observational data with a significant potential for bias. For this reason, the most appropriate approach to the investigation of CAD is the subject of considerable discussion, with practice patterns largely varying between different centres. Traditional imaging modalities are limited in their diagnostic accuracy and prognostic value for cardiac events and survival in patients with ESRD, demonstrated by the large number of adverse cardiac outcomes among patients with negative test results. This review focuses on the current understanding of CAD screening in the ESRD population, discussing the available evidence for the use of various imaging techniques to refine risk prediction, with an emphasis on their strengths and limitations.

Cardiac risk assessment for end-stage renal disease patients on the renal transplant waiting list

Cardiovascular disease is a leading cause of morbidity and mortality and is becoming more prevalent as the population ages and risk factors increase. This is most apparent in the end-stage renal disease (ESRD) patient population. In part, this is due to cofactors such as diabetes and hypertension commonly predisposing to progressive renal disease, as well as being a direct consequence of having renal failure. Of all major organ failures, kidney failure is the most likely to be managed chronically using renal replacement therapy and, ultimately, transplant. However, lack of transplant organs and a large renal failure cohort means waiting lists are often quite long and may extend to 5-10 years. Due to the cardiac risk factors inherent in patients awaiting transplant, many succumb to cardiac issues while waiting and present an increased per-procedural cardiac risk that extends into the post-transplant period. We aim to review the epidemiology of coronary artery disease in this population and the etiology as it relates to ESRD and its associated co-factors. We also will review the current approaches, recommendations and evidence for management of these patients as it relates to transplant waiting lists before and after the surgery. Recommendations on how to best manage patients in this cohort revolve around the available evidence and are best customized to the institution and the structure of the program. It is not clear whether the revascularization of patients without symptoms and with a good functional status yields any improvement in outcomes. Therefore, each individual case should be considered based on the risk factors, symptoms and functional status, and approached as part of a multi-disciplinary assessment program.

Cardiovascular risk reduction with periodontal treatment in patients on the waiting list for renal transplantation

BACKGROUND

Cardiovascular mortality is increased in chronic kidney disease, a condition with a high prevalence of periodontal disease. Whether periodontitis treatment improves prognosis is unknown.

METHODS

The effect of periodontal treatment on the incidence of cardiovascular events and death in 206 waitlist hemodialysis subjects was compared with that in 203 historical controls who did not undergo treatment. Patients were followed up for 24 months or until death or transplantation.

RESULTS

The prevalence of moderate/severe periodontitis was 74%. Coronary artery disease correlated with the severity of periodontal disease (P = .02). Survival free of cardiovascular events (94% vs 83%, log-rank 0.009), coronary events (97% vs 89%, log-rank = 0.009), and cardiovascular death (96% vs 87%, log-rank = 0.037) was higher in the evaluated group. Death by any cause did not differ between groups. Multivariate analysis showed that treatment was associated with reduction in cardiovascular events (HR 0.43; 95% CI 0.22-0.87), coronary events (HR 0.31; 95% CI 0.12-0.83), and cardiovascular deaths (HR 0.43; 95% CI 0.19-0.98).

CONCLUSION

Periodontal treatment reduced the 24-month incidence of cardiovascular events and cardiovascular death, suggesting that periodontal treatment may improve cardiovascular outcomes. We suggest that periodontal screening and eventual treatment may be considered in patients with advanced renal disease.

Pros and Cons of Aspirin Prophylaxis for Prevention of Cardiovascular Events in Kidney Transplantation and Review of Evidence

Kidney transplant recipients have traditional and nontraditional risk factors which can lead to coronary artery disease and sudden death with a functional graft loss. Aspirin has been used traditionally for prevention of cardiovascular and cerebrovascular accidents. It has beneficial effects in secondary prevention of cardiovascular events in general population. Its use for primary prophylaxis is still disputed. Bleeding and theoretical risk of nephrotoxicity are the major concerns about its use. The data on aspirin in kidney transplant population is sparse. This review will focus on various pros and cons of aspirin use for prevention of cardiovascular events in kidney transplant recipients and a way forward.

Risk Stratification and Treatment of Coronary Disease in Chronic Kidney Disease and End-Stage Kidney Disease

Patients with advanced chronic kidney disease have an enormous burden of cardiovascular morbidity and mortality, but, paradoxically, their representation in randomized trials for the evaluation and management of coronary artery disease has been limited. Clinicians therefore are faced with the conundrum of synergizing evidence from observational studies, expert opinion, and extrapolation from the general population to provide care to this complex and clinically distinct patient population. In this review, we address clinical risk stratification of patients with chronic kidney disease and end-stage kidney disease using traditional cardiovascular risk factors, noninvasive functional and structural cardiac imaging, invasive coronary angiography, and cardiovascular biomarkers. We highlight the unique characteristics of this population, including the high competing risk of all-cause mortality relative to the risk of major adverse cardiac events, likely owing to important contributions from nonatherosclerotic mechanisms. We further discuss the management of coronary artery disease in patients with chronic kidney disease and end-stage kidney disease, including evidence pertaining to medical management, coronary revascularization with percutaneous coronary intervention, and coronary artery bypass grafting. Our discussion includes considerations of drug-eluting versus bare metal stents for percutaneous coronary intervention and off-pump versus on-pump coronary artery bypass graft surgery. Finally, we address currently ongoing randomized trials, from which clinicians are optimistic about receiving guidance regarding the best strategies to incorporate into their practice for the evaluation and management of coronary artery disease in this high-risk population.

Screening coronary angiography in patients with long-standing diabetes mellitus undergoing kidney transplant evaluation

BACKGROUND

The utility of coronary angiography in patients with diabetes mellitus undergoing kidney transplant evaluation is unclear. Predictors of critical angiography lesions in these patients will aid in appropriate use of angiography.

METHODS

Single-center study of 80 patients with ≥15 years of diabetes mellitus who underwent a screening coronary angiography despite a negative cardiac stress test. Risk factors for needing coronary intervention (CI) (percutaneous or bypass grafting) were analyzed.

RESULTS

Eighteen patients (23%) had a ≥70% occlusion in one or more major coronary vessel(s), with right coronary artery being the most commonly involved (71%). Fifteen patients (19%) underwent coronary intervention: ten percutaneously and five with bypass surgery. Risk factors for needing CI were not being on statin (OR 3.54, P = 0.047) and history of stroke or peripheral vascular disease (PVD; OR 3.5, P = 0.034). A model that included statin use, stroke/PVD history, and glycosylated hemoglobin had a receiver operating characteristic curve area under the curve of 0.8 to predict CI.

CONCLUSION

Despite a negative stress test, the prevalence of critical coronary lesions was high among kidney transplant candidates with long-standing diabetes. Risk factors for needing coronary intervention were absence of statin use and a history of stroke or peripheral vascular disease.

Evaluation of a protocol for coronary artery disease investigation in asymptomatic elderly hemodialysis patients

BACKGROUND

Coronary artery disease (CAD) is prevalent in older patients on dialysis, but the prognostic relevance of coronary assessment in asymptomatic subjects remains undefined. We tested the usefulness of a protocol, based on clinical, invasive, and noninvasive coronary assessment, by answering these questions: Could selecting asymptomatic patients for coronary invasive assessment identify those at higher risk of events? Is CAD associated with a worse prognosis?

METHODS

A retrospective study including 276 asymptomatic patients at least 65 years old on the waiting list, prospectively evaluated for CAD and followed up until death or renal transplantation, were classified into two groups: 1) low-risk patients who did not undergo coronary angiography (n=63) and 2) patients who did undergo angiography (n=213). The latter group was reclassified into patients with significant CAD or normal angiograms/nonsignificant CAD.

RESULTS

CAD (≥70% stenosis) occurred in 124 subjects (58%). The incidence of death by any cause, coronary death, and major cardiovascular (CV) events were similar in patients selected or not for angiography and in those with or without significant CAD. Myocardial revascularization (surgical/percutaneous) was performed in only 21/276 patients (7.6%) and did not result in a reduction in mortality.

CONCLUSION

In older patients on renal replacement therapy, the prevalence of CAD was high, but coronary investigation was not useful as a risk stratification tool and also resulted in a rather small proportion of patients eligible for intervention. Therefore, in the elderly, coronary investigation should not be considered routine in asymptomatic patients.

Coronary Angiography Profile at the Time of Hemodialysis Initiation in End-Stage Renal Disease Population: A Retrospective Analysis

Cardiovascular disease is associated with increased mortality in dialysis population. However, there are very few studies that assessed the prevalence of coronary artery disease (CAD) at the time of initiation of hemodialysis (HD). The present study was aimed to assess the prevalence of CAD in end-stage renal disease (ESRD) patients at the time of initiation of HD and the risk factors for CAD in this population. This was a single-center retrospective study and included ESRD patients who underwent coronary angiography (CAG) at the time of initiation of HD. Inclusion criteria were age >18 years and those who were subjected to CAG within 2 weeks of initiation of HD. According to the findings on CAG, patients were divided into no CAD and CAD groups. CAD was diagnosed if there was >50% stenosis of vessel. Clinical and laboratory parameters between these two groups were analyzed. Ninety-seven patients were included in the study based on the inclusion criteria. Forty-four (45%) patients were diagnosed with CAD. Patients who had CAD were younger compared to no CAD group (50.7 + 10 vs. 55.8 + 9.3 years; P = 0.01). Majority of them were males. Diabetic nephropathy (DN) was associated with increased risk of CAD (60% vs. 40%, P = 0.007). History of smoking, high high-sensitivity C-reactive protein (hs-CRP), low total cholesterol, and low high-density lipoprotein (HDL) were associated with significantly increased risk of CAD. Gender, symptoms of CAD, serum low-density lipoprotein (LDL), very LDL, and triglycerides were not associated with increased risk of CAD. Neither calcium (Ca), phosphorus (PO₄), nor Ca × PO₄products were associated with an increased risk of CAD. Resting electrocardiogram abnormalities had no significance in predicting CAD (32% in CAD and 19% in no CAD group). Echocardiography showed regional wall motion abnormalities/global hypokinesia in 18% patients of CAD group and 3.8% patients of no CAD group (P = 0.03). Single-, double-, and triple-vessel disease was documented in 17 (38%), 13 (29.5%), and 14 (32.5%) patients, respectively, and the most common vessel involved was the left anterior descending artery. At the initiation of HD in ESRD patients, CAD was seen in almost half of the patients. DN was a significant risk factor for CAD. Other risk factors for CAD include smoking, low cholesterol, low HDL, and high hs-CRP levels.

Revascularization versus Medical Management of Coronary Artery Disease in Prerenal Transplant Patients: A Meta-Analysis

Introduction

End-stage renal disease requiring renal transplantation comprises a growing patient population at risk for cardiovascular disease (CVD) morbidity and mortality in large part due to accelerated atherosclerosis. Consequently, these patients are at even higher risk of major surgical CVD mortality. A paucity of research has addressed the posttransplantation CVD outcomes related to different treatment strategies in this patient population and therefore, there are no specific preoperative guidelines regarding management of coronary artery disease in this high-risk population undergoing renal transplantation.

Objective

Through meta-analysis we compare coronary revascularization to medical management prior to renal transplantation in patients who are found to have significant obstructive coronary artery disease.

Results

A total of 6 studies were deemed suitable out of 777 articles reviewed. This included 260 patients who received medical management and 338 who received coronary revascularization. There were 36 events in the revascularization and 57 events in the medical management group. One study only reported hazard ratios but no CVD outcomes. Comprehensive Meta-Analysis software was used to calculate pooled odds ratio with 95% confidence intervals (CI) for the fixed effects. The data is presented as forest plots. The pooled odds ratio with 95% CI for the fixed effects was 1.415 (95% CI 0.885–2.263), p = 0.147, indicating that there is no difference in CVD outcomes between pretransplant treatment strategy. This observation suggests that the CVD outcomes posttransplantation are not affected when optimal medical therapy is used instead of coronary revascularization.

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.

Coronary Calcium Score May Replace Cardiovascular Risk Factors as Primary Risk Stratification Tool Before Kidney Transplantation

BACKGROUND

Cardiac evaluation before kidney transplantation is recommended, but no unequivocal screening strategy has yet been identified. We investigated if coronary artery calcium score (CACS) can replace cardiovascular risk factor assessment in selection of kidney transplantation candidates for cardiac evaluation and the choice of noninvasive modality for diagnosing obstructive coronary artery disease (CAD).

METHODS

We conducted a prospective study of 167 patients referred for pretransplantation cardiac evaluation. Patients underwent risk factor assessment, CACS, coronary computed tomography angiography (CCTA), single-photon emission computed tomography (SPECT), and invasive coronary angiography. In total, 138 patients completed all diagnostic tests.

RESULTS

In patients with CAD (22%), the number of risk factors and CACS score were higher than that in patients without CAD. The accuracy evaluated by the receiver-operating characteristic curve was higher for CACS than for risk factors, 0.85 versus 0.71 (P = 0.01). Adding CACS to the risk factor increased correct categorical net reclassification (0.58, P < 0.0001). Combining risk factors (≥3) with SPECT to identify patients with obstructive CAD resulted in less sensitivity (47% vs 80%) and higher specificity (94% vs 74%), compared with CCTA. In patients with low CACS (<400), SPECT had a lower sensitivity than CCTA (60% versus 80%) but the same specificity (80%). In patients with high CACS (≥400), SPECT had lower sensitivity than CCTA (50% vs 100%) and higher specificity (88% vs 8%).

CONCLUSIONS

In kidney transplantation candidates, CACS outperformed risk factor assessment for predicting obstructive CAD and is a better tool for selecting patients and guiding the choice of noninvasive diagnostic modality in CAD.

Cardiac Imaging in Chronic Kidney Disease Patients

Cardiovascular disease is highly prevalent and it is associated with high morbidity and mortality rates in patients with chronic kidney disease (CKD). The implementation of various imaging modalities may help to risk stratify these patients with a potential ease on the burden of complications and the rising costs of care. In this article we review some of the modern imaging techniques to diagnose cardiac disease in patients affected by CKD.

Stress SPECT Myocardial Perfusion Imaging in End-Stage Renal Disease

PURPOSE OF REVIEW

Patients with end-stage renal disease (ESRD) have an increased risk of cardiovascular morbidity and mortality. Cardiac risk assessment, though challenging, is critical in these high-risk patients, particularly in the pre-transplant population. In this review, we discuss the burden of coronary artery disease in the ESRD population and review the literature on the diagnostic and prognostic performance, clinical value, and future directions of single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in ESRD patients.

RECENT FINDINGS

Stress myocardial perfusion imaging provides incremental prognostic value to clinical data. The AHA/ACCF consensus statement on the cardiac assessment of kidney transplant candidates provides some guidance on the selection of asymptomatic patients for further non-invasive risk stratification. Additionally, the novel selective A_2A receptor agonist vasodilator stress agent, regadenoson, is safe and effective in ESRD and has recently been approved by the Food and Drug Administration for use in this population. Ancillary stress MPI findings, namely heart rate response to vasodilator stress, can provide incremental risk stratification.

SUMMARY

While myocardial perfusion imaging is widely used as a risk assessment tool, its utilization and clinical implications in the ESRD population are controversial. Though stress SPECT-MPI has imperfect diagnostic accuracy in this specific patient population, it is still a valuable non-invasive modality in cardiovascular risk assessment.

Cardiovascular disease in patients with chronic kidney disease: a neglected subgroup

The burden of non-communicable diseases has increased exponentially over the past decade and they account for majority of the health-related morbidity and mortality worldwide. In line with this, the prevalence of chronic kidney disease (CKD) has been increasing over the years. CKD progresses through stages and it is well known that patients are more likely to die than to progress to end-stage renal disease. The presence of multiple classical and novel risk factors predisposes this group of patients to premature cardiovascular mortality. Though being a common entity, prevention, diagnosis and treatment of cardiovascular diseases in CKD are mired with controversies. This is due to the fact that many of the well-established diagnostic modalities and treatment strategies have not been studied in detail in patients with CKD. Moreover, most of the studies have excluded patients with renal dysfunction though they are at a higher risk for adverse outcomes and require specific dose modifications. This has limited the evidence base for optimal decision making. In this review, we aim to cover the risk factors, diagnosis and effectiveness of interventional strategies in patients with CKD.

Role of Coronary Angiography in the Assessment of Cardiovascular Risk in Kidney Transplant Candidates

Cardiovascular disease is the leading cause of death among those with renal insufficiency, those requiring dialysis, and in recipients of kidney transplants reflecting the greatly increased cardiovascular burden that these patients carry. The best method by which to assess cardiovascular risk in such patients is not well established. In the present study, 1,225 patients seeking a kidney transplant, over a 30-month period, underwent cardiovascular evaluation. Two hundred twenty-five patients, who met selected criteria, underwent coronary angiography that revealed significant coronary artery disease (CAD) in 47%. Those found to have significant disease underwent revascularization. Among the patients found to have significant CAD, 74% had undergone a nuclear stress test before angiography and 65% of these stress tests were negative for ischemia. The positive predictive value of a nuclear stress test in this patient population was 0.43 and the negative predictive value was 0.47. During a 30-month period, 28 patients who underwent coronary angiography received an allograft. None of these patients died, experienced a myocardial infarction, or lost their allograft. The annual mortality rate of those who remained on the waiting list was well below the national average. In conclusion, our results indicate that, in renal failure patients, noninvasive testing fails to detect the majority of significant CAD, that selected criteria may identify patients with a high likelihood of CAD, and that revascularization reduces mortality both for those on the waiting list and for those who receive an allograft.

Current practices in coronary artery disease evaluation of renal transplant candidates prior to renal transplantation

Cardiovascular disease is the leading cause of morbidity and mortality in renal transplant recipients and candidates awaiting transplant. Pre-transplant coronary artery disease evaluation can aid in determining transplant candidacy, identifying patients who may benefit from pre-operative cardiac intervention, and implementing measures to reduce perioperative and post-transplant cardiovascular events. However, the choice of investigations and approach in evaluation has yet to be well defined. This article aims to review the evidence for the use of non-invasive investigations and coronary angiography in prognostication, as well as the evidence for revascularization in reducing future cardiac events. The article will also summarize international recommendations and describe the local practice in coronary artery disease evaluation prior to transplant.

Diagnostic accuracy of cadmium-zinc-telluride-based myocardial perfusion SPECT: impact of attenuation correction using a co-registered external computed tomography

INTRODUCTION

Computed tomography (CT)-based attenuation correction (AC) improves the accuracy of standard myocardial perfusion SPECT. Most dedicated cadmium-zinc-telluride (CZT) SPECT cameras are not equipped with an integrated CT component. We aimed to determine the impact of AC on diagnostic performance of CZT SPECT using co-registration with an external low-dose CT.

METHODS

Sixty patients underwent CZT SPECT (GE Discovery 530c) with (99m)Tc-sestamibi at rest and following regadenoson stress. Using commercial software, SPECT images were co-registered with a low-dose CT acquired on a separate system (GE Discovery 670NMCT). Attenuation corrected and non-corrected (NC) images were reconstructed using an iterative algorithm. Accuracy was measured in 44 patients who had undergone invasive angiography within 6 months. Normalcy was compared in the remaining 16 patients who had a low pre-test likelihood (<5%) of coronary artery disease (CAD).

RESULTS

Summed stress and rest scores were significantly lower in AC images (9 ± 8 vs. 13 ± 9 and 6 ± 7 vs. 10 ± 9, P = 0.01), while summed difference score did not differ. According to angiography, 38 patients had significant CAD in 71 vascular territories. Attenuation correction improved accuracy globally (P = 0.03) and in RCA territory (P = 0.008). Specificity improved both globally (100 vs. 40%, P < 0.05) and in each individual territory (LAD: 63 vs. 36%, LCX: 70 vs. 33%, RCA: 81 vs. 19%, P < 0.01). Normalcy was 100% for AC and 62.5% for NC images (P < 0.05).

CONCLUSION

Attenuation correction with a co-registered external CT is feasible using CZT cameras and improves diagnostic accuracy mostly by improving specificity over uncorrected images.

Coronary events in obese hemodialysis patients before and after renal transplantation

We examined the impact of obesity (BMI ≥30 kg/m(2) , n = 357) on prognosis in 1696 hemodialysis (HD) patients before and after renal transplantation (TX). End-points were coronary events, composite cardiovascular (CV) events, and death. Obese HD patients were older (55.9 ± 9.2 vs. 54.2 ± 11), had more diabetes (54% vs. 40%), dyslipidemia (49% vs. 30%), altered myocardial scan (38% vs. 31%), myocardial infarction (MI) (16% vs. 10%), coronary intervention (11% vs. 7%), higher total cholesterol (186 ± 52 vs. 169 ± 47), and triglycerides (219 ± 167 vs. 144 ± 91). Obese undergoing TX had more dyslipidemia (46% vs. 31%), angina (23% vs. 14%), MI (18% vs. 5%), increased total cholesterol (185 ± 56 vs. 172 ± 48), and triglycerides (237 ± 190 vs. 149 ± 100). Obesity was independently associated with coronary events (log-rank = 0.008, HR 2.55% CI 1.27-5.11) and death (log-rank 0.046, HR 1.52, % CI 1.007-2.30) in TX but not in HD. Obese HD patients had more risk factors and ischemic heart disease, but these characteristics did not interfere with prognosis. In TX patients, obesity predicts coronary events and death.

Screening and risk stratification of coronary artery disease in end-stage renal disease

End-stage renal disease (ESRD) is a growing global health problem with major health and economic implications. Cardiovascular complication is the major cause of morbidity and mortality in this population. Clustering of traditional atherosclerotic risk factors, such as diabetes, systemic inflammation, and altered mineral metabolism, contributes to enhanced systemic atherosclerosis in patients with ESRD. Prevalence of obstructive coronary artery disease (CAD) on coronary angiography exceeds 50% in this population. Despite having extensive CAD and vascular disease, patients with ESRD often do not present with classic symptoms because of impaired exercise capacity and diabetes. Furthermore, clinical trial data are exceedingly lacking in this population, resulting in considerable clinical equipoise regarding the optimal approach to the identification and subsequent management of CAD in these patients. Traditional clinical screening tools, including conventional risk prediction models, are significantly limited in their predictive accuracy for cardiovascular events in patients with ESRD. Noninvasive cardiac stress imaging modalities, such as nuclear perfusion and echocardiography, have been shown to improve the traditional clinical model in identifying the presence of CAD. Furthermore, they add incremental prognostic information to angiographic data. Novel imaging techniques and biomarker assays hold significant promise in further improving the ability to identify and risk-stratify for CAD. This review focuses on the current understanding of the clinical risk profile of asymptomatic patients with ESRD with an emphasis on the strengths and limitations of various noninvasive cardiovascular imaging modalities, including the role of novel methods in refining risk prediction. In addition, issues and challenges pertaining to the optimal timing of initial risk assessment ("screening") and possible repeat screening ("surveillance") are addressed. We also summarize the current data on the approach to the patient with ESRD being evaluated for transplantation in the context of recent guidelines and position statements by various professional societies.