Coronary Artery Disease in patients with End-Stage Kidney Disease; Current perspective and gaps of knowledge

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.

Assessment of the Influence of Asymmetric Triacetate Cellulose Membrane on the Rate of Removal of Middle Molecular Weight Uremic Toxins in Patients Treated with Postdilution Online Hemodiafiltration

BACKGROUND: Postdilution online hemodiafiltration (OL-HDF) effectively removes uremic toxins of middle molecular weight from the blood of patients with end-stage chronic kidney disease. The rate of removal of uremic toxins depends on the type of dialysis membrane, blood flow rate (Qb), net ultrafiltration flow rate (Qnuf), and total convective volume (Vconv). AIM: The aim of this study was to examine the efficacy of asymmetric triacetate cellulose dialysis membrane in patients on post-dilution OL-HDF. METHODS: Thirty-five patients treated with post-dilution OL-HDF hemodiafiltration for at least 3 months were examined. The main parameters for assessing the efficiency of removal of uremic toxins of middle molecular weight are the concentration of β2-microglobulin (β2-M) and interleukin-6 (IL-6) in serum before and after a single session of post-dilution OL-HDF. The followings were used for statistical analysis: Kolmogorov–Smirnov test, Student’s T test for bound samples and Wilcoxon test. RESULTS: The average Vconv was 20.90 ± 3.30 liters/session. The β2-M reduction index during a single session of postdilution OL-HDF was 71.10 ± 6.39%, the IL-6 reduction index was 43.75 ± 15.60%, and the albumin reduction index was 4.55 ± 2.31%. CONCLUSION: The asymmetric triacetate cellulose dialysis membrane effectively removes β2-M and IL-6 during a single session of postdilution OL-HDF. The β2-M reduction index is ∼70%, the IL-6 reduction index is ∼40%, and albumin loss is <4.0 g/4 h. The examined dialysis membrane and dialysis modality prevent the development of amyloidosis associated with dialysis, microinflammation and reduce the risk of developing atherosclerotic cardiovascular diseases in the population of patients treated with regular hemodiafiltration.

Prognostic value of myocardial perfusion imaging in patients with chronic kidney disease: A systematic review and meta-analysis

BACKGROUND

We performed a systematic review and meta-analysis to investigate the prognostic value of stress myocardial perfusion single-photon emission computed tomography (MPS) in predicting adverse cardiovascular events in patients with chronic kidney disease (CKD).

METHODS

Studies published from inception until July 2020 were identified by PubMed and Embase databases search. Studies were included if they evaluated CKD patients referred for stress MPS, providing data on adjusted hazard ratio (HR) for the occurrence of adverse events. For studies providing only non-adjusted HR, the univariable risk estimate was included in the analysis. Pooled HR and 95% confidence interval (CI) were estimated using a random effects model to compare patients with abnormal and normal MPS. Whenever possible, incidence rate ratio (IRR) was also calculated and pooled.

RESULTS

Sixteen eligible studies were identified including 7834 patients with a follow-up range from 1 to 4.4 years. Eleven articles included patients with end-stage renal disease (IV-V CKD stage), 3 articles with III-V CKD stage and 2 articles with I-V CKD stage. The pooled HR for the occurrence of adverse events was 2.02 (95% CI 1.68-2.42) and heterogeneity was 34%. Among the included studies, 5 reported the HR for the occurrence of hard events, with a pooled HR of 2.36 (95% CI 1.77-3.13). A total of 8 studies reported data useful to calculate the IRR in patients with normal and abnormal perfusion. The pooled IRR was 2.37 (95% CI 1.63-3.47) and heterogeneity was 60%. At meta-regression analysis, we found an association between HR for adverse events and age, hypertension and smoking, while no significant association was found between HR for hard events and demographic and clinical variables.

CONCLUSIONS

In patients with CKD an abnormal myocardial perfusion at stress MPS is associated with adverse cardiovascular events.

The fundamental role of stress echo in evaluating coronary artery disease in specific patient populations

Stress echocardiography (SE) was initially used for assessing patients with known or suspected coronary heart disease by detecting and evaluating myocardial ischemia and viability. The implementation of SE has gradually been extended to several cardiovascular diseases beyond coronary artery disease, and SE protocols have been modified and adapted for the detection of coronary artery disease (CAD) or other cardiovascular diseases in specific patient populations. This review attempts to summarize current data concerning SE implementation and clinical value in these specific and diverse populations: patients with an intramural course of a coronary artery - known as a myocardial bridge, chronic severe or end-stage hepatic disease, chronic severe or end-stage kidney disease, cardiac allograft vasculopathy, patients scheduled for solid-organ transplantation and other intermediate and high-risk surgery and, finally, patients treated with anticancer drugs or radiotherapy.

Screening for occult coronary artery disease in potential kidney transplant recipients: time for reappraisal?

Screening for occult coronary artery disease in potential kidney transplant recipients has become entrenched in current medical practice as the standard of care and is supported by national and international clinical guidelines. However, there is increasing and robust evidence that such an approach is out-dated, scientifically and conceptually flawed, ineffective, potentially directly harmful, discriminates against ethnic minorities and patients from more deprived socioeconomic backgrounds, and unfairly denies many patients access to potentially lifesaving and life-enhancing transplantation. Herein we review the available evidence in the light of recently published randomized controlled trials and major observational studies. We propose ways of moving the field forward to the overall benefit of patients with advanced kidney disease.