Comparison of clinical outcomes of coronary artery bypass grafting and percutaneous transluminal coronary angioplasty in renal dialysis patients

Acute coronary syndromes in chronic hemodialysis patients: a series of 34 cases (case series)

Cardiovascular diseases, particularly acute coronary syndrome, are the leading cause of death in chronic hemodialysis patients. Our study aims to analyze the pathophysiological, clinical, angiographic, and therapeutic characteristics of coronary heart disease in hemodialysis patients.

PATIENTS AND METHODS

This single-centered retrospective descriptive study included 34 hemodialysis patients hospitalized in the cardiovascular ICU.

RESULTS

The mean age of patients in our study was 64.4±11.3 years. The main cardiovascular risk factor found in our study was age, with a prevalence of 76.50%, followed by hypertension, with a prevalence of 67.60%. Diabetes was present in 55.90% of patients. The authors also found that 17.90% of patients were obese, and 29.40% had abdominal obesity. The main cause of renal disease in our study was diabetic nephropathy (52.90% of cases), followed by hypertensive nephropathy (23.50% of cases). ST segment elevation myocardial infarction was found in 14.70% of cases, and non-ST-segment elevation myocardial infarction in 85.30% of cases. Coronary angiography was performed in 76.40% of patients. Single-vessel coronary artery disease (CAD) was found in 20%, two-vessel CAD in 50%, and three-vessel CAD in 30% of the cases. Coronary artery calcifications were observed in 21.42% of cases. 38.23% had an angioplasty, and 20.58% were referred for a coronary artery bypass graft.

CONCLUSION

Despite the high mortality rate after acute coronary syndrome, hemodialysis patients are less likely to undergo diagnostic angiography or coronary revascularization. Patients on hemodialysis tend to have multiple, diffuse, calcified CAD.

Percutaneous coronary intervention versus coronary artery bypass graft surgery in dialysis-dependent patients: A pooled meta-analysis of reconstructed time-to-event data

OBJECTIVE

Το perform a systematic review with meta-analysis of published data comparing outcomes between a percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) in dialysis-dependent patients.

METHODS

We searched PubMed, Scopus, and Cochrane databases for studies including dialysis-dependent patients who underwent either CABG or PCI. This meta-analysis follows the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. We conducted one-stage and two-stage meta-analysis with Kaplan-Meier-derived individual patient data for overall survival and meta-analysis with the random-effects model for the in-hospital mortality and repeat revascularization.

RESULTS

Twelve studies met our eligibility criteria, including 13,651 and 28,493 patients were identified in the CABG and PCI arms, respectively. Patients who underwent CABG had overall improved survival compared with those who underwent PCI at the one-stage meta-analysis (hazard ratio [HR]: 1.12, 95% confidence interval [CI]: 1.09-1.16, p < .0001) and the two-stage meta-analysis (HR: 1.15, 95% CI: 1.08-1.23, p < .001, I²  = 30.0%). Landmark analysis suggested that PCI offers better survival before the 8.5 months of follow-up (HR: 0.96, 95% CI: 0.92-0.99, p = .043), while CABG offers an advantage after this timepoint (HR: 1.3, 95% CI: 1.22-1.32, p < .001). CABG was associated with increased odds for in-hospital mortality (odds ratio [OR]: 1.70, 95% CI: 1.50-1.92, p < .001, I²  = 0.0%) and decreased odds for repeat revascularization (OR: 0.22, 95% CI: 0.14-0.34, p < .001, I²  = 58.08%).

CONCLUSIONS

In dialysis-dependent patients, CABG was associated with long-term survival but a higher risk for early mortality. The risk for repeat revascularization was higher with PCI.

Influence of Ipsilateral Graft Inflow to Arteriovenous Fistula for Hemodialysis in Coronary Bypass Surgery

In coronary artery bypass grafting (CABG) for patients on hemodialysis, there has been concern about “coronary steal”. This study aims to evaluate the influence of using an in situ internal thoracic artery (ITA) ipsilateral to a preexisting arteriovenous fistula (AVF) in dialysis-dependent patients undergoing CABG. Between 2004 and 2018, dialysis-dependent patients with AVFs who underwent CABG were enrolled. According to the locational relationship of AVFs and in situ ITA grafts, the patients were divided into the ipsilateral group (n = 22) and the contralateral group (n = 21). Inverse probability weighting analysis was used to estimate and compare the late clinical outcomes. The late cardiac-related adverse events were not significantly different between the two groups: “major adverse cardiovascular and cerebrovascular events (MACCE)” (p = 0.090), “composite outcome of recurrent angina and coronary re-intervention” (p = 0.600). The in situ ITA graft of CABG on the ipsilateral side to AVF was not a significant risk factor for MACCE or the composite outcome of recurrent angina and coronary re-intervention. There was no statistically significant difference in the graft patency between the groups. Therefore, it might not be necessary to avoid using an in situ ITA on the ipsilateral side of an upper-arm AVF for optimal coronary artery bypass grafting in dialysis-dependent patients.

Coronary revascularisation in patients with chronic kidney disease and end-stage renal disease: A meta-analysis

OBJECTIVES

To compare coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) for revascularising coronary arteries in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD). CKD is described as a continuous decrease in the glomerular filtration rate or abnormalities in kidney structure or function.

METHODS

PubMed, Cochrane Library and Embase databases were searched for studies on the revascularisation of coronary arteries in patients with CKD and ESRD.

RESULTS

Since no randomised controlled trials (RCTs) have addressed this issue so far, 31 observational studies involving 74 805 patients were included in this meta-analysis. Compared with PCI, patients undergoing CABG have significantly higher early mortality (CKD: RR = 1.62, 95% CI: 1.17-2.25, pheterogeneity = 0.476, I²  = 0; ESRD: RR = 1.99, 95% CI: 1.46-2.71, pheterogeneity = 0.001, I²  = 66.9%). Patients with ESRD undergoing CABG have significantly lower all-cause mortality (RR = 0.95, 95% CI: 0.93-0.96, pheterogeneity < 0.001, I²  = 82.9%) and cardiac mortality (RR = 0.73, 95% CI: 0.58-0.92, pheterogeneity = 0.908, I²  = 0). The long-term risk of repeat revascularisation (CKD: RR = 0.24, 95% CI: 0.19-0.30, pheterogeneity = 0.489, I²  = 0; ESRD: RR = 0.23, 95% CI: 0.15-0.34, pheterogeneity = 0.012, I²  = 54.4%) and myocardial infarction (CKD: RR = .57, 95% CI: 0.38-0.85, pheterogeneity = 0.025, I²  = 49.9%; ESRD: RR = 0.42, 95% CI: 0.40-0.44, pheterogeneity = 0.49, I²  = 0) remained significantly higher in the PCI group.

CONCLUSIONS

Patients with ESRD, but not CKD, who underwent CABG had significantly lower all-cause mortality and cardiac mortality. However, CABG was associated with an increased risk of early mortality in patients with CKD or ESRD. Adequately powered, contemporary, prospective RCTs are needed to define the optimal revascularisation strategy for patients with CKD and ESRD.

Optimal treatment strategies for coronary artery disease in patients with advanced kidney disease: a meta-analysis

Background:

Coronary artery disease (CAD) is the leading cause of death in advanced kidney disease. However, its best treatment has not been determined.

Methods:

We searched PubMed and Cochrane databases and scanned references to related articles. Studies comparing the different treatments for patients with CAD and advanced CKD (estimated glomerular filtration rate <30 ml/min/1.73 m² or dialysis) were selected. The primary result was all-cause death, classified according to the follow-up time: short-term (<1 month), medium-term (1 month-1 year), and long-term (>1 year).

Results:

A total of 32 studies were selected to enroll 84,498 patients with advanced kidney disease. Compared with medical therapy (MT) alone, percutaneous coronary intervention (PCI) was associated with low risk of short-, medium-term and long-term all-cause death (more than 3 years). For AMI patients, compared with MT, PCI was not associated with low risk of short- and medium-term all-cause death. For non-AMI patients, compared with MT, PCI was associated with low risk of long-term mortality (more than 3 years). Compared with MT, coronary artery bypass surgery (CABG) had no significant advantages in each follow-up period of all-cause death. Compared with PCI, CABG was associated with a high risk of short-term death, but low risk of long-term death: 1–3 years; more than 3 years. CABG could also reduce the risk of long-term risk of cardiac death, major adverse cardiovascular events (MACEs), myocardial infarction (MI), and repeat revascularization.

Conclusions:

In patients with advanced kidney disease and CAD, PCI reduced the risk of short-, medium- and long- term (more than 3 years) all-cause death compared with MT. Compared with PCI, CABG was associated with a high risk of short-term death and a low risk of long-term death and adverse events.

Management of acute intradialytic cardiovascular complications: Updated overview (Review)

An increasing number of patients require renal replacement therapy through dialysis and renal transplantation. Chronic kidney disease (CKD) affects a large percentage of the world's population and has evolved into a major public health concern. Diabetes mellitus, high blood pressure and a family history of kidney failure are all major risk factors for CKD. Patients in advanced stages of CKD have varying degrees of cardiovascular damage. Comorbidities of these patients, include, on the one hand, hypertension, hyperlipidemia, hyperglycemia, hyperuricemia and, on the other hand, the presence of mineral-bone disorders associated with CKD and chronic inflammation, which contribute to cardiovascular involvement. Acute complications occur quite frequently during dialysis. Among these, the most important are cardiovascular complications, which influence the morbidity and mortality rates of this group of patients. Chronic hemodialysis patients manifest acute cardiovascular complications such as intradialytic hypotension, intradialytic hypertension, arrhythmias, acute coronary syndromes and sudden death. Thus, proper management is extremely important.

Risk analysis of dialysis-dependent patients who underwent coronary artery bypass grafting: Effects of dialysis modes on outcomes

Cardiovascular disease is the major morbidity and leading cause of mortality for dialysis-dependent patients. This study aimed to stratify the risk factors and effects of dialysis modes in relation to coronary artery bypass grafting (CABG) surgery among dialysis-dependent patients.This retrospective study enrolled dialysis-dependent patients who underwent CABG from October 2005 to January 2015. All data of demographics, medical history, surgical details, postoperative complications, and in-hospital mortality were analyzed, and patients were categorized as those with or without in-hospital mortality and those with preoperative hemodialysis (HD) or peritoneal dialysis (PD).Of 134 enrolled patients, 25 (18.7%) had in-hospital mortality. Multivariate analyses identified that older age [odds ratio (OR): 1.110, 95% confidence interval (CI): 1.030-1.197, P = .006], previous stroke history (OR: 5.772, 95% CI: 1.643-20.275, P = .006), PD (OR: 19.607, 95% CI: 3.676-104.589, P < .001), and emergent operation (OR: 8.788, 95% CI: 2.697-28.636, P < .001) were statistically significant risk factors for in-hospital mortality among dialysis-dependent patients with CABG surgery. Patients with PD had a higher in-hospital mortality rate (58.3% vs 14.8%, P < .001) and lower 1-year overall survival (33.3% vs 56.6%, P = .031) than did HD patients. The major in-hospital mortality cause was cardiac events among HD patients and septic shock among PD patients.Among dialysis patients who received CABG, those with older age, previous stroke history, PD, and emergent operation had higher risks. Those with PD were prone to poorer in-hospital outcomes after CABG surgery.

Effectiveness of Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting in Patients With End-Stage Renal Disease

The optimal coronary revascularization strategy (coronary artery bypass grafting [CABG] or percutaneous coronary intervention [PCI]) in patients with end-stage renal disease (ESRD) remains uncertain. We performed an updated systematic review and meta-analysis of observational studies comparing CABG and PCI in patients with ESRD using a random-effects model for the primary outcome of long-term all-cause mortality. Our review registered through PROSPERO included observational studies published after 2011 to ensure overlap with previous studies and identified 7 new studies for a total of 23. We found that the median sample size in the selected studies was 125 patients (25 to 15,784) with a large variation in the covariate risk adjustment and only 3 studies reporting the indications for the revascularization strategy. CABG was associated with a small reduction in mortality (relative risk 0.92, 95% CI 0.89 to 0.96) with significant heterogeneity demonstrated (p = 0.005, I(2) = 48.6%). Subgroup analysis by categorized "year of study initiation" (<1990, 1991 to 2003, >2004) further confirmed the summary estimate trending toward survival benefit of CABG along with a substantial decrease in heterogeneity after 2004 (p = 0.64, I(2) = 0%). In conclusion, our updated systematic review and meta-analysis demonstrated that in patients with ESRD referred for coronary revascularization, CABG was associated with a small decrease in the relative risk of long-term mortality compared with PCI. The generalizability of the finding to all patients with ESRD referred for coronary revascularization is limited because of a lack of known indications for coronary revascularization, substantial variation in covariate risk adjustment, and lack of randomized clinical trial data.

The impact of renal impairment on long-term safety and effectiveness of drug-eluting stents

Background

Renal impairment (RI) is associated with impaired prognosis in patients with coronary artery disease. Clinical and angiographic outcomes of patients undergoing percutaneous coronary intervention (PCI) with the use of drug-eluting stents (DES) in this patient population are not well established.

Methods

We pooled individual data for 5,011 patients from 3 trials with the exclusive and unrestricted use of DES (SIRTAX - N = 1,012, LEADERS - N = 1,707, RESOLUTE AC - N = 2,292). Angiographic follow-up was available for 1,544 lesions. Outcomes through 2 years were stratified according to glomerular filtration rate (normal renal function: GFR≥90 ml/min; mild RI: 90<GFR≥60 ml/min; moderate/severe RI GFR<60 ml/min).

Results

Patients with moderate/severe RI had an increased risk of cardiac death or myocardial infarction ([MI], OR 2.14, 95%CI 1.36–3.36), cardiac death (OR 2.21, 95%CI 1.10–4.46), and MI (OR 2.02, 95%CI 1.19–3.43) compared with patients with normal renal function at 2 years follow-up. There was no difference in cardiac death or MI between patients with mild RI compared to those with normal renal function (OR 1.10, 95%CI 0.75–1.61). The risk of target-lesion revascularization was similar for patients with moderate/severe RI (OR 1.17, 95%CI 0.70–1.95) and mild RI (OR 1.16, 95%CI 0.81–1.64) compared with patients with normal renal function. In-stent late loss and in-segment restenosis were not different for patients with moderate/severe RI, mild RI, and normal renal function.

Conclusions

Renal function does not affect clinical and angiographic effectiveness of DES. However, prognosis remains impaired among patients with moderate/severe RI.

Optimal strategy of coronary revascularization in chronic kidney disease patients: a meta-analysis

BACKGROUND

Patients with chronic kidney disease (CKD) have high risks of coronary artery disease (CAD). Coronary revascularization is beneficial for long-term survival, but the optimal strategy remains still controversial.

METHODS

We searched studies that have compared percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) for revascularization of the coronary arteries in CKD patients. Short-term (30 days or in-hospital) mortality, long-term (at least 12 months) all-cause mortality, cardiac mortality and the incidence of late myocardial infarction and recurrence of revascularization were estimated.

RESULTS

28 studies with 38,740 patients were included. All were retrospective studies from 1977 to 2012. Meta-analysis showed that PCI group had lower short-term mortality (OR 0.55, 95% CI 0.41 to 0.73, P<0.01), but had higher long-term all-cause mortality (OR 1.29, 95% CI 1.23 to 1.35, P<0.01). Higher cardiac mortality (OR 1.08, 95% CI 1.01 to 1.15, P<0.05), higher incidence of late myocardial infarction (OR 1.78, 95% CI 1.65 to 1.91, P<0.01) and recurring revascularization rate (OR 2.94, 95%CI 2.15 to 4.01, P<0.01) is found amongst PCI treated patients compared to CABG group.

CONCLUSIONS

CKD patients with CAD received CABG had higher risk of short-term mortality but lower risks of long-term all-cause mortality, cardiac mortality and late myocardial infarction compared to PCI. This could be due to less probable repeated revascularization.

Dysregulation of the Mammalian Target of Rapamycin and p27Kip1 Promotes Intimal Hyperplasia in Diabetes Mellitus

The proliferation and migration of vascular smooth muscle cells (VSMCs) in the intima of an artery, known as intimal hyperplasia, is an important component of cardiovascular diseases. This is seen most clearly in the case of in-stent restenosis, where drug eluting stents are used to deliver agents that prevent VSMC proliferation and migration. One class of agents that are highly effective in the prevention of in-stent restenosis is the mammalian Target of Rapamycin (mTOR) inhibitors. Inhibition of mTOR blocks protein synthesis, cell cycle progression, and cell migration. Key to the effects on cell cycle progression and cell migration is the inhibition of mTOR-mediated degradation of p27Kip1 protein. p27Kip1 is a cyclin dependent kinase inhibitor that is elevated in quiescent VSMCs and inhibits the G1 to S phase transition and cell migration. Under normal conditions, vascular injury promotes degradation of p27Kip1 protein in an mTOR dependent manner. Recent reports from our lab suggest that in the presence of diabetes mellitus, elevation of extracellular signal response kinase activity may promote decreased p27Kip1 mRNA and produce a relative resistance to mTOR inhibition. Here we review these findings and their relevance to designing treatments for cardiovascular disease in the presence of diabetes mellitus.

Multivessel coronary artery bypass grafting versus percutaneous coronary intervention in ESRD

Thirty to sixty percent of patients with ESRD on dialysis have coronary heart disease, but the optimal strategy for coronary revascularization is unknown. We used data from the United States Renal Data System to define a cohort of 21,981 patients on maintenance dialysis who received initial coronary revascularization with either coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) between 1997 and 2009 and had at least 6 months of prior Medicare coverage as their primary payer. The primary outcome was death from any cause, and the secondary outcome was a composite of death or myocardial infarction. Overall survival rates were consistently poor during the study period, with unadjusted 5-year survival rates of 22%-25% irrespective of revascularization strategy. Using multivariable-adjusted proportional hazards regression, we found that CABG compared with PCI associated with significantly lower risks for both death (HR=0.87, 95% CI=0.84-0.90) and the composite of death or myocardial infarction (HR=0.88, 95% CI=0.86-0.91). Results were similar in analyses using a propensity score-matched cohort. In the absence of data from randomized trials, these results suggest that CABG may be preferred over PCI for multivessel coronary revascularization in appropriately selected patients on maintenance dialysis.

Perioperative outcomes among patients with end-stage renal disease following coronary artery bypass surgery in the USA

BACKGROUND

Patients with end-stage renal disease (ESRD) requiring chronic haemodialysis who undergo coronary artery bypass graft surgery (CABG) are at significant risk for perioperative mortality. However, the impact of changes in ESRD patient volume and characteristics over time on operative outcomes is unclear.

METHODS

Using the Nationwide Inpatient Sample database (1988-03), we evaluated rates of CABG surgery with and without concurrent valve surgery among ESRD patients and outcomes including in-hospital mortality, and length of hospital stay. Multivariate regression models were used to account for patient characteristics and potential cofounders.

RESULTS

From 1988 to 2003, annual rates of CABG among ESRD patients doubled from 2.5 to 5 per 1000 patient-years. Concomitantly, patient case-mix changed to include patients with greater co-morbidities such as diabetes, hypertension and obesity (all P < 0.001). Nonetheless, among ESRD patients, in-hospital mortality rates declined nearly 6-fold from over 31% to 5.4% (versus 4.7% to 1.8% among non-ESRD), and the median length of in-hospital stay dropped in half from 25 to 13 days (versus 14 to 10 days among non-ESRD).

CONCLUSIONS

Since 1988, an increasing number of patients with ESRD have been receiving CABG in the USA. Despite increasing co-morbidities, operative mortality rates and length of in-hospital stay have declined substantially. Nonetheless, mortality rates remain almost 3-fold higher compared to non-ESRD patients indicating a need for ongoing improvement.

Optimal method of coronary revascularization in patients receiving dialysis: systematic review

BACKGROUND AND OBJECTIVES

Patients receiving dialysis have a high burden of cardiovascular disease. Some receive coronary artery revascularization but the optimal method is controversial.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The authors reviewed any randomized controlled trial or cohort study of 10 or more patients receiving maintenance dialysis which compared coronary artery bypass graft (CABG) to percutaneous intervention (PCI) for revascularization of the coronary arteries. The primary outcomes were short-term (30 d or in-hospital) and long-term (at least 1 year) mortality.

RESULTS

Seventeen studies were found. There were no randomized trials: all were retrospective cohort studies from years 1977 to 2002. There were some baseline differences between the groups receiving CABG compared with those receiving PCI, and most studies did not consider results adjusted for such characteristics. Given the variability among studies and their methodological limitations, few definitive conclusions about the optimal method of revascularization could be drawn. In an exploratory meta-analysis, short-term mortality was higher after CABG compared to PCI. A substantial number of patients died over a subsequent 1 to 5 yr, with no difference in mortality after CABG compared to PCI.

CONCLUSIONS

Although decisions about the optimal method of coronary artery revascularization in dialysis patients are undertaken routinely, it was surprising to see how few data has been published in this regard. Additional research will help inform physician and patient decisions about coronary artery revascularization.

[Myocardial revascularization in patients with chronic renal failure]

The incidence of chronic renal failure has increased in the last years in industrialized countries. In Spain the prevalence of this pathology is estimated at 10-12% of the population, and the stages III-V of the disease, corresponding to the estimated glomerular filtration rate less than 60 ml/min/m2, represent the 5%. From the cardiovascular point of view, both chronic and acute coronary syndrome is a very important subgroup of patients because of the increased association between chronic renal failure and coronary artery disease. In fact, ACS is the main cause of death in patients with advanced chronic renal failure. Frequently, this kind of patients are excluded from prospective randomized clinical trials, consequently scientific evidence is not available to guide the therapy of coronary revascularization.

Off-pump coronary artery bypass grafting improves in-hospital mortality in patients with dialysis-dependent renal failure

OBJECTIVE

Patients with chronic dialysis-dependent end-stage renal disease are increasingly referred for coronary artery bypass grafting (CABG) and their early outcome is less favorable. Off-pump CABG (OPCAB) has achieved encouraging results in high-risk patients. Therefore, we designed this retrospective study to test the hypothesis that OPCAB reduced surgical risks in dialysis patients.

METHODS

From January 2000 to December 2005, 294 dialysis-dependent patients received isolated CABG at the Washington Hospital Center. Among them, 168 underwent OPCAB (off-pump group), and 126, CABG with cardiopulmonary bypass (CPB) (on-pump group). The in-hospital outcomes were analyzed.

RESULTS

The two groups were comparable in terms of preoperative characteristics. The Parsonnet's Bedside Score of the off-pump group was similar to that of the on-pump group (32.0 vs. 32.0, P=.57). The in-hospital mortality of the off-pump group was significantly lower than that of the on-pump group (5.4% vs. 11.9%, P=.04). Although the percentage of patients who received transfusions was similar, the on-pump group received more total transfusions. Logistic regression analysis revealed that use of CPB independently predicted in-hospital mortality [odds ratio (OR), 5.0; 95% confidence interval, 1.78-13.85; P<.01] and perioperative myocardial infarction (MI; OR, 5.1; 95% confidence interval, 1.18-22.40; P=.03). No significant difference in long-term survival at 4 years was absorbed between the two groups of hospital survivors.

CONCLUSIONS

Our data suggest that OPCAB is a safe alternative to on-pump CABG in dialysis patients. Avoiding CPB resulted in less perioperative blood utilization, MI, and hospital mortality.

Coronary artery bypass grafting in patients on maintenance dialysis: is peritoneal dialysis a risk factor of operative mortality?

BACKGROUND

Increasing numbers of patients on dialysis are undergoing coronary artery bypass grafting (CABG). We undertook this retrospective study to identify risk factors of operative mortality in dialysis patients who underwent CABG.

PATIENTS AND METHODS

We performed retrospective analysis of 105 patients who were on dialysis for at least two months before surgery and who underwent CABG in Toronto General Hospital from 1997 to 2006. Using prospectively collected data from the Division of Cardiovascular Surgery Database of Toronto General Hospital, we collected data on comorbidities, procedures, modality change during hospitalization, and operative outcomes. Logistic regression was used to assess risk factors of operative mortality.

RESULTS

One hundred and five maintenance dialysis patients (40 PD and 65 HD) who met the inclusion criteria were studied. Overall in-hospital mortality was 7.6%. Atrial fibrillation and pneumonia occurred in 16.2 and 9.5%, respectively, of all dialysis patients. Among PD patients, rates of post-operative dialysate leak and peritonitis were 10 and 12.5%, respectively. Among HD patients, 4.6% experienced post-operative AV access thrombosis. Logistic regression showed older age (>or=70 years) and peritoneal dialysis are independent risk factors of operative mortality.

CONCLUSION

In this retrospective study, older patients on PD had higher operative mortality than HD patients. These findings suggest extra care should be taken when CABG is considered for PD patients over 70 years old. In this study we could not identify the reason(s) for the high mortality of elderly peritoneal dialysis patients undergoing CABG.

Management of ischemic heart disease in patients with chronic kidney disease

Patients with chronic kidney disease (CKD) and ischemic heart disease (IHD) have strikingly high mortality rates. In the general population, there has been a reduction in the mortality and morbidity rates for IHD through the implementation of effective risk-factor-reduction programs and better interventions for patients with established IHD. No such trend has been observed in patients with end-stage kidney disease. This review article addresses the following topics: (i) epidemiology, pathogenesis, clinical CKD patients with IHD; (ii) diagnostic modalities for IHD and their limitation in CKD patients; (iii) medical treatment options and revascularization strategies for these high-risk patients; and (iv) optimal cardiovascular risk management. Generally, in CKD patients with IHD an aggressive approach to IHD is warranted, a low threshold for diagnostic testing should be employed, and awaiting a clinical trial targeting these patients they should be considered for all proven strategies to improve outcomes.

Coronary revascularization in end-stage renal disease

Advanced coronary artery disease and acute cardiac events are the most common causes of death in patients with end-stage renal disease. Because of their heightened risk, end-stage renal disease patients are frequently referred for coronary revascularization. However, these patients are almost always excluded from trials examining various innovations in medical and revascularization interventions for cardiovascular conditions. Extrapolation of trial conclusions regarding dialysis patients can be misleading because the risk-benefit ratios of various interventions in this patient population can be markedly different. Thus, clinical decisions regarding the need for (and type of) coronary revascularization are based on retrospective outcome analyses from various databases. This article reviews the data available in the literature on the morbidity, mortality, and outcomes of dialysis patients undergoing surgical or percutaneous revascularization, particularly with the addition of drug-eluting stents to the available therapeutic options.

On-pump versus off-pump coronary surgery outcomes in patients requiring dialysis: perspectives from a single center and the United States experience

OBJECTIVE

Coronary artery bypass graft surgery carries increased risk for patients requiring dialysis compared with other groups. Little data exist comparing outcomes of on-pump and off-pump techniques in dialysis patients. This study compares outcomes of bypass grafting in dialysis patients with these two techniques at a single institution and in the United States Renal Data System (USRDS) database.

METHODS

From March 1997 to April 2004, 37 patients requiring dialysis underwent bypass graft surgery at our institution. On-pump surgery was performed for 16 patients and off-pump surgery for 21. From January 1, 2001, to December 31, 2002, a total of 3922 patients in the USRDS underwent bypass graft surgery. On-pump surgery was performed for 3382 and off-pump surgery for 540. Comparisons were made between patients undergoing on-pump and off-pump bypass surgery with respect to demographics, risk factors, and outcomes. Univariate analysis, the Kaplan-Meier method, and a multivariate Cox model were used.

RESULTS

Institutional analysis revealed similar patient demographics, risk factors, use of thoracic artery grafts, and number of distal anastomoses. Outcome analysis was significant for less postoperative atrial fibrillation with the off-pump technique: 37.5% on-pump and 4.8% off-pump (P = .028). USRDS data revealed all-cause survivals at 1 and 18 months of 87.5% and 59.5% for on-pump versus 88.3% and 61.9% for off-pump procedures (P = .226). In a comorbidity-adjusted Cox model, off-pump bypass grafting was associated with a 16% reduction in all-cause mortality (P = .032).

CONCLUSION

Off-pump bypass grafting is uncommon in patients in the United States who require dialysis. Off- pump bypass grafting provides a morbidity benefit and is associated with a lower risk of death.

Coronary surgery in patients requiring chronic hemodialysis

BACKGROUND

In uremic patients coronary surgery and the entire perioperative management is demanding.

METHODS

We analyzed retrospectively data from all patients requiring chronic hemodialysis who under went coronary artery bypass grafting (CABG) between January 1 2001 and December 31 2004 at the Deutsches Herzzentrum Berlin and compared them to those of a randomized nonuremic control group (n = 68), which consisted of patients who underwent CABG during the same period.

RESULTS

During the study period 6315 patients underwent coronary artery bypass grafting at the Deutsches Herzzentrum Berlin. Among these patients, we identified 71 chronic dialysis patients (1.12%). Among dialysis patients, we recorded a perioperative mortality of 5.6%. One-year survival rate was 87.7% among uremic patients and 91.0% in the control group; the corresponding 4-year survival rates were 56.7 and 88.0%, respectively. The incidence of peripheral artery disease was significantly higher in the dialysis group. Uremic patients showed significantly lower hemoglobin serum levels at the time of admission compared to the control group (11.4 +/- 1.62 vs. 13.3 +/- 1.81 mg/dl). These patients received significantly higher numbers of blood transfusions (6.7 +/- 5.6 vs. 2.75 +/- 3.8), and platelet transfusions.

CONCLUSION

Our preliminary study indicates that coronary surgery can be performed with acceptable mid-term results when the specific requirements of this patient group are taken into account.

Impact of renal dysfunction on outcomes of coronary artery bypass surgery: results from the Society of Thoracic Surgeons National Adult Cardiac Database

BACKGROUND

Although patients with end-stage renal disease are known to be at high risk for mortality after coronary artery bypass graft (CABG) surgery, the impact of lesser degrees of renal impairment has not been well studied. The purpose of this study was to compare outcomes in patients undergoing CABG with a range from normal renal function to dependence on dialysis.

METHODS AND RESULTS

We reviewed 483,914 patients receiving isolated CABG from July 2000 to December 2003, using the Society of Thoracic Surgeons National Adult Cardiac Database. Glomerular filtration rate (GFR) was estimated for patients with the use of the Modification of Diet in Renal Disease study formula. Multivariable logistic regression was used to determine the association of GFR with operative mortality and morbidities (stroke, reoperation, deep sternal infection, ventilation >48 hours, postoperative stay >2 weeks) after adjustment for 27 other known clinical risk factors. Preoperative renal dysfunction (RD) was common among CABG patients, with 51% having mild RD (GFR 60 to 90 mL/min per 1.73 m2, excludes dialysis), 24% moderate RD (GFR 30 to 59 mL/min per 1.73 m2, excludes dialysis), 2% severe RD (GFR <30 mL/min per 1.73 m2, excludes dialysis), and 1.5% requiring dialysis. Operative mortality rose inversely with declining renal function, from 1.3% for those with normal renal function to 9.3% for patients with severe RD not on dialysis and 9.0% for those who were dialysis dependent. After adjustment for other covariates, preoperative GFR was one of the most powerful predictors of operative mortality and morbidities.

CONCLUSIONS

Preoperative RD is common in the CABG population and carries important prognostic importance. Assessment of preoperative renal function should be incorporated into clinical risk assessment and prediction models.

Association of Renal Insufficiency With In-Hospital Mortality Among Japanese Patients With Acute Myocardial Infarction Undergoing Percutaneous Coronary Interventions

It is not yet clear whether a difference in in-hospital morality between patients with and without renal insufficiency undergoing percutaneous coronary intervention (PCI) exists. Therefore, the aim of the present study was to investigate if such as association exists in Japan. Data from the Tokai Acute Myocardial Infarction Study II were used. This was a prospective study of all 3274 patients admitted with acute myocardial infarction (AMI) to the 15 participating hospitals from 2001 to 2003. We abstracted the baseline and procedural characteristics as well as in-hospital mortality from detailed chart reviews. Patients were stratified into 2 groups according to the estimated creatinine clearance on admission. The creatinine clearance values were available in 2116, 107 of whom had renal insufficiency. The patients with renal insufficiency were more likely to be older, female, not independent in their daily activities, have lower body mass index and higher heart rate values on admission, lower prevalences of hypercholesterolemia and peptic ulcers, greater prevalences of diabetes, angina, previous heart failure, previous renal failure, previous cerebrovascular disease, aortic aneurysm, worse clinical course such as bleeding, and a multivessel coronary disease. Vasopressors, an intra-aortic balloon pump, and mechanical ventilation were frequently used in the patients with renal insufficiency, while thrombolytics were used less frequently. The patients with renal insufficiency had a higher in-hospital mortality rate than those without. Multivariate analysis identified renal insufficiency as an independent predictor of in-hospital death. The results suggest that renal insufficiency is an independent predictor of in-hospital death among AMI patients undergoing PCI.

Impact of renal insufficiency on outcome after contemporary percutaneous coronary intervention

BACKGROUND

End-stage renal failure is associated with poor outcomes, including increased mortality, after percutaneous coronary intervention (PCI). The effect of milder degrees of renal insufficiency (RI) is less clear, especially with routine stenting and glycoprotein IIb/IIIa inhibitor therapy, which may be of particular benefit in patients with RI.

METHODS

Clinical, angiographic, procedural, and outcome variables of 7769 consecutive patients who underwent PCI between April 2000 and July 2004 were entered into a prospective database. Inhospital mortality and morbidity were calculated according to baseline creatinine clearance. Simple and multiple logistic regression analyses were performed to determine independent predictors of mortality.

RESULTS

Baseline creatinine clearance was available in 6840 patients. It was normal (> 80 mL/min) in 3474; 1670 had mild RI (61-80 mL/min), 1111 moderate RI (41-60 mL/min), and 585 severe RI (< or = 40 mL/min). Major adverse cardiac events (MACE) (death/myocardial infarction/revascularization) increased substantially with worsening renal function (2.4% vs 3.0% vs 4.8% vs 9.7%, P < .0001), as did mortality (0.3% vs 0.7% vs 1.5% vs 6.0%, P < .0001). Multiple logistic regression analysis identified moderate RI and severe RI as independent predictors of mortality (odds ratio [OR] 3.9, P < .001; OR 12.7, P < .0001, respectively) and morbidity (MACE) (OR 1.5, P < .05; OR 2.5, P < .0001, respectively). Mild RI trended to increase the risk of mortality but did not reach statistical significance as an independent predictor of inhospital death on multiple regression analysis (OR 2.1, P = .1) and did not increase the risk of MACE (OR 1.1, P = .6).

CONCLUSIONS

Despite routine stenting and glycoprotein IIb/IIIa inhibitor therapy, RI remains an independent predictor of increased morbidity, and particularly mortality, after PCI. However, the adverse effect of truly mild RI on outcome is limited.

Impact of moderate renal insufficiency on restenosis and adverse clinical events after paclitaxel-eluting and bare metal stent implantation: results from the TAXUS-IV Trial

BACKGROUND

Mortality and restenosis may be increased in patients with mild to moderate renal insufficiency (RI) after coronary stent implantation. Whether drug-eluting stents safely reduce restenosis and enhance event-free survival in these patients is unknown. We sought to evaluate the impact of baseline RI on clinical and angiographic outcomes in patients undergoing elective percutaneous coronary intervention using either bare metal or paclitaxel-eluting stents.

METHODS

In the TAXUS-IV trial, 1314 patients were randomized to either the polymer-based paclitaxel-eluting TAXUS stent or an identical-appearing bare metal stent. Outcomes were stratified on the basis of the presence of RI, defined as a baseline creatinine clearance < 60 cm3/min calculated by the Cockcroft-Gault formula.

RESULTS

Baseline RI was present in 223 (17.2%) patients, in whom the mean creatinine clearance was 49.6 +/- 8.5 cm3/min. Compared with bare metal stents, treatment with the TAXUS stent resulted in lower rates of 9-month angiographic restenosis rates in both patients with (2.1% vs 20.5%, P = .009) and without (9.2% vs 27.8%, P < .0001) baseline RI. Similarly, 1-year target lesion revascularization rates were reduced with the TAXUS stent in patients with (3.3% vs 12.2%, P = .01) and without (4.7% vs 15.8%, P < .0001) baseline RI. The occurrence of death, myocardial infarction, and stent thrombosis at 1 year were similar in both randomization groups, independent of renal function.

CONCLUSIONS

The polymer-based paclitaxel-eluting TAXUS stent safely reduces clinical and angiographic restenosis in patients with preserved as well as moderate impairment of baseline renal function.

Coronary surgery in dialysis-dependent patients with end stage renal failure

The number of patients with dialysis-dependent end stage renal failure (ESRF) and coronary heart disease (CAD) has increased in recent years. Coronary artery bypass grafting (CABG) has become the standard treatment for CAD in this patient group, but is still considered as a risk procedure due to increased mortality and morbidity. In a retrospective study we analyzed our clinical results of isolated CABG in 40 dialysis-dependent patients with ESRF (5 female and 35 male, mean age 65+/-8.4 years) and the use of extracorporeal circulation. The perioperative control group comprised 51 patients (10 female and 41 male, mean age 67+/-7.3 years) with normal renal function and isolated CABG. Demographic and preoperative data were comparable in both groups. Hospital mortality was 2.5% in patients with ESRF and 0% in patients with normal renal function. Morbidity was comparable in both groups. The mean number of grafts was 3.1+/-0.9 in the dialysis group and 2.9+/-0.8 in the control group. In the follow-up of the dialysis group (34+/-23 months) 8 patients died. CABG in patients with dialysis-dependent ESRF can be performed with good clinical results and morbidity comparable to patients with normal renal function.

Long-Term Outcome After Coronary Angioplasty in Renal Transplant and Hemodialysis Patients

In order to determine how renal transplantation modifies in hospital and long-term outcome after coronary angioplasty, we compared dialysis and renal transplant patients with control patients without renal failure. Seventy-five consecutive dialysis patients (group D) and 37 renal transplant patients (group T) undergoing coronary angioplasty, were compared with two control groups (groups control D and control T, respectively) matched 1:1 with groups D and T for clinical and angiographic characteristics. The mean follow-up was 50 months. The rate of angiographic success was high and comparable in the four groups (P=0.7). Renal transplant patients were younger than dialysis non-transplant patients (P=0.004). The risk of 4-year cardiac death and nonfatal myocardial infarction was higher in dialysis compared to control dialysis patients (OR 2.6, 95% CI 1.35--5.01, P=0.004), in transplant patients compared to control transplant patients (OR 9.93, 95% CI 1.17--84.04, P=0.03), and there was a trend toward a higher risk in dialysis than in renal transplant patients (OR 1.6, 95% CI 0.8--3.19, P=0.08). The risk of 4-year mortality was higher in dialysis patients than in the other three groups (31% in group D versus 19% in group T, 13% in group control D, and 0% in group control T, P<0.001). After adjusting for age, diabetes, and multivessel disease, long-term mortality risk was similar in dialysis and renal transplant patients. On multivariate analysis, renal function (P=0.002), age (P=0.005), and tobacco consumption (P=0.005) were independently associated with 4-year cardiac death. In patients with end-stage renal disease who undergo coronary angioplasty, renal transplantation was not independently associated with a lower long-term mortality compared to dialysis treatment. Both dialysis and renal transplant patients show lower survival rates compared to matched control patients.

The Outcome of Cardiac Surgery in Dialysis-Dependent Patients

BACKGROUND

Patients on dialysis for end-stage renal failure (ESRF) are undergoing cardiac surgery with increasing frequency. Furthermore, ESRF is known to be an important risk factor for complications of cardiac operations performed with cardiopulmonary bypass.

AIMS

To evaluate the outcome of dialysis-dependent patients undergoing cardiac surgery at one institution.

METHODS

A retrospective analysis was performed on consecutive patients with ESRF dependent upon maintenance haemodialysis or peritoneal dialysis who underwent cardiac surgery from January 1998 to August 2002.

RESULTS

Thirty-eight patients on dialysis underwent cardiac surgery during this time period (1.5% of total cases). The most common cause for ESRF was diabetic nephropathy (n = 12). Operations performed included isolated coronary artery bypass grafting (CABG, n = 22), CABG and valve surgery (n = 8), and valve surgery alone (n = 6). When allowing for age, sex, surgeon and operative category, the odds ratio for mortality risk of dialysis patients, compared with all others, was 4.9 (95% confidence interval (CI): 1.7-13.9, p = 0.003), and for morbidity risk, was 2.8 (95% CI: 1.4-5.4, p = 0.003).

CONCLUSIONS

Patients on dialysis have an increased morbidity and mortality following cardiac surgery, however we believe ESRF should not be regarded as an absolute contraindication to cardiac surgery or cardiopulmonary bypass.

Outcome of Coronary Artery Bypass Operations in Patients With Renal Insufficiency With and Without Renal Transplantation

HYPOTHESIS

Renal insufficiency (RI) is associated with an increased risk of morbidity and mortality following coronary artery bypass graft (CABG) operations, particularly among patients who are dependent on dialysis.

DESIGN AND SETTING

A retrospective analysis of data collected at a tertiary care center.

PATIENTS

One hundred eighty-four consecutive patients with RI who underwent CABG surgery between 1992 and 2004. This group consisted of 152 patients with serum creatinine levels of > or = 1.7 mg/dL (group I) and 32 kidney transplant recipients (group II). Of the patients in group I, 90 were dialysis-free (subgroup IA) and 62 were dialysis-dependent (subgroup IB).

MAIN OUTCOME MEASURES

Demographics, perioperative data, and outcomes for each of the three groups were evaluated and compared.

RESULTS

Fifty-four percent of the patients were in New York Heart Association classes III and IV, 36% had unstable angina, and 21% had left main coronary disease. The mean ejection fraction was 38%. The median postoperative length of stay in the hospital was 10 days. Of the patients in group IB, 8% required reexploration for bleeding compared to 3% in groups IA and II (p < 0.05). Dialysis was needed postoperatively in five patients in group IA and two patients in group II (5.7%). The raw operative mortality rate was 7.6% and was higher in group IB (9.7%) compared to groups IA and II (6.7% and 6.2%, respectively; p < 0.05). The actuarial 5-year survival rate was higher in group II compared to group I (79% vs 59%, respectively; p < 0.05). The difference in survival rates was more apparent between groups II and IB (79% vs 57%, respectively; p < 0.005).

CONCLUSIONS

CABG is associated with an increased rate of perioperative complications and mortality in patients with RI. Dialysis dependence is a major risk factor for patients undergoing CABG surgery. However, with acceptable surgical results, dialysis patients should not be denied CABG surgery. A survival advantage is demonstrated among patients with previous kidney transplants compared to those patients who are dependent on dialysis.

Non-dialysis-dependent renal dysfunction and cardiac surgery-an assessment of perioperative risk factors

OBJECTIVE

In most reports, dialysis-dependent patients are known to be at increased risk for perioperative morbidity and mortality after cardiac surgical procedures.(1-7) However, the preoperative factors important for risk stratification of patients who have renal insufficiency but are not dialysis dependent are unclear. We set forth to ascertain preoperative risk factors important for predicting 2 endpoints: (1) dialysis at discharge and (2) hospital death.

DESIGN

A retrospective analysis.

SETTING

A tertiary referral center.

PATIENTS

From a database of patients undergoing cardiopulmonary bypass over a 6-year period, 150 patients were chosen for study based on their preoperative creatinine being greater than 1.5 mg/dl.

INTERVENTIONS

Routine monitoring and care of patients after their cardiac surgical procedures.

MEASUREMENTS AND MAIN RESULTS

Many preoperative, perioperative, and postoperative variables were measured. Multivariable regression was used for data analysis. There were 21 (14%) hospital deaths and 7 (5%) patients who were not on preoperative dialysis who required dialysis at discharge. Preoperative risk factors for hospital death were the patients' New York Heart Association (NYHA) class (p = 0.004) and emergency status (p = 0.005). Preoperative risk factors for dialysis at discharge were female gender (p = 0.02), emergency status of procedure (p = 0.01), and preoperative creatinine (p = 0.03).

CONCLUSIONS

These data allow for a more accurate assessment of risk stratification in this group of patients with renal insufficiency but who are not dependent on dialysis. Given the data presented here and other studies that report good outcomes for patients with renal disease after cardiac surgical procedures,(8-10) earlier operative intervention for coronary disease in this subset of patients might be warranted.

Association of chronic kidney disease with clinical outcomes after coronary revascularization: the Arterial Revascularization Therapies Study (ARTS)

BACKGROUND

Chronic kidney disease (CKD) is associated with adverse outcomes after coronary artery bypass graft surgery (CABG) and percutaneous coronary interventions (PCI), but it is unclear which of these revascularization strategies is associated with lower risk for morbidity and mortality in this population. In the Arterial Revascularization Therapies Study (ARTS), we compared long-term clinical outcomes after CABG or PCI with multivessel stenting in patients with CKD.

METHODS

The ARTS randomly assigned 1205 participants with and without CKD to CABG or PCI with multivessel stenting. We defined CKD as creatinine clearance < or =60 mL/min, estimated by the Cockroft-Gault equation. The primary outcome was the composite of death, myocardial infarction (MI), or stroke; and, a secondary outcome was repeat revascularization. Participants were followed for a mean of 3 years after their intervention. We evaluated whether randomization to CABG or PCI was associated with different outcomes among participants with CKD.

RESULTS

Two hundred ninety participants (25%) had CKD at entry into ARTS. One hundred fifty-one received PCI, and 139 received CABG. No difference was observed in the primary endpoint with CABG or PCI among CKD participants (adjusted Hazard Ratio [HR] CABG vs PCI = 0.93; 95% CI 0.54-1.60; P = .97). However, CABG was associated with a reduced risk for repeat revascularization (HR = 0.28; 95% CI 0.14-0.54; P < .01). Compared with participants with normal renal function, CKD was associated with a nearly 2-fold risk for the primary outcome (unadjusted HR = 1.9; 95% CI 1.4-2.7; P < .01). After multivariate adjustment, this association remained significant (HR 1.6; 95% CI 1.1-2.4).

CONCLUSIONS

In patients with multivessel CAD and CKD, treatment with CABG or PCI with multivessel stenting led to similar outcomes of death, MI, or stroke, but CABG was associated with decreased repeat revascularizations. When compared with ARTS participants with normal renal function, those with CKD had substantially elevated risk of adverse clinical outcomes after coronary revascularization.

The renal patient with coronary artery disease

The patient with chronic kidney disease and coronary artery disease (CAD) presents special challenges. This report reviews the scope of the challenge, the hostile internal milieu predisposing to CAD and cardiac events, management issues, unresolved dilemmas, and the need for randomized trials to allow for evidence-based treatment.

Atherosclerosis in Dialyzed Patients

In the recent HEMO study, the most common cause of death in dialyzed patients was ischemic heart disease. In Europe there are regional differences, but the mortality due to cardiovascular disease is also very high. The long-lasting controversy whether the high incidence and prevalence of atherosclerotic manifestations (particularly ischemic heart disease) may be explained by known risk factors, or non-traditional risk factors are also involved seems to be partially solved with the increasing evidence that the latter hypothesis is true. Thus, together with classic risk factors such as hypertension, dyslipidemia and diabetes, other situations such as microinflammation, increased concentration of asymmetrical dimethyl-L-arginine, disturbed phosphate metabolism and anemia may represent important risk factors for accelerated atherosclerosis in dialyzed patients.