Predictors for Early and Late Outcomes After Coronary Artery Bypass Grafting in Hemodialysis Patients

Coronary artery bypass grafting in dialysis patients: a propensity score-matched analysis

BACKGROUND

Patients undergoing dialysis treatment have long been recognized as having an elevated risk of developing coronary artery disease necessitating coronary artery bypass grafting (CABG). However, the prognostic implications of CABG in dialysis-dependent patients remain underexplored. This study aimed to comprehensively assess both short- and long-term outcomes in dialysis-dependent patients undergoing CABG.

METHODS

In this retrospective analysis, we meticulously matched 55 dialysis-dependent patients with 55 non-dialysis patients, controlling for baseline characteristics including age, sex, etiology, and date of surgery. All patients underwent CABG treatment at our institution between January 2014 and June 2022. We conducted a comparative analysis of postoperative complications and survival rates between the two groups.

RESULTS

Our findings revealed that the dialysis-dependent group exhibited a significantly higher incidence of postoperative complications compared to the non-dialysis group (92.7% vs. 61.8%; p < 0.001). Furthermore, the 5-year survival rates were notably diminished among dialysis patients relative to their non-dialysis counterparts (46.2 ± 7.9% vs. 58.2 ± 12.1%, p = 0.045). Consistently, dialysis patients exhibited decreased 5-year cardiac-event-free rates in contrast to non-dialysis patients (31.6 ± 7.6% vs. 58.8 ± 11.3%, p = 0.041). Predictably, several baseline parameters were identified as significant risk factors contributing to adverse outcomes among dialysis patients, including a history of smoking, diabetes mellitus, congestive heart failure upon admission, and the requirement for intraoperative concomitant surgery (p = 0.006, p = 0.043, p = 0.017, p = 0.003, respectively).

CONCLUSIONS

This study underscores the poorer prognosis associated with CABG treatment in dialysis-dependent patients. Notably, baseline factors such as a smoking history, diabetes mellitus, congestive heart failure upon admission, and the need for intraoperative concomitant surgery were all independently linked to increased mortality in this patient population.

Coronary Artery Bypass Grafting in Dialysis-Dependent Patients - Key Peri-Operative Considerations

Cardiovascular disease represents the leading cause of mortality in dialysis-dependent (DD) patients, with the great majority of these patients afflicted by severe coronary artery disease. As rates of end-stage renal disease increase worldwide, DD patients represent a growing proportion of the coronary artery bypass grafting (CABG) cohort. Yet, these patients are complex, with crucial changes in their haemodynamic and physiologic profiles that complicate revascularisation surgery. First, this comprehensive literature review explores the outcomes and prognostic factors for DD patients undergoing CABG. We then summarise the intricacies relating to important peri-operative decisions such as use of cardio-pulmonary bypass and choice of conduit.

Clinical outcomes after coronary artery bypass grafting in patients with dialysis-dependent end-stage renal disease and an analysis of the related influencing factors

Perioperative and short/mid-term survival rates of dialysis-dependent patients with end-stage renal disease (ESRD), who undergo coronary artery bypass grafting (CABG), and the factors influencing mortality are not well evaluated In China. We retrospectively analyzed the perioperative and postoperative 1-, 3-, and 5-year survival rates of 53 dialysis-dependent ESRD patients who underwent CABG, and compared the factors related to perioperative mortality and all-cause mortality during the postoperative follow-up. Survival rates were expressed as Kaplan-Meier survival curves, and factors influencing the follow-up survival rates were analyzed using the log rank (Mantel-Cox) test. There were eight perioperative deaths, resulting in 15.1% mortality. Intraoperative intra-aortic balloon pump use (P = 0.01), advanced age (P = 0.0027), and high EuroSCORE II score (P = 0.047) were associated with increased perioperative mortality. Forty-five discharged patients were followed from 2 months to 10 years (median, 4.2 years) postoperatively. There were 19 all-cause deaths, including 10 cardiac deaths (10/19, 52.6%). Comparisons between groups indicated that the presence of peripheral artery disease (PAD) increased mortality during follow-up (P = 0.025); 1-, 3-, and 5-year survival rates were 93.3, 79.5, and 66.8%, respectively. The results of the long-rank analysis indicated that the presence of PAD was a risk factor for postoperative survival (log rank χ² = 4.543; P = 0.033). Dialysis-dependent patients with ESRD had high perioperative mortality and unsatisfactory short- and medium-term survival after CABG. PAD was a risk factor affecting patients' postoperative survival. Multidisciplinary teamwork is needed to enhance postoperative management and reduce complications, to improve postoperative survival in these patients.

Should Bilateral Internal Thoracic Arteries be Used in Patients with Chronic Kidney Disease?

Preoperative renal dysfunction is a major determinant of operative and long-term mortality following cardiac surgery. The objective of this study was to assess early and long-term results of CABG in patients with preoperative chronic kidney disease (CKD) using a bilateral internal thoracic artery (BITA) strategy, compared to those without CKD. We retrospectively analyzed data for 2,111 consecutive patients who underwent CABG with BITA between 2000 and 2019. One-to-many propensity score matching was performed to produce a cohort of 132 patients with CKD (defined as an estimated glomerular filtration rate <60 mL/min/1.73 m2), matched to 358 patients with normal renal function (non-CKD). The primary end-point of interest was late freedom from all-cause mortality. Late hospital readmissions were also assessed. Mean eGFR and serum creatinine were: 49.8 versus 84.3 mL/min/m2 and 146.1 versus 83.6 µmol/L (CKD vs non-CKD, P< 0.001). In-hospital outcomes were similar among matched patients, including mortality (CKD 0.8% vs non-CKD 0%, P= 0.31). At a median follow-up of 6.9 years, there was no significant difference in survival between both groups (hazard ratio (HR) 1.37, 95% confidence interval (CI) 0.87-2.16, P= 0.17). Hospital readmission for cardiovascular causes (including repeat coronary revascularization) was comparable between the 2 groups. However, the risk of hospital readmission for renal causes was higher in patients with CKD (6.7%) compared to non-CKD (1.2%). In a propensity score-matched cohort of patients undergoing BITA-CABG, CKD was not associated with increased early or late mortality, nor was there a greater risk of hospital readmission for cardiovascular events.

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.

Long-term prognosis in patients with end-stage renal disease after coronary artery bypass grafting

Background

Cardiovascular disease is a major cause of morbidity and mortality in patients with end-stage renal disease (ESRD). Coronary artery bypass grafting (CABG) is beneficial in selected patients with ESRD. This study investigates the survival outcomes and prognostic factors in ESRD patients who underwent CABG.

Methods

A retrospective analysis was performed for 149 patients with ESRD who underwent isolated CABG between 2006 and 2015.

Results

Mean age was 59.4±8.7 years and 106 patients (71.1%) were male. Operative mortality occurred in 20 patients (13.4%). Overall survival was 81.1%±3.2% at 1 year, 41.5%±4.3% at 5 years and 19.2%±4.2% at 10 years. Median survival was 4.3 years. Multivariable analysis identified age [P=0.001, odds ratio (OR): 1.15 per 1-year increase, 95% confidence interval (CI): 1.06-1.25], preoperative left ventricular ejection fraction (LVEF) (P=0.020, OR: 0.94, 95% CI: 0.89-0.99) and non-elective status of operation (P=0.049, OR: 3.34, 95% CI: 1.00-11.1) as predictors of operative mortality. Cox regression analysis identified age [P<0.001, hazard ratio (HR): 1.05 per 1-year increase, 95% CI: 1.03-1.08], New York Heart Association (NYHA) class III or IV status (P=0.010, HR: 1.75, 95% CI: 1.15-2.67) and the use of a left internal mammary artery (LIMA) to left anterior descending artery (LIMA-LAD) graft (P=0.029, HR: 0.42, 95% CI: 0.19-0.92) as factors influencing long-term survival.

Conclusions

CABG is associated with high operative mortality and poor long-term survival in ESRD patients. Age and NYHA class influenced late survival. LIMA-LAD grafting conferred a long-term survival advantage.

Hospital costs and prognosis in end-stage renal disease patients receiving coronary artery bypass grafting

Background

Coronary artery disease is common in patients with end-stage renal disease (ESRD). Patients with ESRD are a high-risk group for cardiac surgery and have increased morbidity and mortality. Most studies comparing ESRD patients receiving coronary artery bypass grafting (CABG) or percutaneous coronary intervention have found that the long-term survival is good in ESRD patients after CABG. The aim of our study was to compare ESRD patients who underwent CABG with the general population who underwent CABG, in terms of prognosis and hospital costs.

Methods

This study analyzed data from the National Health Insurance Research Database in Taiwan for patients who were diagnosed with ESRD and received CABG (ICD-9-CM codes 585 or 586) between January 1, 2004, and December 31, 2009. The ESRD patients included in this study all received catastrophic illness cards with the major illness listed as ESRD from the Ministry of Health and Welfare in Taiwan.

The control subjects were randomly selected patients without ESRD after propensity score matching with ESRD patients according to age, gender, and comorbidities at a 2:1 ratio from the same dataset.

Results

A total of 48 ESRD patients received CABG, and their mean age was 62.04 ± 10.04 years. Of these patients, 29.2% were aged ≥70 years, and 66.7% were male. ESRD patients had marginally higher intensive care unit (ICU) stays (11.06 vs 7.24 days) and significantly higher ICU costs (28,750 vs 17,990 New Taiwan Dollars (NTD)) than non-ESRD patients. Similarly, ESRD patients had significantly higher surgical costs (565,200 vs. 421,890 NTD), a higher perioperative mortality proportion (10.4% vs 2.1%) and a higher postoperative mortality proportion (33.3% vs 11.5%) than non-ESRD patients.

Conclusions

After CABG, ESRD patients had a higher risk of mortality than non-ESRD patients, and ICU and surgery costs were also higher among the ESRD patients than among patients without ESRD.

Post-Coronary Artery Bypass Medications in Dialysis Patients: Do We Need to Change Strategies?

BACKGROUND

Coronary artery bypass grafting (CABG) is frequently performed in patients with end-stage renal disease (ESRD) together with severe coronary artery disease, after which, patients with ESRD have higher surgical risk and poorer long-term outcomes. We report our experience in patients with ESRD who survived in CABG and identify predictors of long-term outcomes.

METHODS

We retrospectively investigated 93 consecutive patients with ESRD who survived to discharge after isolated CABG between January 2005 and December 2016 at our institution. Long-term outcomes, including all-cause mortality after discharge, readmission due to major adverse cardiac events, and reintervention, were evaluated. Predictors affecting long-term outcomes were also analyzed.

RESULTS

The rates of freedom from all-cause mortality after discharge in 1, 3, 5, and 10 years were 92.1, 81.3, 71.9, and 34.9%, respectively. The rates of freedom from readmission due to major adverse cardiac events in 1, 3, 5, and 10 years were 90.7, 79.1, 69.9, and 55.6%, respectively. The rates of freedom from reintervention in 1, 3, 5, and 10 years were 95.3, 86.5, 79.0, and 66.6%, respectively. Postoperative β-blocker and statin use significantly improved overall long-term survival (β-blocker, p = 0.013; statin, p = 0.009). After case-control matching, patients who received statins showed better long-term survival than those without statins. The comparison of long-term survival between patients with and without β-blockers showed no significant difference after matching.

CONCLUSIONS

After CABG, dialysis patients who survived to discharge had acceptable long-term overall survival. Post-CABG statin use in dialysis patients is a predictor of better long-term survival.

Outcomes in patients with solid organ transplants undergoing cardiac surgery

OBJECTIVE

Long-term outcomes after cardiac surgery in solid organ transplant recipients are limited in the contemporary literature. The objective of this study is to evaluate postoperative outcomes in these patients, including variables associated with mortality and readmissions.

METHODS

All adults undergoing isolated coronary artery bypass grafting, isolated valve, or coronary artery bypass grafting + valve cardiac surgical procedures from 2011 to 2018 were included in this study. Patients with solid organ transplants undergoing cardiac surgery were studied. Primary outcomes included operative (30-day) and 5-year mortality.

RESULTS

A total of 11,190 patients underwent isolated coronary artery bypass grafting, isolated valve, or coronary artery bypass grafting + valve operations at our institution from 2011 to 2018. Of these, 129 patients (1%) had solid organ transplants and underwent isolated coronary artery bypass grafting (n = 84), isolated valve (n = 30), or coronary artery bypass grafting + valve (n = 15). Type of organ transplant included 84 patients (65%) with kidney, 27 patients (21%) with liver, 9 patients (7%) with heart, and 9 patients (7%) with lung transplants. The median Society of Thoracic Surgeons Predicted Risk Of Mortality for the cohort was 2.73 (Q1-Q3: 1.67-6.33). Three patients (2%) had an operative (30-day) mortality. Significant variables associated with 5-year mortality on multivariable Cox regression analysis included chronic obstructive pulmonary disease (hazard ratio, 2.44; 1.01-5.90; P = .048) and congestive heart failure (hazard ratio, 4.45; 1.81-10.9; P = .001). Significant variables associated with 5-year readmissions included chronic obstructive pulmonary disease, dialysis dependence, and concomittant valve surgery with coronary artery bypass grafting. Five-year readmission rate was 88%, and patients with valve operations (± coronary artery bypass grafting) had significantly lower (P = .009) freedom from readmission (6%).

CONCLUSIONS

Cardiac surgery can be performed with low operative mortality and good long-term survival in patients with solid organ transplants. Five-year hospital readmissions are common, with significantly more readmissions in patients who had valve procedures.

Outcomes of cardiovascular surgery for chronic dialysis patients in current Japan

Background

The number of dialysis patients in Japan is rising, with an increasing number requiring cardiovascular surgery.

Methods

We investigated the short- and long-term outcomes in 70 dialysis patients among a total of 1124 who underwent cardiovascular surgery in our hospital between 2004 and 2016. We investigated outcomes following open surgery and identified factors that affected the prognosis. We also compared the long-term survival rate with the survival rate of the Japanese dialysis population.

Results

The long-term survival rate was 70.6%, 51.1%, and 19.2% after 3, 5, and 10 years, respectively. The causes of long-term death were heart disease in 8 patients, cerebrovascular disease in 7, cachexia in 3, infection in 2, and other causes in 3. The freedom from cardiac death was 88.7%, 77.9%, and 54.9% after 3, 5, and 10 years, respectively. Multivariate analysis using Cox’s proportional hazard model showed that a history of atherosclerosis obliterans (hazard ratio 5.4, p = 0.05) and mediastinitis (hazard ratio 10.2, p = 0.03) were risk factors for death in long-term follow-up, and a history of atherosclerosis obliterans was an independent risk factor for cardiac death in long-term follow-up (hazard ratio 5.3, p = 0.01). Five-year survival of the study subjects was comparable to that of the Japanese dialysis population.

Conclusions

The prognosis for dialysis patients after open surgery was equivalent to that of Japanese dialysis patients in general. A high proportion of late postoperative deaths were due to heart disease. Patients with atherosclerosis obliterans had a poor prognosis.

Effects of upper-extremity vascular access creation on cardiac events in patients undergoing coronary artery bypass grafting

The present study was conducted to investigate whether upper-extremity vascular access (VA) creation increases the risk for major adverse cardiac events (MACE) and death in patients undergoing coronary artery bypass grafting (CABG) with an in situ left internal thoracic artery (ITA) graft. A total of 111 patients with CABG with a left ITA graft who underwent upper-extremity VA creation were analyzed retrospectively; 93 patients received left VA creation (83.8%, ipsilateral group) and 18 patients received right VA creation (16.2%, contralateral group). The primary outcome was the occurrence of MACE, and the secondary outcome was the composite of MACE or late death. There were no significant differences in the incidence of primary (P = 0.30) or secondary (P = 0.09) outcomes between the two groups. Multivariate regression analysis indicated that prior cerebrovascular accidents (hazard ratio [HR] 3.30; 95% confidence interval [CI] 1.37–7.97; P = 0.01) and type of VA (HR 3.44; 95% CI 1.34–8.82; P = 0.01) were independently associated with MACE; prior peripheral arterial occlusive disease (HR 4.22; 95% CI 1.62–10.98; P<0.01) and type of VA (arteriovenous fistula vs. prosthetic arteriovenous grafting) (HR 3.06; 95% CI, 1.42–6.61; P<0.01) were associated with the composite of MACE or death. The side and location of VA were not associated with MACE or death. Our study showed no definite evidence that ipsilateral VA creation affects the subsequent occurrence of MACE or late death from any cause. The type of VA (a prosthetic arteriovenous grafting) is a significant predictor of the subsequent occurrence of MACE or late death.

Coronary Artery Bypass Surgery in End-Stage Renal Disease Patients

The number of patients requiring hemodialysis is continuously increasing around the world. Hemodialysis affects patient quality of life and it is also associated with a higher risk for cardiovascular events. In addition to traditional risk factors for cardiovascular events such as hypertension, hyperlipidemia, and diabetes, hemodialysis is associated with hyperphosphatemia, chronic inflammation, vascular calcification, and anemia which accelerate atherosclerosis, vascular stiffness, and cardiac ischemia. Treatment strategy for coronary revascularization in this progressive disease remains controversial. However, a systematic treatment including medical therapy and complete revascularization through a less invasive strategy should be considered in addressing this problem. This review discusses the epidemiology, vascular pathology and current treatment options in patients with end-stage renal disease requiring coronary revascularization.

Effect of hemodialysis access blood flow on cardiac events after coronary artery bypass grafting using an internal thoracic artery

Background

The possibility of coronary steal through an arteriovenous fistula (AVF) in hemodialysis (HD) patients with coronary artery bypass grafts (CABGs) using an ipsilateral internal thoracic artery (ITA) has been suggested. In order to define the significance of such a possibility, we analyzed cardiac events and mortality risk in patients in relation to AVF flow.

Methods

A retrospective cohort study was performed on prevalent HD patients from a single center. The outcomes included a first cardiac event, cardiac death and death from any cause.

Results

The group consisted of 23 chronic HD patients having ITA CABG and upper extremity AV access, 12 patients had an ipsilateral and 11 patients had a contralateral location of ITA CABG and an upper extremity AV access. The mean follow-up period was for 37.0 months. Multivariable Cox proportional-hazards regression analysis of risk of death from any cause in relation to AV access flow showed no increased risk, neither in the group with ipsilateral location of ITA grafts and dialysis accesses (adjusted HR, 3.047 [95% CI, 0.996 to 1.000], p = 0.081), nor in the group with contralateral location of both shunts (adjusted HR, 0.173 [95% CI, 0.997 to 1.002], p = 0.678). There was no significant correlation between AV access blood flow and the risk of first cardiac event as well as cardiac death in either study group.

Conclusions

In this study on HD patients having ipsilateral ITA CABG and AVF, fistula flow rate was not found to be associated with mortality or cardiac risk.

Efficacy of Carperitide in Hemodialysis Patients Undergoing Cardiac Surgery

PURPOSE

Recently, performance of cardiac surgery in hemodialysis patients has increased, but the mortality rate is high.

METHODS

We retrospectively examined the early and long-term outcomes in 128 dialysis patients who underwent cardiac surgery with or without carperitide infusion and were followed for 2 years. Sixty-three patients received carperitide infusion during surgery and 65 patients did not.

RESULTS

The hospital mortality rate was 1.6% in the carperitide group and 12.3% in the non-carperitide group, being significantly lower in the carperitide group. The 2-year actuarial survival rate was 90.5% ± 3.7% in the carperitide group, and 76.9% ± 5.2% in the non-carperitide group, while the major adverse cardiovascular and cerebrovascular events (MACCE)-free rate at 2 years postoperatively was 90.5% ± 3.7% in the carperitide group and 67.7% ± 5.8% in the non-carperitide group.

CONCLUSIONS

These findings suggest that carperitide improves the early postoperative outcome in dialysis patients undergoing cardiac surgery, as has already been demonstrated in non-dialysis patients. An early postoperative cardioprotective effect of carperitide and improvement of renal function in oliguric patients might have contributed to this outcome. However, this was a retrospective study, so a prospective investigation is required to demonstrate the mechanisms involved. In addition, further evaluation of the long-term results would be desirable.

Long-Term Post-CABG Survival: Performance of Clinical Risk Models Versus Actuarial Predictions

BACKGROUND/AIM

Clinical risk models are commonly used to predict short-term coronary artery bypass grafting (CABG) mortality but are less commonly used to predict long-term mortality. The added value of long-term mortality clinical risk models over traditional actuarial models has not been evaluated. To address this, the predictive performance of a long-term clinical risk model was compared with that of an actuarial model to identify the clinical variable(s) most responsible for any differences observed.

METHODS

Long-term mortality for 1028 CABG patients was estimated using the Hannan New York State clinical risk model and an actuarial model (based on age, gender, and race/ethnicity). Vital status was assessed using the Social Security Death Index. Observed/expected (O/E) ratios were calculated, and the models' predictive performances were compared using a nested c-index approach. Linear regression analyses identified the subgroup of risk factors driving the differences observed.

RESULTS

Mortality rates were 3%, 9%, and 17% at one-, three-, and five years, respectively (median follow-up: five years). The clinical risk model provided more accurate predictions. Greater divergence between model estimates occurred with increasing long-term mortality risk, with baseline renal dysfunction identified as a particularly important driver of these differences.

CONCLUSIONS

Long-term mortality clinical risk models provide enhanced predictive power compared to actuarial models. Using the Hannan risk model, a patient's long-term mortality risk can be accurately assessed and subgroups of higher-risk patients can be identified for enhanced follow-up care. More research appears warranted to refine long-term CABG clinical risk models.

Does off-pump coronary artery bypass confer any advantage in patients with end-stage renal failure? A systematic review and meta-analysis

OBJECTIVES

Patients with end-stage renal disease (ESRD) are often excluded from trials comparing off and on-pump coronary artery bypass grafting (CABG). Thus data in this cohort is limited to small retrospective studies. Hence we compared the adverse clinical events and outcome in patients with ESRD undergoing off (OPCABG) and on-pump surgery (ONCABG).

METHODS

Pubmed, Scopus and Web of Science were searched (inception - June 2013) to identify studies comparing clinical results of OPCABG and ONCABG in dialysis dependent patients. A random effect inverse variance weighted meta-analysis was conducted. Results are presented as risk ratios (RR) with 95% confidence intervals; p<0.05 is significant.

RESULT

Ten retrospective studies (2762 OPCABG and 11310 ONCABG) fulfilled criteria and were pooled. Patients undergoing off-pump surgery were less than 100 in most of the articles. Early mortality [OPCABG (8.4%); ONCABG (10.4%)] was comparable [RR 0.80(0.51-1.17); p=0.35; I(2)=30%]. Re-exploration for bleeding [RR 0.81(0.47-1.39); p=0.44] and blood transfusion [RR 0.79(0.57-1.08); p=0.14] were also comparable. While patients undergoing off-pump surgery were extubated earlier (p<0.01), other post-operative events like stroke (p=0.34) and atrial fibrillation (p=0.10) were similar. Mid-term survival (three to five years) was also comparable.

CONCLUSION

Patients with end-stage renal disease undergoing coronary artery bypass grafting demonstrate comparable results irrespective of method. While available data is limited to retrospective studies, we failed to demonstrate any significant advantage for performing OPCABG in this group of patients.