Cardiac Surgery in Patients With Previous Hepatic or Renal Transplantation: A Pair-Matched Study

Cardiovascular outcomes in solid organ transplant recipients undergoing cardiac surgery: A matched pair analysis

INTRODUCTION

This study aimed to compare postoperative outcomes after cardiac surgery in solid-organ transplant recipients and nontransplant patients.

METHODS

We performed a retrospective analysis of 78 consecutive transplant recipients who underwent cardiac surgery at Asan Medical Center between 2000 and 2022 and were matched with 312 nontransplant patients who underwent cardiac surgery at a 1:4 ratio. The outcomes included 30-day mortality, all-cause death, cardiac death, readmission, and cardiac readmission.

RESULTS

There was no significant difference in baseline characteristics between the two groups. The most common type of cardiac surgery performed in solid organ transplant recipients was isolated valve surgery, followed by isolated CABG. The 30-day mortality was not significantly different between transplant recipients and nontransplant patients (3.9% vs. 3.5%; P > .99). Solid organ transplant recipients showed a higher all-cause mortality compared to nontransplant patients (29.1% vs. 14.3% at 5 years; P = .001); however, there was no significant difference in cardiac death between the two groups (2.6% vs. 3.2% at 5 years; P = .80). In addition, the readmission and cardiac readmission rates showed comparable findings to that of mortality.

CONCLUSION

Cardiac surgery can be performed safely in solid organ transplant recipients, with postoperative cardiovascular outcomes comparable to those observed in nontransplant patients.

Trends and Outcomes of Left Atrial Appendage Occlusion in Renal and Liver Transplant Recipients: Insights From the United States National Inpatient and Readmission Database

Left atrial appendage occlusion using the Watchman device has emerged as an alternative treatment strategy for preventing strokes in patients with atrial fibrillation. However, there is no data on its safety and clinical outcomes in prior renal or liver transplant recipients. We included a total of 61,995 patients from the National Inpatient Sample (NIS, in-hospital outcomes) and 55,048 patients from the National Readmission Database (NRD, 30-day outcomes) who underwent percutaneous left atrial appendage occlusion (LAAO). From this group, 0.65% (n=405) and 0.62% (n=339) were renal and liver transplant recipients in NIS and NRD respectively. Transplant recipients were younger compared with non-transplant recipients (mean age 69 vs 77 years, P=<0.01). There was little difference in terms of in-hospital mortality (0% vs 0.2%, P=0.43), major complications (6.2% vs 5.6%, P=0.61), cardiovascular complications (2.5% vs 2.8%, P=0.73), neurological complications (1.2% vs 0.7%, P=0.21) or bleeding complications (1.2% vs 0.7%, P=0.99) between transplant vs. non-transplant patients. Based on the NRD database, 30-day readmission rate was not meaningfully different for transplant recipients undergoing LAAO (9.44%) when compared to non-transplant patients (8.12%, [log-rank, P=0.56]). There was no difference between 30-day major or cardiovascular complications, however vascular complication rates were significantly higher for transplant recipients (OR 2.56, 95% CI [(1.66-3.47]). Our study findings suggest that LAAO may be safe for patients with a prior renal or liver transplant in terms of major complications, cardiovascular complications, and all-cause readmission rates. However vascular complications may be higher in transplant recipients. Further large-scale studies are needed to confirm these findings.

Management of cardiac diseases in liver transplant recipients: Comprehensive review and multidisciplinary practice-based recommendations

Cardiac diseases are one of the most common causes of morbidity and mortality following liver transplantation (LT). Prior studies have shown that cardiac diseases affect close to one-third of liver transplant recipients (LTRs) long term and that their incidence has been on the rise. This rise is expected to continue as more patients with advanced age and/or non-alcoholic steatohepatitis undergo LT. In view of the increasing disease burden, a multidisciplinary initiative was developed to critically review the existing literature (between January 1, 1990 and March 17, 2021) surrounding epidemiology, risk assessment, and risk mitigation of coronary heart disease, arrhythmia, heart failure, and valvular heart disease and formulate practice-based recommendations accordingly. In this review, the expert panel emphasizes the importance of optimizing management of metabolic syndrome and its components in LTRs and highlights the cardioprotective potential for the newer diabetes medications (e.g., sodium glucose transporter-2 inhibitors) in this high-risk population. Tailoring the multidisciplinary management of cardiac diseases in LTRs to the cardiometabolic risk profile of the individual patient is critical. The review also outlines numerous knowledge gaps to pave the road for future research in this sphere with the ultimate goal of improving clinical outcomes.

Inferior outcomes following cardiac surgery in patients with a functioning renal allograft

OBJECTIVES

Renal transplantation is an effective treatment for end-stage renal failure. The aim of this study was to evaluate outcomes for these patients undergoing cardiac surgery.

METHODS

A retrospective analysis identified patients with a functioning renal allograft at the time of surgery. A 2:1 propensity matching was performed. Patients were matched on: age, sex, left ventricle function, body mass index, preoperative creatinine, operation priority, operation category and logistic EuroSCORE.

RESULTS

Thirty-eight patients undergoing surgery with a functioning renal allograft were identified. The mean age was 62.4 years and 66% were male. A total of 44.7% underwent coronary artery bypass grafting and 26.3% underwent a single valve procedure. The mean logistic EuroSCORE was 10.65. The control population of 76 patients was well matched. Patients undergoing surgery following renal transplantation had a prolonged length of intensive care unit (3.19 vs 1.02 days, P < 0.001) and hospital stay (10.3 vs 7.17 days, P = 0.05). There was a higher in-hospital mortality (15.8% vs 1.3%, P = 0.0027). Longer-term survival on Kaplan-Meier analysis was also inferior (P < 0.001). One-year survival was 78.9% vs 96.1% and 5-year survival was 63.2% vs 90.8%. A further subpopulation of 11 patients with a failed renal allograft was identified and excluded from the main analysis; we report demographic and outcome data for them.

CONCLUSIONS

Patients with a functioning renal allograft are at higher risk of perioperative mortality and inferior long-term survival following cardiac surgery. Patients in this population should be appropriately informed at the time of consent and should be managed cautiously in the perioperative period with the aim of reducing morbidity and mortality.

Kidney-Pancreas Transplant Recipients Experience Higher Risk of Complications Compared to the General Population after Undergoing Coronary Artery Bypass Grafting

This retrospective analysis aims to identify differences in surgical outcomes between pancreas and/or kidney transplant recipients compared with the general population undergoing coronary artery bypass grafting (CABG). Using Nationwide Inpatient Sample (NIS) data from 2005 to 2014, patients who underwent CABG were stratified by either no history of transplant, or history of pancreas and/or kidney transplant. Multivariate analysis was used to calculate odds ratio (OR) to evaluate in-hospital mortality, morbidity, length of stay (LOS), and total hospital charge in all centers. The analysis was performed for both nonemergency and emergency CABG. Overall, 2,678 KTx (kidney transplant alone), 184 PTx (pancreas transplant alone), 254 KPTx (kidney-pancreas transplant recipients), and 1,796,186 Non-Tx (nontransplant) met inclusion criteria. KPTx experienced higher complication rates compared with Non-Tx (78.3 vs. 47.8%, p  < 0.01). Those with PTx incurred greater total hospital charge and LOS. On weighted multivariate analysis, KPTx was associated with an increased risk for developing any complication following CABG (OR 3.512, p  < 0.01) and emergency CABG (3.707, p  < 0.01). This risk was even higher at transplant centers (CABG OR 4.302, p  < 0.01; emergency CABG OR 10.072, p  < 0.001). KTx was associated with increased in-hospital mortality following emergency CABG, while PTx and KPTx had no mortality to analyze. KPTx experienced a significantly higher risk of complications compared with the general population after undergoing CABG, in both transplant and nontransplant centers. These outcomes should be considered when providing perioperative care.

Outcomes of transcatheter versus surgical aortic valve replacement among solid organ transplant recipients

BACKGROUND

There is a paucity of data regarding the outcomes of transcatheter aortic valve replacement (TAVR) versus surgical aortic valve replacement (SAVR) among solid-organ transplant recipients.

METHODS

Temporal trends in hospitalizations for aortic valve replacement among solid-organ transplant recipients were determined using the National Inpatient Sample database years 2012-2017. Propensity matching was conducted to compare admissions who underwent TAVR versus SAVR. The primary outcome was in-hospital mortality.

RESULTS

The analysis included 1,730 hospitalizations for isolated AVR; 920 (53.2%) underwent TAVR and 810 (46.7%) underwent SAVR. TAVR was increasingly utilized for solid-organ transplant recipients (P_trend = 0.01), while there was no change in the number of SAVR procedures (P_trend = 0.20). The predictors of undergoing TAVR for solid-organ transplant recipients included older age, diabetes, and prior coronary artery bypass surgery, while TAVR was less likely utilized in small-sized hospitals. TAVR was associated with lower in-hospital mortality after matching (0.9 vs. 4.7%, odds ratio [OR] 0.19; 95% confidence interval [CI] 0.11-0.35, p < .001) and after multivariable adjustment (OR 0.07; 95% CI 0.03-0.21, p < .001). TAVR was associated with lower rate of acute kidney injury, acute stroke, postoperative bleeding, blood transfusion, vascular complications, discharge to nursing facilities, and shorter median length of hospital stay. There was no difference between both groups in the use of mechanical circulatory support, hemodialysis, arrhythmias, or pacemaker insertion.

CONCLUSION

This contemporary observational nationwide analysis showed that TAVR is increasingly performed among solid-organ transplant recipients. Compared with SAVR, TAVR was associated with lower in-hospital mortality, complications, and shorter length of stay.

Postoperative outcomes of kidney transplant recipients undergoing non-transplant-related elective surgery: a systematic review and meta-analysis

Background

Reliable estimates of the absolute and relative risks of postoperative complications in kidney transplant recipients undergoing elective surgery are needed to inform clinical practice. This systematic review and meta-analysis aimed to estimate the odds of both fatal and non-fatal postoperative outcomes in kidney transplant recipients following elective surgery compared to non-transplanted patients.

Methods

Systematic searches were performed through Embase and MEDLINE databases to identify relevant studies from inception to January 2020. Risk of bias was assessed by the Newcastle Ottawa Scale and quality of evidence was summarised in accordance with GRADE methodology (grading of recommendations, assessment, development and evaluation). Random effects meta-analysis was performed to derive summary risk estimates of outcomes. Meta-regression and sensitivity analyses were performed to explore heterogeneity.

Results

Fourteen studies involving 14,427 kidney transplant patients were eligible for inclusion. Kidney transplant recipients had increased odds of postoperative mortality; cardiac surgery (OR 2.2, 95%CI 1.9–2.5), general surgery (OR 2.2, 95% CI 1.3–4.0) compared to non-transplanted patients. The magnitude of the mortality odds was increased in the presence of diabetes mellitus. Acute kidney injury was the most frequently reported non-fatal complication whereby kidney transplant recipients had increased odds compared to their non-transplanted counterparts. The odds for acute kidney injury was highest following orthopaedic surgery (OR 15.3, 95% CI 3.9–59.4). However, there was no difference in the odds of stroke and pneumonia.

Conclusion

Kidney transplant recipients are at increased odds for postoperative mortality and acute kidney injury following elective surgery. This review also highlights the urgent need for further studies to better inform perioperative risk assessment to assist in planning perioperative care.

Cardiac Surgery and Postoperative Renal Allograft Failure

BACKGROUND

Although cardiac surgery among renal allograft recipients is relatively safe, less is known about the impact of cardiac surgery on the functioning renal allograft. This study assessed postoperative renal failure among renal transplant recipients undergoing cardiac surgery.

METHODS

The study population was identified by matching medical record numbers from the United Network for Organ Sharing Kidney Transplant Database to a cardiovascular surgery database and The Society of Thoracic Surgeons Adult Cardiac Surgery Database for the authors' institution from January 1992 through August 2018.

RESULTS

One hundred seventy-nine renal transplant recipients with a functioning allograft underwent cardiac surgery a mean of 6.4 ± 5.6 years after renal transplantation. Thirty (17.6%) of the 170 patients either died or had allograft failure during the first postoperative year. Receiver-operating characteristics curve analysis using Cox regression demonstrated an optimal cutoff point for preoperative serum creatinine predicting postoperative allograft loss is 1.9 mg/dL (hazard ratio 3; 95% confidence interval, 1.5 to 6.9) with a model C statistic of 0.642.

CONCLUSIONS

The current study affirms findings in the literature that cardiac surgery in renal transplant recipients carries acceptable perioperative morbidity and mortality. Renal transplant recipients who underwent cardiac surgery had a constant hazard of renal allograft loss similar to that of the general transplant population. A preoperative serum creatinine value greater than 1.9 mg/dL increases the risk for long-term renal allograft loss after cardiac surgery.

Cardiac valve operations after solid organ transplantation: A single-center experience

OBJECTIVE

Cardiac valve operations in patients who have undergone solid organ transplantation (ie, kidney, liver, pancreas, heart, and lung) pose unique challenges due to patient comorbidities and to the need for immunosuppressive therapy. The aim of this retrospective study was to present our experience with patients with solid-organ transplant who had cardiac valve operation at the time or after transplantation.

METHODS

Records of patients who had undergone cardiac valve operations after solid organ transplantation between January 1998 and January 2019 were retrospectively reviewed. Follow-up amounted to a median of 51 months (interquartile range, 5-88 months).

RESULTS

Among the 14,465 patients who underwent treatment for a cardiac valvular pathology during the study period, 127 patients (0.9%) had undergone a solid organ transplantation (kidney: n = 9 [76%]; liver: n = 12 [9%]; pancreas: n = 4 [3%]; heart: n = 16 [13%]; lung: n = 9 [7%]). Postoperatively, 14 patients (11%) underwent rethoracotomy for bleeding and 24 patients (19%) required new dialysis treatment. Twenty-five patients (20%) died in-hospital. Postoperative course was worse in patients operated for endocarditis or undergoing concomitant transplantation and valve surgery. Overall survival was 59%, 47%, and 40%, but survival conditioned to hospital discharge was 73%, 58%, and 50% at 5-, 10-, and 15-year follow-up, respectively. Freedom from major valve-related events amounted to 77%, 56%, and 46%, respectively.

CONCLUSIONS

Although the high prevalence of postoperative complications, especially in patients with endocarditis or concomitant transplantation and valve surgery, survival conditioned to hospital discharge was satisfactory in patients undergoing valve surgery after solid organ transplantation.

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.

Long-Term Clinical Outcomes of Cardiac Surgery for Kidney Transplant Patients

PURPOSE

Immunosuppressant and steroid are inevitable for graft survival after renal transplantation, and their usage is known to be a risk factor for mortality and morbidity after cardiac surgery. We evaluated the long-term clinical outcomes in patients who underwent cardiac surgery after renal transplantation.

METHODS

We retrospectively reviewed 23 patients who underwent cardiac surgery after renal transplantation with maintained grafts at the time of the cardiac surgery in our institution between June 2000 and June 2018 (19 males, 4 females; mean age, 55 (38-81) years).

RESULTS

The interval from renal transplantation to cardiac surgery was 80.0 ± 84.6 (0.25-298) months. The mean follow-up period after cardiac surgery was 78.3 (range: 1-216) months. Cumulative survival rates at 1, 5, 7, and 10 years were 95.7%, 95.7%, 87.7%, and 68.2%, respectively. Renal graft survival rates at 1 and 5 years were 86.1% and 79.9%, respectively.

CONCLUSIONS

This retrospective review suggests that cardiac surgery in kidney transplant patients can result in good survival rates. Thanks to dedicated postoperative and long-term management, approximately 80% of the renal grafts still maintained their function 5 years after cardiac surgery.