Reoperation for Coronary Artery Bypass Grafting Surgery: Outcomes and Considerations for Expanding Interventional Procedures

Redo coronary artery bypass grafting: when and how

PURPOSE OF REVIEW

Redo coronary artery bypass grafting (CABG) remains technically challenging with significant procedural risk but may be the best option for patients in whom repeat revascularization is indicated. This review summarizes the latest data regarding risk of redo CABG, who should receive this surgery, and how to achieve best outcomes.

RECENT FINDINGS

Over the past two decades, the risk of performing redo CABG has declined and is approaching that of primary CABG in the hands of experienced surgeons. Nonetheless, patients for whom redo CABG is indicated tend to be older and have more complex medical comorbidities. Preoperative imaging is paramount in guiding sternal re-entry and mediastinal dissection, and in how to best employ rescue strategies when needed.

SUMMARY

Patients with complex, progressive coronary disease with unprotected left anterior descending (LAD) coronary artery disease and prior coronary bypass may benefit from the durable, complete revascularization that redo CABG can offer with internal thoracic artery bypass to the LAD and, when possible, arterial inflow to other important coronary targets. Preoperative imaging, careful planning, meticulous surgical technique, myocardial protection, and an experienced surgical team are critical for optimal outcomes.

Fibrin Hydrogel Layer-Anchored Pericardial Matrix Prevents Epicardial Adhesion in the Severe Heart Adhesion-Induced Miniature Pig Model

Postoperative adhesion is a very common and serious complication that occurs frequently in cardiac surgery. The purpose of this study was to evaluate the efficacy of a fibrin hydrogel layer-anchored decellularized pericardial matrix in preventing pericardial adhesions in a miniature pig model with a myocardial injury. Fibrin hydrogel layer-anchored decellularized pericardial matrix was prepared by spraying a mixture of fibrinogen and thrombin on a fibrinogen-doped decellularized pericardium. Cardiac injury was generated by abrading and desiccating the epicardial surface of a miniature pig to induce severe postoperative adhesions. The adhesion between the epicardial surface and fibrin hydrogel layer-anchored decellularized pericardial matrix in three different regions (left outer, front, and right outer) was evaluated macroscopically one month after surgery. The fibrin hydrogel layer-anchored decellularized pericardial matrix showed significantly less adhesion than an autologous pericardium (0.2 ± 0.7 in DPM-FHG0.5 and 0.4 ± 0.8 in DPM-FHG1, p < 0.01) and expanded polytetrafluoroethylene (ePTFE) (1.6 ± 0.5, p < 0.05). The fibrin hydrogel concentration had no effect on preventing postoperative adhesion. A thinner fibrin hydrogel layer was observed on the decellularized pericardial matrix one month after surgery; however, the inside of the matrix was filled with fibrin hydrogel. Fibrin hydrogel layer-anchored decellularized pericardial matrix prevented postoperative epicardial adhesions in a miniature pig model. Our findings suggest that pericardial closure using a fibrin hydrogel layer-anchored decellularized pericardial matrix is a promising method for preventing adverse outcomes in reoperative surgeries.

Osteopontin Activation and Microcalcification in Venous Grafts Can Be Modulated by Dexamethasone

BACKGROUND

Osteopontin has been implicated in vascular calcification formation and vein graft intimal hyperplasia, and its expression can be triggered by pro-inflammatory activation of cells. The role of osteopontin and the temporal formation of microcalcification in vein grafts is poorly understood with a lack of understanding of the interaction between haemodynamic changes and the activation of osteopontin.

METHODS

We used a porcine model of vein interposition grafts, and human long saphenous veins exposed to ex vivo perfusion, to study the activation of osteopontin using polymerase chain reaction, immunostaining, and 18F-sodium fluoride autoradiography.

RESULTS

The porcine model showed that osteopontin is active in grafts within 1 week following surgery and demonstrated the presence of microcalcification. A brief pretreatment of long saphenous veins with dexamethasone can suppress osteopontin activation. Prolonged culture of veins after exposure to acute arterial haemodynamics resulted in the formation of microcalcification but this was suppressed by pretreatment with dexamethasone. 18F-sodium fluoride uptake was significantly increased as early as 1 week in both models, and the pretreatment of long saphenous veins with dexamethasone was able to abolish its uptake.

CONCLUSIONS

Osteopontin is activated in vein grafts and is associated with microcalcification formation. A brief pretreatment of veins ex vivo with dexamethasone can suppress its activation and associated microcalcification.

[Repeated Coronary Artery Bypass Surgery 18 Years After the Primary Revascularization of Myocardium in a Patient With Acute Coronary Syndrome Without the Segment ST Elevation]

This article describes a clinical case of successful repeated coronary bypass grafting 18 years after the initial surgery in a patient with non-ST-elevation acute coronary syndrome.

Reoperative CABG in a patient with prior concomitant lung transplantation and two-vessel CABG

BACKGROUND

Lung transplants (LTx) are being offered to increasingly older patients, and as a result, more concomitant coronary artery disease is being encountered in LTx candidates. While concurrent coronary artery bypass grafting (CABG) and LTx have become more common, the long-term considerations of reoperative CABG in patients following CABG with concomitant LTx are not fully understood.

CASE PRESENTATION

A 75-year-old man with a history of bilateral LTx and concomitant CABG X 2 15 years prior presented to the emergency room with tachycardia and chest discomfort radiating to the left upper extremity. Emergent coronary angiography revealed severe three-vessel coronary artery disease with two occluded saphenous vein grafts, severe distal obtuse marginal (OM) and left circumflex disease, a collateralized chronic total occlusion of the mid LAD, and tortuosity of the proximal right innominate artery. The patient underwent a complex redo sternotomy and CABG X 2 due to dense adhesions in the mediastinum and pleura bilaterally. The postoperative course was complicated by left leg SVG harvest site cellulitis treated with IV antibiotics and hypervolemia treated with diuresis. The patient was discharged postoperatively on day 13.

DISCUSSION

To our knowledge, this is the first reported successful reoperative CABG in a patient with a history of concomitant LTx and CABG. This case demonstrates feasibility, though additional caution is required due to the technical complexity and risk of immunosuppression in such complex patients.

Recent Advances in Coronary Artery Bypass Grafting Techniques and Outcomes: A Narrative Review

Coronary artery bypass grafting (CABG) has witnessed remarkable progress in recent years, driven by innovative techniques and refined approaches that have transformed patient outcomes and treatment paradigms. This review article comprehensively explores the latest advances in CABG techniques and their consequential impacts on patient outcomes. The advent of minimally invasive CABG techniques has revolutionized traditional surgical approaches. Robotic-assisted surgery and small thoracotomy methods offer reduced invasiveness, yielding shorter recovery times and improved patient satisfaction. Integrating CABG with percutaneous coronary intervention (PCI), hybrid procedures have emerged as a versatile strategy, providing tailored treatment solutions for complex coronary anatomies. The paradigm shift to off-pump CABG, which preserves the beating heart during surgery, has shown promise in reducing perioperative complications and neurocognitive deficits. Advances in graft selection, particularly the utilization of arterial grafts such as the internal thoracic artery and radial artery, have significantly enhanced graft patency rates and long-term survival. Adjunctive technologies, such as intraoperative imaging and graft flow assessment, have bolstered the precision of CABG procedures. Pharmacological agents have demonstrated their potential to improve graft outcomes. Surgical decision-making is now optimized based on patient characteristics and disease severity owing to the development of patient selection and risk stratification tools. Long-term results have also significantly improved. Patients undergoing CABG have higher survival rates, less angina, and better quality of life. Developing more resilient grafts through tissue engineering, using bioresorbable materials in graft fabrication, and using gene therapy to improve graft patency and overall cardiac recovery are all exciting future research directions. This review's summary of current developments in CABG procedures highlights their profoundly positive effects on patient outcomes. These developments can change the face of cardiovascular care by giving clinicians more tools to treat coronary artery disease (CAD) and enhance patients' quality of life.

The Role of Preservation Solutions upon Saphenous Vein Endothelial Integrity and Function: Systematic Review and UK Practice Survey

The long saphenous vein is the most used conduit in cardiac surgery, but its long-term patency is limited by vein graft disease (VGD). Endothelial dysfunction is a key driver of VGD; its aetiology is multi-factorial. However emerging evidence identifies vein conduit harvest technique and preservation fluids as causal in their onset and propagation. This study aims to comprehensively review published data on the relationship between preservation solutions, endothelial cell integrity and function, and VGD in human saphenous veins harvested for CABG. The review was registered with PROSPERO (CRD42022358828). Electronic searches of Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE databases were undertaken from inception until August 2022. Papers were evaluated in line with registered inclusion and exclusion criteria. Searches identified 13 prospective, controlled studies for inclusion in the analysis. All studies used saline as a control solution. Intervention solutions included heparinised whole blood and saline, DuraGraft, TiProtec, EuroCollins, University of Wisconsin (UoW), buffered, cardioplegic and Pyruvate solutions. Most studies demonstrated that normal saline appears to have negative effects on venous endothelium and the most effective preservation solutions identified in this review were TiProtec and DuraGraft. The most used preservation solutions in the UK are heparinised saline or autologous whole blood. There is substantial heterogeneity both in practice and reporting of trials evaluating vein graft preservation solutions, and the quality of existing evidence is low. There is an unmet need for high quality trials evaluating the potential for these interventions to improve long-term patency in venous bypass grafts.

Trends of re-operative coronary artery bypass grafting: A two-decade experience

BACKGROUND

The prevalence of redo coronary artery bypass grafting has markedly changed over the last two decades. We aim to assess the trends of redo coronary artery bypass grafting and clinical outcomes of redo coronary artery bypass grafting over two different periods.

METHODS

This is a retrospective, metachronous, observational study of patients who underwent redo coronary artery bypass grafting between January 1998 through December 2004 and January 2005 through September 2021 who were categorized into group 1 and group 2, respectively. The trends in the prevalence of redo coronary artery bypass grafting, and 30-day outcomes were analyzed.

RESULTS

A total of 261 patients underwent a redo coronary artery bypass grafting. Group 1 and group 2 included 114 and 147 patients, respectively. 62.59% of group 2 patients underwent off-pump coronary artery bypass grafting compared to 6.14% in group 1 (p < 0.01). The patients undergoing redo coronary artery bypass grafting in group 2 were significantly older (60.65 ± 7.78 years vs. 50.99 ± 7.66 years, p < 0.001) and were more likely to be hypertensive (49.66% vs. 29.82%, p < 0.001). There was no significant difference in the proportion of diabetes (p = 0.82), smoking (p = 0.24), dyslipidemia (p = 0.64), and preoperative myocardial infarction (p = 0.14). The proportion of patients who presented post-PCI was significantly higher in group 2 (27.89% vs. 10.53%, p < 0.001). There was also a shift in the usage of grafts from the left internal thoracic artery to the saphenous vein graft (p < 0.001).

CONCLUSION

The annual rate of redo coronary artery bypass grafting was declining but has now reached a plateau. The current outcomes of patients undergoing redo coronary artery bypass grafting are comparable to that of the earlier times despite a higher co-morbidity burden in patients of recent times.

Resternotomy Coronary Artery Bypass 1999-2018: Insights From The Society of Thoracic Surgeons Adult Cardiac Surgery Database

BACKGROUND

We sought to quantify the risk trend of resternotomy coronary artery bypass grafting (CABG) over the past 2 decades.

METHODS

We compared the outcomes of 194 804 consecutive resternotomy CABG patients and 1 445 894 randomly selected first-time CABG patients (50% of total) reported to The Society of Thoracic Surgeons Adult Cardiac Surgery Database between 1999 and 2018. Primary outcomes were in-hospital mortality and overall morbidity. Using multiple logistic regression for each outcome for each year, we computed the annual trends of risk-adjusted odds ratios for the primary outcomes in the entire cohort and in 194 776 propensity-matched pairs.

RESULTS

The annual resternotomy CABG case volume from participating centers declined by 68%, from a median of 25 (range, 14-44) to a median of 8 (range, 4-15). Compared with first-time CABG, resternotomy CABG patients were consistently older, with higher proportions of comorbidities. After propensity matching, primary outcomes of resternotomy and first-time CABG were similar (mortality: 3.5% vs 2.3%, standardized difference [SDiff], 7.5%; morbidity: 40.7% vs 40.3%, SDiff, 0.9%). Mortality of resternotomy CABG performed after prior CABG was higher than that after prior non-CABG (4.3% vs 2.4%; SDiff, 10.8). Morbidity was similar between these subgroups (41.0% vs 39.1%; SDiff, 2.9). The adjusted odds ratio for mortality after resternotomy CABG declined from 1.93 (95% CI, 1.73-2.16) to 1.22 (95% CI, 0.92-1.62), and that of morbidity declined from 1.13 (95% CI, 1.08-1.18) to 0.91 (95% CI, 0.87-0.95), P < .001 for both.

CONCLUSIONS

The risk of resternotomy CABG has decreased substantially over time. Resternotomy CABG performed after a prior CABG is higher risk compared with that performed after a non-CABG operation.

Early cardiac contractility outcome of reoperative coronary artery bypass grafting using right gastroepiploic artery

BACKGROUND AND AIM OF THE STUDY

Reoperative coronary artery bypass grafting (redo CABG) still carries higher mortality and increased morbidity compared with primary CABG. In this study, we retrospectively reviewed our operative outcome of redo CABG to evaluate the impact of the left anterolateral thoracotomy approach using the right gastroepiploic artery (RGEA).

METHODS

Between 1994 and 2020, 11 patients (mean age 60.3 ± 13.1 years; nine men, two women) underwent isolated redo CABG using the RGEA via the left anterolateral thoracotomy.

RESULTS

The mean duration from the initial CABG was 128.3 ± 88.4 months. Redo CABG was performed because of graft occlusion in six patients (54.5%), graft stenosis in one patient (9.1%), and progressive disease of previously ungrafted vessels in four patients (36.4%). The total number of bypasses using RGEA (including Y-composite vein grafts) was 16 (four left anterior descending branches, two diagonal branches, five circumflex branches, five right coronary arteries). No residual graft injury, major comorbidity, or in-hospital death was observed. Changes in echocardiographic values before and after redo CABG were 210.9 ± 48.2 ml and 175.0 ± 41.4 ml in left ventricular end-diastolic volume, 130.2 ± 49.2 ml and 94.4 ± 33.0 ml in left ventricular end-systolic volume, and 45.6 ± 11.0% and 52.2 ± 10.7% in left ventricular ejection fraction, respectively. These parameters significantly improved after redo CABG.

CONCLUSIONS

Redo CABG with RGEA grafting via the left anterolateral thoracotomy approach is a safe and effective surgical procedure especially in improving cardiac contractility in patients who required revascularization.

Mid-Term Outcomes and Angiographic Patency of Redo Coronary Artery Bypass Grafting: A Comparison between Off-Pump and On-Pump Surgery

Background

We evaluated the mid-term outcomes and angiographic patency of redo coronary artery bypass grafting (CABG).

Methods

Of 2,851 patients who underwent isolated CABG at Seoul National University Hospital from 2000 to 2017, 88 underwent redo CABG. Patients’ mean age at redo CABG was 66.0±8.0 years. The mean interval between the first-time and redo CABG was 113.0±62.4 months. The mean follow-up duration was 86 months. Early and mid-term clinical outcomes were evaluated. Angiographic patency rates were evaluated early (1–2 days), 1 year, and 5 years after surgery. Comparative analyses between on-pump and off-pump CABG were also performed.

Results

The culprits for reoperation were previous grafts (65.6%), native coronary vessels (17.8%), and both (16.7%). Off-pump CABG was performed in 75 cases (85.2%), and the mean number of distal anastomoses was 1.8±0.8. The saphenous vein (39.7%) was used most frequently, followed by the right internal thoracic artery (28.4%), right gastroepiploic artery (21.3%), left internal thoracic artery (7.8%), and radial artery (2.8%). Operative mortality was 1.1%. The overall survival, cumulative incidence of cardiac death, and cumulative incidence of major adverse cardiac events were 71.3%,12.0%, and 23.3% at 5 years after surgery, respectively. The overall angiographic patency rates were 95.7%, 90.1%, and 92.2% on early, 1-year, and 5-year angiograms, respectively. The angiographic patency rates of saphenous vein grafts were 93.1%, 85.6%, and 91.3% on early, 1-year, and 5-year angiograms, respectively. No significant differences in clinical outcomes or angiographic patency rates were observed between the on-pump (n=13) versus off-pump (n=75) groups. Multivariable analysis revealed that age (hazard ratio [HR], 1.07; p=0.005) and chronic kidney disease (HR, 3.85; p=0.001) were risk factors for all-cause mortality.

Conclusion

Redo CABG could mostly be performed using the off-pump technique and did not show increased operative mortality and morbidities.

Advances in the Post-coronary Artery Bypass Graft Management of Occlusive Coronary Artery Disease

Revascularisation of chronic total occlusion (CTO) represents one of the most challenging aspects of percutaneous coronary intervention, but advances in equipment and an understanding of CTO revascularisation techniques have resulted in considerable improvements in success rates. In patients with prior coronary artery bypass grafting (CABG) surgery, additional challenges are encountered. This article specifically explores these challenges, as well as antegrade methods of CTO crossing. Techniques, equipment that can be used and reference texts are highlighted with the aim of providing potential CTO operators adequate information to tackle additional complexities likely to be encountered in this cohort of patients. This review forms part of a wider series where additional aspects of patients with prior CABG should be factored into decisions and methods of revascularisation.

Trends in Reoperative Coronary Artery Bypass Graft Surgery for Older Adults in the United States, 1998 to 2017

Background The likelihood of undergoing reoperative coronary artery bypass graft surgery (CABG) is important for older patients who are considering first-time CABG. Trends in the reoperative CABG for these patients are unknown. Methods and Results We used the Medicare fee-for-service inpatient claims data of adults undergoing isolated first-time CABG between 1998 and 2017. The primary outcome was time to first reoperative CABG within 5 years of discharge from the index surgery, treating death as a competing risk. We fitted a Cox regression to model the likelihood of reoperative CABG as a function of patient baseline characteristics. There were 1 666 875 unique patients undergoing first-time isolated CABG and surviving to hospital discharge. The median (interquartile range) age of patients did not change significantly over time (from 74 [69-78] in 1998 to 73 [69-78] in 2017); the proportion of women decreased from 34.8% to 26.1%. The 5-year rate of reoperative CABG declined from 0.77% (95% CI, 0.72%-0.82%) in 1998 to 0.23% (95% CI, 0.19%-0.28%) in 2013. The annual proportional decline in the 5-year rate of reoperative CABG overall was 6.6% (95% CI, 6.0%-7.1%) nationwide, which did not differ across subgroups, except the non-white non-black race group that had an annual decline of 8.5% (95% CI, 6.2%-10.7%). Conclusions Over a recent 20-year period, the Medicare fee-for-service patients experienced a significant decline in the rate of reoperative CABG. In this cohort of older adults, the rate of declining differed across demographic subgroups.

Outcomes of Reoperative Coronary Artery Bypass Graft Surgery in the United States

Background There is a paucity of data on the trends and outcomes of reoperative coronary artery bypass graft (CABG) surgery during the current decade in the United States. Methods and Results We queried the National Inpatient Sample database (2002-2016) for all hospitalizations with isolated CABG procedure. We reported the temporal trends and outcomes of reoperative CABG versus primary CABG procedures. The main outcome was in-hospital mortality. Among 3 212 768 hospitalizations with CABG, 46 820 (1.5%) had reoperative CABG. Over the 15-year study period, there were no changes in the proportion of reoperative CABG (1.8% in 2002 versus 2.2% in 2016, Ptren=0.08), and the related in-hospital mortality (3.7% in 2002 versus 2.7% in 2016, Ptrend=0.97). Reoperative CABG was performed in patients with increasingly higher risk profile. Compared with primary CABG, hospitalizations for reoperative CABG were associated with higher in-hospital mortality (3.2% versus 1.9%, P<0.001), cardiac arrest, cardiogenic shock, vascular complications, and respiratory complications. Among hospitalizations for reoperative CABG, the predictors of higher mortality included history of heart failure and chronic kidney disease. Conclusions In this 15-year nationwide analysis, reoperative CABG procedures were increasingly performed in patients with higher risk profile. In-hospital mortality rates were relatively low and did not change during the examined period. Compared with primary CABG, reoperative CABG is associated with higher in-hospital mortality.

[Long-term outcomes of coronary artery bypass surgery in young patients]

OBJECTIVE

To analyze long-term outcomes of CABG in young patients, incidence and structure of adverse cardiovascular events depending on patients' age.

MATERIAL AND METHODS

There were 175 young patients (up to 44 years old in accordance with WHO classification) who underwent CABG for the period from 2006 to 2016. The control group included 175 patients aged 45 years and older who were randomly selected among patients operated in the same period. Overall long-term follow-up period was 81.9±15.75 months (≈ 6.8 years). Data on long-term survival and adverse cardiovascular events were available in 86.3% of patients in general sample and 72.6% of young patients.

RESULTS

Young patients undergoing CABG were usually characterized by the absence of severe concomitant diseases, moderate coronary atherosclerosis by SYNTAX Score scale, high percentage of left ventricular aneurysm and previous PCI. Incidence and structure of in-hospital and long-term adverse cardiovascular events in young and older patients confirmed satisfactory results of CABG regardless age.

Redo coronary artery bypass grafting

Purpose

Redo coronary artery bypass grafting (CABG) can be one of the most technically challenging operations in cardiac surgery. The coronary disease is more advanced, and the coronary targets may be suboptimal. In addition, the patients are typically older and sicker compared to those undergoing primary CABG.

Methods

A literature review focused on the epidemiology, operative techniques, and outcomes associated with redo CABG.

Results

The frequency of redo CABG relative to total CABG procedures has been decreasing over time. From 2000 to 2009, redo CABG decreased from 6.0 to 3.4% of all CABG procedures reported to the STS Adult Cardiac Surgery Database (STS ACSD) and currently stands at 2%. Risks associated with reoperations include diabetes and renal dialysis. Perioperative mortality for redo CABG is reported to be as high as three times that of primary CABG, but this risk is reduced with experience. Careful preoperative planning including quality imaging and precise surgical technique coupled with meticulous myocardial protection contributes to good outcomes. Experience is important in optimizing outcomes.

Conclusions

Redo CABG is a complicated operation and surgical experience, and appropriate perioperative strategies are essential for achieving optimal outcomes.