The effect of completeness of revascularization during CABG with single versus multiple arterial grafts

Use of Indocyanine Green (ICG) to Assess Myocardial Perfusion and Territorial Distribution of Vein Grafts Implanted on Coronary Arteries in an Ex-vivo Porcine Model. A Potential Adjunct to Assist Revascularization Strategies and Training in Coronary Artery Bypass Grafting

Background

The fluorescent dye indocyanine green (ICG) has been used to identify anatomical structures intraoperatively in coronary artery bypass grafting (CABG). This study aimed to evaluate the feasibility of using ICG to assess graft patency and territorial distribution of myocardial reperfusion during CABG.

Methods

Porcine arrested hearts (n = 18) were used to evaluate territorial distribution of native coronary arteries and of a coronary bypass constructed with porcine saphenous vein graft (SVG) using ICG. Coronary ostia were dissected and selectively cannulated for ICG injection. Sequential fluorescence was assessed in the epicardial coronary arteries, myocardium and coronary veins using an infrared-sensitive charge-coupled device (CCD) camera system. In a separate set of experiments, SVG was used for anastomosis in end-to-side fashion to a terminal obtuse marginal (OM) branch. This approach was used to avoid bias in the assessment of territorial distribution. The anastomosis was injected with ICG; graft patency and territorial distribution was assessed using an infrared-sensitive CCD camera system from 30 cm above the field, as previously described. Native circulation and SVG grafts were assessed using real-time video recording and fluorescence intensity mapping that was averaged into a graded scoring system. The heart was divided into functional regions: anterior wall, lateral wall, inferior wall and right ventricle. All experiments were performed in triplicates.

Results

After ICG injection into the individual coronary ostia, perfusion of the native coronary artery was visible. Portions of the vessels embedded into the epicardial fat could be easily visualized on the surface of the heart and the dissection facilitated via fluorescence guidance. The territorial distribution reflected the expected regional perfusion. The SVG graft was anastomosed to an OM branch. ICG visualization allowed for assessment of graft patency excluding potential technical anastomosis problems or graft twisting or dissection. The myocardial perfusion observed in real-time confirmed regional distribution to the entire lateral wall and minimally to the inferior wall. These findings were confirmed in all the specimens used in the study.

Conclusions

Besides assisting the identification of intramyocardial vessels, ICG can provide information on the native coronary circulation status and the territorial distribution of the perfusion before and after grafting. It enables visualization of collaterals and the territory of distribution subtended by a graft offering real-time assessment and guidance on the grafting strategy.

Impact of Incomplete Revascularization on Long-term Survival Based on Revascularization Strategy

BACKGROUND

This study investigated the impact of complete revascularization (CR) and incomplete revascularization (IR) on long-term survival in patients undergoing isolated coronary artery bypass grafting (CABG) using multiple arterial graft (MAGs) or a single artery with saphenous vein grafts (SAGs).

METHODS

Between January 2006 and December 2020, 12,625 patients underwent CABG and were divided into 4 groups: MAG CR (n = 1066), MAG IR (n = 286), SAG CR (n = 8360), and SAG IR (n = 2913). Inverse probability of treatment weighting based on the generalized propensity score was used to minimize imbalance between the groups.

RESULTS

In the weighted cohort, median follow-up time was 8.35 years (interquartile range, 5.01-11.6 years). MAG CR was associated with similar long-term survival compared with MAG IR (hazard ratio [HR], 0.79; 95% CI, 0.60-1.03; P = .084). SAG CR was associated with improved long-term survival compared with SAG IR (HR, 0.67; 95% CI, 0.52-0.84; P = .01). MAG CR was associated with better long-term survival compared with SAG CR (HR, 0.45; 95% CI, 0.35-0.57; P < .001). Moreover, MAG IR was protective compared with SAG IR (HR, 0.62; 95% CI, 0.45-0.85; P = .033). Additional analysis was performed comparing perfect CR vs imperfect CR vs IR in MAG and SAG patients, separately. In the weighted sample of MAG, there were no differences in the long-term survival between perfect CR, imperfect CR, and IR. However, in the weighted sample of the SAG cohort, SAG perfect CR was associated with improved survival compared with SAG imperfect CR (HR, 0.81; 95% CI, 0.0.72-0.92; P = .001). Whereas, SAG perfect and imperfect CR were both associated with improved survival compared with SAG IR (HR, 0.51; 95% CI, 0.0.35-0.87; P = .006 and HR, 0.72; 95% CI, 0.64-0.82; P < .001), respectively.

CONCLUSIONS

MAG CR is associated with better survival compared with SAG CR. If IR is inevitable, patients with MAG IR had better long-term survival compared with patients receiving SAG IR. Moreover, similar long-term survival is observed whether perfect CR, imperfect CR, or IR is achieved in the MAG population but not in SAG patients.

A Comparative Analysis of Single Versus Multiple Arterial Grafts in Coronary Arterial Bypass Grafting: Initial Experience in Iraq

INTRODUCTION

The global recognition of multiple arterial grafting (MAG) and total arterial grafting (TAG) in coronary artery bypass grafting (CABG) is increasing. However, many centers have not yet adopted these procedures. Our study aims to examine the intraoperative, early postoperative, and two-year follow-up outcomes associated with MAG and TAG in candidates for CABG. The goal is to provide valuable insights into the role of these procedures.

METHODS

A prospective comparative study was conducted at Sulaimani Cardiac Hospital to analyze a cohort of 300 patients who underwent CABG surgery between January 2021 and April 2022. Convenience sampling was used to select participants. Prior to surgery, patients underwent comprehensive pre-operative evaluations, with certain CABG types being excluded. The patients were then categorized into three groups based on their surgical approach: single arterial conduit (SA), two arterial conduits (MA), and total arterial revascularization (TA). The standard bypass procedure was performed for all patients, and they were monitored for 30 days, six months, and two years after the surgery. A range of variables, including bypass and cross-clamp times, as well as postoperative complications such as bleeding and stroke, were recorded and analyzed. Statistical Product and Service Solutions (SPSS, version 25; IBM Corp., Armonk, NY) was used for this analysis, with a predetermined significance threshold of p ≤ 0.05.

RESULTS

The study included 300 participants who underwent CABG. The participants had an average age of 61.19 ± 4.67 years (95% CI: 36-81) and an average BMI of 27.40 ± 8.4 kg/m² (95% CI: 18-45). Diabetes was present in 40.3% of the patients, and the majority of the participants were male (77.7%). The number of vessels involved in the bypass varied, with two vessels in 21% of cases, three vessels in 65%, and four vessels in 14%. The left internal thoracic artery (LITA) was primarily used for arterial revascularization, and additional arterial conduits were used in 30.3% of cases. Statistical analysis showed significant differences in the number of grafts among patient groups (P = 0.042). However, there were no significant differences in bypass duration, cross-clamp duration, stroke incidence, or in-hospital mortality rates among the groups (P > 0.05). The rates of myocardial infarction (MI) approached significance (P = 0.05), and the mortality rates were comparable over a two-year period after CABG (4.7%) and at shorter intervals. These findings highlight the importance of age and the number of grafts in determining outcomes in CABG patients.

CONCLUSION

In a developing nation, the lack of a specialized center for MAG does not hinder the implementation of MAG or TAG. The overall occurrence of complications after CABG is similar across all groups, except for MI. Patients who undergo MAG have higher rates of overall survival compared to those who receive SA and TAG.

More Hospital Complications in Women after Cabg Even for Reduced Surgical Times: Call to Action for Equity in Quality Improvement

BACKGROUND

Analyses of extensive registries indicate adverse outcomes for women undergoing coronary artery bypass grafting (CABG) surgery, while randomized studies often lack representativeness.

OBJECTIVE

To compare adjusted hospital outcomes between men and women undergoing CABG.

METHODS

From July 2017 to June 2019, 3991 patients underwent primary isolated CABG, both electively and urgently, in 5 hospitals in the state of São Paulo, Brazil. To mitigate demographic differences between men and women, populations were adjusted using propensity score matching (PSM). The outcomes considered for analysis were those used by the STS Adult Database. The analyses were performed using R software, with a significance set at p<0.05.

RESULTS

After PSM (1:1), each group included 1089 patients. Regarding intraoperative variables, men exhibited longer cardiopulmonary bypass (CPB) time (p<0.001), surgical time (p<0.001), a higher number of distal anastomoses (p<0.001), and increased use of arterial grafts. Regarding outcomes, women had a higher incidence of deep sternal wound infection (p=0.006), prolonged Intensive Care Unit stay (p=0.002), increased need for an intra-aortic balloon pump (p=0.04), higher blood transfusion rates (p<0.001), higher 30-day hospital readmission rates after surgery (p=0.002) and higher mortality rate (p=0.03).

CONCLUSIONS

Although men had longer CPB times, a greater number of arterial grafts, and a greater number of distal anastomoses, immediate results after CABG were poorer in women.

Additional bypass graft or concomitant surgical ablation? Insights from the HEIST registry

BACKGROUND

Surgical ablation for atrial fibrillation at the time of isolated coronary artery bypass grafting is reluctantly attempted. Meanwhile, complete revascularization is not always possible in these patients. We attempted to counterbalance the long-term benefits of surgical ablation against the risks of incomplete revascularization.

METHODS

Atrial fibrillation patients undergoing isolated coronary artery bypass grafting for multivessel disease between 2012 to 2022 and included in the HEart surgery In atrial fibrillation and Supraventricular Tachycardia registry were divided into complete revascularization, complete revascularization with additional grafts, and incomplete revascularization cohorts; these were further split into surgical ablation and non-surgical ablation subgroups.

RESULTS

A total of 8,405 patients (78% men; age 69.3 ± 7.9) were included; of those, 5,918 (70.4%) had complete revascularization, and 556 (6.6%) had surgical ablation performed. Number of anastomoses was 2.7 ± 1.2. The median follow-up was 5.1 [interquartile range 2.1-8.8] years. In patients in whom complete revascularization was achieved, surgical ablation was associated with long-term survival benefit: hazard ratio 0.69; 95% confidence intervals (0.50-0.94); P = .020 compared with grafting additional lesions. Similarly, in patients in whom complete revascularization was not achieved, surgical ablation was associated with a long-term survival benefit of 0.68 (0.49-0.94); P = .019. When comparing surgical ablation on top of incomplete revascularization against complete revascularization without additional grafts or surgical ablation, there was no difference between the 2: 0.84 (0.61-1.17); P = .307, which was also consistent in the propensity score-matched analysis: 0.75 (0.39-1.43); P = .379.

CONCLUSION

To achieve complete revascularization is of utmost importance. However, when facing incomplete revascularization at the time of coronary artery bypass grafting in a patient with underlying atrial fibrillation, concomitant surgical ablation on top of incomplete revascularization is associated with similar long-term survival as complete revascularization without surgical ablation.

Impact of Graft Strategies on the Outcome of Octogenarians Undergoing Coronary Artery Bypass Grafting

PURPOSE

To analyse the outcome of coronary artery bypass grafting (CABG) in octogenarians with coronary multivessel disease and the impact of different graft strategies and other factors.

METHODS

Out of 1654 patients with multivessel disease who underwent CABG at our institution between January 2014 and March 2020, we investigated 225 consecutive patients with a median age of 82.1 years for survival prediction and need for coronary reintervention; a detailed outcome analysis was performed.

RESULTS

At mean follow-up of 3.3 years, the overall survival was 76.4%. An indication for emergency operation (p = 0.002), age (p <0.001), chronic pulmonary disease (p = 0.024), and reduced renal or ventricular function (p <0.001) had the highest impact on limited survival. The combination outcome of survival and coronary reintervention was 1.7-fold improved (p = 0.024) after use of the bilateral internal thoracic artery (BITA) (66.2%). Off-pump CABG (12%) revealed no impact on survival. Smokers showed a poorer outcome (p = 0.004). The logistic European System for Cardiac Operative Risk Evaluation was highly effective for evaluating long-term outcomes (p <0.001).

CONCLUSIONS

BITA grafting normalizes survival and reveals a better outcome in octogenarians with multivessel disease. However, patients at risk of poorer survival were operated under emergency conditions and those with pulmonary disease and reduced ventricular or renal function.

Clinical Insights to Complete and Incomplete Surgical Revascularization in Atrial Fibrillation and Multivessel Coronary Disease

Objectives

Although endorsed by international guidelines, complete revascularization (CR) with Coronary Artery Bypass Grafting (CABG) remains underused. In higher-risk patients such as those with pre-operative atrial fibrillation (AF), the effects of CR are not well studied.

Methods

We analyzed patients' data from the HEIST (HEart surgery In AF and Supraventricular Tachycardia) registry. Between 2012 and 2020 we identified 4770 patients with pre-operative AF and multivessel coronary artery disease who underwent isolated CABG. We divided the cohort according to the completeness of the revascularization and used propensity score matching (PSM) to minimize differences between baseline characteristics. The primary endpoint was all-cause mortality.

Results

Median follow-up was 4.7 years [interquartile range (IQR) 2.3-6.9]. PSM resulted in 1,009 pairs of complete and incomplete revascularization. Number of distal anastomoses varied, accounting for 3.0 + -0.6 vs. 1.7 + -0.6, respectively. Although early (< 24 h) and 30-day post-operative mortalities were not statistically different between non-CR and CR patients [Odds Ratio (OR) and 95% Confidence Intervals (CIs): 1.34 (0.46-3.86); P = 0.593, Hazard Ratio (HR) and 95% CIs: 0.88 (0.59-1.32); P = 0.542, respectively] the long term mortality was nearly 20% lower in the CR cohort [HR (95% CIs) 0.83 (0.71-0.96); P = 0.011]. This benefit was sustained throughout subgroup analyses, yet most accentuated in low-risk patients (younger i.e., < 70 year old, with a EuroSCORE II < 2%, non-diabetic) and when off-pump CABG was performed.

Conclusion

Complete revascularization in patients with pre-operative AF is safe and associated with improved survival. Particular survival benefit with CR was observed in low-risk patients undergoing off-pump CABG.

Complete surgical revascularization: Different definitions, same impact?

BACKGROUND

There are several different definitions of complete revascularization on coronary surgery across the literature. Despite the importance of this definition, there is no agreement on which one has the most impact. The aim of this study was to evaluate which definition of complete surgical revascularization correlates with early and late outcomes.

METHODS

All consecutive patients submitted to isolated CABG from 2012 to 2016 with previous myocardial scintigraphy were evaluated.

EXCLUSION CRITERIA

emergent procedures and previous cardiac surgery procedures. The population of 162 patients, follow-up complete in 100% patients; median 5.5; IQR: 4.4-6.9 years. Each and all of the 162 patients were classified as complying or not with the four different definitions: numerical, functional, anatomical conditional, and anatomical unconditional. Perioperative outcome: MACCE; long-term outcomes: survival and repeat revascularization. Univariable and multivariable analyses were developed to detect predictors of outcomes.

RESULTS

Complete functional revascularization was a predictor of increased survival (HR: 0.47; CI 95: 0.226-0.969; p = .041). No other definitions showed effect on follow-up mortality. Age and cardiac dysfunction increased long-term mortality. The definition of complete revascularization did not have an impact on MACCE or the need for revascularization CONCLUSIONS: A uniformly accepted definition of complete coronary revascularization is lacking. This study raises awareness about the importance of viability guidance for CABG.

Incidence and Prognostic Impact of Incomplete Revascularization Documented by Coronary Angiography 1 Year After Coronary Artery Bypass Grafting

Complete revascularization (CR) at the time of coronary artery bypass graft (CABG) surgery improves long-term cardiac outcomes. No studies have previously reported angiographically confirmed CR rates post-CABG. This study's aim was to assess the impact upon long-term outcomes of CR versus incomplete revascularization (IR), confirmed by coronary angiography 1 year after CABG. Randomized On/Off Bypass Study patients who returned for protocol-specified 1-year post-CABG coronary angiograms were included. Patients with a widely patent graft supplying the major diseased artery within each diseased coronary territory were considered to have CR. Outcomes were all-cause mortality and major adverse cardiovascular events (MACE; all-cause mortality, nonfatal myocardial infarction, repeat revascularization) over the 4 years after angiography. Of the 1,276 patients, 756 (59%) had CR and 520 (41%) had IR. MACE was 13% CR versus 26% IR, p <0.001. This difference was driven by fewer repeat revascularizations (5% CR vs 18% IR; p <0.001). There were no differences in mortality (7.1% CR vs 8.1% IR, p = 0.13) or myocardial infarction (4% in both). Adjusted multivariable models confirmed CR was associated with reduced MACE (odds ratio 0.44, 95% confidence interval 0.33 to 0.58, p <0.01), but had no impact on mortality. In conclusion, CR confirmed by post-CABG angiography was associated with improved MACE but not mortality. Repeat revascularization of patients with IR, driven by knowledge of the research angiography results, may have ameliorated potential mortality differences.

Residual Right Coronary Artery Stenosis after Left Main Coronary Artery Intervention Increased the 30-Day Cardiovascular Death and 3-Year Right Coronary Artery Revascularization Rate

Background

The outcomes of patients with concomitant left main coronary artery (LMCA) and right coronary artery (RCA) diseases are reportedly worse than those with only LMCA disease. To date, only few studies have investigated the clinical impact of percutaneous coronary intervention (PCI) on RCA stenosis during the same hospitalization, in which LMCA disease was treated. This study was aimed at comparing the outcomes between patients with and without right coronary artery intervention during the same hospital course for LMCA intervention.

Methods and Results

From a total of 776 patients who were undergoing PCI to treat LMCA disease, 235 patients with concomitant RCA significant stenosis (more than 70% stenosis) were enrolled. The patients were divided into two groups: 174 patients received concomitant PCI for RCA stenosis during the same hospitalization, in which LMCA disease was treated, and 61 patients did not receive PCI for RCA stenosis. Patients without intervention to the right coronary artery had higher 30-day cardiovascular mortality rates and 3-year RCA revascularization rates compared to those with right coronary artery intervention. Patients without RCA intervention at the same hospitalization did not increase the 30-day total death, 3-year myocardial infarction rate, 3-year cardiovascular death, and 3-year total death.

Conclusions

In patients with LM disease and concomitant above or equal to 70% RCA stenosis, PCI for RCA lesion during the same hospitalization is recommended to reduce the 30-day cardiovascular death and 3-year RCA revascularization rate.

On-Pump vs Off-Pump coronary artery bypass surgery in atrial fibrillation. Analysis from the polish national registry of cardiac surgery procedures (KROK)

Background

No single randomized study has ever before addressed the safety of On-Pump coronary artery bypass grafting (CABG) vs Off-Pump CABG in the setting of atrial fibrillation (AF) and data from small observational samples remain inconclusive.

Methods and findings

Procedural data from KROK (Polish National Registry of Cardiac Surgery Procedures) were retrospectively collected. Of initial 188,972 patients undergoing CABG, 7,913 presented with baseline AF (76.0% men, mean age 69.1±8.2) and underwent CABG without concomitant valve surgery between 2006–2019 in 37 reference centers across Poland. Mean follow-up was 4.7±3.5 years (median 4.3 IQR 1.7–7.4). Cox proportional hazards models were used for computations. Of included patients, 3,681 underwent On-Pump- (46.52%) as compared to 4,232 (53.48%) who underwent Off-Pump CABG. Patients in the latter group less frequently were candidates for complete revascularization (P<0.001). In an unadjusted comparison, On-Pump surgery was associated with significantly worse survival at 30 days: HR: 1.28; 95%CIs: (1.07–1.53); P = 0.007. Along the 13-year study period, the trend shifted in favor of On-Pump CABG: HR: 0.92; 95%CIs: (0.83–0.99); P = 0.005. After rigorous propensity matching, 636 pairs were identified. The direction and magnitude of treatment effects was sustained with HRs of 3.58; (95%CIs: 1.34–9.61); p = 0.001 and 0.74; [95%CIs: 0.56–0.98]; p = 0.036) for 30-day and late mortality respectively.

Conclusions

Off-Pump CABG offered 30-day survival benefit to patients undergoing CABG surgery and presenting with underlying AF. On-Pump CABG was associated with significantly improved survival at long term.

Impacts of incomplete revascularization following off-pump coronary artery bypass grafting on clinical outcomes of patients with triple-vessel lesions: insights from a single-center study of propensity-matched data

Background

Although complete revascularization (CR) has been a goal of surgical revascularization, comorbidities and anatomical variables often conspire against a successful surgical CR. Currently, incomplete revascularization (IR) has been also considered as an acceptable strategy of surgical revascularization in some categories of patients. In the past decade, off-pump coronary artery bypass grafting (CABG) became one of the mainstream procedures of CABG due to its low incidence of perioperative complications. However, the magnitude of the impacts of off-pump IR on clinical outcomes of patients with triple-vessel disease remained unclear.

Methods

Eligible patients who received isolated off-pump CABG with left internal mammary artery (LIMA) grafting to the left anterior descending coronary artery (LAD) in our institute from January 2011 to December 2013 were entered into an IR group or a CR group. The incidence of off-pump IR was investigated. In-hospital and follow-up outcomes were also evaluated by adjusting baseline characteristics using propensity score matching (1:1).

Results

A total of 1,349 patients (268 in the IR group and 1,081 in the CR group) were analyzed. The off-pump IR rate was 19.9%. Using matching propensity scores, 234 pairs were successfully established in a 1:1 manner. The two matched groups had similar surgical mortality and major postoperative morbidity. Multivariate Cox regression analysis showed that IR was not an independent predictor of cardiac death at follow-up (HR =1.215; 95% CI, 0.883-2.164; P=0.371). The two matched groups received a similar cumulative survival freedom from repeat revascularization in Kaplan-Meier curves (χ²=2.120, log-rank P=0.145).

Conclusions

CR can be achieved in the majority of off-pump CABG cases. Compared with off-pump CR, off-pump IR with the LIMA grafting to the LAD was associated with acceptable clinical outcomes.