Long Term Outcomes of The Off-Pump and On-Pump Coronary Artery Bypass Grafting In A High-Volume Center

Off-pump CABG surgery in left main coronary artery disease: a single-center prospective registry

Background and objective

The treatment of left main (LM) coronary artery disease (CAD) requires complex decision-making. Patients with left main multi-vessel coronary artery disease (LM CAD) have concerns regarding incomplete revascularization and reduced survival with off-pump (OPCAB) when compared with on-pump (ONCAB) coronary bypass surgery. To evaluate outcomes among high-risk LM CAD patients undergoing OPCAB, we performed a registry-based prospective study.

Methods

We performed 4868 coronary artery bypass graft (CABG) surgeries from Jan 2013 to Jun 2019 with 4662 (95.8%) OPCAB. In OPCAB cohort, we had 1323 patients (28.4%) with significant LM (> 50%) triple vessel CAD. Data regarding clinical features, extent of CAD, operative details, in-hospital outcomes, and 3-year follow-up were obtained. Descriptive statistics are reported.

Results

The study cohort (n = 1323) was aged 63 ± 9 years with men 88.4%. Tobacco use was in 328 (24.8%), diabetes 598 (45.2%), previous myocardial infarction 463 (35.0%), previous coronary intervention 40 (3.0%), and congestive heart failure in 54 (4.1%). All patients had LM (100.0%) with triple vessel disease in 99.4% (LAD, left anterior descending 100.0%; LCX, left circumflex 99.4%; RCA, right coronary artery 78.7%). Vessels bypassed/patient were 2.7 ± 0.4 with 3.2 ± 0.7 total grafts and 2.1 ± 0.8 venous grafts. In total, 1278 (96.5%) patients received left internal mammary artery (LIMA), 63(4.7%) bilateral internal mammary artery (BIMA), and 74 (5.6%) radial artery grafts. There was no patient with conversion from OPCAB to ONCAB. In-hospital major adverse cardiovascular events (MACE: all-cause deaths, myocardial infarction, and stroke) were in 21 (1.6%). At 3-year follow-up (n = 1041), MACE rates were in 84 (8.1%) and cardiovascular deaths in 28 (2.7%).

Conclusions

This study shows that off-pump CABG surgery is safe in patients with LM CAD. There is low in-hospital mortality and MACE and 3-year outcomes are similar to the published data of LM CAD patients who undergo on-pump CABG.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12055-023-01526-3.

Predicting Determinants for Conversion of Off-Pump Coronary Revascularization to On-Pump Surgery: A Retrospective Analysis

A global consensus has not yet been reached regarding the preference for off-pump versus on-pump coronary revascularization. Although the coronary trial indicates that the secondary endpoint outcomes favor on-pump surgery, the cost-effectiveness and significantly lower immediate and early complications in off-pump surgery make it favorable for the Indian population. To analyze patients who underwent coronary revascularization, specifically coronary artery bypass grafting (CABG), a retrospective five-year study was conducted. During the given duration, a total of 652 patients underwent CABG. The study revealed a positive correlation between diabetes, high body surface area (BSA), and preexisting renal dysfunction as strong predictors for converting off-pump coronary artery bypass surgery (OPCABG) to on-pump surgery coronary artery bypass surgery (ONCABG). Preoperative electrocardiographic (ECG) changes and the use of intra-aortic balloon pulsation (IABP) as a mechanical assist device were strongly associated with the incidence of conversion from OPCABG to ONCABG. Tight left main disease and ostial coronary disease indicate a progressive dysfunction during off-pump surgery, necessitating early conversion to on-pump surgery to avoid complications. The on-pump group had more adverse outcomes in regard to renal and neurological dysfunction, which can be attributed to pump-induced dysfunction. In such scenarios, a surgeon's preparedness to convert an OPCABG to an ONCABG can be swift and efficient. In anticipation of increased pump-related complications in the ONCABG group, a measured approach can be implemented to avoid adverse postoperative outcomes in high-risk patients.

Rapid cardiac ischemia detection with an epicardial graphene probe

Introduction

In this study, a new probe was designed to enable electrocardiography of a rotated heart during cardiac surgery when skin electrodes became non-functional. This probe adhered non-invasively to the epicardium and collected the ECG signal independently from the position of the heart. The study compared the accuracy of cardiac ischemia detection between classic skin and epicardial electrodes in an animal model.

Methods

Using six pigs, an open chest model was devised with cardiac ischemia induction by coronary artery ligation in two non-physiologic heart positions. Both the accuracy and the time of detection of electrocardiographic symptoms of acute cardiac ischemia were compared between skin and epicardial methods of signal collection.

Results

Heart rotation to expose either the anterior or the posterior wall resulted in a distortion or loss of the ECG signal collected by skin electrodes after coronary artery ligation, standard skin ECG monitoring did not reveal any ischemia symptoms. Attachment of an epicardial probe on the anterior and posterior walls helped in the recovery of the normal ECG wave. After ligation of the coronary artery, the epicardial probes recorded cardiac ischemia within 40 s.

Discussion

This study highlighted the effectiveness of ECG monitoring with epicardial probes in a rotated heart. It can be concluded that epicardial probes can detect the presence of acute ischemia of a rotated heart when skin ECG monitoring becomes ineffective.

Vasoactive inotropic score as a predictor of long-term mortality in patients after off-pump coronary artery bypass grafting

Increased vasoactive-inotropic score (VIS) is a reliable predictor of mortality and morbidity after cardiac surgery. Here, we retrospectively evaluated the association between VIS and adverse outcomes in adult patients after off-pump coronary artery bypass grafting (OPCAB). We included 2149 patients who underwent OPCAB. The maximal VIS was calculated for the initial 48 postoperative hours using standard formulae. The primary outcome was 1-year death. The composite adverse outcome was death, resuscitation or mechanical support, myocardial infarction, revascularization, new-onset atrial fibrillation, infection requiring antibacterial therapy, acute kidney injury, and stroke. Path-analysis was conducted using lactate and prognostic nutritional index (PNI). VIS was associated with 1-year death (odds ratio [OR] 1.07 [1.04–1.10], p < 0.001) and 1-year composite outcome (OR 1.02 [1.0–1.03], p = 0.008). In path-analysis, high VIS showed a direct effect on the increased risk of 1-year death and composite outcome. In the pathway using lactate as a mediating variable, VIS showed an indirect effect on the composite outcome but no significant effect on death. Low PNI directly affected the increased risk of 1-year death and composite outcome, and had an indirect effect on both outcomes, even when VIS was used as a mediating variable. In patients undergoing OPCAB, high VIS independently predicted morbidity and 1-year death. Patients with increased lactate levels following high VIS had an increased risk of postoperative complications, although not necessarily resulting in death. However, patients with poor preoperative nutritional status had an increased risk of unfavourable outcomes, including death, implying the importance of preoperative nutritional support.

Sex and age difference in risk factor distribution, trend, and long-term outcome of patients undergoing isolated coronary artery bypass graft surgery

BACKGROUND

Preoperative coronary artery disease risk factors (CADRFs) distribution and pattern may also have an important role in determining major adverse cardiovascular events (MACEs). In this study, we aimed to evaluate the CADRFs distribution and trend over 10 years and also the long-term outcome of CABG in different age-sex categories.

METHOD

In this registry-based serial cross-sectional study, we enrolled 24,328 patients who underwent isolated CABG and evaluated the prevalence of CADRFs according to sex and age. We used inverse probability weighting (IPW) to compare survival and MACE between the sexes. We also used Cox regression to determine each CADRFs effect on survival and MACEs.

RESULTS

In general, DLP (56.00%), HTN (53.10%), DM (38.40%), and positive family history (38.30%) were the most frequent risk factors in all patients. Prevalence of HTN, DLP, DM, obesity, and positive family history were all higher in women, all statistically significant. The median follow-up duration was 78.1 months (76.31-79.87 months). After inverse probability weighting (to balance risk factors and comorbidities), men had lower MACEs during follow-up (HR 0.72; 95% CI 0.57-0.91; P value 0.006) and there was no significant difference in survival between sexes. DM and HTN were associated with higher mortality and MACEs in both sexes.

CONCLUSION

Although DLP is still the most frequent CADRF among the CABG population, the level of LDL and TG is decreasing. Women experience higher MACE post CABG. Therefore, health care providers and legislators must pay greater attention to female population CADRFs and ways to prevent them at different levels.

A Risk Score for Predicting Long-Term Mortality Following Off-Pump Coronary Artery Bypass Grafting

BACKGROUND

Off-pump coronary artery bypass grafting (OPCAB) comprises 15-30% of all bypass grafting surgeries. The currently available perioperative scores such as Euroscore and STS score do not specifically predict long-term mortality after off-pump procedures. The neutrophil-to-lymphocyte ratio (NLR) is one of the new, easily accessible markers of inflammation with proven predictive value in cardiovascular diseases. We aimed to develop the first risk score for long-term mortality after OPCAB and to determine if the perioperative value of NLR predicts long-term mortality in OPCAB patients.

METHODS

In total, 440 consecutive patients with multivessel stable coronary artery disease undergoing OPCAB were recruited. Differential leukocyte counts were obtained by a routine hematology analyzer. Data regarding mortality during a median follow-up time of 5.3 years were obtained from the Polish National Health Service database. An independent population of 242 patients served as a validation cohort.

RESULTS

All-cause mortality was influenced by different clinical risk factors. In multivariate regression analysis, chronic obstructive pulmonary disease, stroke history, post-operative NLR and LVEF were independent predictors of mortality. Combing all independent predictors predicted long-term all-cause mortality with 68.5% sensitivity and 71.5% specificity (AUC = 0.704, p < 0.001). After weighing these variables according to their estimates in a multivariate regression model, we developed a score to predict mortality in patients undergoing OPCAB (PREDICT-OPCAB Score, ranging from 0 to 10). Patients with a high score were at higher risk of mortality within the median 5.3 years of follow-up (score 0-3: 8.3%; 4-6: 27.0%; 7-10: 40.0%; p < 0.001 for score 0-3 vs. 4-6 and 7-10). This association was confirmed in the validation cohort.

CONCLUSIONS

We developed and validated the first simplified risk score to predict mortality following OPCAB based on easily accessible clinical factors. This risk score can be used when obtaining a patient's informed consent and as an aid in determining treatment.

Predictors of unplanned 30-day readmissions after coronary artery bypass graft: a systematic review and meta-analysis of cohort studies

AIMS

Coronary artery bypass graft (CABG) is one of the most performed cardiac surgery globally. CABG is known to have a high rate of short-term readmissions. The 30-day unplanned readmission rate as a quality measure is associated with adverse health outcomes. This study aimed to identify and synthesize the perioperative risk factors for 30-day unplanned readmission after CABG.

METHODS AND RESULTS

We systematically searched seven databases and reviewed studies to identify all eligible English articles published from 1 October 1999 to 30 September 2019. Random-effect models were employed to perform pooled analyses. Odds ratio and 95% confidence interval were used to estimate the risk factors for 30-day unplanned readmission. The 30-day hospital readmission rates after CABG ranged from 9.2% to 18.9% in 14 cohort studies. Among preoperative characteristics, older adults, female, weight loss, high serum creatinine, anticoagulant use or dialysis, and comorbidities were found to be statistically significant. Postoperative complications, prolonged length of hospital stay, and mechanical ventilation were revealed as the postoperative risk factors for 30-day unplanned readmission. However, intraoperative risk factors were not found to be significant in this review.

CONCLUSION

Our findings emphasize the importance of a comprehensive assessment during the perioperative period of CABG. Healthcare professionals can perform a readmission risk stratification and develop strategies to reduce readmission rates after CABG using the risk factors identified in this review. Future studies with prospective cohort samples are needed to identify the personal or psychosocial factors influencing readmission after CABG, including perioperative risk factors.

On-Pump Beating Heart versus Off-Pump Coronary Artery Bypass Graft Surgery: Short-Term Follow-up Outcomes of a Single Center

Background and Aim: Novel surgical approaches are gaining attention in an attempt to overcome possible adverse events following coronary artery bypass graft (CABG) surgery. This single-center study aimed to evaluate and compare the early postoperative outcomes of on-pump beating-heart (OPBH-CABG) versus off-pump CABG surgery in similar risk groups with a total number of 1–2 grafts.

Methods: The records of a total of 229 patients who underwent non-emergency, primary, isolated, either OPBH-CABG (n = 32) or off-pump CABG (n = 197) surgery were retrospectively evaluated. Reported outcome measures included baseline data, the number of coronary artery grafts, prophylactic intra-aortic balloon pump, time of extubation from mechanical ventilation, duration of stay in the coronary ICU and hospital, as well as early postoperative complications, in-hospital and early postoperative mortality.

Results: The groups were identical with regards to age and BMI. The patients in the off-pump group received a higher number of grafts (1.84 ± 0.36 vs. 1.18 ± 0.39, p <0.0001). The OPBH-CABG group had a higher Euroscore II score (2.514 ± 1.68 vs. 1.706 ± 1.93, p = 0.021). The time to extubation after the surgery, postoperative length of ICU stay, and total length of hospital stay were similar between the groups (p = 0.2228; p = 0.098; p = 0.717, respectively). The incidence of arrythmia and atrial fibrillation was higher in the on-pump group (12.5% vs. 2.53%, p <0.05). One patient in the on-pump, and four patients in the off-pump groups deceased due to postoperative complications.

Conclusions: OPBH-CABG surgery is comparable to off-pump CABG in terms of early postoperative outcomes. In patients who underwent OPBH-CABG, the risk of arrythmia and atrial fibrillation should be of concern and solved with optimal strategies.

Association between the weekday on which coronary artery bypass graft surgery is performed and the 30-day mortality: A nationwide cohort study in South Korea

BACKGROUND

Postoperative mortality associated with elective coronary artery bypass graft (CABG) surgery may reportedly increase as the weekday of surgery approaches the weekend. We aimed to investigate the potential effect of the weekday of CABG surgery on the 30-day mortality.

METHODS

This population-based cohort study analyzed data obtained from the South Korea national health insurance service database. The cohort included all adult patients diagnosed with ischemic heart disease (International Classification of Diseases-10 codes I20*-I25*) who underwent isolated and elective CABG surgery from January 2012 to December 2017.

RESULTS

Of the 13,556 patients included in the analysis, 595 (4.4%) died within 30 days after CABG surgery. In a multivariable Cox model, the 30-day mortality of patients who underwent CABG surgery later in the week (Wednesday-Friday) was not significantly associated with the weekday of surgery as similar to those who underwent surgery early in the week (Monday-Tuesday) (hazard ratio [HR]: 1.14, 95% confidence interval [CI]: 0.97-1.34; p = .109). Multivariable sensitivity analysis revealed that CABG surgery on Friday was associated with a 1.40-fold higher hazard of 30-day mortality (HR: 1.40; 95% CI: 1.09-1.80; p = .008) than CABG surgery on Monday.

CONCLUSIONS

This South Korean population-based cohort study revealed that relative to surgery early in the week (Monday-Tuesday), CABG surgery later in the week (Wednesday-Friday) was not associated with higher 30-day mortality. However, using surgery on Monday as a reference, CABG surgery on Friday was associated with higher 30-day mortality. Future studies must confirm these findings.