On-pump versus off-pump surgical revascularization in patients with acute coronary syndromes: Analysis from the Acute Catheterization and Urgent Intervention Triage Strategy trial

Complete surgical revascularization after NSTEMI and unstable angina in patients with multivessel coronary artery disease: Institutional experience

INTRODUCTION

The feasibility and standardization of coronary artery bypass grafting (CABG) in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) and unstable angina (UA) remain topics of ongoing debate. In this study, feasibility and early-term outcomes of CABG in patients with NSTE-ACS and UA were discussed.

METHODS

This study enrolled 79 patients who underwent on-pump CABG with complete revascularization between January 2020 and May 2022. the survival rates analyzed using Kaplan Meier test with log rank test. The p value of statistical significance was taken as below 0.05.

RESULTS

Preoperatively, the patients had a mean age of 60.9 years and a BMI of 28.0. The medical history included hypertension (50.6%), peripheral arterial disease and atrial fibrillation (12.7%), and other comorbidities such as COPD (22.8%) and type 2 diabetes mellitus (44.3%). Intraoperatively, the mean distal anastomosis count was 3.4, with average cardiopulmonary bypass and aortic cross-clamp times of 84.0 and 49.0 min, respectively. Early-term outcomes revealed low rates of mortality (2.5%) and complications such as myocardial infarction (1.3%), acute kidney injury (5.1%) and transient ischemic attack (5.1%). Post-discharge outcomes demonstrated low cardiac and all-cause mortality rates (2.5% and 3.8%, respectively) and a high overall survival rate (93.7%) at 12-month follow-up.

CONCLUSION

This study demonstrated the feasibility and positive outcomes of complete surgical revascularization in patients with UA and NSTE-ACS. It showed no graft occlusion or stroke, low complication rates and promising survival outcomes. Further research is needed for confirmation and to establish the procedure's efficacy and safety in this patient population.

Coronary artery bypass surgery for acute coronary syndrome: A network meta-analysis of on-pump cardioplegic arrest, off-pump, and on-pump beating heart strategies

BACKGROUND

Coronary artery bypass grafting (CABG) in the setting of an acute coronary syndrome is a high-risk procedure, and the best strategy for myocardial revascularisation remains debated. This study compares the 30-day mortality benefit of on-pump CABG (ONCAB), off-pump CABG (OPCAB), and on-pump beating heart CABG (OnBHCAB) strategies.

METHODS

A systematic search of three electronic databases was conducted for studies comparing ONCAB with OPCAB or OnBHCAB in patients with acute coronary syndrome (ACS). The primary outcome, 30-day mortality, was compared using a Bayesian hierarchical network meta-analysis (NMA). A random effects consistency model was applied, and direct and indirect comparisons were made to determine the relative effectiveness of each strategy on postoperative outcomes.

RESULTS

One randomised controlled trial and eighteen observational studies fulfilling the inclusion criteria were identified. A total of 4320, 5559, and 1962 patients underwent ONCAB, OPCAB, and OnBHCAB respectively. NMA showed that OPCAB had the highest probability of ranking as the most effective treatment in terms of 30-day mortality (odds ratio [OR], 0.50; 95% credible interval [CrI], 0.23-1.00), followed by OnBHCAB (OR, 0.62; 95% CrI, 0.20-1.57), however the 95% CrI crossed or included unity. A subgroup NMA of nine studies assessing only acute myocardial infarction (AMI) patients demonstrated a 72% reduction in likelihood of 30-day mortality after OPCAB (CrI, 0.07-0.83). No significant increase in rate of stroke, renal dysfunction or length of intensive care unit stay was found for either strategy.

CONCLUSIONS

Although no single best surgical revascularisation approach in ACS patients was identified, the significant mortality benefit with OPCAB seen with AMI suggests high acuity patients may benefit most from avoiding further myocardial injury associated with cardiopulmonary bypass and cardioplegic arrest.

Surgical revascularization for acute coronary syndromes: a report from the North Rhine-Westphalia surgical myocardial infarction registry

OBJECTIVES

The aim of this was to analyse current outcomes in patients referred to coronary artery bypass grafting (CABG) for acute coronary syndromes (ACSs), including ST-elevation or non-ST-elevation ACS (non-ST-segment elevation myocardial infarction) or unstable angina.

METHODS

Patients (n = 2432) undergoing CABG for ACS between January 2010 and December 2017 were prospectively entered into a surgical myocardial infarction registry in North Rhine-Westphalia, Germany. Key end points were in-hospital all-cause mortality (IHM) and major adverse cardio-cerebral events (MACCE). Predictors for IHM and MACCE were analysed by multivariable logistic regression.

RESULTS

Patients (78% males) were referred for CABG for unstable angina (25%), non-ST-segment elevation myocardial infarction (50%), and ST-segment elevation myocardial infarction (25%). The mean patient age was 68 ± 11 years, logistic EuroSCORE was 19 ± 18% and three-vessel and left main stem diseases were diagnosed in 81% and 45% of patients, respectively. On-pump CABG with cardiac arrest or beating heart was performed in 92% and 2%, respectively, with only 6% off-pump surgery and 6% multiple arterial revascularization (3.1 ± 1.0 grafts, 93% left internal thoracic artery). Emergency CABG was performed in 23% of patients (42% in ST-segment elevation myocardial infarction; P < 0.001). The total IHM and MACCE rates were 8.1% and 17.5% and were highest in ST-segment elevation myocardial infarction patients with 12.6% and 28.5%, respectively (P < 0.001). Key predictors for IHM and MACCE were female gender, elevated troponin, left ventricular ejection fraction, inotropic support, logistic EuroSCORE, cardiopulmonary bypass and aortic clamp time and the need for emergency CABG.

CONCLUSIONS

Surgical myocardial revascularization in patients with ACS is still linked to substantial in-hospital mortality. Emergency CABG for patients with ACS was associated with poorer outcomes.

Anatomically correct three-dimensional coronary artery reconstruction using frequency domain optical coherence tomographic and angiographic data: head-to-head comparison with intravascular ultrasound for endothelial shear stress assessment in humans

AIMS

To develop a methodology that permits accurate 3-dimensional (3D) reconstruction from FD-OCT and angiographic data enabling reliable evaluation of the ESS distribution, and to compare the FD-OCT-derived models against the established models based on angiography/IVUS.

METHODS AND RESULTS

Fifteen patients (17 coronary arteries) who underwent angiography, FD-OCT and IVUS examination during the same procedure were studied. The FD-OCT and IVUS lumen borders were placed onto the 3D luminal centreline derived from angiographic data. Three-dimensional geometry algorithms and anatomical landmarks were used to estimate the orientation of the borders appropriately. ESS was calculated using computational fluid dynamics. In 188 corresponding consecutive 3-mm segments, FD-OCT- and IVUS-derived models were highly correlated for lumen area (r=0.96) and local ESS (r=0.89) measurements. FD-OCT-based 3D reconstructions had a high diagnostic accuracy for detecting regions exposed to proatherogenic low ESS identified on the IVUS-based 3D models, considered as the gold standard (receiver operator characteristic area under the curve: 94.9%).

CONCLUSIONS

FD-OCT-based 3D coronary reconstruction provides anatomically correct models and permits reliable ESS computation. ESS assessment in combination with the superior definition of plaque characteristics by FD-OCT is expected to provide valuable insights into the effect of the haemodynamic environment on the development and destabilisation of high-risk plaques.

Coronary Artery Bypass Grafting During Acute Coronary Syndrome: Outcomes and Comparison of Off-Pump to Conventional Coronary Artery Bypass Grafting at a Veteran Affairs Hospital

OBJECTIVE

The management of acute coronary syndrome (ACS) has evolved dramatically over the last 50 years. Currently, management includes a multidisciplinary approach potentially including catheter-based therapy, surgery, or purely medical management. Where surgical therapy is indicated, data regarding long-term outcomes are limited. In particular, little data exist regarding on-pump (conventional coronary artery bypass grafting, cCABG) versus off-pump (OPCABG) outcomes for this group.

METHODS

A retrospective review of prospectively collected data was undertaken. Patients undergoing isolated CABG from January 2000 to December 2011 with ACS were identified (n = 271); non-ACS patients (n = 854) were established as a control. Data were analyzed with a χ or a t test, where appropriate. Survival was compared using Kaplan-Meier analysis and Cox proportional hazards model.

RESULTS

Thirty-day mortality between the ACS and the control groups was similar; however, long-term mortality was worse for the ACS group (P = 0.032; median follow-up, 5.5 years). Length of stay and composite morbidity were higher in the ACS group (P < 0.01). Subgroup analysis of ACS patients (OPCABG vs cCABG) demonstrated worse preoperative comorbidities in the OPCABG group, but similar 30-day and long-term mortality. However, the cCABG group had higher rates of reoperation (P = 0.034) and longer length of stay (P = 0.017) and operative time (P < 0.0001). Cox proportional hazards model was applied. Risk factors for the non-ACS cohort included age, diabetes, OPCABG, and ACS (P < 0.05). Among the ACS cohort, only age remained a statistically significant factor (P < 0.0001).

CONCLUSIONS

ACS appears to negatively impact long-term, but not short-term, mortality. Within the ACS group, OPCABG compares favorably to cCABG in the long-term and also improves short-term morbidity.

On-pump beating heart coronary revascularization: Is it valid for emergency revascularization?

BACKGROUND

On-pump beating heart coronary artery bypass grafting (CABG) may be considered as an alternative to the conventional on-pump surgery in patients presenting with acute coronary syndrome requiring emergency revascularization. This study reports our clinical experience and early outcomes with the on-pump beating heart coronary surgery on patients with acute coronary syndrome.

DESIGN AND SETTINGS

A retrospective study conducted from August 2009 to October 2015, in a regional training and research hospital in Turkey.

METHODS

A total of 1432 patients underwent isolated CABG at our institution. A total of 316 of these patients underwent the on-pump beating heart procedure without cardioplegic arrest by the same surgeon.

RESULTS

The time interval from the onset of acute myocardial infarction to CABG was 10 (2.2) hours. The mean number of grafts was 3.0 (0.6). Hospital mortality was 2.9% (9 patients). Twelve patients had low cardiac output syndromes after surgery. Eight of them had renal dysfunction but none of them needed hemodialysis. The mean intensive care unit stay was 3 (2) days and the mean hospital length of stay was 7 (4) days.

CONCLUSION

We think that the on-pump beating heart revascularization technique can be a good choice for emergency CABG of high-risk patients with a multivessel coronary artery disease.

Del Nido Cardioplegia can be safely administered in high-risk coronary artery bypass grafting surgery after acute myocardial infarction: a propensity matched comparison

OBJECTIVE

Del Nido (DN) cardioplegia solution provides a depolarized hyperkalemic arrest lasting up to 60 minutes, and the addition of lidocaine may limit intracellular calcium influx. Single-dose DN cardioplegia solution may offer an alternative myocardial protection strategy to multi-dose cold whole blood (WB) cardioplegia following acute myocardial infarction (AMI).

METHODS

We retrospectively reviewed 88 consecutive patients with AMI undergoing coronary artery bypass (CABG) surgery with cardioplegic arrest between June 2010 to June 2012. Patients exclusively received WB (n = 40, June 2010-July 2011) or DN (n = 48, August 2011-June 2012) cardioplegia. Preoperative and postoperative data were retrospectively reviewed and compared using propensity scoring.

RESULTS

No significant difference in age, maximum preoperative serum troponin level, ejection fraction, and STS score was present between DN and WB. A single cardioplegia dose was given in 41 DN vs. 0 WB patients (p < 0.001), and retrograde cardioplegia was used 10 DN vs. 31 WB patients (p < 0.001). Mean cardiopulmonary bypass and cross clamp times were significantly shorter in the DN group versus WB group. Transfusion rate, length of stay, intra-aortic balloon pump requirement, post-operative inotropic support, and 30-day mortality was no different between groups. One patient in the WB group required a mechanical support due to profound cardiogenic shock.

CONCLUSIONS

DN cardioplegia may provide equivalent myocardial protection to existing cardioplegia without negative inotropic effects in the setting of acute myocardial infarction.

Off-pump coronary surgery: current justifications

Although the literature has failed to project an overall superiority of off-pump vs. on-pump surgery, nevertheless, small randomized control trials and large meta-analysis studies have concluded that the incidence of a stroke is less than 1 % when anaortic off-pump techniques are advocated in patients with diseased ascending aorta. Furthermore, off-pump techniques or their combination with hybrid procedures may lead to a reduction of adverse outcome in the aged high-risk population with concomitant poor left ventricular function and co-morbidities. However, despite this, controversy still exists among the cardiac surgery community in terms of the benefit of this technique and its safety; hence, off-pump is becoming out of fashion. In this review paper, by looking at a "marginal group of patients" (elderly, high risks, atherosclerotic aortas) we attempt to re-establish and justify this technique and re-invent its usage.

"Polarizing" microplegia improves cardiac cycle efficiency after CABG for unstable angina

BACKGROUND

Myocardial protection during coronary artery bypass grafting (CABG) for unstable angina (UA) still represents a major challenge, ought to the risk for further ischemia/reperfusion injury. Few studies investigate the biochemical, hemodynamic and echocardiographic results of microplegia (Mic) in UA.

METHODS

Eighty UA-patients undergoing CABG were randomized to Mic (Mic-Group) or standard 4:1 blood Buckberg-cardioplegia (Buck-Group). Troponin-I and lactate were sampled from coronary sinus at reperfusion (T1), and from peripheral blood preoperatively (T0), at 6 (T2), 12 (T3) and 48 (T4) hours. Cardiac index (CI), indexed systemic vascular resistances (ISVR), Δp/Δt, cardiac cycle efficiency (CCE), and central venous pressure (CVP) were collected preoperatively (T0), and since Intensive Care Unit (ICU)-arrival (T1) to 24h (T5). Echocardiographic E-wave (E), A-wave (A), E/A, peak early-diastolic TDI-mitral annular-velocity (Ea), and E/Ea investigated the diastolic function and Wall Motion Score Index (WMSI) the systolic function, preoperatively (T0) and at 96h (T1).

RESULTS

Mic-Group showed lower troponin-I and lactate from coronary sinus (p=.0001 for both) and during the postoperative course (between-groups p=.001 and .0001, respectively). WMSI improved only after Mic (time-p=.001). Higher CI Δp/Δt and CCE (between-groups p=.0001), with comparable CVP and ISVR (p=N.S.) were detected after Mic. Diastolic function improved in both groups, but better after Mic (between-groups p=.003, .001, and .013 for E, E/A, and Ea, respectively). Mic resulted in lower transfusions (p=.006) and hospitalization (p=.002), and a trend towards lower need/duration of inotropes (p=.04 and p=.041, respectively), and ICU-stay (p=.015).

CONCLUSION

Microplegia attenuates myocardial damage in UA, reduces transfusions, improves postoperative systo-diastolic function, and shortens hospitalization.

Risk stratification in acute coronary syndromes

Accurate and readily available systems for risk stratification and a wide array of antithrombotic agents, on top of classical anti-ischemic drugs, provide the noninvasive cardiologist admitting the patient in the CCU with an effective and reliable armamentarium for the safe management of most patients with ACS. From the interventionalist's perspective, the immediate knowledge of the coronary anatomy yields the most valuable information to address the most appropriate treatment. The sooner angiography is performed the higher the benefit for patients at moderate to high risk, but if performed by expert teams and with the correct use of modern drugs and devices, the invasive approach has the potential to reduce costs and length of hospital stay also in low-risk patients. Although still some reluctance remains to equalize treatment strategies for patients with STEMI to those with NSTEMI, such differences will likely disappear in the near future with upcoming new evidence. Cardiac surgery may represent a life-saving alternative for patients presenting with NSTEMI evolving in cardiogenic shock or with mechanical complications, or in patients unsuitable for PCI or with failed PCI attempts. In stabilized conditions after the treatment of the culprit lesion, patients with severe multivessel disease may benefit from cardiac surgery to complete myocardial revascularization. Indications for CABG in this setting should be evaluated in the context of a local "heart team" or through prespecified protocols in centers without cardiac surgery on site.