Emergency Coronary Artery Bypass Graft Surgery for Acute Coronary Syndrome: Beating Heart Versus Conventional Cardioplegic Cardiac Arrest Strategies

Emergency coronary artery bypass grafting using minimized versus standard extracorporeal circulation--a propensity score analysis

Background

The impact of minimized extracorporeal circulation (MECC) for emergency revascularization remains controversial.

Methods

A total of 348 patients underwent emergency CABG with MECC (n=146) or conventional extracorporeal circulation (CECC; n=175) between January 2005 and December 2010. Using propensity score matching after binary logistic regression, 100 patients, who underwent CABG with MECC could be matched with 100 patients, who underwent CABG with CECC. Primary outcome was 30-day mortality.

Results

Unadjusted 30-day mortality was 14.8% in patients with CECC and 6.9% in those with MECC (mean difference −7.9%; p=0.03). The adjusted mean difference (average treatment effect of the treated, ATT) after matching was −1.0% (95% CI −8.6 to 7.6; p=1.0). Intensive care unit stay (adjusted mean difference 1.0; 95% CI −0.2 to 3.2; p=0.70) and hospital stay (adjusted mean difference 1.0; 95% CI −2.0 to 3.6; p=0.40) did not show significant differences between both groups. The adjusted mean difference for postoperative low cardiac output syndrome was −1.1% (95% CI −7.3 to 7.1; p=0.83) without significant differences between CECC and MECC. Postoperative mechanical ventilation time, drain loss, postoperative rethoracotomy, postoperative neurological events, new onset renal replacement therapy and respiratory failure also had insignificant average treatment effects of the treated. In addition, all average treatment effects (ATEs) did not significantly differ between both groups.

Conclusion

Using propensity score estimation and matching, we did not observe significant differences in terms of survival and further outcomes in patients who undergo emergency CABG with CECC or MECC, but our results call for further analysis.

Changes in anti-heat shock protein 27 antibody and C-reactive protein levels following cardiac surgery and their association with cardiac function in patients with cardiovascular disease

The relationship between serum anti-heat shock protein (Hsp)27 antibody and high sensitive C-reactive protein (hs-CRP) levels and indices of cardiac function were investigated in patients undergoing coronary artery bypass grafting (CABG) or heart valve replacement. The changes in anti-Hsp27 antibody titers and hs-CRP levels were compared among patients undergoing off-pump and on-pump CABG or valvular heart replacement. Fifty-three patients underwent off-pump, on-pump CABG, and heart valvular replacement in each group. Serum anti-Hsp27 titers and hs-CRP values were measured 24 h before and after the operation and at discharge. Echocardiography was performed before surgery and before discharge. The results were compared with values from 83 healthy controls. hs-CRP levels increased and anti-Hsp27 antibody decreased following surgery (P < 0.001 and P < 0.05, respectively), although these changes were independent of operative procedure (P = 0.361 and P = 0.120, respectively). Anti-Hsp27 antibody levels were higher at the time of discharge (P = 0.016). Only in coronary patients were anti-Hsp27 antibody levels negatively associated with E/E' (r = -0.268, P = 0.022), a marker of pulmonary capillary wedge pressure. In conclusions, anti-Hsp27 antibody levels are associated with indices of cardiac function in coronary patients. Cardiopulmonary bypass had no significant effect on the induction of changes in anti-Hsp27 levels. Moreover, anti-Hsp27 antibody levels fell in all groups postoperatively; this may be due to the formation of immune complexes of antigen-antibody, and antibody levels were higher at the time of discharge.

[Myocardial revascularization]

Coronary artery disease (CAD) is a leading cause of morbidity and mortality in western countries and is of significant socio-economic importance due to its increasing prevalence. Until percutaneous coronary interventions (PCI) were established, CAD could only be treated by surgical revascularization or pharmacological therapy. In-stent restenosis remains a major problem after stent implantation. However, the use of new materials and stent coatings have led to a significant reduction in in-stent restenosis. Thus, surgical revascularization and PCI are currently of equal value for the treatment of CAD. The decision-making for PCI or surgical revascularization depends on various factors such as number of diseased vessels, complexity of the coronary stenoses, concomitant diseases, and the patient's general condition. The therapeutic regime of every patient should be adjusted to the recommendations of the European and German Society for Cardiology, while controversial and complex cases should be discussed in an interdisciplinary case conference ("heart team").

Surgery for chronic total occlusion of the left main coronary artery

BACKGROUND AND OBJECTIVES

Chronic total occlusion of the left main coronary artery (LMCA) is a rare condition, and the information on surgical experiences is limited. Although total occlusion of the LMCA is accompanied by well-developed collateral circulation, the condition of circulation is unstable during manipulation of the heart. We report our experience with revascularization in cases with total occlusion of the LMCA using the on-pump beating-heart (OnP-BH) technique.

DESIGN AND SETTING

Retrospective case review of patients treated at The First Affiliated Hospital of China Medical University over a 10-year period (1999 to 2009).

PATIENTS AND METHODS

The on-pump coronary artery bypass grafting with the beating heart was applied to 8 patients with chronic total occlusion of the LMCA. The extracorporeal circulation period, intubation duration, intensive care unit stay period, discharge period, preoperative and postoperative treatments, and follow-up were observed.

RESULTS

The mean extracorporeal circulation period was 80.4 (19.7) minutes. The mean intubation duration was 13.0 (4.6) hours. The mean intensive care unit stay period was 3.2 (0.7) days, and the mean discharge period was 16.8 (3.3) days. No perioperative myocardial infarction occurred. The mean follow-up period was 50.9 (34.8) months. All patients were asymptomatic, and no deaths were recorded during the follow-up period. The results of echocardiography showed improvement in the left ventricular function.

CONCLUSIONS

The OnP-BH myocardial revascularization seems to be a valid alternative for chronic total occlusion of the LMCA.

Graft patency and late outcomes for patients with ST-segment elevation myocardial infarction who underwent coronary surgery

Objective: The aim of our study was to assess the long-term clinical outcomes and the grafts patency rates of patients with ST-segment elevation myocardial infarction (STEMI) who underwent urgent or emergency coronary artery bypass grafting (CABG).

Materials: Participants in two previous studies comprising 207 STEMI patients undergoing on-pump (145 patients) or off-pump (62 patients) coronary artery bypass graft (CABG) surgery in our institution were prospectively followed to assess late mortality, graft patency, and major adverse cardiac-related event (MACE) rates. Graft patency was evaluated by multi-detector computed tomography angiography 64-slice scan. Mean times of graft implantation were 38±16 months and 37±14 months in on-pump and off-pump, respectively. Follow-up data were obtained in all patients and was 100% complete.

Results: Late mortality rate was 7.4% (10 patients) in the on-pump and 6.5% (4 patients) in off-pump groups (p=0.45). Five-year overall survival rate (±SE) was 93.5±2.1% and 92.6±1.9% in the off-pump vs on-pump, respectively. Five years’ freedom from cardiac-related death was 94.9±2.9% in the on-pump group vs 96.8±3.2% in the off-pump group (p=0.25). Five years’ freedom from cardiac-related events was 89.7±1.6% in the on-pump group versus 93.5±1.8% in the off-pump group (p=0.32). In all patients, a total of 449/491 (91.5%) grafts were patent. Percentages of overall grafts classified as patent were similar in the on-pump group (90.7% - 322/355 conduits) versus the off-pump group (91% - 133/146 conduits). Graft patency rates were also similar between the two groups with regard to arterial and saphenous vein conduits, and with regard to different branches of the coronary arteries grafted.

Conclusion: Our data suggest that off-pump CABG patients have the same late mortality, MACEs, and graft patency rates as conventional cardioplegic cardiac arrest CABG patients. In our opinion, urgent or emergency CABG for patients with STEMI can be done either way.

Beating-heart coronary artery bypass surgery with the help of mini extracorporeal circulation for very high-risk patients

Background: Left ventricle dysfunction and co-morbidities are responsible for a large number of complications after coronary artery bypass graft (CABG) surgery. The best strategy for these patients, including the use or not and type of extracorporeal circulation (ECC), the use of minimized ECC (MECC), or conventional ECC (CECC), remains unclear. The aim of the present study was to investigate the potential effect of on-pump beating-heart (OPBH) surgery with the help of MECC for CABG in patients with a high-risk EuroSCORE and to compare this strategy to three other different procedures, including OPCAB and MECC or CECC with cardiac arrest.

Methods: Patients were included if their EuroSCORE was strictly >" xbd="1427" xhg="1404" ybd="1477" yhg="1440"/>9. Four groups were retrospectively compared: an OPCAB, an OPBH, a MECC and a CECC group under cardiac arrest.

Results: 214 patients, mean age 74.26 ± 8.5 years, 68.7% male, were operated. Mean EuroSCORE was 12.1 ± 2.9, left ventricular (LV) function 37.4 ± 12.3%, recent myocardial infarction (MI) 49.5%, renal failure 48.1%, chronic obstructive pulmonary disease (COPD) 42.2%, and peripheral vascular disease (PVD) 55.6%. Mean number of grafts per patient was 2.4 ± 0.7. Our study showed that it was possible, in very high-risk patients, to carry out revascularisation with OPBH similar to that using MECC or CECC under cardiac arrest (p=NS). This technique reduces troponin release (3.23 vs 6.56, p<0.01), postoperative myocardial complications (2% vs 8%, p<0.01), cardiotonic drug prescription (15.7% vs 31.3%, p<0.01), ventilation time (4.57H vs 6.48H, p<0.01) and length of stay (LOS) in ICU (2.16 vs 2.53, p=0.02).

Conclusion: The OPBH method seems to be safe, secure and effective in this population of very high-risk patients, reducing early complications and multi-organ failure. OPBH surgery, combining MECC without aortic cross-clamping, makes it possible to perform complete revascularization and is an interesting alternative for CABG in high-risk patients.

Beating-heart valve surgery: is the introduction of lung perfusion/ventilation the next step?

Myocardial and pulmonary ischemia during cardiopulmonary bypass has been associated with postoperative cardiac and pulmonary dysfunction, as well as poor outcomes. Beating-heart valve surgery utilizing continuous coronary perfusion with warm oxygenated blood via the antegrade/retrograde routes, is a novel strategy for myocardial protection. Conceptually, it is proposed that maintenance of pulmonary perfusion and ventilation during the cardiopulmonary bypass period also might be advantageous. The most current evidence regarding these evolving techniques and further areas of research are discussed in this article.

Early antiplatelet therapy in coronary artery bypass grafting: a calculated benefit

Studies have demonstrated that antagonists of platelet activity, including aspirin and clopidogrel, reduce the risk of major adverse events in patients with acute coronary syndromes. Although antiplatelet agents also convey an increased risk of bleeding, particularly in patients proceeding to coronary artery bypass graft surgery, in most cases, the benefits of early initiation of antiplatelet therapy outweigh the risks. The purpose of this review is to distinguish perceived and actual risk versus the benefit associated with early antiplatelet therapy to help clinicians make informed decisions on using these agents in an acute setting where patients may require coronary artery bypass grafting.

Off-pump Coronary Artery Bypass is a Safe Option in Patients Presenting as Emergency

Introduction: The applicability of off-pump coronary-artery bypass (OPCAB) in patients who present as emergency remains controversial. Herein, we explore the efficacy and safety of OPCAB in patients who were indicated for emergency surgery. Materials and Methods: Between 2002 and 2007, a total of 282 patients underwent OPCAB, of which 68 were presented as emergency. This cohort (group A) was compared to 68 patients who had traditional on-pump coronary artery bypass grafting (CABG, group B) under emergency indications during the same period of time. Baseline demographics, intraoperative data and postoperative outcomes were analysed. Results: Preoperative demographics were comparable in both groups. Mortality during the first 30 days was comparable in both groups and no stroke occurred in the whole series. Patients in group A had significantly less pulmonary complications (4.4% vs 14.7%, P= 0.04), less ventilation time (30.3 ± 33.6 hours vs 41.5 ± 55.4 hours, P = 0.18) and were less likely to have prolonged ventilation, (19.1% vs 35.3%, P = 0.03). Similarly, OPCAB patients had less postoperative renal-failure/dysfunction (5.9% vs 8.8%, P = 0.51) and required less inotropic support (66.2% vs 88.2%, P = 0.002), bloodtransfusions (23% vs 86.8%, P <0.0001), and atrial- (17.6% vs 35.3%, P = 0.02) or ventricular-pacing (17.6% vs 41.2%, P = 0.002). Although the number of diseased vessels was comparable in both groups, patients in group A received less distal anastomoses. (2.78 ± 1.19 vs 3.41 ± 0.89, P = 0.002). Similarly, complete revascularisation was achieved less frequently in group A (76.5% vs 94.1%, P = 0.004). Conclusion: OPCAB strategy is a safe and efficient in emergency patients with reasonable good short-term postoperative outcomes. Keywords: Cardiac surgery, Coronary artery disease, Off-pump coronary-artery bypass

Off-pump versus on-pump coronary artery bypass grafting in acute coronary syndrome: a clinical analysis

Background

Although off-pump coronary artery bypass (OPCAB) surgery has many beneficial effects compared with on-pump surgery, switch to on-pump surgery has significantly higher risks of operative mortality. Benefits of OPCAB over on-pump surgery strategies concerning myocardial revascularization are still debatable. We have aimed to develop an "algorithm of off-pump surgical strategy" on preventing conversion to on-pump. This clinical study reports our clinical outcome of OPCAB in patients with acute coronary syndrome.

Methods

Between January 2006 and December 2008, 198 patients with acute coronary syndrome were enrolled in the study. Decision of OPCAB (142 patients) or on-pump surgery (56 patients) was made according to patients' present clinical status and our surgical background. Cardiac enzymes, duration of the surgery, graft numbers, stay in intensive care unit were recorded.

Results

OPCAP group has shorter operation time (82.78 min versus 164.22 min, p < 0.001), lesser necessity for intra-aortic balloon pumping (3.5% versus 12.5%, p = 0.053), shorter duration of intensive care unit stay (p < 0.05) and hospital stay (p < 0.001) compared to on-pump patients. EuroSCORE level was lower in OPCAP group (p < 0.001). None of the patients of OPCAB group required conversion to on-pump technique.

Conclusions

The patients who admitted to the hospital with acute coronary syndrome within "golden hours" (within 6 hours after onset) had a greater chance for OPCAB surgery. This study proves that EuroSCORE is likely to be an important factor in deciding which surgical technique to use, but a further investigation is needed to verify. According to our findings, a careful evaluation of coronary angiography, hemodynamic status, quality of target coronary vessel and timing of surgery are important for OPCAB surgery to avoid conversion to on-pump. By a careful systematic evaluation of the patients as explained with this article, it can be prevent or reduce conversion to on-pump surgery during OPCAB surgery.

Timing of revascularization after acute myocardial infarction

The optimal timing of surgical revascularization after acute myocardial infarction remains controversial. Higher mortality after emergency coronary artery bypass has been documented. We retrospectively reviewed 278 patients who underwent coronary artery bypass between 2005 and 2007. The time from onset of myocardial infarction to surgical revascularization was the basis for dividing patients into 3 groups: surgery was performed within 24 h in group 1, at 24-72 h in group 2, and after 14 days in group 3. There was a definite relationship between the timing of revascularization and the outcome of surgery. Group 1 had a mortality rate of 11.7%, group 2 had 7% mortality, and group 3 had 2.5% mortality. Group 1 had the highest incidence of postoperative complications. Surgical revascularization within 24 h of acute myocardial infarction was associated with significantly higher risks of mortality and morbidity than procedures performed after 72 h.

Clopidogrel in the management of acute coronary syndromes: indications, results, obstacles

Atherothrombosis is the underlying pathology of the acute coronary syndromes (ACS), in which platelet activation plays a key role. Therefore, antiplatelet therapy is an essential component of guideline-recommended ACS management. Considerable evidence clearly demonstrates the benefits of the antiplatelet agent clopidogrel in reducing mortality, decreasing recurrent cardiovascular events, and increasing arterial patency in ACS patients. Despite this evidence, data from patient registries and clinical initiatives such as CRUSADE (Can Rapid stratification of Unstable angina Suppress ADverse outcomes with Early implementation of the American College of Cardiology/American Heart Association guidelines) and GRACE (Global Registry of Acute Coronary Events) indicate that clopidogrel is underused in patients with ACS. This is especially true for patients receiving conservative medical management, many of whom have significant risk for recurrent ischemic events. The purpose of this review is to compare "real-life" clopidogrel therapy with evidence-based guidelines, and to highlight clinical factors that drive clopidogrel implementation or provide barriers to its use in ACS patients.

[Coronary artery bypass grafting in conscious patients: a procedure with a perspective?]

Patients undergoing coronary artery bypass grafting increasingly show severe co-morbidities, which can negatively affect the outcome. Recent developments in cardiac surgery have therefore focused on minimizing the invasiveness of the procedure by revascularization on the beating heart without cardiopulmonary bypass, and by reducing surgical trauma using smaller surgical incisions. Progress in minimally invasive cardiac surgery has led to minimally invasive anesthesia, i.e. using high thoracic epidural anesthesia as the sole technique in the conscious patient (awake coronary artery bypass grafting, ACAB). Published data on ACAB procedures in smaller cohorts have demonstrated that the procedure is safe. Significant complications occurred in 7.1% of patients. A particular cause of concern during ACAB surgery is the development of spinal epidural hematoma the risk of which has been estimated to be as high as 1:1,000. A thorough risk-benefit analysis has therefore to be made. Currently, ACAB surgery remains limited to few specialized centers and highly selected patients.

Predictors and Outcomes of Coronary Artery Bypass Grafting in ST Elevation Myocardial Infarction

BACKGROUND

Treatment of ST-elevation myocardial infarction has undergone great evolution since introduction of percutaneous coronary intervention (PCI). The purpose was therefore to assess the outcome of patients with ST-elevation myocardial infarction undergoing surgical revascularization with coronary artery bypass grafting (CABG).

METHODS

A total of 138 consecutive patients with ST-elevation myocardial infarction underwent CABG therapy between January 2000 and January 2007 at our institution. Prospectively recorded preoperative, intraoperative, and postoperative data were retrospectively screened for in-hospital mortality and major adverse cardiac events (MACE).

RESULTS

The delay between the onset of ST-elevation myocardial infarction symptoms and CABG procedures was within 6 hours in 37 patients, 7 to 24 hours in 21, 1 to 3 days in 15, 4 to 7 days in 24, and 8 to 14 days in 41 patients. Cardiogenic shock (Killip class > or = III) was present in 38 patients (28%), and 37 patients (27%) were referred for CABG after failed PCI. Overall in-hospital mortality was 8.7%, but mortality varied between 10.8% (< or = 6 hours), 23.8% (7 to 24 hours), 6.7% (1 to 3 days), 4.2% (4 to 7 days), and 2.4% (8 to 14 days), depending on time interval from symptom onset to operation. Overall, more nonsurvivors were women (58% versus 23%; p < 0.01), had higher preoperative cardiac troponin I levels (13.2 +/- 9.8 versus 4.5 +/- 4.2 ng/ml; p < 0.0001), and were more frequently in cardiogenic shock (83% versus 22%; p < 0.0001). Unadjusted univariable and risk-adjusted multivariable logistic regression analysis revealed age, female sex, preoperative cardiac troponin I levels, and cardiogenic shock to be the most potent predictors of in-hospital death and MACE.

CONCLUSIONS

CABG in ST-elevation myocardial infarction can be performed with acceptable risk by incorporating adequate management strategies. However, female sex, preoperative cardiac troponin I level, preoperative cardiogenic shock, and time to operation are major variables of mortality and morbidity results.