On-Pump Beating-Heart Coronary Artery Bypass: A Propensity Matched Analysis

Minimally Invasive Coronary Artery Bypass Grafting in a Low-Risk Asian Cohort: A Propensity-Score Matched Study

INTRODUCTION

Minimally invasive coronary artery bypass grafting (MICS CABG) offers a new paradigm in coronary revascularization. This study aims to compare the outcomes of MICS CABG with those of conventional median sternotomy CABG (MS CABG) within a growing minimally invasive cardiac surgical program in Singapore.

METHODS

Propensity matching produced 111 patient pairs who underwent MICS CABG or MS CABG between January 2009 and February 2020 at the National University Heart Centre, Singapore. Minimally invasive direct coronary artery bypass surgery patients were matched to single- or double-graft MS CABG patients (Group 1). Multivessel MICS CABG patients were matched to MS CABG patients with equal number of grafts (Group 2).

RESULTS

Overall, MICS CABG patients experienced shorter postoperative length of stay (P<0.071). In Group 2, procedural duration (P<0.001) was longer among MICS CABG patients, but it did not translate to adverse postoperative events. Postoperative outcomes, including 30-day mortality, reopening for bleeding, new onset atrial fibrillation as well as neurological, pulmonary, renal, and infectious complications were comparable between MICS and MS CABG groups.

CONCLUSION

MICS CABG is a safe and effective approach for surgical revascularization of coronary artery disease and trends toward a reduction in hospital stay.

The outcomes of three different techniques of coronary artery bypass grafting: On-pump arrested heart, on-pump beating heart, and off-pump

OBJECTIVE

Conventional coronary artery bypass grafting (CABG) or on-pump arrested heart CABG (ONCAB) is a standard and simple technique. However, adverse effects can occur due to the use of aortic cross-clamp and cardiopulmonary bypass. Performing off-pump CABG (OPCAB) aims to avoid these adverse effects but may result in incomplete revascularization. On-pump beating heart CABG (ONBHCAB) combines the benefits of both ONCAB and OPCAB. This study focuses on comparing the short- and long-term outcomes of different CABG techniques.

METHOD

Retrospective observational cohort included 2,028 patients who underwent ONCAB, OPCAB, and ONBHCAB. The short-term outcomes including postoperative ischemic injury, hemodynamic functions, and adverse events were compared. The long-term outcomes were overall survival and the occurrence of major adverse cardiovascular events (MACE). Propensity score matching ensured comparability among the three patient groups.

RESULTS

After matching, there were no differences in baseline characteristics. Regarding ischemic injury, OPCAB showed the lowest peak cardiac enzyme levels (all p≤0.001). There were no statistically significant differences in the change of hemodynamic function (cardiac index) between the three groups (p = 0.158). Ten-year survival for OPCAB, ONBHCAB, and ONCAB were 80.5%, 75.9%, and 73.7%, respectively. OPCAB was associated with a significant reduction in mortality risk and MACE when compared to others (Mortality HR = 0.33, p = 0.001, MACE HR = 0.52, p = 0.004).

CONCLUSION

OPCAB implementation resulted in a lower occurrence of postoperative ischemic injury than ONCAB and ONBHCAB. No differences in postoperative hemodynamic function in all three techniques were observed. OPCAB respectively were preferable techniques beneficial for long-term outcomes.

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.

Factors affecting mortality after coronary bypass surgery: a scoping review

Objectives

Previous research reports numerous factors of post-operative mortality in patients undergoing isolated coronary artery bypass graft surgery. However, this evidence has not been mapped to the conceptual framework of care improvement. Without such mapping, interventions designed to improve care quality remain unfounded.

Methods

We identified reported factors of in-hospital mortality post isolated coronary artery bypass graft surgery in adults over the age of 19, published in English between January 1, 2000 and December 31, 2019, indexed in PubMed, CINAHL, and EMBASE. We grouped factors and their underlying mechanism for association with in-hospital mortality according to the augmented Donabedian framework for quality of care.

Results

We selected 52 factors reported in 83 articles and mapped them by case-mix, structure, process, and intermediary outcomes. The most reported factors were related to case-mix (characteristics of patients, their disease, and their preoperative health status) (37 articles, 27 factors). Factors related to care processes (27 articles, 12 factors) and structures (11 articles, 6 factors) were reported less frequently; most proposed mechanisms for their mortality effects.

Conclusions

Few papers reported on factors of in-hospital mortality related to structures and processes of care, where intervention for care quality improvement is possible. Therefore, there is limited evidence to support quality improvement efforts that will reduce variation in mortality after coronary artery bypass graft surgery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-022-01784-z.

On-pump beating heart versus off-pump myocardial revascularization-a propensity-matched comparison

Objective

On-pump beating heart (OP-BH) coronary artery bypass grafting (CABG) is often undertaken as an alternative between off-pump coronary artery bypass (OPCAB) and conventional on-pump coronary artery bypass grafting (On-pump CABG), especially in India. However, outcome data following OP-BH surgery is sparse. The aim of this study was to compare the outcomes of OP-BH CABG with OPCAB.

Methods

From our institutional database, all patients undergoing OP-BH CABG (n = 531) were identified. A propensity-matched cohort undergoing OPCAB (n = 531) was identified from the database. Nearest neighbor matching technique was used and the groups were matched for variables including age, gender, body mass index, EuroSCORE, history of recent myocardial infarction or unstable angina, hypertension, peripheral vascular disease, chronic obstructive airway disease, diabetes, pre-op renal impairment, pre-op neurological events, and left ventricular function.

Results

The propensity-matched groups were well matched in terms of baseline characteristics. The mean EuroSCORE was 3.17 and 3.20 in the OP-BH and the OPCAB groups. The unadjusted 30-day mortality in the propensity-matched OPCAB group was 2.07% (11/531) while mortality in the on-pump beating heart group was significantly higher at 6.9% (37/531). Multivariate analysis showed that OP-BH CABG was an independent risk factor for 30-day mortality as well as major adverse post-operative outcomes including renal, neurological, and respiratory outcomes and post-operative atrial fibrillation.

Conclusions

OP-BH CABG is associated with worse clinical outcomes compared to patients undergoing OPCAB.

On-pump beating heart versus conventional on-pump coronary artery bypass grafting on clinical outcomes: a meta-analysis

Background

A hybrid surgery method, on-pump beating heart coronary artery bypass graft (ON-BH CABG), is supposed to be a promising technology for coronary artery revascularization. Here, we conducted a comprehensive meta-analysis of the data derived from published studies on ON-BH CABG and conventional on-pump coronary artery bypass graft (C-CABG) to compare their short-term and long-term clinical outcomes.

Methods

We searched major electronic databases and 24 studies incorporating 6,862 patients (1,847 ON-BH CABG and 5,015 C-CABG) were included eventually, and 9 studies of them were focusing on high-risk patients.

Results

Compared with ON-BH CABG, C-CABG was associated with a higher risk in early mortality [odds ratio (OR), 1.45; 95% confidence interval (CI), 1.09 to 1.93; P=0.01], myocardial infarction (MI) (OR, 2.60; 95% CI, 1.41 to 4.78; P<0.01), low output syndrome (LOS) (OR, 2.56; 95% CI, 1.55 to 4.23; P<0.01), renal failure (OR, 1.84; 95% CI, 1.38 to 2.44; P<0.01). In contrast, there was no significant difference in long-term survival [hazard ratio (HR), 1.08; 95% CI, 0.81 to 1.43; P=0.60]. In systematic analysis of the studies in high-risk patients, ON-BH CABG showed a lower risk in terms of early mortality, intra-aortic balloon pump (IABP) usage, renal failure, hemodialysis, MI and pulmonary complication. No significant difference was observed in the long-term survival between ON-BH CABG and C-CABG.

Conclusions

With experienced and adept surgical team and mature ON-BH technology, ON-BH CABG may reduce the risk of postoperative death and complications in some patients. It might be an attractive alternative for high-risk patient populations.

Long-term Outcome 10 Years After Free Gastroepiploic Artery Graft for Coronary Artery Bypass Surgery

BACKGROUND

The long-term benefits of "free" gastroepiploic artery (GEA) grafts remain unclear. The aim of this study is to investigate the long-term patency and clinical results of en bloc free GEA grafts.

METHODS

Of the 1478 patients undergoing coronary artery bypass graft surgery at our institution between January 1997 and December 2009, 137 patients underwent en bloc free GEA grafting. Graft patency, late survival, and freedom from major adverse cardiovascular events were examined. Propensity score matching was used to compare the patency of free GEA grafts with the saphenous vein grafts, and 134 matched pairs were generated.

RESULTS

The early patency rate of free GEA grafts was 98.6%. The long-term patency rates of the free GEA grafts was 96.5% at 5 years, 95% at 10 years, and 86.6% at 15 years. In the 134 matched pairs, the long-term patency rates of free GEA grafts anastomosed to the right coronary artery were significantly higher than those of saphenous vein grafts to the right coronary artery (97% vs 91.8% at 5 years; 95.3% vs 79.6% at 10 years; 85.9% vs 61.7% at 15 years; P < .001). Survival was 94% at 5 years, 86.6% at 10 years, and 66.8% at 15 years; and freedom from major adverse cardiovascular events was 93.2% at 5 years, 91.3% at 10 years, and 73.1% at 15 years.

CONCLUSIONS

En bloc free GEA grafts had favorable long-term performance and can be considered as an effective option for patients who need to receive as many arterial grafts as possible.

On-pump beating-heart coronary artery bypass grafting in high-risk patients: A systematic review and meta-analysis

BACKGROUND

Operative technique for surgical myocardial revascularization in high-risk patients remains an argument of debate. On-pump coronary artery bypass graft (CABG) with cardioplegic arrest and off-pump CABG have intrinsic limitations. The hybrid approach of on-pump beating-heart CABG (OPBHC) has been proposed over the years with conflicting results. This systematic review and meta-analysis intends to summarize the contemporary literature.

METHODS

A literature search was conducted through major electronic databases. The systematic review provided a total of 279 articles, of those 17 studies were included in the present study.

RESULTS

Compared with on-pump CABG, OPBHC patients showed a preoperative higher risk profile but had reduced early mortality (risk ratio [RR], 0.59, 95% CI, 0.36-0.97) and reduced postoperative stroke (RR, 0.60, 95% CI, 0.39-0.91). Also, interesting trends towards reduced postoperative intra-aortic balloon pump use (RR, 0.56, 95% CI, 0.31-1.01) and myocardial infarction (RR, 0.48, 95% CI, 0.22-1.07) were observed. Baseline characteristics and postoperative complications were similar between OPBHC and off-pump CABG, but limited data are available. The risk of incomplete revascularization in OPBHC is lower than off-pump CABG (RR, 0.53, 95% CI, 0.33-0.87) but higher than conventional on-pump CABG (RR, 1.71, 95% CI, 1.23-2.39).

CONCLUSION

OPBHC is an effective technique to perform surgical revascularization in high-risk patients as preventing haemodynamic deterioration and guaranteeing adequate end-organ perfusion. OPBHC represents an alternative technique to on-pump and off-pump CABG, in those cases in which complications deriving from cardioplegic arrest or manipulation of the heart are more likely. For these reasons, OPBHC might be useful in patients with recent myocardial infarction or with left ventricular dysfunction.

Emergency surgery for left main disease: with and without cardioplegic arrest

BACKGROUND

The aims of this study were to evaluate the on-pump beating-heart technique of coronary artery bypass in patients with acute myocardial infarction and left main disease, and to retrospectively compare the early postoperative results with those of conventional on-pump arrested-heart coronary surgery.

METHODS

Eighty-five patients with acute myocardial infarction caused by left main disease, who underwent emergency surgery between January 1998 and April 2017 at Saiseikai Utsunomiya Hospital, were enrolled in this study. Of these patients, 56 were evaluated using propensity-matched analysis. The patients were divided into two groups according to the surgical procedure: group A ( n = 28) had on-pump surgery on the arrested heart, and group B ( n = 28) had on-pump surgery on the beating heart. Early postoperative results were compared between the two groups.

RESULTS

Preoperative and intraoperative characteristics showed no significant differences between the two groups. The peak creatine kinase myocardial band level was significantly lower in group B (group A 151 vs. group B 91 IU·L^-1, p = 0.01). The early mortality rate was higher in group A than group B, but the difference was not significant (group A 28.6% vs. group B 17.9%, p = 0.53).

CONCLUSIONS

There was no significant advantage based on surgical procedure between on-pump beating-heart surgery and on-pump surgery on the arrested heart. On-pump beating-heart coronary artery bypass grafting significantly reduced the peak creatine kinase myocardial band level, but there were no significant differences in the early postoperative data, including the mortality rate and left ventricular function.

On-pump beating heart versus conventional coronary artery bypass grafting: comparative study on early and long-term clinical outcomes

Background

We reviewed our experience with on-pump beating (OPB) heart coronary artery bypass grafting (CABG) to evaluate the impacts of obviating aortic cross-clamping and cardioplegic arrest on clinical outcomes compared with conventional CABG (C-CABG).

Methods

Between 2006 and 2012, elective isolated cardiopulmonary bypass (CPB)-assisted CABG was consecutively performed in 645 patients (mean patient age 63.3±9.1 years, 471 women) with 254 (39.4%) undergoing OPB-CABG and 391 (60.6%) undergoing C-CABG. The early and long-term clinical outcomes were compared between the two groups after adjusting for risk profiles through propensity score (PS) analyses.

Results

The OPB-CABG group presented significant morbidities more frequently than the C-CABG group, including severe chronic kidney disease (CKD) (P=0.026), severe chest pain (P<0.001), and poor left ventricular function (P<0.001). Early mortality occurred in 6 (2.4%) and 2 (0.5%) patients in the OPB- and C-CABG group, respectively (P=0.087). The number of distal anastomosis was comparable between the two groups (3.0±0.9 vs. 3.0±1.0, P=0.816). After PS matching, the incidence of major complications such as stroke (P>0.99) and new-onset dialysis (P=0.109) was comparable. During a median follow-up of 81.0 months (quartiles 1-3, 66.6-95.0 months), 118 patients died and the PS-matched models showed no significant between-group differences in the risk of overall death [hazard ratio (HR), 1.19; 95% confidence interval (CI), 0.72-1.95; P=0.507] and major adverse cardiac events (MACE) (HR, 1.49; 95% CI, 0.67-3.31; P=0.328).

Conclusions

The OPB strategy may be as safe and effective as the conventional strategy during CABG among patients with similar risk profiles. A prospective randomized trial is warranted to better ascertain the beneficial impact of OPB-CABG as both a viable and a durable alternative strategy to C-CABG.

Early clinical outcomes of on-pump beating-heart versus off-pump technique for surgical revascularization in patients with severe left ventricular dysfunction: the experience of a single center

Background

Limited experiences of applying an on-pump beating-heart technique for surgical revascularization in patients with severe left ventricular dysfunction have been reported. Which strategy, either off-pump coronary artery bypass grafting (CABG) or on-pump beating-heart CABG surgery, is the best strategy for surgical revascularization in patients with severe left ventricular dysfunction is still controversial. This single-center study aimed to evaluate the impacts of an on-pump beating-heart versus an off-pump technique for surgical revascularization on the early clinical outcomes in patients with a left ventricular ejection fraction (LVEF) of 35% or less to explore which technique would be more suitable for surgical revascularization in patients with severe left ventricular dysfunction.

Methods

A total of 216 consecutive patients with an echocardiographic estimated LVEF of 35% or less who underwent non-emergency, primary, isolated CABG from January 2010 to December 2014 were included in this study and were divided into either an ONBEAT group (patients who received on-pump beating-heart CABG surgery, n = 88) or an OFF group (patients who received off-pump CABG surgery, n = 128). The early clinical outcomes were investigated and compared.

Results

Patients in the ONBEAT group compared to the OFF group had a significant higher early postoperative LVEF (35.6 ± 2.9 vs. 34.8 ± 3.3%, p = 0.034) but shared a similar baseline LVEF (31.0 ± 2.8 vs. 31.0 ± 2.9%, p = 0.930). Patients in the ONBEAT group compared to the OFF group received a greater number of grafts and an increased amount of drainage during the first 24 h (3.7 ± 0.8 vs. 2.8 ± 0.6, p <0.001; 715 ± 187 ml vs. 520 ± 148 ml, p <0.001, respectively), without evidence of worse in-hospital mortality or major postoperative morbidity. Additionally, logistic regression analysis showed that surgical technique (on-pump beating-heart CABG vs. off-pump CABG) had no independent influence on in-hospital mortality or major postoperative morbidity in patients with preoperative LVEF of 35% or less.

Conclusions

The on-pump beating-heart technique may be an acceptable alternative to the off-pump technique for surgical revascularization in patients with an estimated LVEF of 35% or less.

Impact of surgeon experience on the rate of blood transfusion in off-pump coronary artery bypass

BACKGROUND/PURPOSE

Off-pump coronary artery bypass (OPCAB) reduces the rate of blood transfusion. No studies have focused on the effect of surgeon experience on the transfusion rate. We sought to assess the transfusion rate in OPCAB and to evaluate the effect of surgeon experience.

METHODS

Retrospective review of 1055 consecutive patients undergoing OPCAB between 2000 and 2012. Patients were divided into tripartites by the year of operation (2000-2004, 2005-2008, and 2009-2012). Surgeon experience was evaluated with revascularization index and conversion rate.

RESULTS

Mode of intervention was elective in 768, urgency in 185, and emergency in 102 patients (10%). Blood transfusion was associated with increased rates of hospital mortality and sternal wound/bloodstream infections. Revascularization index was 1.22 ± 0.29 per patient and increased over time, from 1.05 ± 0.21 in 2000-2004 to 1.39 ± 0.26 in 2009-2012. Conversion rate was 10% and decreased over time, from 17% in 2000-2004 to 6% in 2009-2012. The average rate of blood transfusion was 58% and decreased over time, from 74% in 2000-2004 to 41% in 2009-2012. Rate of red blood cell transfusion was 56% and decreased from 72% in 2000-2004 to 40% in 2009-2012. Rate of platelet transfusion was 21% and decreased from 25% in 2000-2004 to 15% in 2009-2012.The most significant decrease in the transfusion rate was observed in nonemergency cases.

CONCLUSION

Surgeon experience reduced the need of blood transfusion after OPCAB. Increasing surgeon experience was associated with a 33% reduction in blood transfusion rate.

A multidisciplinary approach to unplanned conversion from off-pump to on-pump beating heart coronary artery revascularization in patients with compromised left ventricular function

Aim. To comparably assess the perioperative risk factors that differentiate off-pump coronary artery bypass (OPCAB) grafting cases from those sustaining unplanned conversion to on-pump beating heart (ONCAB/BH) approach, in patients with left ventricular ejection fraction (LVEF) < 40%. Methods. Perioperative variables were retrospectively assessed in 216 patients with LVEF < 40%, who underwent myocardial revascularization with OPCAB (n = 171) or ONCAB/BH (n = 45) approach. The study endpoints were operative mortality (30-day) and morbidity assessed by length of intensive care unit stay (LOS-ICU), using 2 days as cut-off point. Results. Poor LVEF, increased EuroSCORE II, acute presentation, congestive heart failure, cerebrovascular disease, perioperative renal impairment, clinical status deterioration upon admission and during ICU stay, acute myocardial infarction, and low cardiac output syndrome supported by inotropes and/or balloon-pump counterpulsation were significantly related to ONCAB/BH group (P < 0.05). EuroSCORE II (P = 0.01) and LVEF (P = 0.03) were the most powerful discriminative predictors of intraoperative conversion to ONCAB/BH. Operative mortality was 2.9% in OPCAB and 6.6% in ONCAB/BH group (P = 0.224), while 23.4% participants in OPCAB and 42.2% in ONCAB/BH approach had a LOS-ICU > 2 days (P = 0.007). Conclusions. Patients with LVEF < 40% undergoing ONCAB/BH are subjected to more preoperative comorbidities and implicated ICU stay than their OPCAB counterparts, which influences adversely short-term morbidity, while operative mortality remains unaffected.

Blood stream infection in patients undergoing systematic off-pump coronary artery bypass: incidence, risk factors, outcome, and associated pathogens

BACKGROUND

Blood stream infection (BSI) is a major cause of mortality and morbidity for patients undergoing cardiac surgery. However, information is lacking about patients undergoing off-pump coronary artery bypass (OPCAB). The purpose of this study was to assess the incidence, risk factors, outcome and associated pathogens of BSI after OPCAB.

METHODS

One thousand ten consecutive patients undergoing OPCAB between 2001 and 2012 were included in a retrospective case-control study. A propensity-matched control was used for risk factor analysis.

RESULTS

Of the 1,010 patients, 26 patients (2.6%) had 32 episodes of BSI after surgery, which occurred at a median of 14 d after surgery. Gram-negative bacilli and gram-positive cocci were distributed equally. Methicillin-resistant Staphylococcus aureus was the pathogen identified most frequently, and the most common source of infection was a surgical site. The hospital mortality rate was 54%. By univariable analysis, diabetes mellitus, pre-operative renal impairment, pre-operative low hemoglobin, pre-operative endotracheal intubation, dialysis before or after surgery, cardiogenic shock, left ventricular ejection fraction of less than 40%, non-elective surgery, low number of distal anastomoses, atrial fibrillation after surgery, and re-operation for bleeding were significant risk factors. By multivariable analysis, the independent risk factors were left ventricular ejection fraction of less than 40%, low number of distal anastomoses, atrial fibrillation after surgery, and dialysis after surgery.

CONCLUSIONS

Blood stream infections remained a common complication after OPCAB, and the mortality was high. Gram-negative bacilli and gram-positive cocci were distributed equally. Methicillin-resistant S. aureus was the pathogen identified most frequently. Preventive tactics should target likely pathogens and high-risk patients undergoing OPCAB.

Malignant ventricular arrhythmias after off-pump coronary artery bypass

BACKGROUND/PURPOSE

Sustained ventricular tachycardia and ventricular fibrillation (VT/VF) are rare complications after coronary surgery. Off-pump coronary artery bypass (OPCAB) was developed to decrease postoperative complications. No studies to date have specifically addressed VT/VF after OPCAB. We sought to assess the incidence, risk factors, and outcome of VT/VF after OPCAB.

METHODS

The study included a retrospective review of 1010 patients undergoing OPCAB between 2000 and 2012. Data were compared between the VT/VF patients and control patients who were the first cases of OPCAB in each month during the study period and did not have VT/VF.

RESULTS

Twenty-three patients (2.3%) developed VT/VF after OPCAB. The hospital mortality rate was 17.4%. In univariate analysis, the risk factors for VT/VF were old age, rapid heart rate, prolonged corrected QT interval, severe congestive heart failure, poor left ventricular ejection fraction, large left ventricular end-diastolic diameter, chronic kidney disease, preoperative dialysis, low blood hemoglobin level, preoperative intubation, recent myocardial infarction, high European System for Cardiac Operative Risk Evaluation, urgent/emergent operation, use of intra-aortic balloon pump, conversion to on-pump beating heart, postoperative dialysis, and no use of beta-blockers after operation. Multivariate analysis identified preoperative corrected QT interval > 426 milliseconds [odds ratio (OR) = 4.501; 95% confidence interval (CI) = 1.153-17.570] and estimated glomerular filtration rate < 30 mL/minute/1.73 m(2) (OR = 4.876; 95% CI = 1.112-21.374) as independent risk factors.

CONCLUSION

Postoperative VT/VF was rare after OPCAB but was associated with high mortality. Prolonged corrected QT interval and chronic kidney disease were independent risk factors. Recognition of these risk factors, proper prevention, and early intervention may improve survival.

On-pump beating-heart versus conventional coronary artery bypass grafting for revascularization in patients with severe left ventricular dysfunction: early outcomes

BACKGROUND

We sought to evaluate the effects of on-pump beating-heart versus conventional coronary artery bypass grafting techniques requiring cardioplegic arrest in patients with coronary artery disease with left ventricular dysfunction.

METHODS

We report the early outcomes associated with survival, morbidity and improvement of left ventricular function in patients with low ejection fraction who underwent coronary artery bypass grafting between August 2009 and June 2012. Patients were separated into 2 groups: group I underwent conventional coronary artery bypass grafting and group II underwent an on-pump beating-heart technique without cardioplegic arrest.

RESULTS

In all, 131 patients underwent coronary artery bypass grafting: 66 in group I and 65 in group II. Left ventricular ejection fraction was 26.6% ± 3.5% in group I and 27.7% ± 4.7% in group II. Left ventricular end diastolic diameter was 65.6 ± 3.6 mm in group I and 64.1 ± 3.2 mm in group II. There was a significant reduction in mortality in the conventional and on-pump beating-heart groups (p < 0.001). Perioperative myocardial infarction and low cardiac output syndrome were higher in group I than group II (both p < 0.05). Improvement of left ventricular function after the surgical procedure was better in group II than group I.

CONCLUSION

The on-pump beating-heart technique is the preferred method for myocardial revascularization in patients with left ventricular dysfunction. This technique may be an acceptable alternative to the conventional technique owing to lower postoperative mortality and morbidity.

Early and mid-term outcomes of combined aortic valve replacement and coronary artery bypass grafting in elderly patients

OBJECTIVES

Although the number of elderly patients undergoing combined aortic valve replacement (AVR) and coronary artery bypass grafting (CABG) is increasing, the early and mid-term outcomes of this combined procedure remain to be determined. We sought to elucidate the early and mid-term outcomes of elderly (≥75 years) vs non-elderly (<75 years) patients who underwent combined AVR and CABG.

METHODS

Between September 2004 and September 2011, 259 patients underwent combined AVR and CABG at our institute, including 155 elderly patients (59.8%; Elderly group) with a mean age of 79.8 ± 3.6 years and 104 non-elderly patients (40.2%; Non-elderly group) with a mean age of 67.3±5.8 years. Early and mid-term outcomes were compared, and multivariate analyses were performed to determine the risk factors for morbidity and mortality. The mean follow-up times were 33.1±21.7 and 37.4±22.2 months in the Elderly and Non-elderly groups, respectively.

RESULTS

The mean number of anastomoses and the frequency of use of the internal thoracic artery were similar between the two groups. The use of a mechanical valve was less frequent in the Elderly group than in the Non-elderly group (11.6 vs 60.6%, P<0.001). The Elderly and Non-elderly groups had similar rates of operative death (1.9 vs 1.0%, P=0.651), early stroke (2.6 vs 1.0%, P=0.651), 5-year overall survival (83.1±4.8 vs 87.2±5.2%, P=0.358), 5-year freedom from cardiac death (92.3±2.7 vs 94.8±3.4%, P=0.570) and 5-year freedom from stroke (94.0±2.6 vs 99.0±1.0%, P=0.097). Cox proportional hazards analyses identified diabetes, creatinine level and EuroSCORE II, but not age, as independent predictors of overall mortality rate.

CONCLUSIONS

Early and mid-term outcomes of combined AVR and CABG were similar between elderly and non-elderly patients. Older age was not a risk factor for mortality in patients undergoing combined AVR plus CABG, and this procedure should be recommended in properly selected elderly patients.

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.

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.

Management of patients with a calcified aorta or low ejection fraction undergoing multivessel coronary revascularization

Off-pump coronary artery bypass surgery (OPCAB) provides an alternative method of surgical revascularization by allowing coronary anastomoses to be constructed without the use of cardiopulmonary bypass and without manipulation of the aorta. The presence of a calcified aorta is one of the strongest indications for OPCAB because both distal and proximal anastomoses can be performed without cannulation or clamping of the aorta. In patients with left ventricular dysfunction, OPCAB techniques allow for revascularization without the need for global myocardial ischemia associated with cardioplegic arrest.

Myocardial revascularization using on-pump beating heart among patients with left ventricular dysfunction

Objectives

On-pump beating heart technique for myocardial revascularization has been used successfully among both low and high risk patients. Its application among low ejection fraction patients is limited. The aim of our study is to evaluate this technique among patients with low ejection fraction and to compare results with off-pump bypass technique.

Methods

This retrospective study includes 137 patients with ejection fraction below 0.35 who underwent isolated coronary artery bypass surgery. 39 patients underwent myocardial revascularization using on-pump beating heart (ONCAB/BH), while 98 patients had off-pump beating heart (OPCAB). Different preoperative, operative and postoperative variables were evaluated among both groups.

Results

Patients profiles and risk factors were similar among both groups, except for the number of patients undergoing redo CABG which was significantly higher among ONCAB/BH (13% vs 3%; p = 0.025). Ejection fraction (EF) varied from 10-34%. The mean EF for patients who underwent ONCAB/BH was 28 ± 6 in comparison to 26 ± 5 for OPCAB patients (P = 0.093). Predicted risk for surgery according to EuroSCORE was similar among both groups (P = 0.443). The number of grafts performed per patient was significantly more among patients who underwent ONCAB/BH (2.2 ± 0.7 Vs 1.7 ± 0.7; P = 0.002). Completeness of revascularization was significantly greater in the ONCAB/BH patients (72% Vs 46%, P = 0.015). The incidence of hospital mortality and combined major morbidity was more among ONCAB/BH in comparison to OPCAB, but the difference was not significant. However, the incidence of blood loss, ventricular arrythmias, inotropic support, ICU, hospital stay and blood transfusion were significantly greater among patients who underwent ONCAB/BH.

Conclusions

On-pump beating heart technique can be used in myocardial revascularization among patients with left ventricular dysfunction. The technique was found to be associated with better myocardial revascularization when compared with OPCAB technique. However, the incidence of morbidity and mortality was more than OPCAB.