Shane George

Does off-pump coronary artery bypass (OPCAB) surgery improve the outcome in high-risk patients?: a comparative study of 1398 high-risk patients

OBJECTIVE Although there has been some evidence supporting the theoretical and practical advantages of off-pump coronary artery bypass (OPCAB) over the conventional coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB), it has not yet been determined which group of patients would benefit most from it. It has been advocated recently that high-risk patients could benefit most from avoidance of CPB. The aim of this retrospective study is to assess the efficacy of the OPCAB technique in multi-vessel myocardial revascularization in a large series of high-risk patients. METHODS The records of 1398 consecutive high-risk patients who underwent primary isolated CABG at Harefield Hospital between August 1996 and December 2001 were reviewed retrospectively. Patients were considered as high-risk and included in the study if they had a preoperative EuroSCORE of > or =5. Two hundred and eighty-six patients were operated on using the OPCAB technique while 1112 patients were operated on using the conventional CABG technique with CPB. The OPCAB patients were significantly older than the CPB patients (68.1+/-8.3 vs. 63.7+/-9.9 years, respectively, P<0.001). The OPCAB group included significantly more patients with poor left ventricular (LV) function (ejection fraction (EF) < or =30%) (P<0.001) and more patients with renal problems (P<0.001). RESULTS There was no significant difference in the number of grafts between the groups. The CPB patients received 2.8+/-1.2 grafts per patient while OPCAB patients received 2.8+/-0.5 grafts per patient (P=1). Twenty-one (7.3%) OPCAB patients had one or more major complications, while 158 (14.2%) CPB patients (P=0.008) developed major complications. Thirty-eight (3.4%) CPB patients developed peri-operative myocardial infarction (MI) while only two (0.7%) OPCAB patients developed peri-operative MI (P=0.024). The intensive therapy unit (ITU) stay for OPCAB patients was 29.3+/-15.4 h while for CPB patients it was 63.6+/-167.1 h (P<0.001). There were ten (3.5%) deaths in the OPCAB patients compared to 78 (7%) deaths in the CPB patients (P=0.041) within 30 days postoperatively. CONCLUSIONS This retrospective study shows that using the OPCAB technique for multi-vessel myocardial revascularization in high-risk patients significantly reduces the incidence of peri-operative MI and other major complications, ITU stay and mortality. Even though the OPCAB group included a significantly higher proportion of older patients with poor LV function (EF < or =30%) and renal problems, the beneficial effect of OPCAB was evident.

Effect of off-pump coronary artery bypass surgery on clinical, angiographic, neurocognitive, and quality of life outcomes: randomised controlled trial

Abstract Objective To compare the clinical, angiographic, neurocognitive, and quality of life outcomes of off-pump coronary artery bypass surgery with conventional coronary artery bypass grafting surgery using cardiopulmonary bypass. Design Randomised controlled clinical trial. Setting Tertiary cardiothoracic centre in Middlesex, England. Participants 168 patients (27 women) requiring primary isolated coronary artery bypass grafting surgery. Interventions Patients were randomised to conventional coronary artery bypass grafting surgery using cardiopulmonary bypass (n = 84) or off-pump coronary artery bypass surgery (n = 84), carried out by one surgeon. Angiographic examination was carried out at three months postoperatively. Neurocognitive tests were carried out at baseline and at six weeks and six months postoperatively. Main outcome measures Clinical outcome, graft patency at three months, neurocognitive function at six weeks and six months, and health related quality of life. Results Graft patency was evaluated by angiography in 151 (89.9%) patients and was similar between the cardiopulmonary bypass and off-pump groups (risk difference − 1%, 95% confidence interval − 5% to 4%), with the off-pump group considered the treatment group. Patients in the off-pump group required fewer blood transfusions (1.7 units v 1.0 unit, P = 0.02), shorter duration of mechanical ventilation (7.7 hours v 3.9 hours, P = 0.03), and shorter hospital stay (10.8 days v 8.9 days). Scores for neurocognitive function showed a significant difference in three memory subtests at six weeks and two memory subtests at six months in favour of the off-pump group. Conclusions Patients who underwent off-pump coronary artery bypass surgery showed similar patency of grafts, better clinical outcome, shorter hospital stay, and better neurocognitive function than patients who underwent conventional coronary artery bypass grafting surgery using cardiopulmonary bypass.

Predictors of poor mid-term health related quality of life after primary isolated coronary artery bypass grafting surgery

Objective: To assess the determinants of poor mid-term health related quality of life (HRQoL) at one year after primary isolated coronary artery bypass grafting (CABG). Methods: 463 patients who underwent primary isolated CABG for multivessel disease and came for their annual follow up at the outpatient clinic during one year at Harefield Hospital, Middlesex, were approached to participate in the present study. Prospective clinical data were collected as part of the clinical care of the patients and were retrospectively analysed when the patients consented to participate in the study at their outpatient visit. After their consent they were given three HRQoL assessment questionnaires. Scores, together with clinical data, were analysed by both univariate and multivariate analyses with regard to poor HRQoL outcome. Results: 437 (94.4%) patients consented to participate in the study and filled in the HRQoL questionnaires. Ten variables were identified in the univariate analysis as potential predictors of poor scores of the physical element of HRQoL; however, only three variables—gastrointestinal problems, congestive heart failure, and type D personality trait—predicted poor physical scores independently. Eleven variables were identified in the univariate analysis as potential predictors of poor scores of the mental element of HRQoL; however, only three variables—peripheral vascular disease, infective complications, and type D personality trait—predicted poor physical scores independently. Conclusion: Preoperative gastrointestinal problems, preoperative congestive heart failure, and type D personality trait were independent predictors of the poor physical component of HRQoL. Peripheral vascular disease, infective complications, and type D personality trait were independent predictors of the poor mental component of HRQoL. Interestingly, patients with type D personality were more than twice as likely to have poor physical HRQoL and more than five times as likely to have poor mental HRQoL.

Mitral annulus distortion during beating heart surgery: a potential cause for hemodynamic disturbance—a three-dimensional echocardiography reconstruction study

BACKGROUND Positioning for access to the coronary arteries leads to hemodynamic instability during off-pump cardiac surgery. External changes have been well described, but a description of the intracardiac structures in humans has not been described. METHODS With multiplane intraoperative echocardiography, the mitral annulus at end diastole was reconstructed in the different positions and correlated with hemodynamic changes in the right heart and left atrium. RESULTS Significant distortion of the mitral annulus with enlargement of the left atrium and pulmonary veins was demonstrated, which correlated with high left atrial pressures. CONCLUSIONS Mitral valve distortion can significantly contribute to hemodynamic instability during positioning for off-pump cardiac surgery.

Extracorporeal membrane oxygenation in burn and smoke inhalation injury

A systematic review and meta-analysis was conducted to assess the level of evidence for the use of extracorporeal membrane oxygenation (ECMO) in hypoxemic respiratory failure resulting from burn and smoke inhalation injury. We searched any article published before March 01, 2012. Available studies published in any language were included. Five authors rated each article and assessed the methodological quality of studies using the recommendation of the Oxford Centre for Evidence Based Medicine (OCEBM). Our search yielded 66 total citations but only 29 met the inclusion criteria of burn and/or smoke inhalation injury. There are no available systematic reviews/meta-analyses published that met our inclusion criteria. Only a small number of clinical trials, all with a limited number of patients, were available. The overall data suggests that there is no improvement in survival for burn patients suffering acute hypoxemic respiratory failure, with the use of ECMO. ECMO run times of less than 200 h correlate with higher survival compared to 200 h or more. Scald burns show a tendency of higher survival than flame burns. In conclusion, the presently available literature is based on insufficient patient numbers; the data obtained and level of evidence generated are limited. The role of ECMO in burn and smoke inhalation injury is therefore unclear. However, ECMO technology and expertise have improved over the last decades. Further research on ECMO in burn and smoke inhalation injury is warranted.

Is the use of cardiopulmonary bypass for multivessel coronary artery bypass surgery an independent predictor of operative mortality in patients with ischemic left ventricular dysfunction

BACKGROUND l Coronary artery bypass grafting for patients with ischemic left ventricular dysfunction (ILVD) remains superior to medical therapy in terms of long-term survival. Recently, off-pump coronary artery bypass surgery has been shown to be very promising in achieving functional improvements with favorable operative mortality in this challenging group of patients. The aim of this study was to assess the risk factors responsible for operative mortality in this group of patients. METHODS The records of 305 consecutive ILVD patients, who underwent primary isolated coronary artery bypass grafting for multivessel disease at The National Heart and Lung Institute, Imperial College, University of London, between January 1999 and January 2002, were reviewed retrospectively. Patients were considered to have ILVD if they had a left ventricular ejection fraction of 0.30 or less on preoperative coronary angiography. One hundred six patients were operated on using the off-pump coronary artery bypass surgery technique, and 199 patients were operated on using the conventional coronary artery bypass grafting technique with cardiopulmonary bypass. RESU;TS: Seven (6.6%) patients died in the off-pump coronary artery bypass surgery group, whereas 28 (14.1%) patients died in the cardiopulmonary bypass group (p = 0.05). Univariate analysis of all the preoperative characteristics was performed to identify the potential predictors of mortality in the whole group of ILVD patients. Potential predictors of mortality included symptom status (stable/unstable), chronic obstructive airway disease, dyspnea grade III and IV on the New York Heart Association classification, intravenous nitrates, preoperative use of intraaortic balloon pump, ventricular tachycardia or ventricular fibrillation, body surface area less than 2, and cardiopulmonary bypass. Only ventricular tachycardia or ventricular fibrillation was proved to act as an independent predictor of operative mortality in this group of ILVD patients, with an odds ratio of 29.6 (95% confidence interval, 8.9 to 98). CONCLUSIONS This study showed that using cardiopulmonary bypass for multivessel coronary artery bypass grafting in patients with ILVD was not proved to act as an independent predictor of operative mortality.

Conversion to off-pump coronary bypass without increased morbidity or change in practice

BACKGROUND This article examines the feasibility of complete conversion from conventional coronary artery operation to routine off-pump coronary bypass operation. METHODS Data on our first 285 off-pump procedures using the Octopus system (Medtronic Inc, Minneapolis, MN) represent our learning curve. This is a complete experience in coronary bypass surgery over 16 months. RESULTS The cohort was nonselected. All patients had at least two-vessel disease. Eight hundred seven grafts were performed (mean, 2.8 per patient) of which 647 grafts (84%) were arterial (mean, 2.3 per patient). One hundred seventy nine patients (63%) underwent total arterial revascularization. Eight patients required cardiopulmonary bypass; all other operations were completed off-pump. Complications were: mortality, 3 patients (1.5%); renal failure, 24 patients (8%); stroke, 2 patients (< 1%); and atrial fibrillation, 60 patients (21%). The morbidity data and frequency of arterial grafting did not differ from that of 355 patients who underwent coronary bypass operations in a preceding 18-month period. CONCLUSIONS Complete shift from routine use of cardiopulmonary bypass to nonselective off-pump coronary bypass operation is possible with a low conversion rate and without an apparent increase in morbidity or change in technique. Whereas short-term safety and efficacy seem certain, studies of long-term outcome are necessary before the eventual role of off-pump coronary bypass in myocardial revascularization can be defined.

Comparison of clinical and economic outcomes of two antibiotic prophylaxis regimens for sternal wound infection in high-risk patients following coronary artery bypass grafting surgery: a prospective randomised double-blind controlled trial

Objective: Prospective studies show a 10% incidence of sternal wound infection (SWI) after 90 days of follow-up, compared with infection rates of 5% reported by the National Nosocomial Infections Surveillance System after only 30 days of follow-up. This incidence increases 2–3 times in high-risk patients. Design: Prospective randomised double-blind controlled clinical trial. Setting: Cardiothoracic centre, UK. Patients: Patients were eligible if they were undergoing median sternotomy for primary isolated coronary artery bypass grafting, with at least one internal thoracic artery used for coronary grafting and having one or more of the following three risk factors: (1) obesity, defined as body mass index 30 kg/m2; (2) diabetes mellitus; or (3) bilateral internal thoracic artery grafts (ie, the use of the other internal thoracic artery). Interventions: The study group received a single dose of gentamicin 2 mg/kg, rifampicin 600 mg and vancomycin 15 mg/kg, with three further doses of 7.5 mg/kg at 12-hour intervals. The control group received cefuroxime 1.5 g at induction and three further doses of 750 mg at 8-hour intervals. Main outcome measures: The primary end point was the incidence of SWI at 90 days. The secondary end point was the antibiotic and hospital costs. Results: During the study period, 486 patients underwent isolated coronary artery bypass grafting with a 30-day SWI of 7.6%. 186 high-risk patients were recruited and analysed: 87 in the study group and 99 in the control group. 90-day SWI was significantly reduced in 8 patients in the study group (9.2%; 95% CI 3.5% to 15.3%) compared with 25 patients in the control group (25.2%; 95% CI 19.5% to 39.4%; p = 0.004). The study group had a significantly lower cost of antibiotics (21.2% reduction—US

Economic Evaluation of Coronary Artery Bypass Grafting Surgery With and Without Cardiopulmonary Bypass: Cost-Effectiveness and Quality-Adjusted Life Years in a Randomized Controlled Trial

96/patient; p<0.001), and a significantly lower hospital cost (20.4% reduction in cost—US

The clinical outcome and quality of life following minimally invasive direct coronary artery bypass surgery.

3800/patient; p = 0.04). Conclusions: Longer and broader-spectrum antibiotic prophylaxis significantly reduces the incidence of SWI in high-risk patients, with a significant economic benefit in costs of antibiotics as well as hospital costs.