Atrial fibrillation after coronary artery bypass grafting without cardiopulmonary bypass

Postoperative Atrial Fibrillation Following Off-Pump Coronary Artery Bypass Graft Surgery: Elderly Versus Young Patients

Background Atrial fibrillation (AF) is one of the common rhythm disturbances that occur after coronary artery bypass graft (CABG) surgery. Postoperative atrial fibrillation (POAF) can lead to thromboembolic events, hemodynamic instability, and prolonged hospital stay, affecting morbidity and influencing short and long-term outcomes after CABG. Methodology This prospective comparative study was conducted between May 2018 and April 2020. This study aimed to compare the prevalence of POAF following off-pump coronary artery bypass graft surgery (OPCAB) between elderly and young patients. Additionally, we aimed to determine the risk factors associated with POAF following OPCAB in the elderly compared to young patients. Patients aged ≥65 years were considered elderly, and those aged <65 years were considered young. A total of 120 patients (60 in the elderly group and 60 in the young group) were included in this study and evaluated to correlate the preoperative and intraoperative risk factors with postoperative outcomes during the hospital stay. Results The prevalence of POAF following OPCAB in the elderly was significantly higher compared to young patients (48.3% vs. 20%,p = 0.002). The elderly group also had a significantly longer intensive care unit stay (p = 0.001) and hospital stay (p = 0.001). In an unadjusted logistic regression model, age (odds ratio (OR) = 3.74, 95% confidence interval (CI) = 1.66-8.41, p = 0.001), preoperative plasma B-type natriuretic peptide (OR = 1.01, 95% CI = 1.00-1.01, p = 0.001), and left atrial diameter (OR = 1.10, 95% CI = 1.03-1.17, p = 0.001) were significantly associated with POAF. However, in an adjusted logistic regression model, age was found to be an independent predictor (OR = 1.31, 95% CI = 1.14-1.52, p < 0.0001) of POAF following OPCAB. Although stroke developed in the elderly (p >0.05), no mortality was observed postoperatively. Conclusions The prevalence of POAF following OPCAB in the elderly is higher than in young patients. Advancing age is an independent predictor of POAF following OPCAB.

Prevalence of Postoperative Atrial Fibrillation Following Off-Pump Coronary Artery Bypass Graft Surgery in Elderly Patients

Background Atrial fibrillation (AF) is one of the frequent complications following coronary artery bypass surgery. Postoperative atrial fibrillation (POAF) can lead to thromboembolic events and prolong hospital stays. We aimed to determine the prevalence of POAF following off-pump coronary artery bypass surgery (OPCAB) in the elderly population.  Materials and Methods  This cross-sectional study was carried out between May 2018 to April 2020. Elderly patients (age ≥65 years) admitted for isolated elective OPCAB were eligible for the study. A total of 60 elderly patients were evaluated based on the preoperative and intraoperative risk factors and postoperative outcomes during the hospital stay. Results The mean age was 67.83±4.06 years, and the prevalence of POAF in elderly adults was 48.3%. The mean number of grafts was 3.20±0.73, and ICU stays at 3.43±1.61 days. The mean duration of the hospital stays was 10.03±2.12 days. Although stroke developed in 1.7% of post-CABG patients, no mortality was observed postoperatively. Conclusion  POAF is one of the commonly encountered complications following OPCAB. Though OPCAB is a superior revascularization procedure, preoperative planning and attention are especially needed in the elderly to reduce the prevalence of POAF.

Mini-extracorporeal circulation surgery produces less inflammation than off-pump coronary surgery

OBJECTIVES

Both off-pump coronary artery bypass grafting surgery (OPCABG) and mini-extracorporeal circulation (MECC) have been associated with lower morbidity and mortality and less inflammation than conventional cardiopulmonary bypass. However, studies comparing the 2 techniques are scarce and the results are controversial. We compared the clinical outcomes and inflammatory response of low-risk patients undergoing coronary bypass grafting with MECC versus OPCABG.

METHODS

We conducted a prospective, randomized study in patients undergoing coronary heart surgery. Two hundred and thirty consecutive low-risk patients were randomly assigned to either receive OPCABG (n = 117) or MECC (n = 113). Clinical outcomes and postoperative biochemical results were analysed in both groups. We also analysed 19 circulating inflammatory markers in a subgroup of 40 patients at 4 perioperative time points. The area under the curve for each marker was calculated to monitor differences in the inflammatory response.

RESULTS

No significant differences were found between groups regarding perioperative clinical complications and no deaths occurred during the trial. Plasma levels in 9 of the 19 inflammatory markers were undetectable or showed no temporal variation, 3 were higher in the MECC group [interleukin (IL)-10, macrophage inflammatory protein-1β and epidermal growth factor] and 7 were higher in the OPCABG group (growth regulator oncogene, IL-6, IL-8, soluble CD40 ligand, monocyte chemoattractant protein-1, monocyte chemoattractant protein-3 and tumour necrosis factor-α). Differences in 2 proinflammatory cytokines, IL-6 and monocyte chemoattractant protein 1, between the 2 surgical procedures were statistically significant.

CONCLUSIONS

No clinical differences were observed between in low-risk patients undergoing MECC or OPCABG surgery, but OPCABG was associated with an increased release of proinflammatory cytokines compared with MECC. Studies in larger cohorts and in patients at higher risk are needed to confirm these findings.

CLINICAL TRIAL REGISTRATION NUMBER

NCT02118025.

Importância do Desenvolvimento de Fibrilação Atrial no Pós-Operatório em Cirurgia Cardíaca: Desfechos Intra-Hospitalares em Centro Terciário de Cardiologia Catarinense

Objetivo: Determinar a incidência de fibrilação atrial no pós-operatório (FAPO) de cirurgia cardíaca, seu impacto sobre a morbimortalidade e o tempo de internação hospitalar em um centro terciário de cardiologia do estado de Santa Catarina, Brasil. Métodos: Estudo de coorte com 134 pacientes adultos submetidos à cirurgia cardíaca. Resultados: A incidência foi de 32,8%. Após análise multivariada, os pacientes que não receberam betabloqueador estiveram associados à FAPO com razão de chances risco relativo (RR) 10,73 (p < 0,001). A maior taxa de eventos cardiovasculares (acidente vascular cerebral, mortalidade e síndrome coronariana aguda) foi de 25% no grupo FAPO vs. 10% (RR 3,21; p = 0,035) o que, consequentemente, gerou tempo de internação maior nesses pacientes (19,1 vs. 12,5; p = 0,01). Conclusão: A incidência de FAPO foi elevada, ocasionou significativo aumento de morbimortalidade e tempo de internação hospitalar e consolidou o papel da terapia betabloqueadora na sua prevenção, podendo servir como base a futuras políticas de prevenção dessa intercorrência.

Importance of Postoperative Atrial Fibrillation Development in Heart Surgery: Intra-Hospital Outcomes in Santa Catarina Tertiary Cardiology Center

Objective: To determine the incidence of postoperative atrial fibrillation (PAF) of cardiac surgery, its impact on morbimortality and duration of hospital stay in a tertiary cardiology center of the state of Santa Catarina, Brazil. Methods: Cohort study with 134 adult patients submitted to cardiac surgery. Results: the incidence was 32.8%. After multivariate analysis, patients who did not receive beta-blockers were associated with PAF with a relative risk odds ratio (RR) 10.73 (p <0.001). The highest rate of cardiovascular events (cerebrovascular accident, mortality, and acute coronary syndrome) was 25% in the PAF group. 10% (RR 3.21; p = 0.035) which, consequently, generated longer hospitalization time in these patients (19.1 vs. 12.5; p = 0.01). Conclusion: the incidence of PAF was high, caused a significant increase in morbimortality and duration of hospital stay, and consolidated the role of beta-blocker therapy in its prevention, and may serve as a basis for future prevention policies.

Costs, Clinical Outcomes, and Health-Related Quality of Life of Off-Pump vs. On-Pump Coronary Bypass Surgery

BACKGROUND

Off-pump coronary bypass surgery avoids the potential complications of cardiopulmonary bypass. However, its acceptance depends on medical and economic outcome. The aim of this prospective non-randomised study was to compare functional and economic outcome of off-pump and on-pump surgery at 1-year follow-up.

METHODS

102 patients (pts) treated with either off-pump (60pts) or on-pump surgery (42pts) were studied. Pts with left ventricular dysfunction, recent myocardial infarction (<1 month), renal impairment, valve surgery, previous stroke or coagulopathy were excluded. Variable and fixed costs were obtained for each treatment group during operative and postoperative care. In-hospital endpoints included all-cause mortality and complications (defined as excessive bleeding [>6 units blood transfusion], peri-operative myocardial infarction, atrial fibrillation, stroke, and infection). All cause mortality; cost-effectiveness and quality of life were assessed 1 year after surgery.

RESULTS

The in-hospital mortality was similar in the two treatment groups. Off-pump group had significantly fewer postoperative complication rate (off-pump 41% vs. on-pump 72%, p=0.001). The mean in-hospital cost was lower for off-pump surgery (off-pump 6.515+/-926 euro vs. on-pump 9.872+/-1.299 euro, p<0.0001) as well as the mean length of hospital stay (off-pump 4.93+/-0.93 days vs. on-pump 6.58+/-1.04 days, p<0.0001). At 1 year, all cause mortality, quality of life indices, return to work rate and treatment satisfaction was similar in both groups.

CONCLUSION

Off-pump myocardial revascularization maintains the advantages of conventional surgery in terms of survival and freedom from cardiac events while reducing the in-hospital cost.

Predictors of atrial fibrillation following coronary artery bypass grafting

Background:

Atrial fibrillation (AF) is a frequent and serious complication of coronary artery bypass graft (CABG) surgery.

Methods:

We undertook a retrospective review of the records of patients undergoing CABG at Imam Ali Hospital between February 1, 2003 and February 1, 2006. The patients were divided in two groups, ie, Group A (AF) and Group B (no AF). The association between the occurrence of AF following CABG and other variables was compared with respect to continuous or categorical variables by t-test and χ²-test.

Results:

Multivariate logistic regression analysis of potentially predictive factors in univariate analysis showed that opium use, type of operation, and crossclamp time were predictors of AF following CABG.

Conclusion:

This study identifies some new predictors of postoperative AF, control of which could lead to a lower incidence of AF and reduced morbidity, mortality, and resource utilization for patients undergoing cardiac surgery.

Coronary artery bypass grafting without full sternotomy

Coronary artery bypass grafting is performed without full sternotomy in selected patients because it is less invasive. Left internal thoracic artery-left anterior descending artery bypass (LITA-LAD bypass) via a small left anterior thoracotomy is a well established procedure, which achieves good graft patency with low mortality and morbidity rates. Multiple revascularization is possible with a limited lateral thoracotomy or L-figure approach. Axillary-coronary bypass and right gastroepiploic artery-right coronary artery bypass (RGEA-RCA bypass) are alternative methods, especially for redo surgery, in selected patients.

Predicting the risk of atrial fibrillation after coronary artery bypass surgery

Atrial fibrillation (AF) is the most common arrhythmia, with an incidence of 17-33%, after coronary artery bypass grafting (CABG) and it increases the cost of operative treatment. beta-Blocker therapy reduces markedly the incidence of postoperative AF. The more effective preventive methods, e.g. amiodarone therapy or atrial pacing, are not cost-effective for all the patients. Thus, identification of patients at high risk of AF after CABG would be helpful. This review summarizes the predictors of postoperative AF and the current methods for risk stratification. In summary, identification of the patients at high risk of postoperative AF remains a challenge. The clinical usefulness of most of the conventional factors, e.g. age or history of AF, is low. Even attempts to build logistic regression models based on the pre- and intraoperative variables have failed to provide powerful predictors for postoperative AF after CABG. From the new predictors, the P-wave duration in signal-averaged ECG looks promising. Sensitivity and negative predictive value are high, positive predictive value remains low, which limits its usefulness. Contrary, even detailed analysis of standard 12-lead ECG or measure of heart rate variability has failed to provide useful information for risk stratification. A new method for risk stratification has been developed in our centre. The diagnostic accuracy of high-rate atrial pacing seems to be sufficient to identify a group of patients to whom prophylactic treatment could be proactively targeted. Further experience is, however, warranted to verify significance of this method in everyday clinical practice.

Prevention of atrial fibrillation after cardiac surgery

Atrial fibrillation is the most common arrhythmia occurring after heart surgery. Its prevalence after coronary artery bypass surgery is 17-33%. Atrial fibrillation requires additional treatment, lengthens hospitalization and increases the overall expenses of cardiac surgery. Atrial fibrillation can cause hemodynamic problems, predispose to congestive heart failure and increase the risk of stroke. Beta-blockers have been shown to effectively prevent atrial fibrillation, and beta-blockers should be a part of the medication of every patient undergoing cardiac surgery, if there are no contraindications. Amiodarone therapy can also be considered for especially high-risk patients.

Atrial fibrillation after off-pump coronary artery surgery: a prospective, matched study

The effect of cardiopulmonary bypass and myocardial ischaemia on the occurrence of atrial fibrillation (AF) after coronary artery bypass graft (CABG) was studied in 136 patients undergoing off-pump CABG who were matched for age and number of distal anastomoses with 136 patients undergoing on-pump CABG. Possible risk factors for post-operative new-onset AF were recorded. AF occurred in 64 (24%) of the 267 patients for whom data could be analysed. AF occurred in 29 patients (22%) in the off-pump group versus 35 (26%) in the on-pump group, but this difference was not statistically significant. On univariate analysis, age and length of hospital stay were significant risk factors for the occurrence of AF. In a multivariate analysis that included operative technique, age was found to be the only significant risk factor. In conclusion, the occurrence of AF after CABG does not depend on the type of operation.

Does totally endoscopic access for off-pump cardiac surgery influence the incidence of postoperative atrial fibrillation in coronary artery bypass grafting? A preliminary report

BACKGROUND

The occurrence rate of atrial fibrillation (AF) after coronary artery bypass grafting, quoted in the literature, is wide ranging from 5% to over 40%. It is speculated that, off-pump coronary artery bypass grafting (OPCAB) and also minimally invasive cardiac surgery reduces the incidence of postoperative AF due to reduced trauma, ischemia, and inflammation. Current data, however, do not clearly answer the question, whether the incidence of postoperative AF is reduced in using minimally invasive techniques, ideally resulting in the combination of both small access and off-pump surgery. The aim of this study was to evaluate the incidence of postoperative AF in patients undergoing totally endoscopic off-pump coronary artery bypass grafting (TECAB).

METHODS

A retrospective analysis of 72 patients undergoing myocardial revascularization was performed. Early postoperative incidence of AF was compared between three groups of patients: 24 after conventional coronary artery bypass grafting (CABG), 24 after OPCAB, and 24 after totally endoscopic off-pump CABG. Clinical profile of the patients, including factors having potential influence on postoperative AF was matched for groups.

RESULTS

Postoperative AF occurred in 25% of the patients in the CABG group, in 16% of the patients in the OPCAB group, and in 16% of the patients in the TECAB group. This difference has no statistical significance. Risk factors and incidence of postoperative complications were comparable in all groups excepting the number of distal anastomoses. There was a statistical significance between CABG group and TECAB group.

CONCLUSION

Avoiding cardiopulmonary bypass and minimizing surgical trauma did not reduce the incidence of postoperative AF in this patient collective. It remains an attractive hypothesis that postoperative AF is reduced by off-pump myocardial revascularisation and minimizing surgical trauma but more robust data are required.

Predictors of Early Postoperative Atrial Fibrillation after Off-Pump Myocardial Revascularization

Objective

We determined the incidence and the predisposing factors of atrial fibrillation (AF) after aorta nontouch coronary artery bypass grafting without extracorporeal circulation.

Methods

From February 2001 to November 2005, 1359 patients (1159 men, 85.3%) of mean (±SD) age 64.8 (±9.8) years, who underwent off-pump coronary artery bypass grafting (OP-CAB), were prospectively enrolled. Demographics, perioperative data, and comorbidities were recorded in all patients. A 24-hour rhythm monitoring was performed in all patients until hospital discharge.

Results

Among 1359 patients, 273 (20.1%) had development of atrial fibrillation in the early postoperative period. Patients with AF had higher mean (±SD) age, 68.3 (±8.8) years, compared with control subjects [63.9 (± 9.9)] (P ≤ 0.0005). Univariate analysis showed that apart from age, history of arterial hypertension (P ≤ 0.02), chronic obstructive pulmonary disease (P ≤ 0.02), and the use of bilateral internal mammary arteries (P≤< 0.01) were predisposing factors for the development of AF. Logistic regression analysis showed that age, history of arterial hypertension, and the use of bilateral internal mammary arteries were predisposing factors for early postoperative AF after OP-CAB.

Conclusions

Atrial fibrillation occurred in approximately 20% of patients undergoing OP-CAB, mainly in older patients with arterial hypertension who received bilateral internal mammary artery grafts.

Atrial arrhythmias after cardiac surgery in patients with diabetes mellitus

BACKGROUND

Postoperative atrial fibrillation (AF) is a common complication of cardiac surgery and has been associated with increased incidence of other complications and increased hospital length of stay (LOS). Prevention of AF is a reasonable clinical goal, and, consequently, many randomized trials have evaluated the effectiveness of pharmacological and non-pharmacological interventions for prevention of AF. To better understand the role of various prophylactic therapies against postoperative AF, a systematic review of evidence from randomized trials was performed.

METHODS

MEDLINE search of English-language reports published between 1966 and July 2005 and a search of references of relevant papers were conducted. Clinical studies on AF after cardiac surgery were selected for this analysis. Relevant clinical information was extracted from selected articles.

RESULTS

Postoperative AF is associated with increased morbidity and mortality and longer, more expensive hospital stays. Prophylactic use of beta-adrenergic blockers reduces the incidence of postoperative AF and should be administered before and after cardiac surgery to all patients without contraindication. Prophylactic amiodarone and atrial overdrive pacing should be considered in patients at high risk for postoperative AF (for example, patients with previous AF or mitral valve surgery). For patients who develop AF after cardiac surgery, a strategy of rhythm management or rate management should be selected. For patients who are hemodynamically unstable or highly symptomatic or who have a contraindication to anticoagulation, rhythm management with electrical cardioversion, amiodarone, or both is preferred. Treatment of the remaining patients should focus on rate control because most will spontaneously revert to sinus rhythm within 6 weeks after discharge. All patients with AF persisting for more than 24 to 48 hours and without contraindication should receive anticoagulation.

CONCLUSIONS

AF frequently complicates cardiac surgery. Many cases can be prevented with appropriate prophylactic therapy. A strategy of rhythm management for symptomatic patients and rate management for all other patients usually results in reversion to sinus rhythm within 6 weeks of discharge.

[Off-pump coronary artery bypass: analysis of 1080 patients]

A consecutive cohort including 1080 patients undergoing "off-pump" myocardial revascularization was reviewed. An average of 2.22 bypass/patients was performed. The death-rate during the first 30 days after surgery was 0.65%. Four cases needed cross-over to on-pump. The postoperative events were: need of inotropic drugs (2.7%), atrial fibrillation (12.4%), myocardial infarction (6.6%). The extubation was performed before the first postoperative 24 h in 91.9% of cases. The majority of patients was discharged from hospital before 8 days after surgery. Off pump coronary artery bypass surgery exhibit good results for most of the patients even if they present multiple vessel disease and high operating risk.

Inflammation of atrium after cardiac surgery is associated with inhomogeneity of atrial conduction and atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is common after cardiac surgery. Abnormal conduction is an important substrate for AF. We hypothesized that atrial inflammation alters atrial conduction properties.

METHODS AND RESULTS

Normal mongrel canines (n=24) were divided into 4 groups consisting of anesthesia alone (control group); pericardiotomy (pericardiotomy group); lateral right atriotomy (atriotomy group); and lateral right atriotomy with antiinflammatory therapy (methylprednisolone 2 mg/kg per day) (antiinflammatory group). Right atrial activation was examined 3 days after surgery. Inhomogeneity of conduction was quantified by the variation of maximum local activation phase difference. To initiate AF, burst pacing was performed. Myeloperoxidase activity and neutrophil cell infiltration in the atrial myocardium were measured to quantify the degree of inflammation. The inhomogeneity of atrial conduction of the atriotomy and pericardiotomy groups was higher than that of the control group (2.02+/-0.10, 1.51+/-0.03 versus 0.96+/-0.08, respectively; P<0.005). Antiinflammatory therapy decreased the inhomogeneity of atrial conduction after atriotomy (1.16+/-0.10; P<0.001). AF duration was longer in the atriotomy and pericardiotomy groups than in the control and antiinflammatory groups (P=0.012). There also were significant differences in myeloperoxidase activity between the atriotomy and pericardiotomy groups and the control group (0.72+/-0.09, 0.41+/-0.08 versus 0.18+/-0.03 DeltaOD/min per milligram protein, respectively; P<0.001). Myeloperoxidase activity of the antiinflammatory group was lower than that of the atriotomy group (0.17+/-0.02; P<0.001). Inhomogeneity of conduction correlated with myeloperoxidase activity (r=0.851, P<0.001).

CONCLUSIONS

The degree of atrial inflammation was associated with a proportional increase in the inhomogeneity of atrial conduction and AF duration. This may be a factor in the pathogenesis of early postoperative AF. Antiinflammatory therapy has the potential to decrease the incidence of AF after cardiac surgery.

Off-pump coronary artery bypass graft surgery: the incidence of postoperative atrial fibrillation

Atrial fibrillation (AF) occurs in one quarter to one third of patients after coronary artery bypass graft surgery (CABG). Conventional CABG uses cardiopulmonary bypass, a process that is itself associated with a systemic vascular inflammatory response that contributes to postoperative morbidity. The avoidance of cardiopulmonary bypass is associated with a significant reduction in the inflammatory response and in the release of markers of myocardial necrosis when compared with conventional CABG. There is speculation that off-pump CABG may reduce the incidence of postoperative AF through reduced trauma, ischaemia, and inflammation. Current data, however, do not emphatically answer the question of whether the incidence of post-CABG AF is reduced by off-pump surgery. The evidence from both observational and randomised studies is conflicting and many studies have weaknesses in design, conduct, or interpretation. It remains an attractive hypothesis that postoperative AF is reduced by off-pump CABG but more robust data are required.

Ibutilide versus amiodarone in atrial fibrillation: a double-blinded, randomized study

OBJECTIVE

Ibutilide, a class III antiarrhythmic drug, has been shown to convert atrial fibrillation to sinus rhythm more rapidly than procainamide or sotalol. Our objective was to compare the efficacy and safety of ibutilide and amiodarone in patients after cardiac surgery.

DESIGN

Prospective, randomized, double-blinded study.

SETTING

Intensive care unit of a university hospital.

PATIENTS

Forty adults with an onset of atrial fibrillation within 3 hrs after admission.

INTERVENTIONS

Before the administration of antiarrhythmic drugs, a 24-hr Holter electrocardiograph was attached. Patients in the ibutilide group received ibutilide 0.008 mg/kg body weight over 10 mins; treatment was repeated if atrial fibrillation or flutter persisted. If sinus rhythm was not achieved within 4 hrs, amiodarone 5 mg/kg was administered over 30 mins, followed by amiodarone 15 mg/kg over 24 hrs. Patients in the amiodarone group received amiodarone 5 mg/kg over 30 mins, followed by amiodarone 15 mg/kg over 24 hrs if atrial fibrillation or flutter continued.

MEASUREMENTS AND MAIN RESULTS

Within the first 4 hrs, atrial fibrillation was converted in nine of 20 patients (45%) in group ibutilide and in ten of 20 patients (50%) in group amiodarone (not significant). Mean time for conversion overall was 385 mins in group ibutilide and 495 mins in group amiodarone (not significant). In group amiodarone, the protocol was discontinued in two patients because of severe arterial hypotension. Atrial fibrillation recurred in 11 of 20 patients (55%) in group ibutilide and in seven of 20 patients (35%) in group amiodarone (not significant). Ventricular arrhythmia did not occur during the first 24 hrs of the protocol.

CONCLUSIONS

Ibutilide has no significant advantage over amiodarone for the conversion of atrial fibrillation to sinus rhythm in either time to conversion or conversion overall, but severe hypotension was not seen with ibutilide.

Current trends and technique in OPCAB surgery

BACKGROUND AND AIM OF THE STUDY

Aging of the population, increased surgical risk, and technical improvement have contributed to the recent revival of off pump coronary artery bypass surgery (OPCAB). We present our experience with the systematic use of this technique.

METHODS

Between September 1996 and June 2000, 500 OPCAB procedures were performed at the Montreal Heart Institute (95% of all procedures during time frame, single surgeon). Contraindications were unstable hemodynamics, intramyocardial left anterior descending artery, and reoperation with extensive adhesions. Stabilization was achieved with pericardial sutures and mechanical compression. Surgical strategy was to first bypass the culprit lesion. Anesthetic management consisted of adequate fluid loading and minimal use of alpha-agonist. This cohort was compared to a contemporary cohort of 1,444 patients operated with cardiopulmonary bypass (CPB).

RESULTS

Demographics and risk factors were comparable for all. OPCAB patients received more grafts (3.1 +/- 0.9 vs 2.9 +/- 0.7, p = 0.006), conversion rate was low (0.4%), and complete revascularization was achieved in 93%. Operative mortality and perioperative myocardial infarction were comparable in both groups. Transfusion need, CK-MB count, postoperative use of intra-aortic balloon pump, and creatinine increase were less significant in OPCAB. Postoperative hemorrhage, atrial fibrillation, prevalence of cerebrovascular accident, and hospital stay were comparable for both groups. These results are comparable to those currently reported in the literature.

CONCLUSION

OPCAB surgery in the current era has established its safety and short-term efficacy although long-term clinical results are still warranted. Considering the changing pattern in surgical practice, OPCAB surgery should remain a therapeutic option in modern cardiac surgery.

[Off-pump beating heart coronary artery bypass. Technical points of view and surgical results]

A consecutive series of 746 patients undergoing heart beating myocardial revascularization was reviewed. An average of 2.30 grafts/patients was performed. The rate of mortality in the first 30 postoperative days was 0.28%. Two cases had to be terminated on-pump. We used the inotropic drugs in 0.6% of cases. The postoperative events were: atrial fibrillation (12.6%), myocardial infarction (0.3%). The rate of transfusion was 7.4%. The extubation was performed in the first 24 h postoperatively in 94.7% of cases. The majority of patients (91.3%) left the hospital in the first 8 d postoperatively. Off pump coronary artery bypass grafting gives good result for the most of the patients even for those with multiple vessel disease and high operating risk.

Off-pump coronary artery bypass with complete avoidance of aortic manipulation

BACKGROUND

Off-pump coronary artery bypass (OPCAB) with complete avoidance of aortic manipulation may further reduce perioperative morbidity in addition to the benefits achieved by avoiding cardiopulmonary bypass and cardioplegic arrest.

METHODS

We prospectively analyzed 222 consecutive patients with multivessel disease who underwent OPCAB without aortic manipulation (group I), and compared them with 123 consecutive patients who underwent OPCAB using additional free arterial or saphenous vein grafts that were anastomosed on the ascending aorta (group II) and 76 consecutive patients who underwent on-pump conventional coronary artery bypass grafting (group III).

RESULTS

No significant differences were noted in operative mortalities among the three groups (2/222, 3/123, and 2/76 in groups I, II, and III, respectively; p = NS). Fewer distal anastomoses were done in group I compared with groups II and III (3.2 +/- 0.9, 3.5 +/- 0.8, and 3.7 +/- 0.9 in groups I, II, and III, respectively; p < 0.001). No differences were noted in the incidences of postoperative morbidities such as mediastinitis, pulmonary complication, and reoperation for bleeding. The incidences of stroke, atrial fibrillation, and acute renal failure were significantly lower in group I than in group III (p < 0.05), although there were no significant differences between groups II and III. The incidence of perioperative myocardial infarction was significantly lower in group I than in groups II and III (p < 0.05), although there was no significant difference between groups II and III.

CONCLUSIONS

Our results demonstrate that OPCAB with complete avoidance of aortic manipulation may further reduce the incidence of perioperative morbidities such as stroke, atrial fibrillation, acute renal failure, and perioperative myocardial infarction.

Off-pump coronary artery bypass grafting: new developments but a better outcome?

Off-pump coronary artery surgery is now performed safely and effectively without cardiopulmonary bypass. This review includes indications, approaches, anaesthetic and haemodynamic management, and compares the occurrence of postoperative complications and multiorgan dysfunction with conventional cardiac surgery.

No decrease in incidence of atrial fibrillation in patients undergoing off-pump coronary artery bypass grafting

BACKGROUND

With the introduction of beating heart surgery, there has been a renewed interest in the incidence of postoperative atrial fibrillation (AF) in patients undergoing coronary artery bypass grafting (CABG). A small number of studies have reported markedly decreased incidences of postoperative AF in patients undergoing off-pump CABG.

AIMS

The aim of the present study was to review the incidence of AF in patients undergoing off-pump CABG at Royal Melbourne Hospital.

METHODS

A retrospective review was undertaken of 80 patients who had elective first-time CABG off-pump over a 16-month period. These patients were matched with 80 patients who underwent CABG with cardiopulmonary bypass (CPB). Data on preoperative and operative variables were collected. Incidences of postoperative AF in both groups were recorded.

RESULTS

The incidence of AF in the off-pump group was 27 of 80 patients (34%) and in the CPB group it was 25 of 80 patients (31%; NS). Increasing age was a significant risk factor for developing postoperative AF, and beta-blockade was identified as a protective factor.

CONCLUSIONS

Off-pump CABG does not decrease the incidence of postoperative atrial fibrillation. A randomised prospective trial has been commenced at Royal Melbourne Hospital to further investigate postoperative outcomes of off-pump CABG.

Did the introduction of a minimally invasive technique change the incidence of atrial fibrillation after single internal thoracic artery-left anterior descending artery grafting?

OBJECTIVE

Atrial fibrillation after coronary artery bypass operations remains frequent and increases morbidity, as well as resource use. Its cause remains unclear. The introduction of a minimally invasive technique provides an opportunity to evaluate the effect of intraoperative factors, such as cardiopulmonary bypass, global myocardial ischemia, and myocardial protection technique, on the occurrence of this arrhythmia.

METHODS

All the patients undergoing isolated left internal thoracic artery-left anterior descending artery grafting between January 1994 and December 1999 were reviewed. Twenty possible risk factors for postoperative atrial fibrillation, including the choice of operative technique--minimally invasive technique was introduced in January 1997--were entered into univariate and multivariable logistic regression analysis.

RESULTS

Postoperative atrial fibrillation occurred in 36 (20%) of 183 patients. On univariate analysis, age (P <.001) and a history of supraventricular arrhythmia (P <.001) were found to be risk factors. In particular, 15 (22%) of 69 patients operated on with the minimally invasive technique had postoperative atrial fibrillation versus 21 (18%) of 114 in the standard group (P =.58). On multivariable analysis, including the operative technique, the same variables (P =.001 and.01, respectively) were identified as independent risk factors.

CONCLUSIONS

The introduction of a minimally invasive technique for coronary artery bypass operations did not reduce the occurrence of postoperative atrial fibrillation in this study population. This suggests that prophylactic measures to reduce this arrhythmia should be focused on factors unrelated to cardiopulmonary bypass or myocardial preservation technique.

Postoperative neurologic assessment and management of the cardiac surgical patient

The neurologic evaluation of patients in the immediate postoperative period and postanesthetic state is unique and challenging. Neurologic assessment is complicated by the lingering residual effects of anesthetics as well as by the effects of narcotic analgesics, anxiolytics, and muscle relaxants, especially in ventilated patients. In this review we examine the suspected causes, clinical manifestations, diagnostic options, and intervention schemes for the common neurologic syndromes seen after cardiac operations.