Predictors of atrial fibrillation after off-pump coronary artery bypass graft surgery

OBJECTIVE: Atrial fibrillation is the most common complication after coronary artery bypass graft surgery. This arrhythmia may lead to hemodynamic compromise, prolonged hospitalization, and increased risk for cerebral thromboembolism. Older age is the only variable consistently associated with the development of postoperative atrial fibrillation; however, no strong predictive model exists. The purpose of this study was to identify perioperative characteristics associated with new-onset atrial fibrillation in patients undergoing off-pump coronary artery bypass grafting. DESIGN: Prospective, observational. SETTING: University tertiary care hospital. PARTICIPANTS: One hundred sixty consecutive patients undergoing off-pump coronary artery bypass grafting. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Incidence of postoperative atrial fibrillation was the major outcome. Atrial fibrillation occurred in 33 patients (20.6%). Multivariate analysis identified reintervention (odds ratio 26.8), revascularization of the ramus medianus (odds ratio 3.9), and age (odds ratio 1.069 per year) as the only independent predictors of postoperative atrial fibrillation. All patients were in sinus rhythm at hospital discharge. One hospital death was noted. CONCLUSIONS: Despite the less invasive approach, the incidence of postoperative atrial fibrillation is high after off-pump coronary artery bypass grafting. Older age, grafting of the ramus medianus, and a redo operation were predictors of new-onset postoperative atrial fibrillation. It is possible that left atrial stretching with heart dislocation during revascularization of the lateral wall could lead to postoperative atrial fibrillation.     

Perioperative magnesium supplementation to prevent atrial fibrillation after off-pump coronary artery surgery: a randomized controlled study

OBJECTIVE: Atrial fibrillation is a common complication after cardiac surgery. Magnesium is an effective and safe antiarrhythmic agent for arrhythmias that develop after cardiac surgery. The authors performed a study to evaluate the role of perioperative magnesium for prophylaxis of atrial fibrillation after off-pump coronary artery surgery. DESIGN: Randomized controlled study. SETTING: University teaching hospital. PARTICIPANTS: One hundred sixty consecutive patients undergoing elective, isolated, off-pump coronary artery bypass grafting were prospectively randomized into 2 groups. INTERVENTIONS: Patients in the magnesium group (n = 80) received a 2.5-g (20 mEq) magnesium sulphate infusion intraoperatively over 30 minutes, and the placebo group (n = 80) received normal saline solution. MEASUREMENTS AND MAIN RESULTS: Postoperative atrial fibrillation occurred in 16 of 80 patients (20%) in the magnesium group and in 18 of 80 (22.5%) in the placebo group (p = 0.9). CONCLUSION: The use of 2.5 g of intraoperative magnesium showed no effect in preventing atrial fibrillation after off-pump coronary artery bypass.     

Preoperative beta-blocker use reduces atrial fibrillation in off-pump coronary bypass surgery

BACKGROUND: Atrial fibrillation (AF) after coronary artery bypass graft surgery constitutes the most common sustained arrhythmia and results in many complications. The purpose of this study was to assess the effects of prophylactic use of beta-blockers against atrial fibrillation in off-pump surgery patients in the early postoperative period. METHODS: From 2002 to 2005, 78 patients were enrolled and 41 patients received 50 mg metoprolol succinate daily, which was initiated minimum four days before surgery. Preoperative beta-blocking therapy was continued until the morning of surgery. Thirty-seven patients were free of beta-blocker therapy. Esmolol was used within same range of doses in both groups during operations. Both groups received metoprolol succinate following operations. The frequency of AF occurrence was analysed from the operation time to the sixth postoperative day. Results: Sixteen patients developed AF with an overall incidence of 22.5%. Four patients from the study group and three patients from the control group were excluded from the study because of transfer to on-pump surgery. There was no difference with regard to the number of grafts carried out, duration of operations and ventilation, intensive care unit stay and inotropic need among groups. Length of hospital stay did not differ among groups either. There was a higher incidence of postoperative AF in patients without beta-blocker prophylaxis (11.7-32.4% P=0.049). CONCLUSION: Low-dose postoperative beta-adrenergic blockade is valuable for patients who receive these medications before off-pump coronary artery bypass grafting procedures and may be beneficial against AF in all patients.     

Impact of minimal invasive extracorporeal circulation on atrial fibrillation after coronary artery bypass surgery

Postoperative atrial fibrillation (POAF) is the most common arrhythmia after cardiac surgery with an incidence between 15% and 50% and pathophysiology not fully known. By choosing the method of extracorporeal circulation with focus on the reduction of systemic inflammatory response, one can potentially decrease the risk of POAF. In this prospective, randomized trial, we compared minimal invasive extracorporeal circulation (MiECC) with conventional extracorporeal circulation (CECC) in the prevention of POAF after coronary artery bypass surgery (CABG). A total of 240 patients who were scheduled for their first on-pump CABG, were randomized to MiECC or CECC. The primary outcome measure was the incidence of first POAF during the first 84 hours after surgery. POAF occurred in 42/120 (35.0%) MiECC patients and 43/120 (35.8%) CECC patients with nonsignificant difference between the groups (OR 1.043, 95% CI 0.591-1.843, P = .884). The first postoperative creatine kinase-MB mass (CK-MBm) value was lower in the MiECC group, 13.95 [10.5-16.7] (median [IQR]) than in the CECC group, 15.30 [11.4-18.9] (P = .036), whereas the use of perioperative dobutamine was higher in the MiECC group, 18/120 (15.0%), than in the CECC group 8/120 (6.7%) (P = .038). The incidence of a stroke, perioperative myocardial infarction, and resternotomy caused by bleeding did not differ in the MiECC and CECC groups. Age (OR 1.08, 95% CI 1.04-1.13, P = .000) and peak postoperative CK-MBm (OR 1.57, 95% CI 1.06-2.37, P = .026) were independent predictors of POAF. MiECC compared to CECC was not effective in reducing the incidence of POAF in patients undergoing CABG.     

Preoperative C-reactive protein and atrial fibrillation after off-pump coronary bypass surgery

Objective: The purpose of the present study was to investigate the association between preoperative C-reactive protein (CRP) and atrial fibrillation (AF) after isolated off-pump coronary bypass surgery. Methods: Of 683 consecutive patients undergoing isolated coronary bypass surgery by a single surgeon between January 2002 and March 2009, 552 were retrospectively analyzed after excluding the following 131 cases: on-pump surgery (n = 6), chronic AF (n = 14), pacemaker rhythm (n = 7), and preoperative CRP of ≥10 mg l⁻¹ (n = 104). We analyzed the correlation on a continuous basis per 1 SD increase in the logarithmically transformed value of CRP and on a group basis CRP level categorized into three groups: <1.0 mg l⁻¹, n = 196; 1.0–3.0 mg l⁻¹, n = 220; and 3.0–10.0 mg l⁻¹, n = 136. Results: AF occurred in 121 patients (21.9%, 121/552) of patients after surgery. The median value (interquartile range) of preoperative CRP (mg l⁻¹) was significantly higher in patients who developed AF than in those who did not (2.2 (1.0–4.2) vs 1.3 (0.6–2.5), p = 0.001). The rate of 7-day survival free from AF was 65.4% in patients with CRP of 3.0–10.0 mg l⁻¹, 79.9% in those with CRP of 1.0–3.0 mg l⁻¹, and 85.7% in those with CRP of <1.0 mg l⁻¹ (log-rank test: p = 0.001). The unadjusted hazard ratio (95% confidence interval) for the association between CRP and postoperative AF was 1.65 (1.32–2.06) per 1 SD increase and 3.17 (1.86–5.40) for patients with CRP of 3.0–10.0 mg l⁻¹ versus those with levels of <1.0 mg l⁻¹. This association persisted after adjustment for the univariate predictors (1.43 (1.22–1.97) per 1 SD increase; 2.88 (1.67–4.97) for patients with CRP of 3.0–10.0 mg l⁻¹ vs <1.0 mg l⁻¹) or the known risk factors (1.34 (1.18–1.86) per 1 SD increase; 2.52 (1.54–4.36) for patients with CRP of 3.0–10.0 mg l⁻¹ vs <1.0 mg l⁻¹). The area under the receiver operating characteristic curve (95% confidence interval) for preoperative CRP as a predictor of postoperative AF was 0.68 (0.62–0.74) (p = 0.001). Conclusions: Preoperative CRP is independently associated with the occurrence of AF after isolated off-pump coronary bypass surgery.     

Risk factors of atrial fibrillation following off-pump coronary artery bypass graft surgery: predictive value of C-reactive protein and transfusion requirement

Objectives: Considering the role of inflammatory reaction on the pathogenesis of atrial fibrillation (AF), the aim of this study is to investigate perioperative risk factors of AF, as well as to validate the predictive value of high-sensitive C-reactive protein (hsCRP), and transfusion requirement following off-pump coronary bypass surgery (OPCAB) in a prospective and observational trial. Methods: In this cohort, 315 consecutive patients with normal sinus rhythm (NSR) undergoing elective isolated OPCAB are prospectively studied. The patients were classified as either NSR or AF group according to their postoperative rhythm, which was continuously monitored for the first 6 postoperative days. Results: AF developed in 66 patients (19%). Univariate analysis demonstrated old age, pre-existing chronic renal failure, low left ventricle ejection fraction (LVEF <30%), highest hsCRP before the onset of AF, vasopressor and inotropic therapy, packed red blood cells (pRBCs) transfusion and amount of chest tube drainage as predictors of postoperative AF. In a stepwise multivariate analysis of these risk factors, low LVEF (odds ratio: 2.88; 95% confidence interval: 1.07–7.75; p = 0.037), highest hsCRP before the onset of AF (odds ratio: 1.06; 95% confidence interval: 1.01–1.11; p = 0.018), vasopressor therapy (odds ratio: 1.93; 95% confidence interval: 1.04–3.57; p = 0.038) and pRBC transfusion (odds ratio: 5.32; 95% confidence interval: 2.80–10.11; p < 0.001) remained as independent predictors of postoperative AF. Conclusions: Prophylactic strategies aimed at AF reduction may also be considered especially in patients with increased transfusion requirement, which showed highest predictive value for postoperative AF.     

Predictors of atrial fibrillation occurrence after coronary artery bypass graft surgery

Purpose  

Postoperative atrial fibrillation (AF) is the most common complication after coronary artery bypass graft (CABG) surgery, with an incidence of 20%–50%. The objective of this study was to investigate perioperative risk factors of postoperative sustained AF by the way of logistic regression analysis.     

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. β‐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.     

Preoperative plasma brain natriuretic peptide level is an independent predictor of postoperative atrial fibrillation following off-pump coronary artery bypass surgery

Purpose  Atrial fibrillation (AF) is a frequent complication after coronary artery bypass surgery. Postoperative AF can lead to thromboembolic events, prolonged hospital stay, and increased costs. Recent reports have shown that an elevated plasma brain natriuretic peptide (BNP) level is associated with AF. The purpose of this prospective study was to test the hypothesis that preoperative BNP level is a predictor of postoperative AF following off-pump coronary artery bypass surgery (OPCAB). Methods  One hundred and fifty patients without a history of AF undergoing elective isolated OPCAB were enrolled. Plasma BNP level was measured preoperatively. Heart rate and rhythm were continuously monitored during the first 72 h after surgery. Results  Twenty-six patients (17.3%) exhibited postoperative AF. This proportion is similar to those reported in earlier studies. Univariate analysis demonstrated that age (odds ratio [OR], 1.060; 95% confidence interval [CI], 1.008 to 1.114; P = 0.023), previous myocardial infarction (MI; OR, 2.628; 95% CI, 1.031 to 6.697; P = 0.043), and BNP level (OR, 7.336; 95% CI, 2.401 to 22.409 / log BNP level; P < 0.001) were accurate predictors of postoperative AF. Stepwise multivariate regression analysis indicated age (OR, 1.059; 95% CI, 1.002 to 1.120; P = 0.043) and BNP level (OR, 6.272; 95% CI, 1.980 to 19.861/log BNP level; P = 0.002) as the only independent predictors of postoperative AF. Conclusion  Preoperative BNP level is an independent predictor of postoperative AF following OPCAB. Our findings permit us to stratify the risk of AF and to plan prophylactic strategies in high-risk patients.     

Heart rate variability measures poorly predict atrial fibrillation after off-pump coronary artery bypass grafting

Study Objective

To investigate associations of heart rate variability (HRV) measurements with postoperative atrial fibrillation (AF) in patients undergoing off-pump coronary surgery.

Design

Prospective, observational, exploratory study.

Setting

Large university-affiliated community medical center.

Patients

50 patients undergoing off-pump coronary artery bypass grafting (CABG).

Interventions

Preoperative recording of electrocardiograms (ECGs) with subsequent off-line HRV analysis. Monitored ECG telemetry for 5 days after operation.

Measurements

Frequency and time domain analyses, and additional non-linear HRV determinations. Multivariate regression analysis of predictors of postoperative AF.

Main Results

AF occurred in 23 (46%) patients. Only the low to high-frequency ratio was associated with AF (2.35 ± 1.8 v. 4.57 ± 5.0 for patients without AF, P < 0.05).

Conclusions

The off-pump approach does not protect against AF, and nonlinear HRV analyses provide little value in predicting AF after off-pump CABG.     

高龄冠心病合并心房颤动患者行非体外循环冠状动脉旁路移植术中左心耳处理的回顾性队列研究

目的 本文旨在探讨左室射血分数(LVEF)降低的高龄冠心病合并心房颤动(房颤)患者在非体外循环冠状动脉旁路移植术(OPCABG)中同期处理左心耳的手术技巧及效果评价.方法 纳入2013～ 2018年,84例OPCABGLVEF降低(＜50％)的高龄(年龄≥70岁)冠心病合并房颤患者在我科行非体外循环冠脉搭桥术.男54例...     

Postoperative atrial fibrillation: a comparison of off-pump coronary artery bypass surgery and conventional coronary artery bypass graft surgery

OBJECTIVE: To compare the incidence and pattern of onset of postoperative atrial fibrillation (AF) in patients undergoing coronary artery bypass graft (CABG) surgery with and without cardiopulmonary bypass (CPB). DESIGN: Retrospective, cohort-controlled study. SETTING: University hospital and tertiary referral center. PARTICIPANTS: A group of 108 consecutive patients who underwent primary off-pump coronary artery bypass (OP-CAB) surgery and a control group of 100 patients who underwent CABG surgery with CPB. All patients underwent surgery between January and September 1999. INTERVENTIONS: Patients in the OP-CAB surgery group were operated on by either of 2 surgeons. The CABG surgery group was drawn from the general pool of patients operated on by 1 of 10 surgeons. All patients underwent median sternotomy and received standard anesthesia and intensive care unit management for this institution. MEASUREMENTS AND MAIN RESULTS: Data from 99 OP-CAB surgery patients (data incomplete in 9 patients) were compared with data from 100 CABG surgery patients. General demographics were similar except the CABG surgery group received a higher mean number of distal anastomoses (3.3 v 3.0; p = 0.028) The incidence of AF was similar in both groups (OP-CAB surgery, 25% v CABG surgery, 18%; p = 0.228). The peak incidence of AF was postoperative day 2 in both groups. The median hospital length of stay was increased in patients developing AF. CONCLUSION: Avoiding CPB does not seem to reduce the incidence of postoperative AF in CABG surgery. The similar time distribution of onset of AF in OP-CAB surgery patients and CABG surgery patients may point toward a common cause.     

Hemodynamic predictors of atrial fibrillation or flutter after coronary artery bypass grafting

The cumulated incidence of atrial fibrillation or flutter after coronary artery bypass grafting is 30%. The causes of these arrhythmias have not yet been sufficiently identified. We therefore undertook the present study to analyze the possible association of hemodynamic function during the various phases of coronary artery bypass grafting and the later development of atrial fibrillation/flutter.
Hemodynamic function was measured with a pulmonary artery catheter in 120 consecutive patients undergoing elective coronary artery bypass surgery.
Thirty-five (29%) of the patients developed atrial fibrillation/flutter. Logistic regression analysis identified independent predictors of atrial fibrillation/flutter: After induction of general anesthesia, the relative risk (95% confidence interval) of older age was 1.09/year (1.03–1.16), and the reduction in relative risk by an increase in left ventricular stroke work was 0.96/gm (0.93–0.99). After weaning from the extracorporeal circulation the independent significant predictors were age, relative risk 1.07/year (1.01–1.13), and increased central venous pressure, relative risk 1.12/mm Hg (1.00–1.26). At the time of admission to the intensive care unit, the relative risk of age was 1.10/year (1.03–1.18), and the relative risk of an increased central venous pressure was 1.26/mm Hg (1.06–1.49). However, the best prediction model (prediction after induction of general anesthesia) only provided a median predicted probability of atrial fibrillation/flutter of 0.37 for the patients who had atrial fibrillation/flutter, and a median predicted probability of atrial fibrillation/nutter of 0.20 for the patients without these arrhythmias. We identified possible hemodynamic predictors of atrial fibrillation/flutter after coronary bypass surgery, but the use of a risk stratification for development of atrial fibrillation/flutter based on hemodynamic function cannot be recommended.     

Continuous cardiac output during off-pump coronary artery bypass surgery: pulse-contour analyses vs pulmonary artery thermodilution

Background: No gold standard method exists for monitoring continuous cardiacoutput (CO). In this study, the agreement between the two mostfrequently used methods, PiCCO pulse-contour analysis (PCCO)and STAT pulmonary artery thermodilution (STAT-CO), was assessedduring multiple-vessel off-pump coronary artery bypass (OPCAB)surgery. Methods: Thirty patients were enrolled in the study. Two time periodswere defined during surgery; Period 1 included positioning ofthe heart and stabilizer device and Period 2 included the coronaryocclusion. Measurements were obtained every minute during bothperiods. The agreement for the continuous CO and the changein CO (CO) was estimated using the Bland–Altman method. Results: Significant changes in mean arterial pressure (MAP), centralvenous saturation, PCCO and STAT-CO were seen only during Period1. MAP correlated only with changes in PCCO, (P < 0.001,r = 0.60). The mean difference (2SD) between PCCO and STAT-COranged from – 0.29 (1.82) to – 0.71 (2.57) litremin^–1, and the percentage error varied from 32 to 50%.For the CO measurements, the limits of agreements did not differbetween Period 1 and Period 2. In contrast, for the CO measurements,the limits of agreements were wider in Period 1 than in themore haemodynamically stable Period 2. Conclusions: PCCO and STAT-CO show large discrepancies in CO during OPCABsurgery. Clinically acceptable agreement was seen only for trendsin CO during haemodynamically stable periods.     

冠状动脉旁路移植术后早期新发心房颤动的临床特征及影响因素分析

目的 探讨冠状动脉旁路移植术后新发心房颤动(房颤)的临床特征及影响因素.方法 回顾性分析2012年1月至2019年1月在我院行冠状动脉旁路移植术的339例患者的临床资料,其中男267例、女72例,年龄37～83(58.03±8.90)岁.分析术后新发房颤的临床特征及影响因素.结果 不停跳冠状动脉旁路移植(off-pum...     

Off-pump coronary artery bypass surgery: physiology and anaesthetic management

Increasing interest is being shown in beating heart (off-pump)coronary artery surgery (OPCAB) because, compared with operationsperformed with cardiopulmonary bypass, OPCAB surgery may beassociated with decreased postoperative morbidity and reducedtotal costs. Its appears to produce better results than conventionalsurgery in high-risk patient populations, elderly patients,and those with compromised cardiac function or coagulation disorders.Recent improvements in the technique have resulted in the possibilityof multiple-vessel grafting in all coronary territories, witha graft patency comparable with conventional surgery. Duringbeating-heart surgery, anaesthetists face two problems: first,the maintenance of haemodynamic stability during heart enucleationnecessary for accessing each coronary artery; and second, themanagement of intraoperative myocardial ischaemia when coronaryflow must be interrupted during grafting. The anaesthetic techniqueis less important than adequate management of these two majorconstraints. However, experimental and recent clinical datasuggest that volatile anaesthetics have a marked cardioprotectiveeffect against ischaemia, and might be specifically indicated.OPCAB surgery requires team work between anaesthetists and surgeons,who must be aware of each other’s constraints. Some surgicalaspects of the operation are reviewed along with physiologicaland anaesthetic data. Br J Anaesth 2004; 92: 400–13     

Safety of oral nicorandil before coronary artery bypass graft surgery

Nicorandil is a K_ATP channel opener used to treat angina. Itis cardioprotective and a vasodilator. We conducted a prospective,randomized, double-blind, placebo-controlled study to assessoral nicorandil in patients undergoing coronary artery bypassgrafting (CABG) with cardiopulmonary bypass (CPB). Twenty-twopatients received nicorandil (10 mg twice a day) and 23patients received placebo. Haemodynamic data were recorded beforeinduction of anaesthesia (T0), 5 and 20 min after startingmechanical ventilation (T1, T2), before aortic cannulation (T3),after 30 min of CPB (T4), 10 min after CPB (T5) andafter 3, 8 and 18 h in the intensive care unit (T6, T7,T8). Serum proteins (creatine kinase metabolite and cardiactroponin I) were measured before and 8 and 18 h after surgery.Haemodynamic values did not differ between the two groups. Therewas no tachycardia during the study, no significant differencein hypotensive episodes, ST segment changes and no changes incardiac enzymes. Myocardial infarction after surgery was similarin the two groups. Vasoactive therapy was similar in the twogroups. Nicorandil can be continued safely up to premedicationwithout deleterious haemodynamic consequences, but a myocardialprotective effect of nicorandil in CABG surgery was not found. Br J Anaesth 2001; 87: 848–54     

非体外循环冠状动脉旁路移植术后的阿司匹林抵抗

目的 通过检测非体外循环冠状动脉旁路移植术(OPCAB)后患者血小板聚集率以及尿11-脱氢-血栓烷B2(11-DH-TXB2)指标，动态观察术后阿司匹林抵抗(AR)的发生情况，探索术后AR的危险因素。方法 冠心病患者290例，首次行OPCAB患者145例(手术组)，接受内科药物治疗患者145例(非手术组)。手术组患者于术前及术后服用阿司匹林后第1、4、10天及6个月，检测血小板聚集率以及尿11-DH-TXB2。非手术组患者于服药前及服药后第1、4、10天检测上述指标。同时记录患者各项临床资料。结果 手术组患者服用阿司匹林后第1天的AR发生46例(32％)(抵抗组)，其余为非抵抗组。用药后第4天和第10天AR患者下降至19例(13％)和5例(3％)。半年随访中未发现有AR患者存在。非手术组患者，服药后第1天，血小板聚集率均下降至20％以下，平均(8.8±6.8)％，未见AR现象出现。手术组患者术后血小板计数显著高于术前(P＜0.05)。Logistic回归分析发现，OPCAB患者中，体重大于75 kg(OR =0.38，95％CI:0.18～0.79)和术后引流量超过500 ml(OR=3.12，95％CI:1.29～7.53)为术后出现AR的危险因素。结论 OPCAB术后早期，阿司匹林的抗血小板作用受到不同程度抑制，部分患者出现AR现象，予以更为积极有效的抗血小板治疗有重要临床意义。