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

Prevention of Cognitive Frailty in Patients of Older Age Groups after Open-Heart Surgery under Cardiopulmonary Bypass

Acute change in mental state is characterized by an impaired level of consciousness, decreased attention, and cognitive changes, and has a variable course throughout its period. Delirium is common in the elderly and hospitalized patients, especially after major surgeries, and increases mortality and morbidity in patients. This study was designed to investigate the relationship between the incidence of delirium after heart surgery and some intrusive factors during surgery. A total of 263 middle-aged, elderly, and chronic patients with functional class III-IV heart failure were classified based on the New York Heart Association classification and valvular heart disease. Cognitive impairment screening was performed using the Mini-Cog test and clock drawing test in addition to standard general clinical examinations on patients. Cognitive impairment was diagnosed in patients with coronary heart disease preparing for planned surgical treatment, regardless of age, while the results of both tests were significantly worse in elderly patients than in their middle-aged counterparts. In the early postoperative period, both among the middle-aged and elderly patients, there was a significant improvement in the results of the clock drawing test. Middle-aged patients also showed improved results on the Mini-Cog test, while the elderly patients showed an increase in cognitive dysfunction. In the third stage of the examination of cognitive function in the two studied groups of patients with valvular pathology at the first checkpoint, no statistically significant differences were found in the Mini-Mental State Examination (MMSE), Mini-Cog, and clock drawing test. The results of the clock drawing test in the main and control groups were recorded at 8.9±0.4 and 5.8±0.3 points, respectively (P<0.05). The MMSE results were estimated at the points of 27.1±0.1 and 24.1±0.2 in the main and control groups, respectively, while the results of the Mini-Cog test were calculated at 2.2±0.2 and 1.2±0.4 words in the main and control group, respectively (P<0.05). The application of the algorithm for the prevention of cognitive frailty in patients of older age groups after open-heart surgery under cardiopulmonary bypass would possibly lead to a decrease in the number of early and late postoperative complications, which shows the necessity of using it for patients of older age groups in multimodal programs to prepare them for surgical interventions.

The effect of opium addiction on short-term postoperative outcomes after coronary artery bypass graft surgery: A prospective observational cohort study

Introduction

Opium addiction has been recently suggested as a potential risk factor for the occurrence of perioperative complications in patients undergoing coronary artery bypass graft (CABG) surgery. The aim of this study was to evaluate whether opium addiction can potentially affect patients' short-term postoperative outcomes after CABG surgery.

Material and methods

In a prospective observational cohort study, all consecutive patients who were scheduled for first-time isolated elective on pump CABG surgery were screened during the study period for opium addiction. The study was carried out between September 2015 and November 2016 at Mazandaran Heart Center, Sari, Iran. A total number of 228 patients [110 opium addicted (OA) and 118 non-addicted (NA)] were screened and included. All patients were evaluate, in terms of short-term postoperative outcomes, until hospital discharge or death.

Results

In the OA patients, the mean amount of estimated postoperative bleeding was significantly more than NA patients (535 ± 304.75 ml vs. 463.56 ± 209.77; P = 0.04). Mean ventilation time were significantly longer in the OA patients than in the NA (9.9 days vs. 8.66 days, P = 0.02). The mean duration of postoperative hospital stay was two days longer in the OA (10.83 days vs. 8.34 days, P < 0.001). Also, the mean use of packed cell during surgery and incidence of postoperative atrial fibrillation were higher in the OA patients than NA (P = 0.005).

Conclusion

The results of our study provide strong evidence that the opium addiction should be considered as a risk factors for developing perioperative complications, including higher mean postoperative bleeding, need for intraoperative packed red blood cell transfusion, ventilation time and length of hospital stay, in patients undergoing CABG surgery.

Prospective evaluation of the utility of CHA2DS2-VASc score in the prediction of postoperative atrial fibrillation after off-pump coronary artery bypass surgery - An observational study

Introduction:

Off-pump coronary artery bypass (OPCAB) surgery is associated with evasion of complications of cardiac bypass. The incidence of postoperative atrial fibrillation (POAF) may also be reduced because of less ischemia and inflammation.

Aim:

Prospective evaluation of utility of CHA₂DS₂-VASc score in the prediction of POAF after OPCAB surgery.

Methodology:

In this prospective, observational study, 99 patients who underwent elective isolated OPCAB surgery were included. Patients with pacemaker in situ, receiving antiarrhythmic drugs preoperatively, and preexisting atrial fibrillation were excluded. A detailed history taking and physical examination were done preoperatively and the CHA₂DS₂-VASc scores were calculated for each patient. They received a standard anesthetic including midazolam, fentanyl, propofol, vecuronium, and isoflurane. The number of grafts, inotrope usage, and blood product transfusion in the perioperative period were noted. Patients were followed up for 5 days after surgery for development of new onset POAF requiring treatment.

Results:

About 20 of the 99 patients developed POAF. POAF occurred most commonly on postoperative day 2. They were older, more likely diabetic, had preoperative diastolic dysfunction, and received blood products perioperatively. POAF group had higher mean CHA₂DS₂-VASc score (3.6 ± 0.821 vs. 2.11 ± 1.35) and had longer hospital stay (16.85 ± 8.61 vs. 12.6 ± 4.05 days) than no POAF group. The cutoff for CHA₂DS₂-VASc score was 3, which showed 90% sensitivity, 77.22% specificity, 50% positive predictive value, and 96.63% negative predictive value.

Conclusions:

CHA₂DS₂-VASc score is useful in predicting POAF after OPCAB surgery. Higher the CHA₂DS₂-VASc score, greater is the possibility of development of POAF.

Effect of vitamin D deficiency on the development of postoperative atrial fibrillation in coronary artery bypass patients

Introduction: Various factors may be responsible for the development of postoperative atrial fibrillation (POAF) in coronary artery bypass graft (CABG) patients. In our study, we demonstrated the effect of vitamin D deficiency on the development of POAF. Methods: In this prospective case control study, patients undergoing elective, isolated CABG were considered. A total of 15 patients (16.6%) who developed POAF during the first five days after surgery made up the POAF group. Seventy-five patients that had a sinus rhythm in the same period were the non-POAF group. The two groups were compared statistically in terms of laboratory, clinical, echocardiographic, operative, and postoperative parameters. Results: All patients were in sinus rhythm at discharge. The baseline characteristics of the study groups were comparable. The POAF group had a lower vitamin D level than the non-POAF group (9.0 ± 5.0 and 15.0 ± 8.4 ng/mL, respectively; P=0.007). In the POAF group, the patients' left atrium diameter and incidence of hypertension (HT) were higher than those of the non-POAF group. Conclusion: Incidence of POAF was significantly higher in patients with vitamin D deficiency or insufficiency than the patients with vitamin D level in normal range. Therefore vitamin D deficiency or insufficiency may be a predictor of POAF in patients with CABG.

Atrial Fibrillation After Cardiac Surgery: Pathophysiology and Treatment

Atrial fibrillation (AF) occurs in 25% to 60% of patients after cardiac surgery. It is most consistently associated with advanced age and valvular heart operations. Despite improving knowledge of the pathophysiology of chronic AF, postoperative AF remains an obstinate clinical problem. It is associated with an increased risk of stroke, longer hospital stay, and higher hospital expenditure. Consequently, there has been great interest in strategies to prevent and treat this arrhythmia. Treatment for postoperative AF may require immediate electrical cardioversion for hemodynamically unstable patients. Heart rate control is useful in most patients, with anticoagulation considered after 48 hours. Antiarrhythmic therapy is often effective in restoring sinus rhythm but its use needs to be balanced against the patient's risk of proarrhythmic side effects such as torsade de pointes.

Statin therapy in the primary prevention of early atrial fibrillation after coronary artery bypass grafting

OBJECTIVE

Assessment of the role of statin therapy in the prevention of postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG) in patients without prior atrial fibrillation.

METHODS

A retrospective analysis of 206 patients, aged 57.2±7.9 years (mean±SD), who underwent isolated CABG is carried out. All patients are divided into two groups. The first group (nSt-patients) includes the patients who did not receive statin therapy prior to CABG (n=82). The second group (St-patients) includes the patients who received statin therapy prior to CABG (n=124). Both groups received the statin therapy from the first day after CABG. The risk of occurrence of POAF is evaluated using the Cox-regression model.

RESULTS

The rate of POAF was 25.6% in nSt-patients and 6.5% in St-patients (P=0.020). On the 4th day after CABG, white blood cells (WBC) count was 11.0 (9.0, 13.0)×10⁹/mL (medians with inter-quartile ranges) in nSt-patients and 9.0 (7.6, 10.2)×10⁹/mL in St-patients (P<0.001). The peak WBC numbers occurred on the day of POAF onset. The Cox-regression analysis shows that only two factors (statin therapy and number of grafts) had significant influence on the POAF onset. Odds ratio of POAF event prediction by statin therapy was 0.20 (95%CI: 0.08-0.51), P<0.001. Each subsequent graft increased the risk of POAF in 2.1 times.

CONCLUSION

Statin therapy carried out prior to the CABG is an effective approach to primary prevention of POAF in early postoperative period. Statin therapy after CABG in nSt-patients does not give prophylactic effect observed in St-patients.

Factors associated with extubation time in coronary artery bypass grafting patients

Background and Objectives. Cardiovascular diseases are the leading cause of death worldwide, with coronary artery disease being the most common. With increasing numbers of patients, Coronary Artery Bypass Grafting (CABG) has become the most common operation in the world. Respiratory disorder is one of the most prevalent complications of CABG. Thus, weaning off the mechanical ventilation and extubation are of great clinical importance for these patients. Some post-operative problems also relate to the tracheal tube and mechanical ventilation. Therefore, an increase in this leads to an increase in the number of complications, length of hospital stay, and treatment costs. Since a large number of factors affect the post-operative period, the present study aims to identify the predictors of extubation time in CABG patients using casualty network analysis.

Method. This longitudinal study was conducted on 800 over 18 year old patients who had undergone CABG surgery in three treatment centers affiliated to Shiraz University of Medical Sciences. The patients’ information, including pre-operative, peri-operative, and post-operative variables, was retrospectively extracted from their medical records. Then, the data was comprehensively analyzed through path analysis using MPLUS-7.1 software.

Results. The mean of extubation time was 10.27 + 4.39 h. Moreover, extubation time was significantly affected by packed cells during the Cardiopulmonary Bypass (CPB), packed cells after CPB, inotrope use on arrival at ICU, mean arterial pressure 1st ICU, packed cells 1st ICU, platelets 1st ICU, Blood Urea Nitrogen 1st ICU, and hematocrit 1st ICU.

Conclusion. Considering all of the factors under investigation, some peri-operative and post-operative factors had significant effects. Therefore, considering the post-operative factors is important for designing a treatment plan and evaluating patients’ prognosis.

Low Circulating Levels of Growth Differentiation Factor-15 Before Coronary Artery Bypass Surgery May Predict Postoperative Atrial Fibrillation

OBJECTIVES

To assess the role of growth differentiation factor-15 (GDF-15) as a potential new predictor of postoperative atrial fibrillation (POAF) after off-pump (OFP) and on-pump (ONP) coronary artery bypass graft (CABG) surgery.

DESIGN

Prospective, single-center, observational study.

SETTING

University teaching hospital.

PARTICIPANTS

The first 50 patients planned for OFP surgery and the first 50 patients planned for ONP surgery among patients referred for CABG with the following exclusion criteria: age<18 or>80 years, previous atrial fibrillation/flutter, previous treatment with amiodarone, previous cardiac surgery, and emergency surgery.

INTERVENTIONS

Included patients were equipped with long-duration (7 days) Holter-ECG monitoring.

MEASUREMENTS AND MAIN RESULTS

POAF was defined as an AF episode lasting>30 seconds. All patients underwent preoperative echocardiography to assess left ventricular ejection fraction and left atrial diameter. GDF-15 levels were assessed after induction of anesthesia and 12 hours after arrival at the intensive care unit. Among the 100 patients, 34 (34%) developed POAF. In Cox multivariate regression analysis, the EuroSCORE, left atrial diameter>45 mm, and low GDF-15 levels at induction were associated independently with the onset of POAF. In contrast, preoperative NT-proBNP levels did not predict POAF. The use of ONP surgery was not associated with a higher incidence of POAF, even though baseline and follow-up characteristics in ONP and OFP patients were identical.

CONCLUSIONS

In patients with no history of AF, a low plasma level of GDF-15 before CABG surgery was a strong independent predictor of POAF. Moreover, preoperative plasma GDF-15 levels added an incremental predictive value to classic risk factors of POAF.

The occurrence of postoperative atrial fibrillation according to different surgical settings in cardiac surgery patients

OBJECTIVES

Atrial fibrillation is the most common arrhythmia after cardiac surgery. The pathogenesis of postoperative atrial fibrillation is multifactorial. The aim of the study was to analyse preoperative, intraoperative and postoperative factors and their relationships with the occurrence and duration of atrial fibrillation.

METHODS

One hundred and ninety-six patients with coronary heart disease (152 men, age 62.7 ± 10.1 years) underwent surgical revascularization. Extracorporeal circulation was used in 64 patients and minimal extracorporeal circulation was used in 75 patients. Fifty-seven patients underwent surgery without extracorporeal circulation. During the first three postoperative days, subjects were monitored for the duration and incidence of atrial fibrillation, laboratory markers of inflammation (C-reactive protein, leucocytes) and serum potassium.

RESULTS

Demographic data and associated cardiovascular diseases in the groups were not statistically different. The overall incidence of atrial fibrillation was 56% (110 patients). The highest incidence of atrial fibrillation was found in the extracorporeal circulation subgroup, with a significantly lower incidence using minimal extracorporeal circulation, and in patients operated on without extracorporeal circulation (75 vs 47 vs 46%, P <0.001). The longest duration of atrial fibrillation was found in patients operated on with extracorporeal circulation compared with minimal extracorporeal circulation, and without extracorporeal circulation (9.7 ± 11.6 vs 4.9 ± 8.3 vs 3.1 ± 5.2, P ≤0.001). The incidence of postoperative atrial fibrillation significantly correlated with elevation of inflammatory markers (C-reactive protein, leucocytes) compared with patients who were free of atrial fibrillation (P ≤0.001, P ≤0.05). The values of serum potassium were not significantly different. The relationship between postoperative atrial fibrillation and echocardiographic parameters was not confirmed.

CONCLUSIONS

The use of extracorporeal circulation leads to a higher incidence of postoperative atrial fibrillation compared with the use of minimal extracorporeal circulation or with surgery without extracorporeal circulation, probably due to enhanced systemic inflammatory response.

Preoperative treatment with an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker has no beneficial effect on the development of new-onset atrial fibrillation after off-pump coronary artery bypass graft surgery

BACKGROUND

The present study investigated whether preoperative angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) use affected the incidence of postoperative atrial fibrillation (POAF) in patients undergoing off-pump coronary artery bypass graft (OPCAB).

HYPOTHESIS

Preoperative use of ACEI or ARB was related to POAF in patients undergoing OPCAB.

METHODS

This retrospective, observational, cohort study involved 1050 patients who underwent OPCAB from January 2006 to December 2009.

RESULTS

ACEI or ARB, ACEI alone, and ARB alone did not exert beneficial effect on the occurrence of POAF, and ACEI or ARB use was rather associated with an increased incidence of POAF (ACEI or ARB: odds ratio [OR]: 1.66, 95% confidence interval [CI]: 1.04-2.62, P = 0.03; ACEI alone: OR: 1.30, 95% CI: 0.57-2.97, P = 0.53; ARB alone: OR: 1.57, 95% CI: 0.93-2.64, P = 0.09).

CONCLUSIONS

ACEI or ARB, ACEI alone, and ARB alone did not favorably influence the occurrence of POAF in patients undergoing OPCAB.

Beating Heart versus Conventional Coronary Bypass Surgery: Our Experience

BACKGROUND

Off-pump Coronary Artery Bypass (OPCAB) has become the standard surgical treatment of Coronary Artery Disease in most centres in India. It is clear from the current evidence that, in certain patients, OPCAB offers advantages over conventional Coronary Artery Bypass Grafting (CABG). Experience of this procedure in the Armed Forces is highlighted.

METHODS

Retrospective analysis of 200 nonrandomized consecutive patients taken up for OPCAB and 200 conventional CABG between Jan 2005 and Dec 2007 was done. The European system for cardiac operative risk evaluation (euroSCORE) was used in all patients. Perioperative morbidity and mortality was compared in the two groups.

RESULT

OPCAB was possible in 192 (96 %) out of 200 patients taken up for this procedure. Eight patients required cardiopulmonary bypass (CPB) to complete the revascularization. Incidence of reoperation for bleeding was 2.5% in OPCAB and 6% in CABG In the CABG group 2% patients developed severe bleeding complications, 3% required ventilation for more than 24 hour, 1% required renal replacement therapy, 1% had acute respiratory distress syndrome and 3.5% had neuro-psychiatric manifestations. Incidence of these complications in OPCAB patients was lower or NIL. Overall mortality in the OPCAB group was 1.5% and 2% in the CABG group. However only one patient out of 192 (0.5%) who underwent successful OPCAB died, while two patients out of eight who required conversion to CPB in this group died. Incidence of stroke, deep sternal infection and mortality was similar in both groups.

CONCLUSION

OPCAB is safe, effective and can be offered to more than 90% patients as the primary strategy for surgical myocardial revascularization. It has lower overall morbidity than conventional CABG Its main limitations are hemodynamic instability and inability to find a deeply embedded target vessel. Both these factors affect the outcome adversely making conventional CABG a better option in these situations.

Left-ventricular electromechanical delay is prolonged in patients with postoperative atrial fibrillation

OBJECTIVE

Although several risk factors for postoperative atrial fibrillation (AF) have been proposed, it remains the most common complication after cardiac surgery, even in low-risk patients. There is still no single reliable and reproducible parameter for predicting AF, and no standardized recommendation exists for this issue. Electromechanical delay (excitation-contraction coupling delay) is the time delay from the electrical activation to the actual systolic motion, and it reflects abnormality in calcium-handling proteins, which is considered one mechanism of postoperative AF. We hypothesized that left-ventricular electromechanical delay (LVEMD) is correlated to postoperative AF and serially examined it by echocardiography.

METHODS

We prospectively included 16 patients with relatively low risk for AF, who underwent cardiac surgery. The inclusion criteria were younger than 80 years, an ejection fraction greater than 45%, a left-atrial dimension less than 50mm, and a brain natriuretic peptide (BNP) value less than 250 pg ml⁻¹. Postoperative AF for 10 postoperative days was monitored by 24-h electrocardiogram. The LVEMD was assessed by pulse-wave tissue Doppler echocardiography before and 1, 3, and 7 days after the operation. Serum BNP, adrenalin, and noradrenalin levels were also examined at the same time.

RESULTS

Postoperative AF was detected in six (37.5%) patients. There was no significant difference in heart rate, QRS duration, and serum hormones between the non-AF (n = 10) and AF (n = 6) groups. Although the preoperative LVEMD was comparable, that on postoperative day 1 of the AF group was significantly longer than that of the non-AF group (in the septal wall, 174 ± 50 vs 101 ± 36 ms, p = 0.020; in the lateral wall, 195 ± 71 and 111 ± 37 ms, p = 0.029). A LVEMD on postoperative day 1 greater than 150 ms well predicted postoperative AF (sensitivity, 75% and 75%; specificity, 100% and 86%, in septal and lateral LVEMDs, respectively).

CONCLUSIONS

LVEMD is prolonged in patients with postoperative AF. This could be a new predicting parameter for AF in low-risk patients.

Hsp70 and cardiac surgery: molecular chaperone and inflammatory regulator with compartmentalized effects

Open heart surgery is a unique model to study the interplay between cellular injury, regulation of inflammatory responses and tissue repair. Stress-inducible heat shock protein 70-kDa (Hsp70) provides a molecular link between these events. In addition to molecular chaperoning, Hsp70 exerts modulatory effects on endothelial cells and leukocytes involved in inflammatory networks. Hsp70 residing in the intracellular compartment is part of an inhibitory feedback loop that acts on nuclear factor kappaB (NF-kappaB). In contrast, extracellular Hsp70 is recognized by multiple germline-encoded immune receptors, e.g., Toll-like receptor (TLR) 2, TLR4, LOX-1, CD91, CD94, CCR5 and CD40. Hsp70 is thereby able to enhance chemotaxis, phagocytosis and cytolytic activity of innate immune cells and stimulate antigen-specific responses. These apparent contradictory pro- and anti-inflammatory effects of endogenous Hsp70 in the context of cardiac surgery are still not fully understood. An all-embracing model of the compartmentalized effects of endogenous Hsp70 in the orchestration of inflammatory responses in cardiac surgery is proposed.

Brain natriuretic peptide concentration in pericardial fluid is independently associated with atrial fibrillation after off-pump coronary artery bypass surgery

OBJECTIVES

Postoperative atrial fibrillation is associated with the increased incidence of morbidities and mortality. Predisposing determinants of atrial fibrillation development after off-pump coronary artery bypass grafting remain unclear. We hypothesized that pericardial fluid natriuretic peptide concentrations have a predictive value for developing postoperative atrial fibrillation in patients who have undergone off-pump coronary artery bypass grafting.

METHODS

We prospectively measured atrial natriuretic peptide and brain natriuretic peptide concentrations in plasma and pericardial fluid in 42 consecutive patients undergoing off-pump coronary artery bypass grafting, then continuously observed the occurrence of atrial fibrillation following off-pump coronary artery bypass grafting until the time of discharge.

RESULTS

Postoperative atrial fibrillation was documented in nine patients (21%, atrial fibrillation group), and not in 33 patients (no atrial fibrillation group). Between the groups, there was neither significant difference in plasma atrial natriuretic peptide concentrations nor in pericardial atrial natriuretic peptide concentrations. Plasma brain natriuretic peptide concentrations were comparable in both groups [56.2 (interquartile range 42.7-102.8) vs. 35.2 pg/ml (13.8-75.0), P=0.07]. Pericardial fluid brain natriuretic peptide concentrations were significantly higher in the atrial fibrillation group than in the no atrial fibrillation group [188.0 (124.8-411.0) vs. 39.3 pg/ml (10.0-88.4), P=0.0001]. In a multivariable logistic regression model, pericardial brain natriuretic peptide concentration was significantly associated with a higher risk of postoperative atrial fibrillation (odds ratio=3.0 every 50 pg/ml increase; 95% confidence interval, 1.1-8.6; P=0.04).

CONCLUSION

Our results suggested that pericardial fluid brain natriuretic peptide concentration is independently associated with the development of atrial fibrillation after off-pump coronary artery bypass grafting.

Post-operative atrial fibrillation is influenced by beta-blocker therapy but not by pre-operative atrial cellular electrophysiology

INTRODUCTION

We investigated whether post-cardiac surgery (CS) new-onset atrial fibrillation (AF) is predicted by pre-CS atrial cellular electrophysiology, and whether the antiarrhythmic effect of beta-blocker therapy may involve pre-CS pharmacological remodeling.

METHODS AND RESULTS

Atrial myocytes were obtained from consenting patients in sinus rhythm, just prior to CS. Action potentials and ion currents were recorded using whole-cell patch-clamp technique. Post-CS AF occurred in 53 of 212 patients (25%). Those with post-CS AF were older than those without (67 +/- 2 vs 62 +/- 1 years, P = 0.005). In cells from patients with post-CS AF, the action potential duration at 50% and 90% repolarization, maximum upstroke velocity, and effective refractory period (ERP) were 13 +/- 4 ms, 217 +/- 16 ms, 185 +/- 10 V/s, and 216 +/- 14 ms, respectively (n = 30 cells, 11 patients). Peak L-type Ca(2+) current, transient outward and inward rectifier K(+) currents, and the sustained outward current were -5.0 +/- 0.5, 12.9 +/- 2.4, -4.1 +/- 0.4, and 9.7 +/- 1.0 pA/pF, respectively (13-62 cells, 7-19 patients). None of these values were significantly different in cells from patients without post-CS AF (P > 0.05 for each, 60-279 cells, 29-86 patients), confirmed by multiple and logistic regression. In patients treated >7 days with a beta-blocker pre-CS, the incidence of post-CS AF was lower than in non-beta-blocked patients (13% vs 27%, P = 0.038). Pre-CS beta-blockade was associated with a prolonged pre-CS atrial cellular ERP (P = 0.001), by a similar degree (approximately 20%) in those with and without post-CS AF.

CONCLUSION

Pre-CS human atrial cellular electrophysiology does not predict post-CS AF. Chronic beta-blocker therapy is associated with a reduced incidence of post-CS AF, unrelated to a pre-CS ERP-prolonging effect of this treatment.

C-reactive protein is a risk indicator for atrial fibrillation after myocardial revascularization

BACKGROUND

Activation of the complement system after coronary artery bypass graft surgery involves C-reactive protein (CRP). This inflammatory response is related to baseline CRP levels and associated with postoperative arrhythmia, in particular atrial fibrillation (AF). We investigated whether baseline CRP levels are a risk indicator for the occurrence of AF and whether this phenomenon is cardiopulmonary bypass dependent.

METHODS

C-reactive protein was measured in perioperative blood samples of patients of the Octopus Study (coronary artery bypass graft surgery with [n = 73] or without cardiopulmonary bypass [n = 79]). Baseline CRP was dichotomized into a low and a high baseline group, using a cutoff value of 3.0 mg/L.

RESULTS

After coronary artery bypass graft surgery with cardiopulmonary bypass 11 of 53 patients (21%) with low preoperative CRP levels had AF versus 11 of 20 patients (55%) with high baseline CRP levels (p = 0.01). In the off-pump group AF occurred in 4 of 52 patients (8%) who had low baseline CRP levels, versus 8 of 27 patients (30%) with high preoperative CRP levels (p = 0.002). After adjusting for age, the odds ratio (95% confidence interval) was 4.6 (1.4 to 15.3) with cardiopulmonary bypass, 3.7 (0.93 to 14.7) in the off-pump group, and 3.3 (1.4 to 7.6) for both groups together. Continuous baseline CRP was an independent predictor for AF in a multivariate logistic regression model (p = 0.02).

CONCLUSIONS

Patients with high baseline CRP levels are at higher risk of having postoperative AF in both on-pump and off-pump surgery.

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.

Oral cibenzoline reduces postoperative atrial fibrillation in coronary artery bypass grafting

OBJECTIVE

The objective of the present study was to investigate the effectiveness of postoperative oral administration of cibenzoline for the prevention of atrial fibrillation (AF) in coronary artery bypass grafting (CABG).

METHODS

A total of 39 patients who underwent isolated CABG from September 2000 to February 2001 and who took oral cibenzoline (300 mg per day for 10 days beginning immediately after surgery) were compared to 59 patients who underwent surgery in our department 8 months prior to the study and who did not take cibenzoline for incidence of postoperative AF. Exclusion criteria encompassed age (>80 years), low ejection fraction (<30%), high serum creatinine level (>2.0 mg/dL), and history of supraventricular arrhythmia with or without treatment by anti-arrhythmic drugs.

RESULTS

Postoperative AF occurred in 2 patients in the cibenzoline group (2/35, 5.7%) and 20 patients in the control group (20/59, 33.9%). There were significant differences in the incidence of postoperative AF (p = 0.002). Multivariate analysis revealed that the administration of cibenzoline reduced the incidence of AF significantly, and that a large number of bypass grafts significantly contributed to postoperative AF in CABG. The number of bypass grafts was significantly larger in the cibenzoline group, indicating that cibenzoline administration significantly suppresses the incidence of AF after CABG in high-risk patients.

CONCLUSIONS

Postoperative administration of oral cibenzoline for 10 days is one effective method for the prevention of AF after CABG.

Pump or no pump for coronary artery bypass: current best available evidence

Coronary artery bypass grafting has been performed predominantly with the use of cardiopulmonary bypass and cardioplegic arrest, which allows optimization of the surgical field and consistent placement of grafts. However, the use of cardiopulmonary bypass is also associated with numerous complications. A surgical technique avoiding cardiopulmonary bypass should, in theory, reduce the incidence of such complications and lead to improved patient outcomes. This assumption has rekindled interest in performing off-pump coronary artery bypass surgery, which is currently the focus of scientific scrutiny. The existing world medical literature contains a staggering amount of research related to this technique. Although the available evidence from a large number of randomized clinical trials, nonrandomized clinical trials, propensity-matched analyses, and experimental data suggests that outcomes are better after off-pump than after on-pump coronary artery bypass surgery, skepticism still exists about the safety and efficacy of the off-pump technique. In the present era of evidence-based medicine, results from randomized clinical trials are given the highest recognition. This review attempts to evaluate the best currently available evidence from clinical trials about the safety and efficacy of off-pump coronary artery bypass surgery.

Coronary artery bypass graft surgery: discharge planning for successful recovery

BACKGROUND

Coronary artery bypass graft (CABG) surgery is a lifesaving intervention, but the early recovery period presents a number of challenges for patients, carers and nurses. Early and adequate discharge planning based on in-depth knowledge of the postdischarge experience can help to ensure optimal recovery.

AIM

This paper reports a study to examine the range of postdischarge issues, concerns and needs of patients and their family carers after discharge after CABG surgery, and explore their perceptions of unmet needs 1 year later.

METHODS

A two-phase naturalistic inquiry was undertaken. Interviews were conducted with 30 patients and their carers 4-5 weeks after coronary artery bypass grafting (phase 1) and 1 year after the initial interview (phase 2). Thematic analysis was used to identify the major concerns of participants.

FINDINGS

Almost half the patients experienced heart surgery as a huge personal shock. Adjusting to life afterwards was difficult, and they experienced a variety of changes, including pain. An unexpected finding was a heightened sense of body awareness and the need for postoperative physical adjustments. The financial implications of surgery were a major burden. Lifestyle adjustments were important and led to suggestions for support services, using telephone support and/or community patient networks. All participants recommended strengthening discharge planning with more accurate information about what to expect during recovery, to help them anticipate fluctuations in health and wellbeing. Carers experienced a wide range of unanticipated feelings during early recovery and had to deal with a number of personal changes.

CONCLUSIONS

The findings suggest a need to improve discharge preparation and provide enhanced home support services. Further research should evaluate models of periodic follow-up and mechanisms for mutual support, and compare the experiences of cardiac patients and their carers with those of other surgical cohorts.

Atrial pacing for the prevention of atrial fibrillation after coronary artery bypass graft surgery: a review of the literature

Atrial fibrillation (AF) occurs in 20-40% of patients after coronary artery bypass graft surgery (CABG) and contributes to increased morbidity and expenditure after CABG. The limited efficacy of pharmacological treatment to prevent post-CABG AF has stimulated research into alternative prophylactic strategies for the arrhythmia. This article critically reviews the trial evidence in the literature regarding the efficacy of epicardial atrial pacing to prevent post-CABG AF. Thirteen randomised controlled trials of either right, left, or biatrial pacing to prevent post-CABG AF were identified. Overall, prophylactic biatrial epicardial pacing appears to be effective prophylaxis against post-CABG AF and to reduce postoperative hospital stay. The efficacy of single site right or left atrial pacing is less clear. Further data are required to determine both the efficacy of single site atrial pacing and the cost effectiveness of pacing strategies to prevent AF after CABG.