Epidemiology, mechanisms, and risks - American College of Chest Physicians guidelines for the prevention and management of postoperative atrial fibrillation after cardiac surgery
ABSTRACT Atrial fibrillation (AF) is one of the most frequent complications of cardiac surgery, affecting more than one third of patients. The mechanism of this arrhythmia is believed to be reentry. The electrophysiologic substrate may be preexisting or may develop due to heterogeneity of refractoriness after surgery. Multiple perioperative factors have been proposed to contribute to the latter, including operative trauma, inflammation, elevations in atrial pressure (including that due to left ventricular diastolic dysfunction), autonomic nervous system imbalance, metabolic and electrolyte imbalances, or myocardial ischemic damage incurred during the operation. Whether ectopic beats originating in the pulmonary veins explain at least some episodes of postoperative AF, as has been shown for nonsurgical patients with the arrhythmia, is of current interest as such sites could easily be isolated at the time of surgery. The development of postoperative AF is associated with a higher risk of operative morbidity, prolonged hospitalization, and increased hospital cost compared with that in patients remaining in sinus rhythm. Many factors have been identified as being associated with postoperative AF, but the most consistent variable across studies is increasing patient age. It is speculated that age-related pathologic changes in the atrium contribute to arrhythmia susceptibility. An important modifiable risk factor for postoperative AF is the failure to resume therapy with beta-adrenergic receptor blockers after surgery. The stratification of patients who are at higher risk for AF would focus preventative strategies on patients who are most likely to benefit from such therapy. Nonetheless, since postoperative AF often develops in patients with comorbidities who are predisposed to other complications and prolonged hospitalization, it is presently unclear whether the prevention of postoperative AF will result in improved patient outcomes, particularly shorter hospitalizations.
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- "Thus the anti-inflammatory and antioxidant effects of atorvastatin as mentioned above may account for its beneficial effects in these patients. AF after coronary surgery is mainly caused by elevations in atrial pressure, autonomic nervous system imbalance, myocardial ischemic damage and so on , thus it can regress over time with surgery recovery. However, non-postoperative AF, especially recurrent AF, is often caused by atrial remodeling such as atrial dilation and fibrosis . "
ABSTRACT: Background A number of clinical and experimental studies have investigated the effect of atorvastatin on atrial fibrillation (AF), but the results are equivocal. This meta-analysis was performed to evaluate whether atorvastatin can reduce the risk of AF in different populations. Methods We searched PubMed, EMBASE and the Cochrane Database for all published studies that examined the effect of atorvastatin therapy on AF up to April 2014. A random effects model was used when there was substantial heterogeneity and a fixed effects model when there was negligible heterogeneity. Results Eighteen published studies including 9952 patients with sinus rhythm were identified for inclusion in the analysis. Ten studies investigated primary prevention of AF by atorvastatin in patients without AF, seven studies investigated secondary prevention of atorvastatin in patients with AF, and one study investigated mixed populations of patients. Overall, atorvastatin was associated with a decreased risk of AF (odds ratio (OR) 0.51, 95% confidence interval (CI) 0.36–0.70, P < 0.0001). However, subgroup analyses showed that in the primary prevention subgroup (OR 0.55, 95% CI 0.38–0.81, P = 0.002), atorvastatin reduced the risk of new-onset AF in patients after coronary surgery (OR 0.44, 95% CI 0.29–0.68, P = 0.0002), but had no beneficial effect in patients without coronary surgery (OR 0.97, 95% CI 0.59–1.58, P = 0.89); in the secondary prevention subgroup, atorvastatin had no beneficial effect on AF recurrence in patients with electrical cardioversion (EC) (OR 0.57, 95% CI 0.25–1.32, P = 0.19) or without EC (OR 0.38, 95% CI 0.14–1.06, P = 0.06). Conclusions This meta-analysis suggests that atorvastatin has an overall protective effect against AF. However, this preventive effect was not seen in all types of AF. Atorvastatin was significantly associated with a decreased risk of new-onset AF in patients after coronary surgery. Moreover, atorvastatin did not prove to exert a significant protective effect against the AF recurrences in both patients who had experienced sinus rhythm restoration by means of EC and those who had obtained cardioversion by means of drug therapy. Thus, further prospective studies are warranted.BMC Cardiovascular Disorders 08/2014; 14(1):99. DOI:10.1186/1471-2261-14-99 · 1.50 Impact Factor
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- "Several risk factors are associated with the occurrence of atrial fibrillation after cardiac surgery; they include mainly old age, low ejection fraction, and heart valve surgery. The onset of this arrhythmia is most likely a consequence of hemodynamic, electrical, and histological atrial tissue abnormalities related to intraoperative changes [20,21] and is associated with a higher incidence of early complications, such as congestive heart failure, stroke, renal dysfunction, infections, and neurocognitive impairment . Postoperative atrial fibrillation increases hospital stays and health care costs [22,23], so strategies to predict its occurrence may have important clinical and economic relevance by intensifying preoperative medical treatment, enabling the use of perioperative intensive prophylaxis schemes, or eventually leading to the use of intraoperative ablation techniques. "
ABSTRACT: Risk stratification in cardiac surgery significantly impacts outcome. This study seeks to define whether there is an independent association between the preoperative serum level of hemoglobin (Hb), leukocyte count (LEUCO), high sensitivity C-reactive protein (hsCRP), or B-type natriuretic peptide (BNP) and postoperative morbidity and mortality in cardiac surgery. Prospective, analytic cohort study, with 554 adult patients undergoing cardiac surgery in a tertiary cardiovascular hospital and followed up for 12 months. The cohort was distributed according to preoperative values of Hb, LEUCO, hsCRP, and BNP in independent quintiles for each of these variables. After adjustment for all covariates, a significant association was found between elevated preoperative BNP and the occurrence of low postoperative cardiac output (OR 3.46, 95% CI 1.53--7.80, p = 0.003) or postoperative atrial fibrillation (OR 3.8, 95% CI 1.45--10.38). For the combined outcome (death/acute coronary syndrome/rehospitalization within 12 months), we observed an OR of 1.93 (95% CI 1.00--3.74). An interaction was found between BNP level and the presence or absence of diabetes mellitus. The OR for non-diabetics was 1.26 (95% CI 0.61--2.60) and for diabetics was 18.82 (95% CI 16.2--20.5). Preoperative Hb was also significantly and independently associated with the occurrence of postoperative low cardiac output (OR 0.33, 95% CI 0.13--0.81, p = 0.016). Both Hb and BNP were significantly associated with the lengths of intensive care unit and hospital stays and the number of transfused red blood cells (p < 0.002). Inflammatory markers, although associated with adverse outcomes, lost statistical significance when adjusted for covariates. High preoperative BNP or low Hb shows an association of independent risk with postoperative outcomes, and their measurement could help to stratify surgical risk. The ability to predict the onset of atrial fibrillation or postoperative low cardiac output has important clinical implications. Our results open the possibility of designing studies that incorporate BNP measurement as a routine part of preoperative evaluation, and this strategy could improve upon the standard evaluation in terms of reducing adverse postoperative events.Journal of Cardiothoracic Surgery 07/2013; 8(1):170. DOI:10.1186/1749-8090-8-170 · 1.03 Impact Factor
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- "Atrial fibrillation (AF) is the most common arrhythmic complication after cardiac surgery, with an incidence of approximately 20% to 50% that has not changed despite improvements in anesthesia, surgical techniques, and drug therapy . This is probably due to co-morbidities including older age, left ventricular dysfunction, chronic pulmonary disease, and renal insufficiency, which are also contributors to postoperative AF [2,3]. AF has also been associated with a complicated postoperative course, increased incidence of stroke, increased intensive care unit and total hospital stays, and increased health care costs [2-5]. "
ABSTRACT: Background Landiolol hydrochloride is a new β-adrenergic blocker with a pharmacological profile that suggests it can be administered safely to patients who have sinus tachycardia or tachyarrhythmia and who require heart rate reduction. This study aimed to investigate whether intraoperative administration of landiolol could reduce the incidence of atrial fibrillation (AF) after cardiac surgery. Methods Of the 200 consecutive patients whose records could be retrieved between October 2006 and September 2007, we retrospectively reviewed a total of 105 patients who met the inclusion criteria: no previous permanent/persistent AF, no permanent pacemaker, no renal insufficiency requiring dialysis, and no reactive airway disease, etc. Landiolol infusion was started after surgery had commenced, at an infusion rate of 1 μg/kg/min, titrated upward in 3–5 μg/kg/min increments. The patients were divided into 2 groups: those who received intraoperative β-blocker therapy with landiolol (landiolol group) and those who did not receive any β-blockers during surgery (control group). An unpaired t test and Fisher’s exact test were used to compare between-group differences in mean values and categorical data, respectively. Results Seventeen of the 105 patients (16.2%) developed postoperative atrial fibrillation: 5/57 (8.8%) in the landiolol group and 12/48 (25%) in the control group. There was a significant difference between the two groups (P=0.03). The incidence of AF after valve surgery and off-pump coronary artery bypass grafting was lower in the landiolol group, although the difference between the groups was not statistically significant. Conclusions Our retrospective review demonstrated a marked reduction of postoperative AF in those who received landiolol intraoperatively. A prospective study of intraoperative landiolol for preventing postoperative atrial fibrillation is warranted.Journal of Cardiothoracic Surgery 01/2013; 8(1):19. DOI:10.1186/1749-8090-8-19 · 1.03 Impact Factor