Perioperative serum troponin I levels are associated with higher risk for atrial fibrillation in patients undergoing coronary artery bypass graft surgery

Perioperative Cardiac Troponin T and Risk of Postoperative Atrial Fibrillation in Coronary Artery Bypass Graft Surgery

BACKGROUND

Postoperative atrial fibrillation (AF) is a common complication after cardiac surgery. We investigated whether perioperative cardiac troponin T (cTnT) is associated with the risk of AF after coronary artery bypass grafting (CABG).

METHODS

Two thousand four hundred twenty-one patients with isolated CABG were studied. High sensitivity cTnT (hs-cTnT) was assessed before and then at 80 hour and 24 hour after the operation. Logistic regression models were applied to investigate the association of perioperative hs-cTnT with postoperative AF. The ROC curve analysis was applied to determine the optimal cutoff values.

RESULTS

Postoperative AF was occurred in 356 (14.7%) patients. Age (adjusted odds ratio [ORs] 1.087-1.090), male gender (OR 1.390), left atrium size (ORs 1.055-1.111), on-pump coronary bypass (OR 1.561), and application of intra-aortic balloon pump (ORs 2.890-2.966) were independently associated with AF. Preoperative hs-cTnT was associated with AF in patients with off-pump coronary bypass (ORs 1.997-2.375). However, the area under the curve for preoperative hs-cTnT was 0.625 in this group. On-pump coronary bypass had major influence on postoperative hs-cTnT levels regardless of the occurrence of AF.

CONCLUSIONS

Preoperative hs-cTnT level is associated with the risk of AF after isolated CABG in patients undergoing off-pump coronary bypass, but the accuracy of this biomarker is yet inadequate. Postoperative levels of hs-cTnT have no predictive value considering large influence by the surgical technique and the cardiac surgery itself. Therefore, perioperative hs-cTnT is not a clinically useful biomarker for predicting AF following CABG.

Role of Cardiac Biomarkers in Cancer Patients

Simple Summary

Cardiac biomarkers have proved increasingly useful in the various branches of cardiology, not sparing the field of cardio-oncology. With specific reference to the latter subject, they have been investigated as predictors and/or diagnostic and monitoring tools, as well as prognostic factors, with the purpose of allowing the early prevention of many cardiovascular complications related to the direct action of some cancer types or related to the toxicity of its treatments. However, despite this great potential and excellent cost-effectiveness, their usefulness in some areas still seems to be limited due to lack of sufficient specificity or sensitivity. In fact, in clinical practice, while their use is nowadays standard in some circumstances, evidence does not yet support their routine use in other cases.

Abstract

In patients with cancer—and especially some specific subtypes—the heart can be pathologically affected due to the direct action of the tumor or its secretion products or due to the toxicity of some oncological treatments. Cardiac biomarkers have been investigated as inexpensive and easily accessible tools for prediction, early diagnosis, monitoring, or prognosis of various forms of cancer-related cardiac diseases. However, their clinical usefulness was not always clearly demonstrated in every area of cardioncology. For the identification of anthracycline related cardiotoxicity in the very early stages troponins proved to be more efficient detectors than imaging methods. Nevertheless, the lack of a standardized dosage methodology and of cardiotoxicity specific thresholds, do not yet allow to outline the precise way to employ them in clinical routine and to incorporate them into appropriate diagnostic or managing algorithms. Cardiac biomarkers proved also effective in patients with primary cardiac amyloidosis, in which both troponins and natriuretic peptides were able to predict adverse outcome, and carcinoid heart disease, where a precise diagnostic cut-off for N-terminal prohormone of brain natriuretic peptide (NT-proBNP) was identified to screen patients with valvular involvement. Likewise, NT-proBNP proved to be an excellent predictor of postoperative atrial fibrillation (POAF). On the contrary, evidence is still not sufficient to promote the routine use of cardiac biomarkers to early diagnose myocarditis due to immune check points inhibitors (ICIs), radiotherapy induced cardiotoxicity and cardiac complications related to androgenetic deprivation. In this review we present all the evidence gathered so far regarding the usefulness and limitations of these relatively inexpensive diagnostic tools in the field of cardio-oncology.

Atrial Fibrillation after Lung Cancer Surgery: Prediction, Prevention and Anticoagulation Management

Simple Summary

Atrial fibrillation that occurs after surgery raises further questions with respect to spontaneous atrial fibrillation, being an event unquestionably related to the surgical act itself and always quite self-limiting. The purpose of this review is to present the knowledge gained so far, including the most recent findings, regarding this peculiar form of arrhythmia. Its prognostic impact and the possibility of predicting and preventing it were the subject of our analysis, as well as the similarities and differences with spontaneous atrial fibrillation in relation to anticoagulation. Where possible, the search for evidence has focused on studies involving lung cancer patients undergoing thoracic surgery, highlighting any differences with cardiac surgery.

Abstract

Atrial fibrillation (AF) is a common complication of the early postoperative period of various types of surgery, including that for lung cancer. Although induced by the homeostatic alterations related to surgery, there is evidence that it is not a mere stand-alone transitory event, but it represents a relevant complication of surgery, bearing considerable prognostic consequences. Different methods have therefore been explored to predict the occurrence of postoperative atrial fibrillation (POAF) and prevent it. In particular, the age among clinical factors, and N-terminal prohormone of brain natriuretic peptide (NT-proBNP), as a marker, have proven to be good predictors, and the use of beta-blockers or amiodarone in primary prevention seems to reduce its incidence significantly. There is growing evidence that POAF significantly increases the risk of stroke and global mortality in the long term; therefore, it should be managed in the same way as spontaneous atrial fibrillation. In this review, we will present the strongest evidence found so far and the most recent findings regarding the management of POAF, with a special focus on patients undergoing thoracic surgery for lung cancer.

Incidence and risk factors for new-onset atrial fibrillation following coronary artery bypass grafting: A systematic review and meta-analysis

OBJECTIVES

To estimate the incidence of new-onset post-operative atrial fibrillation after isolated coronary artery bypass surgery and summarise the evidence on risk factors that predispose people to developing the complication.

STUDY DESIGN/METHODS

A systematic review was conducted to identify studies from the CINAHL, MEDLINE and Cochrane databases. A title and abstract review was conducted by one reviewer. Full text review and quality assessment processes were conducted by two reviewers. Incidence data was combined in meta-analysis using the 'metaprop' routine in Stata and risk factor data were synthesised in narrative and table format.

RESULTS

Ten studies, including 6173 participants, were included in the review. The estimated pooled incidence of post-operative atrial fibrillation was 25% (CI 0.19-0.30). In a secondary meta-analysis including studies that only included first time bypass surgery recipients the estimated pooled incidence was 26% (CI 0.14-0.41). Due to high levels of heterogeneity these results should be interpreted with caution. Risk factors with the strongest associations to post-operative atrial fibrillation were chronic obstructive pulmonary disease, decreased partial pressure of oxygen on air, congestive heart failure, right coronary artery disease, male gender, prolonged cross clamp time and port-operative inotropic exposure.

CONCLUSION

Further prospective studies are needed to strengthen the current evidence base.

Prognostic indicators of new onset atrial fibrillation in patients with acute coronary syndrome

Background

This study aims to estimate prognostic indicators of new onset atrial fibrillation (AF) in patients with acute coronary syndrome (ACS) through 3 to 5 years of follow‐up.

Hypothesis

For patients with ACS, some prognostic indicators can be used to predict new onset AF.

Methods

The Improving Care for Cardiovascular Disease in China‐ACS (CCC‐ACS) program was launched in 2014 by a collaborative initiative of the American Heart Association and Chinese Society of Cardiology. We enrolled 866 patients with ACS in a telephone follow‐up program. We inquired about each patient's general health and invited each patient to our hospital for further consultation. We also performed ambulatory electrocardiography and other relevant examinations.

Results

A total of 743 ACS patients were included in the study. After 3 to 5 years, 50 (0.67%) patients developed AF. In multivariable Cox models adjusting for AF risk factors in ACS patients, we found that NT‐proBNP [hazard ratio (HR) 2.625, 1.654‐4.166, P < .05], creatine kinase‐MB (CK‐MB) (HR 4.279, 1.887‐9.703, P < .05), and left ventricular ejection fraction (LVEF) (HR 0.01, 0.001‐0.352, P < .05) were significantly associated with AF receiver operating characteristic (ROC) curves were used to determine a cutoff level for AF screening. NT‐proBNP using a cutoff of 1705 ng/L resulted in a sensitivity of 58% and a specificity of 89.8%. CK‐MB using a cutoff of 142.5 ng/L resulted in a sensitivity of 73.3% and a specificity of 58.3%.

Conclusion

For patients with ACS, NT‐proBNP, CK‐MB, and LVEF have a considerable prognostic value for predicting whether AF would be detected during follow‐up.

Biomarkers of Atrial Fibrillation: Which One Is a True Marker?

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmias and associated with the risk of stroke and death. Continuous development of the diagnostic tool and prognostic stratification may lead to optimal management of AF. The use of biomarkers in the management of AF has been grown as an interesting topic. However, the AF biomarkers are not yet well established in the major guidelines. Among these biomarkers, a lot of data show troponin and brain natriuretic peptides are promising for the prediction of future events. The troponin elevation in AF patients may not necessarily be diagnosed as myocardial infarction or significant coronary artery stenosis, and brain natriuretic peptide elevation may not necessarily confirm heart failure. Troponin T and troponin I may predict postoperative AF. Furthermore, troponin and brain natriuretic peptide gave better prognostic performance when compared with the risk score available today.

Clinical Applications of Biomarkers in Atrial Fibrillation

While biomarkers have greatly impacted the diagnosis and management of myocardial infarction and heart failure, the use of biomarkers has been slow to permeate management of atrial fibrillation. Guideline recommendations on the use of biomarkers in atrial fibrillation were virtually nonexistent until the 2016 European Society of Cardiology guidelines on atrial fibrillation offered a class IIb recommendation to consider using biomarkers such as high-sensitivity troponin and natriuretic peptide to further refine stroke and bleeding risk in atrial fibrillation patients. Biomarker levels have been associated with incident atrial fibrillation, postoperative atrial fibrillation, acute atrial fibrillation, diagnosis of myocardial infarction and heart failure in atrial fibrillation, and prognosis in atrial fibrillation. This review will offer an in-depth survey of current evidence on the use of biomarkers in atrial fibrillation and propose clinical algorithms to aid the internist in using biomarkers in atrial fibrillation management.

Preoperative Antihypertensive Medication in Relation to Postoperative Atrial Fibrillation in Patients Undergoing Cardiac Surgery: A Meta-Analysis

Background. We undertake a systematic review and meta-analysis to evaluate the effect of preoperative hypertension and preoperative antihypertensive medication to postoperative atrial fibrillation (POAF) in patients undergoing cardiac surgery. Methods. We searched PubMed, Embase, and Cochrane Library (from inception to March 2016) for eligible studies. The outcomes were the effects of preoperative hypertension, preoperative calcium antagonists regimen, preoperative ACE inhibitors regimen, and preoperative beta blocking agents regimen with POAF. We calculated pooled risk ratios (OR) and 95% CIs using random- or fixed-effects models. Results. Twenty-five trials involving 130087 patients were listed. Meta-analysis showed that the number of preoperative hypertension patients in POAF group was significantly higher (P < 0.05), while we found that there are no significant differences between two groups in Asia patients by subgroup analysis, which is in contrast to other outcomes. Compared with the Non-POAF group, the number of patients who used calcium antagonists and ACE inhibitors preoperatively in POAF group was significantly higher (P < 0.05). And we found that there were no significant differences between two groups of preoperative beta blocking agents used (P = 0.08). Conclusions. Preoperative hypertension and preoperative antihypertensive medication in patients undergoing cardiac operations seem to be associated with higher risk of POAF.

SYNTAX score predicts postoperative atrial fibrillation in patients undergoing on-pump isolated coronary artery bypass grafting surgery

Objective:

Atrial fibrillation (AF) is the most common arrhythmia following coronary artery by-pass graft surgery (CABG). The value of SYNTAX score to predict postoperative atrial fibrillation (PoAF) has not been clearly addressed. We aimed to evaluate this relationship in patients undergoing isolated CABG.

Methods:

This study was designed as a single-center, non-randomized, observational, prospective study. Ninety-four patients undergoing isolated on-pump CABG, who had sinus rhythm and were older than 18 years, were enrolled. Demographic characteristics of the patients were recorded; SYNTAX score was calculated preoperatively for each patient. The univariate and multivariate logistic regression analysis were used to determine for predictors of PoAF.

Results:

The median SYNTAX score of the enrolled patients was 21, (56–5). PoAF was observed in 31 (33.3%) patients. Univariate logistic regression showed that age, chronic obstructive pulmonary disease (COPD), red blood cell distribution width (RDW), urea, initial troponin I, peak postoperative troponin I, interventricular septum, left atrial diameter, and SYNTAX score were significantly associated with the frequency of PoAF following CABG. An independent association was identified with age [b 0.088, p:0.023, OR: 1.092, 95% CI (1.012–1.179)], COPD [(b: 2.222, p:0.003, OR: 9.228, 95% CI (2.150–39.602)], and SYNTAX score [(b: 0.130, p:0.002, OR: 1.139, 95% CI (1.050–1.235)].

Conclusion:

This study showed that a higher SYNTAX score was related to more frequent PoAF in patients undergoing isolated on-pump CABG.

Remote ischemic preconditioning and incidence of postoperative atrial fibrillation

OBJECTIVES

Although remote ischemic preconditioning (RIPC) has shown favorable effects on ischemia-reperfusion injury, much remains unknown of its mechanisms and clinical significance. We hypothesized that RIPC would reduce the incidence of postoperative atrial fibrillation (POAF) following coronary artery bypass graft (CABG) surgery. In addition, we investigated whether RIPC could induce alterations of circulating microRNA in blood plasma.

DESIGN

This is a single-center, double-blind, randomized controlled trial. 92 adult patients referred for first-time isolated CABG surgery were randomly assigned to either RIPC (n = 45) or control (n = 47). The RIPC-stimulus comprised three 5-min cycles of upper arm ischemia, induced by inflating a blood pressure cuff to 200 mmHg, with an intervening 5 min reperfusion. Heart rhythm was assessed by telemetry. MicroRNA expression was assessed in plasma by real-time polymerase chain reaction.

RESULTS

Of the 92 patients included in the study, 27 patients developed POAF (29%). 17 of these patients belonged to the RIPC group (38%), and 10 to the control group (21%). There were no significant alterations of microRNA expression.

CONCLUSIONS

We did not observe a reduced incidence of POAF by RIPC before CABG surgery. Larger multi-center studies may be necessary to further clarify this issue.

Troponin-I is a predictor of a delayed diagnosis of atrial fibrillation in acute ischemic stroke and transient ischemic attack

BACKGROUND

Prolonged cardiac monitoring detects higher rates of atrial fibrillation (AF) in ischemic stroke and transient ischemic attack (TIA) but is costly and has practical implications. The use of admission troponin-I (TnI) level to identify patients at high risk of delayed AF detection was investigated.

METHODS

Consecutive ischemic stroke and TIA cases presenting to our institute over a 13-month period were identified from the Irish Stroke and TIA Register. Electronic databases and case notes were examined. "Delayed" AF was diagnosed after a sinus rhythm admission electrocardiogram and no documented history. Group comparisons were made by AF status. The association between TnI and AF was investigated using a multivariate regression model.

RESULTS

A total of 185 cases (130 ischemic stroke) were analyzed. Mean age (standard deviation) was 73.3 (13.9) years, 47% female. Sixty-two cases (33.5%) had AF. The first documented presentation of AF was found in 21 cases, on admission electrocardiogram (n = 11) or inpatient telemetry (delayed, n = 10). TnI was higher in those with delayed AF than in those without AF (W = 194; P = .036). A higher proportion of those with an elevated TnI (30%) than those with a normal TnI (6.1%) had delayed diagnosis of AF (χ(2) = 6.41, P = .011). Having an abnormal TnI was a significant independent predictor of delayed AF detection (odds ratio, 5.8; P = .037).

CONCLUSIONS

TnI elevation is associated with a higher likelihood of subsequent AF diagnosis. Identification of these higher risk stroke and TIA cases for more intensive cardiac monitoring may improve stroke secondary prevention practices.

Relation between soluble ST2, growth differentiation factor-15, and high-sensitivity troponin I and incident atrial fibrillation

BACKGROUND

We investigated whether circulating concentrations of soluble ST2, growth differentiation factor-15 (GDF-15), and high-sensitivity troponin I (hsTnI) are associated with incident atrial fibrillation (AF) and whether these biomarkers improve current risk prediction models including AF risk factors, B-type natriuretic peptide (BNP), and C-reactive protein (CRP).

METHODS

We studied the relation between soluble ST2, GDF-15, and hsTnI and development of AF in Framingham Heart Study participants without prevalent AF. We used Cox proportional hazard regression analysis to examine the relation of incident AF during a 10-year follow-up period with each biomarker. We adjusted for standard AF clinical risk factors, BNP, and CRP.

RESULTS

The mean age of the 3,217 participants was 59 ± 10 years, and 54% were women. During a 10-year follow-up, 242 participants developed AF. In age- and sex-adjusted models, GDF-15 and hsTnI were associated with risk of incident AF; however, after including the AF risk factors and BNP and CRP, only hsTnI was significantly associated with AF (hazard ratio per 1 SD of loge hsTnI, 1.12, 95% CI 1.00-1.26, P = .045). The c statistic of the base model including AF risk factors, BNP, and CRP was 0.803 (95% CI 0.777-0.830) and did not improve by adding individual or all 3 biomarkers. None of the discrimination and reclassification statistics were significant compared with the base model.

CONCLUSION

In a community-based cohort, circulating hsTnI concentrations were associated with incident AF. None of the novel biomarkers evaluated improved AF risk discrimination or reclassification beyond standard clinical AF risk factors and biomarkers.

Atrial fibrillation after isolated coronary surgery. Incidence, long term effects and relation with operative technique

INTRODUCTION

Postoperative atrial fibrillation after isolated coronary revascularization has been associated with increased morbidity and mortality. Aim of present investigation was to evaluate incidence of postoperative atrial fibrillation and its prognostic role in patients undergoing isolated coronary artery by-pass and disclose possible differences between off-pump and cardiopulmonary assisted revascularization.

METHODS

Prospective cohort study of 229 patients undergoing isolated coronary artery by-pass at a tertiary heart surgery Centre. Off-pump treated patients were significantly older (70.5 vs 64.9 years, p<0.001). No other baseline differences were found. Patients who developed postoperative atrial fibrillation were followed up for an average period of 2 years.

RESULTS

Post-operative occurred in 56/229 (24.1% after cardiopulmonary and 24.6% after off-pump coronary artery by-pass). Left atrium diameter was the only independent predictive factor (odds ratio =1.15, 95% confidence interval 1.02-1.30, p<0.001). All patients with postoperative atrial fibrillation were treated and discharged in sinus rhythm, in 6/56 recurred, only in one persisted. One patient died during follow up. No stroke was recorded.

CONCLUSIONS

After isolated surgical revascularization, atrial fibrillation occurred in 24% without differences related to operative technique. Recurrence of atrial fibrillation occurred in 6/56 patients (10.7%) however only in 1 persisted. Early and late mortality did not show relation with post-operative atrial fibrillation probably due to immediate treatment with recovery of sinus rhythm before discharge.

Levosimendan Use Decreases Atrial Fibrillation in Patients after Coronary Artery Bypass Grafting: A Pilot Study

Background: Atrial fibrillation (AF) often occurs after coronary artery bypass grafting (CABG) and can result in increased morbidity and mortality due to complications. In the present study, our goal was to investigate whether the use of levosimendan can reduce the frequency of AF after coronary artery bypass grafting in patients with poor left ventricle function. Material and Methods: To investigate the effectiveness of levosimendan in the prophylaxis of AF, we conducted a prospective, randomized, placebo-controlled clinical study on 200 consecutive patients in whom we performed elective CABG operations. Baseline characteristics were similar in both groups. A control group of 100 patients were treated with placebo (500 mL saline solution), whereas the levosimendan group (n = 100 patients) was treated with levosimendan. High-sensitivity C-reactive protein, cardiac troponin, and creatine kinase–MB levels were measured before surgery and 5 days postoperatively. Results: AF occurred in 12% of the levosimendan group and 36% of the control group. The occurrence of AF was significantly lower in the levosimendan group (P < 0.05). The duration of AF in the levosimendan group was significantly shorter than that in the control group (4.83 ± 1.12 and 6.50 ± 1.55 hours, respectively; P = 0.028). Our research showed that C-reactive protein was higher postoperatively in the control group than in the levosimendan group (P < 0.05). Conclusions: The incidence of postoperative AF in the levosimendan group was reduced significantly in patients with poor left ventricle function after CABG operations.

Application of an automatic adaptive filter for Heart Rate Variability analysis

The presence of artifacts and noise effects in temporal series can seriously hinder the analysis of Heart Rate Variability (HRV). The tachograms should be carefully edited to avoid erroneous interpretations. The physician should carefully analyze the tachogram in order to detect points that might be associated with unlikely biophysical behavior and manually eliminate them from the data series. However, this is a time-consuming procedure. To facilitate the pre-analysis of the tachogram, this study uses a method of data filtering based on an adaptive filter which is quickly able to analyze a large amount of data. The method was applied to 229 time series from a database of patients with different clinical conditions: premature newborns, full-term newborns, healthy young adults, adults submitted to a very-low-calorie diet, and adults under preoperative evaluation for coronary artery bypass grafting. This proposed method is compared to the demanding conventional method, wherein the corrections of occasional ectopic beats and artifacts are usually manually executed by a specialist. To confirm the reliability of the results obtained, correlation coefficients were calculated, using both automatic and manual methods of ltering for each HRV index selected. A high correlation between the results was found, with highly significant p values, for all cases, except for some parameters analyzed in the premature newborns group, an issue that is thoroughly discussed. The authors concluded that the proposed adaptive filtering method helps to efficiently handle the task of editing temporal series for HRV analysis.

Postoperative Atrial Fibrillation: Year 2011 Review of Predictive and Preventative Factors of Atrial Fibrillation Post Cardiac Surgery

Background: Post cardiac surgery atrial fibrillation is common after cardiac surgery. Despite the advances in medical and surgical treatment, its incidence remains high and unchanged for decades. The aim of this review was to summarize studies published in 2011 on identifying factors, prevention strategies, treatment and effect of post operative atrial fibrillation (POAF) on the outcome after cardiac surgery. Methods: A review was performed on Medline, Embase and Chocrane on all of the English-language, peer-reviewed published clinical studies on POAF; studies investigating the mechanism of developing POAF, prevention, treatment and outcome were all included and analyzed. Case reports, studies on persistent/preoperative atrial fibrillation (AF), POAF after cardiac transplant, congenital cases and nonclinical studies were all excluded. We have also valuated these studies based on the type of the study, their originality, impact factor of the journal and their limitations. Results: Overall 62 studies were reviewed and analyzed; 26 on POAF predictive factors, 31 on preventative strategies and 6 on the outcome of POAF. Of these studies only two were original and the remaining were either performed in AF in general population (n=10) or had been studied and reported several times before in cardiac surgery (n=50). The average impact factor of the journals that POAF was published in was only 2.8 ranging between 0.5 and 14.5. Conclusion: Post cardiac surgery atrial fibrillation is a multi-factorial and complex condition. Cardiac surgery may be a risk factor for developing POAF in patients already susceptible to this condition and may not be a complication of cardiac surgery. Future studies should mainly focus on histological changes in the conductive tissue of atrium and related treatment strategies rather than predictive factors of POAF and more funding should be made available to study this condition from new and entirely different perspectives.