Prognostic factors of atrial fibrillation following elective coronary artery bypass grafting: the impact of quantified intraoperative myocardial ischemia

Clinical factors associated with arrhythmia and short-term prognosis following mitral valve repair: a retrospective cohort study

BACKGROUND

Postoperative arrhythmia (POA) is one of the common and serious postoperative complications. This retrospective study was conducted to investigate the clinical factors associated with POA and its short-term prognosis following mitral valve repair.

METHODS

A total of 618 patients receiving mitral valve repair between January 2015 and November 2020 in our hospital were included in this retrospective study, including 318 males and 300 females and aged 53.9±9.3 years. The patients were grouped into arrhythmia and non-arrhythmia groups and investigated for risk factors associated with the prognosis of POA using multivariate logistic regression based on their clinical data.

RESULTS

POA was observed in 314 (50.8%) patients and atrial fibrillation (AF) was the most frequent (43.3%) type of POA. Compared with non-arrhythmia patients, arrhythmia patients had significantly longer time to use vasoactive drug use, longer intensive care unit (ICU) stay and longer hospital stay. In addition, the incidence of postoperative heart failure was significantly higher (P<0.05). Logistic regression analysis showed that preoperative arrhythmia [odds ratio (OR) =9.17; 95% confident interval (CI): 4.49-18.10], postoperative pain (OR =4.70; 95% CI: 1.55-6.12) and postoperative hypoxemia (OR =3.25; 95% CI: 1.04-6.28) were independently associated with POA.

CONCLUSIONS

This study demonstrates that the incidence of arrhythmia is relatively high after mitral valve repair and is associated with preoperative arrhythmia, postoperative pain and postoperative hypoxemia.

Reduced Left Ventricular Global Longitudinal Strain Predicts Prolonged Hospitalization: A Cohort Analysis of Patients Having Aortic Valve Replacement Surgery

BACKGROUND

Left ventricular ejection fraction (LVEF) is often preserved in patients with aortic stenosis and thus cannot distinguish between normal myocardial contractile function and subclinical dysfunction. Global longitudinal strain and strain rate (SR), which measure myocardial deformation, are robust indicators of myocardial function and can detect subtle myocardial dysfunction that is not apparent with conventional echocardiographic measures. Strain and SR may better predict postoperative outcomes than LVEF. The primary aim of our investigation was to assess the association between global longitudinal strain and serious postoperative outcomes in patients with aortic stenosis having aortic valve replacement. Secondarily, we also assessed the associations between global longitudinal SR and LVEF and the outcomes.

METHODS

In this post hoc analysis of data from a randomized clinical trial (NCT01187329), we examined the association between measures of myocardial function and the following outcomes: (1) need for postoperative inotropic/vasopressor support; (2) prolonged hospitalization (>7 days); and (3) postoperative atrial fibrillation. Standardized transesophageal echocardiographic examinations were performed after anesthetic induction. Myocardial deformation was measured using speckle-tracking echocardiography. Multivariable logistic regression was used to assess associations between measures of myocardial function and outcomes, adjusted for potential confounding factors. The predictive ability of global longitudinal strain, SR, and LVEF was assessed as area under receiver operating characteristics curves (AUCs).

RESULTS

Of 100 patients enrolled in the clinical trial, 86 patients with aortic stenosis had acceptable images for global longitudinal strain analysis. Primarily, worse intraoperative global longitudinal strain was associated with prolonged hospitalization (odds ratio [98.3% confidence interval], 1.22 [1.01-1.47] per 1% decrease [absolute value] in strain; P = .012), but not with other outcomes. Secondarily, worse global longitudinal SR was associated with prolonged hospitalization (odds ratio [99.7% confidence interval], 1.68 [1.01-2.79] per 0.1 second(-1) decrease [absolute value] in SR; P = .003), but not other outcomes. LVEF was not associated with any outcomes. Global longitudinal SR was the best predictor for prolonged hospitalization (AUC, 0.72), followed by global longitudinal strain (AUC, 0.67) and LVEF (AUC, 0.62).

CONCLUSIONS

Global longitudinal strain and SR are useful predictors of prolonged hospitalization in patients with aortic stenosis having an aortic valve replacement.

Can dexmedetomidine reduce atrial fibrillation after cardiac surgery? A systematic review and meta-analysis

Purpose

Cardiac surgery patients always present with atrial fibrillation (AF) after admission to the intensive care unit, leading to high mortality and lengthy hospitalization. Dexmedetomidine (DEX) is a popular medication used for sedation in the intensive care unit; however, whether it can reduce AF needs to be analyzed.

Materials and methods

Three primary databases, Medline, Embase (Ovid SP) and the Cochrane Central Register of Controlled Trials (CENTRAL), were searched. All English language and randomized control designed clinical publications comparing DEX to control medicines for sedation after elective cardiac surgery were included. Two independent colleagues conducted the data extraction and quality assessments. The subgroup analysis was performed according to the medicine used, age, AF history, and whether previous beta-blocker premedication and cardiopulmonary bypass (CPB) were applied. The overall incidence of AF was analyzed.

Results

A total of 1,295 patients in nine studies met the selection criteria among 2,587 studies screened from the database. After quantitative synthesis, our results revealed that the DEX group was not associated with a decreased incidence of AF compared with the placebo (risk ratio [RR] 0.76, 95% CI 0.37, 1.55, P=0.44) and morphine groups (RR 0.86, 95% CI 0.56, 1.31, P=0.48). Subgroup analysis also indicated that the DEX vs propofol comparison exhibited no difference: 1) for patients of age >60 years (P=0.69) or ≤60 years (P=0.69); 2) under CPB surgery (P=0.45) or without CPB surgery (P=0.88); 3) with beta-blocker premedication (P=0.32) or without beta-blocker premedication (P=0.90); and 4) with AF history (RR 1.07, 95% CI 0.85, 1.36, P=0.57) or without AF history (P=0.30).

Conclusion

This meta-analysis revealed that DEX could not reduce the incidence of AF compared to control medicines following cardiac surgery. DEX may have an increased influence on AF occurrence if patients had a history of AF. However, cautious interpretation should be made due to high clinical heterogeneity.

Does dexmedetomidine have an antiarrhythmic effect on cardiac patients? A meta-analysis of randomized controlled trials

Background

Cardiac surgery patients often experience several types of tachyarrhythmias after admission to the intensive care unit (ICU), which increases mortality and morbidity. Dexmedetomidine (DEX) is a popular medicine used for sedation in the ICU, and its other pharmacological characteristics are gradually being uncovered.

Purpose

To determine whether DEX has an antiarrhythmic effect after cardiac surgery.

Methods

The three primary databases MEDLINE, Embase (OVID SP) and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched, and all English-language and randomized control-designed clinical publications comparing DEX to control medicines for sedation after elective cardiac surgery were included. Two colleagues independently extracted the data and performed other quality assessments. A subgroup analysis was performed according to the different medicines used and whether cardiopulmonary bypass (CPB) was applied. All tachyarrhythmias that occurred in the atria and ventricles were analyzed.

Results

A total of 1295 patients in 9 studies met the selection criteria among 2587 studies that were screened. After quantitative synthesis, our results revealed that the DEX group was associated with a lower incidence of ventricular arrhythmia (VA, OR 0.24, 95% CI 0.09–0.64, I² = 0%, P = 0.005) than the control group. Subgroup analysis did not reveal a significant difference between the DEX and propofol subgroups (OR 0.13, 95% CI 0.03–0.56, I² = 0%, P = 0.007). Additionally, no difference in the incidence of atrial fibrillation (AF) was observed regardless of the different control medicines (OR 0.82, 95% CI 0.60–1.10, I² = 25%, P = 0.19) or whether CPB was applied.

Conclusions

This meta-analysis revealed that DEX has an antiarrhythmic effect that decreases the incidence of VA compared to other drugs used for sedation following cardiac surgery. DEX may not have an effect on AF, but cautious interpretation should be exercised due to high heterogeneity.

Clinical significance and risk factors for new onset and recurring atrial fibrillation following cardiac surgery - a retrospective data analysis

Background

Although mortality after cardiac surgery has significantly decreased in the last decade, patients still experience clinically relevant postoperative complications. Among others, atrial fibrillation (AF) is a common consequence of cardiac surgery, which is associated with prolonged hospitalization and increased mortality.

Methods

We retrospectively analyzed data from patients who underwent coronary artery bypass grafting, valve surgery or a combination of both at the University Hospital Muenster between April 2014 and July 2015. We evaluated the incidence of new onset and intermittent/permanent AF (patients with pre- and postoperative AF). Furthermore, we investigated the impact of postoperative AF on clinical outcomes and evaluated potential risk factors.

Results

In total, 999 patients were included in the analysis. New onset AF occurred in 24.9% of the patients and the incidence of intermittent/permanent AF was 59.5%. Both types of postoperative AF were associated with prolonged ICU length of stay (median increase approx. 2 days) and duration of mechanical ventilation (median increase 1 h). Additionally, new onset AF patients had a higher rate of dialysis and hospital mortality and more positive fluid balance on the day of surgery and postoperative days 1 and 2. In a multiple logistic regression model, advanced age (odds ratio (OR) = 1.448 per decade increase, p < 0.0001), a combination of CABG and valve surgery (OR = 1.711, p = 0.047), higher C-reactive protein (OR = 1.06 per unit increase, p < 0.0001) and creatinine plasma concentration (OR = 1.287 per unit increase, p = 0.032) significantly predicted new onset AF. Higher Horowitz index values were associated with a reduced risk (OR = 0.996 per unit increase, p = 0.012). In a separate model, higher plasma creatinine concentration (OR = 2.125 per unit increase, p = 0.022) was a significant risk factor for intermittent/permanent AF whereas higher plasma phosphate concentration (OR = 0.522 per unit increase, p = 0.003) indicated reduced occurrence of this arrhythmia.

Conclusions

New onset and intermittent/permanent AF are associated with adverse clinical outcomes of elective cardiac surgery patients. Different risk factors implicated in postoperative AF suggest different mechanisms might be involved in its pathogenesis. Customized clinical management protocols seem to be warranted for a higher success rate of prevention and treatment of postoperative AF.

Electronic supplementary material

The online version of this article (10.1186/s12871-017-0455-7) contains supplementary material, which is available to authorized users.

Comparison of Two Central Venous Pressure Control Strategies to Prevent Atrial Fibrillation After Coronary Artery Bypass Grafting

BACKGROUND:

Atrial fibrillation (AF) takes place in 10-40% of patients undergoing coronary artery bypass grafting (CABG), and increases cardiovascular mortality. Enlargement of atrial chambers is associated with increased AF incidence, so patients with higher central venous pressure (CVP) are expected to have larger atrial distension, which increases AF incidence.

OBJECTIVE:

To compare post-CABG AF incidence, following two CVP control strategies.

METHODS:

Interventional, randomized, controlled clinical study. The sample comprised 140 patients undergoing CABG between 2011 and 2015. They were randomized into two groups, G15 and G20, with CVP maintained ≤ 15 cmH2O and ≤ 20 cmH2O, respectively.

RESULTS:

70 patients were included in each group. The AF incidence in G15 was 8.57%, and in G20, 22.86%, with absolute risk reduction of 14.28%, and number needed to treat (NNT) of 7 (p = 0.03). Mortality (G15 = 5.71%; G20 = 11.42%; p = 0.07), hospital length of stay (G15 = 7.14 days; G20 = 8.21 days; p = 0.36), number of grafts (median: G15 = 3, G2 = 2; p = 0.22) and cardiopulmonary bypass use (G15 = 67.10%; G20 = 55.70%; p = 0.22) were statistically similar. Age (p = 0.04) and hospital length of stay (p = 0.001) were significantly higher in patients who developed AF in both groups.

CONCLUSION:

Keeping CVP low in the first 72 post-CABG hours reduces the relative risk of AF, and may be useful to prevent AF after CABG.

FUNDAMENTO:

A fibrilação atrial (FA) ocorre em 10-40% dos pacientes submetidos a cirurgia de revascularização miocárdica (RM), e eleva a mortalidade cardiovascular. Como o aumento dos átrios está associado ao aumento da incidência de FA, espera-se que pacientes com pressão venosa central (PVC) mais alta tenham maior distensão atrial, o que eleva a incidência dessa arritmia.

OBJETIVO:

Comparar a incidência de FA em pós-operatório de RM, seguindo duas estratégias de controle de PVC.

MÉTODOS:

Estudo clínico randomizado controlado intervencionista. A amostra foi composta por 140 pacientes submetidos a RM entre 2011 e 2015. Os pacientes foram randomizados em dois grupos, G15 e G20, mantidos com PVC máxima de 15 cmH2O e 20 cmH2O, respectivamente.

RESULTADOS:

Foram incluídos 70 pacientes em cada grupo. A incidência da arritmia em G15 foi de 8,57% e, no G20, de 22,86%, com redução de risco absoluto de 14,28% e número necessário para tratar (NNT) de 7 (p = 0,03). Mortalidade (G15 = 5,71%; G20 = 11,42%; p = 0,07), tempo de internamento (G15 = 7,14 dias; G20 = 8,21 dias; p = 0,36), número de enxertos (medianas: G15 = 3, G2 = 2; p = 0,22) e uso de circulação extracorpórea (G15 = 67,10%; G20 = 55,70%; p = 0,22) mostraram-se estatisticamente semelhantes. A idade (p = 0,04) e o tempo de internamento (p = 0,001) foram significativamente maiores nos pacientes que desenvolveram FA nos dois grupos.

CONCLUSÃO:

Manter a PVC com valores mais baixos nas primeiras 72h após a cirurgia de RM reduz o risco relativo de FA e pode ser uma ferramenta útil na prevenção da FA após RM.

Usefulness of right ventricular dysfunction to predict new-onset atrial fibrillation following coronary artery bypass grafting

Postoperative atrial fibrillation (AF) is a serious yet common complication after coronary artery bypass grafting (CABG) surgery. Risk factors for postoperative AF have been identified, including echocardiographic parameters, and these are relied on to implement preventative strategies that reduce the incidence of AF. There has yet to be a study examining the impact of echocardiographic right-sided cardiac parameters on the prediction of postoperative AF. Thus, a panel of right-sided cardiac parameters was measured in a cohort of patients undergoing isolated CABG surgery, excluding those who did not have echocardiographic assessment within 30 days before surgery and those with any history of AF. The primary outcome was postoperative AF defined as any episode of AF requiring treatment during the index hospitalization. Postoperative AF occurred in 197 of 768 patients (25.6%); these were older and more likely to have hypertension and chronic kidney disease. After adjustment for clinical and echocardiographic variables, left atrial volume index ≥34 ml/m(2) (odds ratio [OR] 1.98, 95% confidence interval [CI] 1.36 to 2.87), abnormal right ventricular myocardial performance index (OR 1.50, 95% CI 1.01 to 2.24), and advancing age (OR 1.05, 95% CI 1.03 to 1.07) were found to be independent predictors of postoperative AF. In conclusion, right ventricular myocardial performance index is a novel predictor of postoperative AF in patients undergoing isolated CABG surgery and appears to be additive to established risk factors such as age and left atrial volume.

Monoamine oxidase is a major determinant of redox balance in human atrial myocardium and is associated with postoperative atrial fibrillation

Background

Onset of postoperative atrial fibrillation (POAF) is a common and costly complication of heart surgery despite major improvements in surgical technique and quality of patient care. The etiology of POAF, and the ability of clinicians to identify and therapeutically target high‐risk patients, remains elusive.

Methods and Results

Myocardial tissue dissected from right atrial appendage (RAA) was obtained from 244 patients undergoing cardiac surgery. Reactive oxygen species (ROS) generation from multiple sources was assessed in this tissue, along with total glutathione (GSHt) and its related enzymes GSH‐peroxidase (GPx) and GSH‐reductase (GR). Monoamine oxidase (MAO) and NADPH oxidase were observed to generate ROS at rates 10‐fold greater than intact, coupled mitochondria. POAF risk was significantly associated with MAO activity (Quartile 1 [Q1]: adjusted relative risk [ARR]=1.0; Q2: ARR=1.8, 95% confidence interval [CI]=0.84 to 4.0; Q3: ARR=2.1, 95% CI=0.99 to 4.3; Q4: ARR=3.8, 95% CI=1.9 to 7.5; adjusted P_trend=0.009). In contrast, myocardial GSHt was inversely associated with POAF (Quartile 1 [Q1]: adjusted relative risk [ARR]=1.0; Q2: ARR=0.93, 95% confidence interval [CI]=0.60 to 1.4; Q3: ARR=0.62, 95% CI=0.36 to 1.1; Q4: ARR=0.56, 95% CI=0.34 to 0.93; adjusted P_trend=0.014). GPx also was significantly associated with POAF; however, a linear trend for risk was not observed across increasing levels of the enzyme. GR was not associated with POAF risk.

Conclusions

Our results show that MAO is an important determinant of redox balance in human atrial myocardium, and that this enzyme, in addition to GSHt and GPx, is associated with an increased risk for POAF. Further investigation is needed to validate MAO as a predictive biomarker for POAF, and to explore this enzyme's potential role in arrhythmogenesis.

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.