Prevalence of Post-Operative Atrial Fibrillation Following Cardiac Surgery Among Asian Population and Preferred Treatment Modalities: A Systemic Review

Background: Postoperative atrial fibrillation (POAF) is a common complication following cardiac surgery, with reported incidences varying widely. Despite numerous studies, the true prevalence and optimal management strategies remain unclear. This systematic review aims to investigate the prevalence and management techniques of POAF followed in the Asian population post-cardiac surgery. Methods: A comprehensive search was conducted using PRISMA criteria across multiple databases. Cohort studies and randomized controlled trials published between 2000 and 2023 were included. Data on study characteristics, prevalence, and treatment modalities were extracted and assessed for quality using standardized tools. Results: Out of 1849 identified studies, 23 met the eligibility criteria, all conducted in Asian countries. The prevalence of POAF ranged from 10 % to 58 % among cardiac surgery patients in individual studies, translating to a calculated mean value of 24.46 % POAF cases in all accumulated eligible studies for prevalence in the Asian population, which is high in comparison to the very few studies taken in the review and its population under study. The prevalence of POAF in the Asian population was calculated to be 20.95%. Various risk factors including age, comorbidities, and surgical techniques were associated with POAF development.

characteristics were evaluated to compare prevalence rates, treatment modalities, and outcomes of POAF among Asian populations undergoing cardiac surgery.

Participant types
The systematic review included studies focus ing on participants who underwent cardiac surgery, particularly within Asian populations.Studies encompassed diverse demographics, including various age groups, genders, and comorbidities such as hypertension, obesity, and diabetes mellitus.Participants ranged from those with no history of cardiac disease to those with complex cardiac conditions requiring surgical intervention.Notably, the review examined both on-pump and off-pump coronary artery bypass grafting (CABG) procedures, encompassing a broad spectrum of patients undergoing cardiac surgery in Asian countries.

Intervention types and controls
The review assessed various intervention types and controls aimed at managing postoperative atrial fibrillation (POAF) following cardiac surgery.Interventions included pharmacological treatments such as antiarrhythmic medications, anticoagulation therapy, and dexmedetomidine administration.Additionally, lifestyle modifications and targeted interventions based on identified risk factors were considered.Control groups encompassed standard postoperative care protocols without specific interventions for POAF prevention.
Studies compared the efficacy and safety of different interventions, often employing randomized controlled trials (RCTs) and cohort studies to evaluate outcomes.

Outcomes measures
The primary outcome measures ofthe systematic review focused on examining the incidence, consequences, and treatment outcomes of POAF following cardiac surgery, particularly among Asian populations.Keysecondary outcome measures included comparative studies of various therapy methods used to manage POAF.Outcome assessments encompassed the prevalence of POAF, recurrence rates, mortality, stroke incidence, and the efficacy of different treatment modalities.Additionally, the review evaluated the impact of individual risk factors, intervention strategies, and patient demographics on POAF outcomes to inform tailored management approaches.

Literature searches and data selection
Four investigators independently searched Pubmed, Google Scholar, Embase, and Cochrane; the remaining members resolved the results."Post-operative atrial fibrillation following cardiac surgery" was the search keyword we used in our study.The titles and abstracts of the papers were used to initially filter them; the screened articles were then chosen using the inclusion and exclusion criteria.Four investigators worked independently on this process, with the other three investigators resolving any differences.We can further narrow them by adding our selection criteria to an AI-powered program named "Rayyan" after importing all of the articles.

Data extraction
Three review authors independently gathered pertinent study features and outcomes from the included studies.The following data were taken from each study: study kind, study period, and year of publication.

Quality/risk of bias assessment of included studies
The findings of all the research taken into consideration in this review could be analyzed since the two reviewers used a thematic approach to synthesize and filter the results of the publications included.The reviewers looked at the titles and abstracts on their own.Related research' whole texts were located and examined.Relevant information was taken out of the research, and using the proper quality evaluation instruments, the risk of bias was evaluated.Two reviewers examined the rob evaluation on their own.Using the Critical Appraisal Skills Programme, the included studies' quality and ROB were evaluated (CASP).Following the identification of the research design and reading of the articles, the CASP tool was used to score the articles, which ranged from 0 to 2.

Data analysis
Data analysis involved a comprehensive synthesis of findings from the included studies, utilizing both quantitative and qualitative approaches.The review assessed the quality and risk of bias of individual studies using standardized evaluation tools, ensuring robustness and reliability of the findings.Furthermore, sensitivity analyses and subgroup analyses were conducted to explore potential sources of heterogeneity and variability in study outcomes.

Study characteristics
We identified 1849 studies meeting our search criteria.After excluding 82 duplicates, 33 were marked as ineligible by automation tools, 1338 records were removed for other reasons, 396 were evaluated and 23 total studies were included in this review.All 23 studies that were included in this systematic review were studies conducted in Asia.The countries included were Japan (6), Turkey (6), Iran (3), Pakistan (2), India (2), China (1), Russia (1), Korea (1), Israel (1).The sample size was less than 100 in 4 studies, between 100 and 1000 in 15, and more than 1000 in 4. The data was extracted from the articles and all the information was used to compare the various treatment modalities for post-operative atrial fibrillation and its prevalence in Asian countries.

Quality/risk of bias of included studies
The Overall risk of the included studies were found to be low.Table 2 shows the RoB assessments of individual studies.The mean RoB score was calculated to be 20.1.The mean difference of each study was calculated.Konstantino Y(20) was found to have the lowest mean difference of -3.9 and the highest RoB score of 24.The population of the world 2024 is 8118835999.And the prevalence of PoAF in the Asian population was calculated to be 20.95429217%.The mean of the percentages of POAF cases in the included studies was calculated to be 24.46%.

Discussion
In this systematic review we studied the prevalence and comparative study of preferred treatment methods from 23 eligible studies.In the study conducted by Fragão-Marques M regarding gender disparity, POAF has an increased risk in men than in women.[18] AF recurrence within 30 days after discharge from the hospital is higher in CS compared with NCS (10% vs 0%, p =0.03).Kaplan Meier analysis showed a trend towards higher recurrence in NCS compared with CS (HR 2.8; 95% CI 0.78-10.6,log-rank p =0.03).[19] While looking at the long-term effects and cerebrovascular accidents, CVA is more common in in-patients with POAF after CS compared with NCS.AF occurred in 10% of patients on landiolol than the 40% in the control group.[32] On anticoagulant efficacy, apixaban and edoxaban exhibit higher safety and efficacy than rivaroxaban.[17] The majority of the patients who developed POAF presented with a history of hypertension and diabetes mellitus (27.50%), with male predominance (70%) with the mean of variables, age=60.19± 9.3 years, body mass index=28.27± 4.2 kg/m2, CPB time = 156 ± 39.7 min, aortic crossclamp time=100 ± 27.2 min, ejection fraction v(EF) = 47.2 ± 10.7%, heart rate = 117.8± 21 beats per minute and serum lactate levels = 3.7 ± 1.54 mmol/lit.[34] Arslan G's study results suggest that on-pump CABG under CPB is correlated with POAF.[35] Postoperative AF was developed in twenty-five patients (11%).The incidence of POAF was 9.5% and 11.5% in SinaCurcumin™ and placebo groups, respectively.Although the occurrence was lower in the treatment group, no significant differences between the groups were observed in this regard (p=0.62).[20] Patients with POAF have higher CHA2DS2-VASc scores than those without (4.09± 0.90 vs. 2.31 ± 1.21; P < 0.001).The POAF rates after cardiac surgery increased with increasing CHA 2 DS 2 -VASc scores.[21] In the cohort study by Tosello F, out of 176 patients of the subject group, 49(27.8%)had early POAF and this incidence barely declined during mid-term follow-up, with 36(20.4%)affected at this time point.57%were free of AF at any time, whereas 11.9% developed early POAF and maintained it during mid-term follow-up.[24] The ratio of POAF occurrence found in the treatment and control group were 12.07% and 27.59% respectively.Vitamin D treatment was found to reduce the risk of POAF development by 0.24 times (p=0.034).[25] Haghjoo M's study showed us that atrial fibrillation developed after CABG in 156 patients (15.8%)and patients with POAF were generally older (p=0.001) and presented more often comorbidities including congestive cardiac failures (p=0.001)hypertension (p=0.001)peripheral vascular disease (p=0.001)hyperlipidemia (p=0.009)renal failure(p=0.001)and five-year mortality was observed in 23 patients (2.3%), with those with POAF having a higher five-year mortality rate than those without.[26] Multivariate Cox proportional hazards regression analysis revealed that M/H ratio (odds ratio [OR], 51.814; 95% confidence interval [CI], 11.479-233.865;p<0.01) and serum HDL level (OR,1.874;%95 CI, 1.402-2.505;p<0.01) were independent predictors of POAF in patients after CABG surgery.In the receiver operating characteristic curve analysis of the M/H ratio, the area under the curve was found to be 0.844.[28] A study by Selcuk M showed us that the Systemic Inflammatory Index was an independent predictor of PoAF in patients who were operated on for isolated CABG.Multivariate logistic regression analysis revealed that the SII was an independent predictor of PoAF (Odds ratio: 1.002 95% confidence interval: (1.001-1.002),p<0.01).[29] New-onset POAF was independently related to the presence and number of fQRS in patients undergoing CABG surgery.[30] Research by Konstantino Y had 2 groups of patients with and without POAF, approximately half of the patients experienced prior myocardial infarction, and 14% had left ventricular ejection fraction < 40%.[31] In a randomized controlled study by Liu X consisting of the administration of dexmedetomidine, the absolute risk reduction for AF was 22.8 % in patients following cardiac surgery, with a number needed to treat 4.4, suggesting that dexmedetomidine administration during the early postoperative period could prevent one case of AF for every five patients.[38]

Limitations:
This study must be interpreted considering its limitations.Our systematic review identified the best available evidence comparing outcomes of the prevalence of Poaf following cardiac surgery among the Asian population and a comparative study on the preferred treatment modalities.Poaf assessment methods were non-randomized in all studies creating the possibility for biases and confounding.Additionally, the Sample size was less than 100 in 4 studies, between 100 and 1000 in 15, and more than 1000 in 4. The overall risk was found to be low.The mean difference of each study using the ROBIS tool ROB score was calculated.Konstanino Y(20) was found to have the lowest mean difference of -3.9 and the highest RoB score of 24.Postoperative Af was developed in twenty-five patients (11%).Af occurred in 10% of patients on landiolol than the 40% control group.On anticoagulant efficacy apixaban and edoxaban exhibit higher safety and efficacy compared to rivaroxaban.Although the occurrence was lower in the treatment group no significant differences between the groups were observed in this regard (p=0.62).Dexmedetomidine administration during the early postoperative period could prevent one case of af for every five patients.Moreover, the population of the world in 2024 is 8118835999 and the prevalence of Poaf in the Asian population was calculated to be 20.95429217%.The poaf rates after cardiac surgery increased in most studies hence a definite preventive strategy could not be identified instead a tailored intervention specific to the individual is deemed fit.

Figure 1 :
Figure 1: Prisma sheet for study selection By univariate analysis, older age, P-wave abnormality in ECG, presence of mitral regurgitation, larger left atrium (LA), left main coronary artery involvement, failure to graft right coronary artery (RCA), and adrenergic use in ICU were significantly associated with occurrence of post-CABG AF (all P< 0.05).However, in the logistic regression model, age (OR: 1.067, 95%CI: 1.02-1.116,P=0.005), LA dimension (OR: 1.102, 95%CI: 1.017-1.1936,P=0.017), P-wave morphology (OR: 12.07, 95%CI: 3.35-48.22,P=0.0001), failure to graft RCA (OR: 3.57, 95%CI: 1.20-10.64,P=0.022), and postoperative adrenergic use (OR: 0.35, 95%CI: 0.13-0.93,P=0.036) remained independently predictive of postoperative AF.[36] Ak K presented a study where myolysis and increased apoptotic pattern were observed in right atrial myocardium which are significant predictors for the development of postoperative atrial fibrillation.[37]Our study has shown that the prevalence of AF in Asia Pacific countries ranges from 0.49% to 5.4%, with PoAF occurring after 25-50% of cardiac surgeries, with a calculated 20.95429217 % prevalence in the Asian population.Taking into account all this information, the preferred treatment modality may involve a combination of interventions along with individual patient characteristics.Management strategies could include antiarrhythmic medications, anticoagulation therapy, lifestyle modifications and possibly targeted interventions based on identified risk factors.