Prophylaxis Of Atrial Fibrillation Research Articles

Abstract 16063: African American's Are Prescribed Direct Oral Anticoagulants at Lower Rate Than White Patient's in an Inpatient Cohort With Diagnosis of Atrial Fibrillation

Introduction: Previous studies have demonstrated racial disparities in the treatment of atrial fibrillation (AF). Potential explanations for disparities in care include cost and insurance coverage issues. This has not been examined in relation to anticoagulation (AC) therapy for thromboembolic prophylaxis of AF in a more contemporary practice using an inpatient cohort. Hypothesis: For hospitalized patients with AF, is there disparity in the rate of prescription of direct oral anticoagulant (DOAC) therapy at discharge for Black compared to White patients? Methods: A single-center retrospective query of all patients hospitalized at a University Hospital with a primary or secondary diagnosis of “AF” in 2022 and a prescription for AC at time of discharge was performed using EPIC. Baseline characteristics and AC prescription were compared between Black and White patients using the χ2 test for categorical variables and t test for continuous variables. Results: There were 275 patients that met the inclusion criteria. Demographics were 38.2% female, 66.5% White, and 14.9% Black (Table). DOAC was prescribed at discharge for 66.1% of White and in 55.0% of Black patients (p=0.01). The distribution of type of AC prescribed at discharge is shown (Figure). Conclusions: There is an ongoing racial disparity in the rate of DOAC prescription in hospitalized patients with AF, despite similar insurance status. Further investigation into underlying reasons for these differences and ways to eliminate disparities is warranted.

DNA Methylation and Telomeres-Their Impact on the Occurrence of Atrial Fibrillation during Cardiac Aging.

Atrial fibrillation (AF) is the most common arrhythmia in humans. AF is characterized by irregular and increased atrial muscle activation. This high-frequency activation obliterates the synchronous work of the atria and ventricles, reducing myocardial performance, which can lead to severe heart failure or stroke. The risk of developing atrial fibrillation depends largely on the patient's history. Cardiovascular diseases are considered aging-related pathologies; therefore, deciphering the role of telomeres and DNA methylation (mDNA), two hallmarks of aging, is likely to contribute to a better understanding and prophylaxis of AF. In honor of Prof. Elizabeth Blackburn's 75th birthday, we dedicate this review to the discovery of telomeres and her contribution to research on aging.

Atrial fibrillation in heart failure patients: An update on renin-angiotensin-aldosterone system pathway blockade as a therapeutic and prevention target.

Heart failure (HF) and atrial fibrillation (AF) are two cardiovascular (CV) entities that affect millions of individuals worldwide and their prevalence is translated into a significant impact on health care systems. The common pathophysiological pathways that these two share have created an important clinical interrelation, as the coexistence of HF and AF is associated with worse prognosis and treatment challenges. Renin-angiotensin-aldosterone system (RAAS), a critical mechanism in blood pressure (BP) control, was proved to be involved in the pathogenesis of both conditions contributing to their further coexistence. Successful control of BP is of great importance to the management of HF, crucial for the prevention of arrhythmiogenic substrates, while RAAS antagonists may possibly affect the development of new-onset AF as well. There are numerous studies that evaluated the effectiveness of RAAS blockade in AF/HF population and despite comparable or modest results, there is a well-established suggestion that RAAS blockers may contribute to a reduction of HF, CV events and recurrence of AF, along with their potential effective role in the new-onset AF prophylaxis. Angiotensin receptor blockers, according to the evidence, are more effective in that direction, followed by angiotensin converting enzyme inhibitors, whereas the data on aldosterone antagonists are not encouraging, yet do have the potential of significant CV disease modificators regardless of their effects on BP.

Mortality on DOACs Versus on Vitamin K Antagonists in Atrial Fibrillation: Analysis of the Hungarian Health Insurance Fund Database

Limited real-world data are available on the survival of patients treated with vitamin K antagonists (VKAs) versus with direct oral anticoagulants (DOACs) for nonvalvular atrial fibrillation (AF). In this nationwide registry, we analyzed the mortality risk of patients with nonvalvular AF taking DOACs versus VKAs, with a special attention to the early treatment period. The Hungarian National Health Insurance Fund (NHIF) database was searched to identify patients treated with VKA or DOAC as a thromboembolic prophylaxis for nonvalvular AF between 2011 and 2016. The overall and the early (0-3, 4-6, and 7-12 months) mortality risks with the 2 types of anticoagulation were compared. A total of 144,394 patients with AF treated with either a VKA (n=129,925) or a DOAC (n=14,469) were enrolled. A 28% improvement in 3-year survival with DOAC treatment compared with VKA treatment was shown. Mortality reduction with DOACs was consistent across different subgroups. However, younger patients (30-59 years old) initiated on DOAC therapy had the greatest RRR (53%) in mortality. Furthermore, DOAC treatment also yielded a benefit of greater magnitude (HR = 0.55; 95% CI, 0.40-0.77, P = 0.001) in the lower (0-1) CHA2DS2-VASc score segment and in those with fewer (0-1) bleeding risk factors (HR = 0.50, CI 0.34-0.73, P = 0.001). The RRR in mortality with DOACs was 33% within the first 3 months, and 6% in the second year. Thromboembolic prophylaxis with DOACs in this study yielded significantly lower mortality compared with VKA treatment in patients with nonvalvular AF. The largest benefit was shown in the early period after treatment initiation, as well as in younger patients, those with a lower CHA2DS2-VASc score, and those with fewer bleeding risk factors.

Prophylaxis of Atrial Fibrillation After Isolated On-pump Coronary Artery Bypass Surgery with Postoperative Intravenous Magnesium Sulfate Supplementation

Prophylaxis of Atrial Fibrillation After Isolated On-pump Coronary Artery Bypass Surgery with Postoperative Intravenous Magnesium Sulfate Supplementation

Risks and benefits of oral anticoagulants for stroke prophylaxis in atrial fibrillation according to body mass index: Nationwide cohort study of primary care records in England.

Direct oral anticoagulants (DOACs) are effective and safe alternatives to warfarin for stroke prophylaxis for atrial fibrillation (AF). Whether this extends to patients at the extremes of body mass index (BMI) is unclear. Using linked primary and secondary data, Jan 1, 2010 to Nov 30, 2018, we included CHA2DS2-VASC score ≥3 in women and ≥2 in men with AF treated with oral anticoagulants (OACs). Outcomes were ischaemic stroke, major bleeding and all-cause mortality by World Health Organisation BMI classification. Patients who received warfarin were propensity score matched (1:1 ratio) with those who received DOACs and the association of time-varying OAC exposure on outcomes quantified using Cox proportional hazards models. We included 29,135 (22,818 warfarin, 6317 DOAC); 585 (2.0%) underweight, 8427 (28.9%) normal weight, 10,705 (36.7%) overweight, 5910 (20.3%) class I obesity and 3508 (12.0%) class II/III obesity. Patients treated with DOACs were older and more comorbid. After 3.7 (SD 2.5) years follow up, there was no difference in risk of ischaemic stroke and major bleeding by BMI category between DOACs and warfarin. Normal weight, overweight and obese class I patients had higher risk of all-cause mortality when treated with DOACs compared with warfarin (HR: 1.45 [95% CI 1.24-1.69], p<0.001; 1.41 [95% CI 1.19-1.66], p<0.001; and 1.90 [95% CI 1.50-2.39], p<0.001), an effect not observed after DOACs became the most common OAC prescription. Amongst underweight patients OAC exposure was associated with greater harm from bleeding than benefit from stroke prevention (benefit to harm ratio, 0.35 [95% CI 0.26-0.44]). In patients with AF in each BMI classification we found no difference in ischaemic stroke and bleeding risk for DOACs compared with warfarin. Underweight patients experienced divergent risk-benefit patterns from oral anticoagulation compared with other BMI categories. None.

Clinician preference instrumental variable analysis of the effectiveness of magnesium supplementation for atrial fibrillation prophylaxis in critical care

Atrial fibrillation is a frequently encountered condition in critical illness and causes adverse effects including haemodynamic decompensation, stroke and prolonged hospital stay. It is a common practice in critical care to supplement serum magnesium for the purpose of preventing episodes of atrial fibrillation. However, no randomised studies support this practice in the non-cardiac surgery critical care population, and the effectiveness of magnesium supplementation is unclear. We sought to investigate the effectiveness of magnesium supplementation in preventing the onset of atrial fibrillation in a mixed critical care population. We conducted a single centre retrospective observational study of adult critical care patients. We utilised a natural experiment design, using the supplementation preference of the bedside critical care nurse as an instrumental variable. Using routinely collected electronic patient data, magnesium supplementation opportunities were defined and linked to the bedside nurse. Nurse preference for administering magnesium was obtained using multilevel modelling. The results were used to define "liberal" and "restrictive" supplementation groups, which were inputted into an instrumental variable regression to obtain an estimate of the effect of magnesium supplementation. 9114 magnesium supplementation opportunities were analysed, representing 2137 critical care admissions for 1914 patients. There was significant variation in magnesium supplementation practices attributable to the individual nurse, after accounting for covariates. The instrumental variable analysis showed magnesium supplementation was associated with a 3% decreased relative risk of experiencing an atrial fibrillation event (95% CI − 0.06 to − 0.004, p = 0.03). This study supports the strategy of routine supplementation, but further work is required to identify optimal serum magnesium targets for atrial fibrillation prophylaxis.

Shared Decision-Making During a Lung Cancer Screening Visit: Is It a Barrier or Does It Bring Value?

The US Preventive Services Task Force has embraced the use of shared decision-making (SDM) as a preferred approach for discussing prevention and early detection activities since 2004.1 Recently, the Centers for Medicare and Medicaid Services have required documentation of SDM for a variety of health care encounters, including lung cancer screening, placement of cardiac defibrillators, and stroke prophylaxis in atrial fibrillation.2 The first use of this standard involved the Centers for Medicare and Medicaid Services decision to cover lung cancer screening (LCS) in 2015.

The possibility of using pharmacological antiarrhythmic therapy and modulated kinesotherapy as a primary prevention of atrial fibrillation in patients with metabolic syndrome and with premature atrial complexes: prospective study

Highlights. The results of primary prevention of atrial fibrillation by using antiarrhythmic drug therapy and modulated kinesitherapy in patients with metabolic syndrome with premature atrial complexes are presented.A significant decrease in the development of the disease was revealed in patients with metabolic syndrome and risk of atrial fibrillation within a year after the examination with the help of pharmacological antiarrhythmic therapy of atrial ectopia and modulated kinesotherapy as primary prevention in comparison with therapy aimed at correcting blood pressure, glucose and blood lipids.Aim. To assess the possibility of using antiarrhythmic drug therapy (DT) and modulated kinesitherapy (MK) in patients with metabolic syndrome (MS) and premature atrial complexes (PAC) as the primary prevention of atrial fibrillation (AF).Methods. 426 MS patients with PAC aged from 58 to 72 years (mean 66.4±0.7 years) were included in the study. All patients had a high probability of developing primary AF within 1 year after the enrollment. Antiarrhythmic DT with class I–III drugs was used as the primary prophylaxis of AF in 149 (34.97%) patients, MK – in 121 (28.40%), the correction of blood pressure, glucose and blood lipids – in 156 (36.63%). All patients were followed up for one year and the end point of observation was the maintenance of sinus rhythm or AF registration.Results. Various clinical forms of AF were recorded in 26.45, 31.54% and 95.51% of patients with MS during primary prevention with the help of pharmacological AAT, UA and correction of its potentially modifiable components (arterial pressure, glucose and blood lipids), respectively, during the year after the examination.Conclusion. The use of both antiarrhythmic DT of I–III classes, and MК as a primary prophylaxis of AF in patients with MS with PAC and the risk of AF development within one year after the first examination made it possible to reduce the frequency of the arrhythmia by the correction of blood pressure, glucose and blood lipids.

Risks and Benefits of Oral Anticoagulants for Stroke Prophylaxis in Atrial Fibrillation According to Body Mass Index: Nationwide Cohort Study of Primary Care Records in England

Risks and Benefits of Oral Anticoagulants for Stroke Prophylaxis in Atrial Fibrillation According to Body Mass Index: Nationwide Cohort Study of Primary Care Records in England

Direct oral anticoagulant: Review article.

Venous thromboembolism (VTE) and atrial fibrillation (AF) is a major burden on the health care system. The average occurrence of venous thromboembolism annually is around 108 per 100,000 person-year. DOACs have transformed treatment of coagulation disorder, and now, it is the leading treatment for stroke prevention in AF and VTE prophylaxis and treatment. For more many years, oral vitamin K antagonists (VKAs) were the drug of choice in managing VTE. VKAs treatment is safe and effective if therapeutic international normalized ratio (INR) maintained on the target. However, achieving a stable, therapeutic international normalized ratio (INR) can be difficult and challenging in the context of drug and food interactions and liver disorder, resulting in undertreatment which increases the risk of thromboembolism or overtreatment which might cause bleeding. Herein, we provide an overview of DOACs indications, use in specific comorbidities, monitoring parameters, perioperative management, and reversal agents.

Patient perception and treatment convenience of dabigatran versus vitamin K antagonist when used for stroke prophylaxis in atrial fibrillation: Real-world Evaluation of Long-term Anticoagulant Treatment Experience (RE-LATE) study

PurposeDabigatran is a direct thrombin inhibitor approved for stroke prophylaxis in patients with non-valvular atrial fibrillation (NVAF). Real-world data about patient preference, satisfaction and convenience in patients in Asia are...

M11. Magnesium Sulfate as Atrial Fibrillation Prophylaxis post Coronary Artery Bypass Graft Surgery: A Meta-analysis

Abstract Background and Aims Arrhythmia, especially atrial fibrillation (AF), is a common complication post coronary artery bypass graft (CABG) surgery and a major source of morbidity and mortality. This meta-analysis aims to evaluate the use of magnesium sulfate (MgSO4) as AF prophylaxis post CABG surgery. Method and Results A total of 10 studies enrolled 1,371 patients (1,114 males and 257 females) were retrieved from Pubmed, Cochrane, and Medline until July 2021 to identify studies about the association between MgSO4 and AF occurrence post CABG surgery. All suitable full text must accomplish Jadad score ≥2 for assessing study quality. Data were analyzed using Review Manager 5.3. Mantel-Haenszel formula was used for dichotomous variables to calculate the odds ratio (OR). Our results showed MgSO4 group (n = 711) compared to the placebo group (n = 660) were at decreased odds of having AF post CABG surgery (OR 0.59; 95%CI 0.39 to 0.91; p = 0.03) with AF occurrence in 134 patients and 188 patients, respectively. Data were derived from the random-effects model due to the heterogenous result between studies (Tau2=0.22, Chi2=18.99, df = 9 [p = 0.03], I2 = 53%). Conclusion This meta-analysis showed that administration of MgSO4 decreased the occurrence of AF occurrence post CABG surgery. Further research is needed to determine the optimal MgSO4 dose and time of administration.

Abstract 11107: Comparison of Left Atrial Appendage Occlusion and Direct Oral Anticoagulants and Warfarin in Patients with Atrial Fibrillation in Russian Prospective Registry

Introduction: Left atrial appendage occlusion (LAAO) is non-inferior to warfarin and direct oral anticoagulants (DOAC) in thromboembolic prophylaxis in atrial fibrillation (AF). However, these antithrombotic strategies in patients with and without contraindications to anticoagulants were not assessed separately before. Hypothesis: LAAO is superior to oral anticoagulants (OAC) in net clinical benefit in patients without contraindications for its usage, and superior to no thromboembolic prophylaxis in patients with contraindications for OAC. Methods: A prospective registry included 379 patients with nonvalvular AF and high risk of thromboembolic events. Patients were assigned into cohorts with and without contraindications to continuous therapy with OAC. In the first cohort patients with LAA occlusion (n=45), on DOAC (n=99) and on warfarin (n=100) were compared. In the second cohort patients with LAAO (n=75) were compared with those who received no antithrombotic prophylaxis (n = 60). The primary composite endpoint was net clinical benefit (all-cause mortality, ischemic stroke/transient ischemic attack/systemic embolism and major bleeding) in 3 years. Results: Using log-rank analysis of Kaplan-Meier curves in the cohort of patients without contraindications to OAC LAAO was superior to warfarin, reaching statistical significance (p=0.048), with a trend towards superiority over DOAC (p=0.061) . In the cohort of patients with contraindications to continuous OAC use, LAAO, in terms of both overall efficacy and safety, was significantly superior to no prophylaxis of thromboembolic events (p=0.003). (Figure 1). Conclusions: LAA occlusion demonstrated superiority to warfarin and no prophylaxis of thromboembolic events in terms of net clinical benefit. There was a trend to superiority of LAAO over DOAC in patients with contraindications to OAC.

Late onset atrial fibrillation in patients undergoing surgical aortic valve replacement.

Aortic valve disease is a risk factor for atrial fibrillation (AF), and AF is associated with increased late mortality and morbidity after cardiac surgery. The evolution of alternative approaches to AF prophylaxis, including less invasive technologies and medical therapies, has altered the balance between risk and potential benefit for prophylactic intervention at the time of surgical aortic valve replacement (SAVR). Such interventions impose incremental risk, however, making an understanding of predictors of new onset AF that persists beyond the perioperative episode relevant. We conducted a retrospective single-institution cohort analysis of patients undergoing SAVR with no history of preoperative AF (n = 1014). These patients were cross-referenced against an institutional electrocardiogram (ECG) database to identify those with ECGs 3-12 months after surgery. Logistic regression was used to identify predictors of late AF. Among the 401 patients (40%), who had ECGs in our institution 3-12 months after surgery, 16 (4%) had late AF. Patients with late AF were older than patients without late AF (73 vs. 65, p = .025), and underwent procedures that were more urgent/emergent (38% vs. 15%, p = .015), with higher predicted risk of mortality (2.2% vs. 1.3%, p = .012). Predictors associated with the development of late AF were advanced age, higher preoperative creatinine level and urgent/emergent surgery. The incidence of late AF 3-12 months after SAVR, is low. Prophylactic AF interventions at the time of SAVR may not be warranted.

Value of Atrial Fibrillation Prophylaxis after Coronary Artery Bypass Graft Surgery

Background: Heart surgery patients who develop acute and new-onset AF (postoperative atrial fibrillation, POAF) are among the most common postoperative complications, affecting around 35 percent of those who undergo the procedure. Objective: To assess the effectiveness of amiodarone in prophylaxis of AF post coronary artery bypass surgery (CABG). Patients and Methods: Our work represents a randomized clinical trial, which was carried out at National Heart Institute and Zagazig University from the period of August 2020 to June 2021. 68 patients, admitted for CABG and had high risk score according to POAF score, were included in our study. Results: Regarding mean left ventricular ejection fraction (LVEF), in group I was 47.52±5.85 while in group II it was 49.85±6.25. There was a statistically non-significant difference between the groups with a P value of 0.414. Mean Intensive Care Unit (ICU) period was 4.42±1.35 in group I, and group II was 2.73±0.95. The difference between the groups was statistically significantly shorter among group II (prophylaxis group) (P <0.01). Regarding development of POAF, in group I, the incidence of POAF was 85.3% while in group II, it was 38.2%. Difference among the two studied groups was statistically significantly lower in the group II (prophylaxis group). Conclusion: A prophylactic amiodarone strategy dramatically decreased incidence of POAF risk. All previous estimations of POAF risk reduction using prophylactic amiodarone were found to be accurate. Amiodarone was more effective in preventing postoperative atrial fibrillation with no serious side effects and it decreased postoperative ICU stay.

Association of Sex With Stroke and Bleeding Risk of Apixaban and Rivaroxaban in Elderly Atrial Fibrillation Patients Using Propensity Score Weights

BackgroundEvidence from clinical trials suggests a differential effect of sex on the effectiveness and safety of direct oral anticoagulants (DOACs) for stroke prophylaxis in atrial fibrillation (AF). MethodsThis population-based cohort study examined the independent effect of sex on hemorrhage and ischemic stroke in 23,884 patients (55% females; age ≥ 66 years) with AF starting apixaban or rivaroxaban treatment in Ontario, Canada. Patients were followed for 90 days after their DOAC prescription. Using female sex as the exposure of interest, differences in baseline characteristics were balanced between sexes using inverse probability weights based on propensity scores. Applying weighted modified Poisson regression, risk ratios (RRs) were estimated for major hemorrhage, ischemic stroke/systemic embolism/transient ischemic attack (hereafter stroke), myocardial infarction, and all-cause mortality, with males as a reference. ResultsFemales were older, had higher predicted stroke risk (based on CHADS2 score), and had fewer comorbidities than did males. Males had a higher prevalence of coronary artery disease, diabetes, and cancer, and similar predicted bleeding risk (based on HAS-BLED score). After weighting, baseline characteristics were well balanced. The 90-day risks for hemorrhage (RR 0.96; 95% confidence interval [CI] 0.80-1.15; P = 0.69) and stroke (RR 1.01; 95% CI 0.86-1.19; P = 0.94) were similar between sexes, which remained true when assessing each DOAC separately by dosing regimen. Compared to males, females had a lower risk for myocardial infarction (RR 0.66; 95% CI 0.52-0.84; P = 0.0008), and for all-cause mortality (RR 0.76; 95% CI 0.67-0.87; P < 0.0001). ConclusionsOur findings do not suggest an association of sex with the 90-day risk of hemorrhage or ischemic stroke in older AF patients prescribed apixaban or rivaroxaban.

Direct Oral Anticoagulants for Myeloproliferative Neoplasms (MPN-DOACs): Results from an International Study on 442 Patients

Direct Oral Anticoagulants for Myeloproliferative Neoplasms (MPN-DOACs): Results from an International Study on 442 Patients

Prescription of oral anticoagulation for stroke prophylaxis in atrial fibrillation according to frailty status: a national study of 536,995 primary care records

Abstract Background At least 10 million people in Europe have a diagnosis of atrial fibrillation (AF). People with AF commonly have concomitant frailty, rendering them vulnerable to various adverse outcomes. Whilst appropriate prescription of oral anticoagulation (OAC) is associated with reduced risk of stroke and mortality, there are fears of iatrogenic harm in older people with frailty. Purpose Previous studies give conflicting evidence of the association between frailty and OAC prescription and are based on small samples from select cohorts. Therefore, we provide data of the association between OAC prescription and frailty for a large representative cohort of patients with AF. Methods This cross-sectional study used EHR for 536,955 patients in England aged ≥65 years on 31/12/2015. Clinical Terms Version 3 (CTV-3) codes were used to identify AF and relevant past medical history (PMH, including: cancer, varices, intracranial or gastrointestinal haemorrhage). Frailty was determined according to the validated electronic frailty index (eFI, a cumulative deficit score of 36 possible deficits), and categorised into robust (0–0.12), mild (&amp;gt;0.12–0.24), moderate (&amp;gt;0.24–0.36) or severe (&amp;gt;0.36) frailty. Patients with a CHA2DS2-VASc score of ≥2 were considered eligible for OAC prescription. Prescription of OAC among those eligible (warfarin or direct oral anticoagulant [DOAC]) or not was established using prescribing data within the EHR. Poisson regression modelling was used to determine the odds of OAC prescription for each frailty category compared with non-frail (robust) individuals. Odds ratios (ORs) and 95% confidence intervals (CIs) were reported with and without adjustment for sex, deprivation, PMH, concomitant prescription of medications that increase bleeding risk (including antiplatelets, steroids, non-steroidal anti-inflammatories). Results Of the cohort, 61,177 (11.4%) had AF. Of these, 58,204 (95.1%) were eligible for OAC, which was prescribed in 30,916 (53.1%) people. Individuals prescribed OAC were on average 5 months younger than those not prescribed OAC (80.1 vs 80.5 years, p&amp;lt;0.001), and had a slightly higher CHA2DS2-VASc score (4.0 vs 3.8, p&amp;lt;0.001). Frailty was identified in 54,734 (89.5%) patients with AF. OAC was prescribed in 2,028 of 4,863 (41.7%) patients in the robust category; 10,221 of 19,198 (53.2%) with mild; 11,167 of 20,099 (55.6%) with moderate; and 7,500 of 14,044 (53.4%) with severe frailty. In comparison to the robust category, frailty was associated with higher odds of OAC prescription: mild frailty OR 1.6 (95% CI 1.5 to 1.7); moderate 1.7 (1.6 to 1.9); severe 1.6 (1.5 to 1.7). Adjustment for confounding variables increased the magnitude of the association (Figure 1). Conclusion People with AF and advancing frailty were more likely to be prescribed an anticoagulant than those with AF who are robust. Specific safety and efficacy data for OAC are needed in people with AF and frailty to better inform clinical decision-making. Figure 1 Funding Acknowledgement Type of funding source: Public hospital(s). Main funding source(s): CW was funded by the Hull-York Medical School. He is now an NIHR clinical lecturer.

Development and Validation of A Simple Clinical Risk Prediction Model for New-Onset Postoperative Atrial Fibrillation After Cardiac Surgery: Nopaf Score.

Postoperative atrial fibrillation (POAFib) occurs in 20 to 40% of patients following cardiac surgery, and is associated with an increased perioperative morbidity and mortality. We aimed to develop and validate a simple clinical risk model for the prediction of POAFib after cardiac surgery. An analytical single center retrospective cohort study was conducted, including consecutive patients undergoing cardiac surgery between 2004 and 2017 with POAFib. To create the predictive risk score, a logistic regression model was performed using a random sample of 75% of the population. Coefficients of the model were then converted to a numerical risk score, and three groups were defined: low risk (≤1 point), intermediate risk (2-5 points) and high risk (≥6 points). The score was validated using the remaining 25% of the patients. Discrimination was evaluated through the area under the curve (AUC) ROC, and calibration using the Hosmer-Lemeshow (HL) test, calibration plots, and ratio of expected and observed events (E/O). Six thousand five hundred nine patients underwent cardiac surgery: 52% coronary artery bypass grafting (CABG), 20% valve surgery, 14% combined (CABG and valve surgery) and 12% other. New-onset AF occurred in 1222 patients (18.77%). In the multivariate analysis, age, use of cardiopulmonary bypass pump, severe reduction in left ventricular ejection fraction (LVEF), chronic renal disease and heart failure were independent risk factors for POAFib, while the use of statins was a protective factor. The NOPAF score was calculated by adding points for each independent risk predictor. In the derivation cohort, the AUC was 0.71 (CI95% 0.69-0.72), and in the validation cohort the model also showed good discrimination (AUC 0.67 IC 0.64-0.70) and excellent calibration (HL P = 0.24). The E/O ratio was 1 (CI 95%: 0.89-1.12). According to the risk category, POAFib occurred in 5% of low; 11% of intermediate and 27.7% of high risk patients in the derivation cohort (P <0.001), and 5.7%; 12.6%; and 23.6% in the validation cohort respectively (P <0.001). From a large hospitalized population, we developed and validated a simple risk score named NOPAF, based on clinical variables that accurately stratifies the risk of POAFib. This score may help to identify high-risk patients prior to cardiac surgery, in order to strengthen postoperative atrial fibrillation prophylaxis.