Incidence of atrial fibrillation/flutter, one-year re-admission rates, and practice patterns among patients <65 years of age: a Danish nationwide study

Background/Introduction

The general atrial fibrillation/flutter (AF) population is well explored and described, but there is sparse data on temporal changes in the incidence, AF-readmission rates, and practice patterns in patients with AF under 65 years of age from unselected cohorts.

Purpose

To investigate temporal changes, AF readmission rates, and practice patterns in patients under 65 years of age with first-time AF diagnosed between 2000–2018.

Methods

Using Danish nationwide registries, we identified patients >18 years and <65 years with a first-time AF-diagnosis from 2000–2018. The cohort was categorized according to calendar periods; 2000–2002, 2003–2006, 2007–2010, 2011–2014 and 2015–2018. Incidence rate (IR) of AF per 100,000 person years (PY), AF-readmission, and practice patterns of medical treatment, electrical cardioversion, and catheter ablation was investigated in the first year following AF-diagnosis.

Results

In this study 60,917 patients were included; 8,150 patients (13.4%) in 2000–2002, 11,898 (19.5%) in 2003–2006, 13,560 (22.3%) in 2007–2010, 14,167 (23.3%) in 2011–2014 and 13,142 (21.6%) in 2015–2018. No major differences were seen in patient characteristics according to calendar period. A stepwise increase, as seen in the Table, in the crude IR of AF per 100,000 PY was observed across calendar periods, except for 2015–2018 (Crude IR [95% CI]: 2000–2002: 78.7 [77.0; 80.4], 2003–2006: 86.3 [84.7; 87.8], 2007–2010: 97.9 [96.3; 99.6], 2011–2014: 102.3 [100.7; 104.0], 2015–2018: 93.6 [92.0; 95.2], while no difference in AF readmission was identified (AF-readmissions: 2000–2002: 32.7%, 2003–2006: 31.1%, 2007–2010: 32.2%, 2011–2014: 32.1% and 2015–2018: 31.7%), as seen in the Figure, right panel. In the first year following AF-diagnosis, the cumulative incidence of catheter ablation increased stepwise from 1.2% in 2000–2002 to 7.6% in 2015–2018 and electrical cardioversion from 2.0% in 2000–2002 to 8.7% in 2015–2018 (Figure, left panel). Treatment with oral anticoagulant therapy (OAC) increased from 28.5% in 2000–2002 to 47.8% in 2015–2018, while there was no change in treatment with rhythm or rate medication therapy.

Conclusion

From 2000–2018, we found an increase in the incidence of atrial fibrillation/flutter (AF) in patients <65 years from 78.7/100,000 person years (PY) to 93.6/100,000 PY and an increase in the use of catheter ablation, electrical cardioversion and OAC in the first year following first-time AF-diagnosis. AF readmission rates were stable over calendar periods.

Funding Acknowledgement

Type of funding sources: None.

Prognosis and antithrombotic practice patterns in recurrent and transient atrial fibrillation following acute coronary syndrome: a nationwide study

Background

First-time detected atrial fibrillation (AF) during acute coronary syndrome (ACS) aggravates the prognosis and increases the risk of ischemic stroke. In this setting, AF may present as brief and transient or with recurrent episodes after discharge. However, data on the association between transient or recurrent AF and ischemic stroke in patients with ACS are sparse. Further, despite being associated with ischemic stroke, first-time detected AF patients have been reported with low oral anticoagulation (OAC) rates.

Purpose

To examine the associated rate of ischemic stroke and mortality in ACS survivors with transient or recurrent AF and to assess the antithrombotic practice patterns one year after ACS.

Methods

Using data from Danish nationwide registries, we identified all patients with first-time ACS, without known AF prior to ACS, from 2000–2017 who were alive one year after ACS discharge (index date). According to a grace period between ACS discharge and one year after ACS discharge, patients were categorized into: i) no AF; ii) first-time detected AF during ACS admission without AF recurrence (transient AF); and iii) first-time detected AF during ACS admission with a subsequent recurrent AF episode (recurrent AF). Patients who developed AF during the grace period were excluded. Patients were followed from one year post ACS discharge, and two-year rates of ischemic stroke and mortality were compared using multivariable adjusted Cox proportional hazards analysis. Further, we assessed the prescribed OAC rates in a three-month period following the index date.

Results

We included 116,793 patients surviving one year post ACS discharge: 111,708 (95.6%) without AF (64.9% male, median age 64 years), 2,671 (2.3%) with transient AF (58.0% male, median age 74 years), and 2,414 (2.1%) with recurrent AF (55.2% male, median age 76 years). The cumulative two-year incidence of ischemic stroke was 0.9%, 1.5%, and 2.3% for patients without AF, transient AF, and recurrent AF, respectively (Figure 1). The cumulative two-year incidence of mortality was 7.4%, 12.1%, and 20.3% for patients without AF, transient AF, and recurrent AF, respectively (Figure 1). Compared to those without AF, the adjusted two-year rates of outcomes were as follows: ischemic stroke: HR 1.15 (95% CI: 0.81–1.61) for patients with transient AF and HR 1.50 (95% CI: 1.14–1.98) for patients with recurrent AF; mortality: HR 0.98 (95% CI: 0.87–1.10) for patients with transient AF and HR 1.35 (95% CI: 1.23–1.49) for patients with recurrent AF (Figure). We identified that 20.9% for transient AF and 42.2% for recurrent AF were prescribed OAC therapy in the three-month period after one year.

Conclusion

In patients surviving one year after ACS with first-time detected AF, a recurrent AF episode was associated with an increased long-term rate of ischemic stroke and mortality, while transient AF yielded no statistically difference as compared with patients without AF.

Funding Acknowledgement

Type of funding sources: None.

Rehospitalizations, repeated aortic surgery, and death in initial survivors of surgery for Stanford type A aortic dissection and the significance of age – a nationwide registry-based cohort study

Background

All patients with type A aortic dissections, regardless of age, are recommended urgent aortic surgery. However, studies exploring long term outcomes in survivors are sparse, and especially, the significance of age on long-term outcomes remain unclear.

Purpose

We described and compared incidences across age groups of post-discharge readmission, repeated aortic surgery, and death in patients who survived surgery and hospitalization for type A aortic dissection.

Methods

Using data from Danish nationwide registries, we identified patients hospitalized with Stanford type A aortic dissections from 2006–2018. Survivors of hospitalization and surgery on the ascending aorta and/or aortic arch comprised the study population (Figure 1). Using cumulative incidence plots taking death into account as a competing risk and Cox regression analysis, we described long-term outcomes (rehospitalizations, repeated aortic surgery, and death) and compared different age groups. The diagnosis of type A aortic dissection in the registries used, was validated from 191 clinical records to have a positive predictive value of 94.8%.

Results

Of 606 initial survivors of surgery and hospitalization with type A aortic dissection, 236 (38.9%) were <60 years old (group I), 194 (32.0%) were 60–69 years old (group II), and 176 (29.1%) were >69 years old (group III). Figure 2 shows cumulative incidences of outcomes according to age. During the first year, 62.5% were re-hospitalized (median number of days hospitalized was 2 days (IQR 1–8 days) and 1.4% underwent repeated aortic surgery with no significant differences across age groups (P=0.68 and P=0.39, respectively). Further, 5.9% died (group I: 3.0%, group II: 8.3%, group III: 7.4%, P=0.04). After 10 years of follow up, 8.0% had undergone repeated aortic surgery (group I: 11.5%, group II: 8.5%, group III: 1.6%, P=0.04) and 10.2% (group I), 17.0% (group II), and 22.2% (group III) had died (P=0.01). In adjusted analyses, no age differences were found in one-year outcomes, while age >69 years (group III) compared with age <60 years (group I) was associated with a lower rate of repeated aortic surgery (hazard ratio 0.17, 95% confidence interval 0.04–0.78) and a higher rate of all-cause mortality (hazard ratio 2.44, 95% confidence interval 1.37–4.34) in the 10-years analysis.

Conclusion

Among survivors of type A aortic dissections, rehospitalizations the first year after discharge were common among all age groups, but survival was high. Repeated aortic surgery was rare, and significantly more common among younger than older patients. Evaluations of quality of life in survivors of type A aortic dissections are needed.

Funding Acknowledgement

Type of funding sources: None.

Perioperative atrial fibrillation in major emergency abdominal surgery: does it affect postoperative outcome?

Background

Atrial fibrillation (AF) in relation to surgery remains a clinical challenge. Major emergency abdominal surgery (e.g. ileus, perforation) is associated with postoperative complications and mortality. However, the prevalence and impact of perioperative AF in this setting is not well examined.

Purpose

We compared 30-days and 1-year outcomes (i.e. hospitalization of any causes, AF-related hospitalization, thromboembolic events and all-cause mortality) in patients who did and did not develop perioperative AF (POAF) in relation to their major emergency abdominal surgery.

Methods

We crosslinked data from Danish nationwide registries and identified all patients who underwent major emergency abdominal surgery (2000–2018) and discharged alive. Patients who developed POAF during hospitalization were matched in a 1:3 ratio on age, sex, year of surgery and category of surgery with those without POAF. Starting follow up at discharge, we examined the rates of outcomes at 30-days and 1-year post-discharge. The cumulative incidences and ratios of outcomes were assessed with the Aalen Johanson estimator together with Kaplan-Meier estimator and multivariable Cox regression analysis, respectively.

Results

We identified 891 patients with POAF and 64,914 patients without POAF. The matched cohort were composed of 889 patients with POAF and 2667 patients without POAF with a median age of 79 years [25th-75th percentile; 72–84 years] and 45.2% males. In general, patients with POAF had higher comorbid burden compared with patients without POAF. The cumulative incidences of a hospitalization of any cause after 30-days post-discharge were 31.2% and 22.3% in patients with and without POAF, respectively. The corresponding numbers for AF-related hospitalization were 20.8% and 1.2%, respectively. In adjusted analyses, POAF was associated with a significantly higher risk of hospitalization of any causes together with AF-related hospitalization (Figure 1 and 2).

The cumulative incidences of a thromboembolic event after 30-days post-discharge were 2.2% and 0.9% in patients with and without POAF, respectively. The corresponding numbers for all-cause mortality were 9.7% and 3.2%, respectively. In adjusted analyses, POAF was associated with a significantly higher risk of a thromboembolic event together with all-cause mortality within 30-days of follow up as well as 1-year of follow up. However, the results regarding thromboembolic events did not reach statistical significance after 1-year of follow up (Figure 1 and 2).

Conclusions

Perioperative atrial fibrillation in relation to major emergency abdominal surgery was associated with higher 30-days and 1-year rates of hospitalizations of any causes, atrial fibrillation related hospitalization, a thromboembolic event and all-cause mortality. These findings suggest that perioperative atrial fibrillation is a strong prognostic marker of increased morbidity following major emergency abdominal surgery.

Funding Acknowledgement

Type of funding sources: None.

Time trends and patient selection in the use of continuous electrocardiography for detecting atrial fibrillation after stroke: a nationwide cohort study

BACKGROUND AND PURPOSE

Clinical use of continuous electrocardiography (cECG) for detecting atrial fibrillation (AF) after stroke is unclear. In a Danish nationwide cohort, we described post-stroke time trends in outpatient cECG usage and AF incidence and characterized factors associated with cECG use.

METHODS

Patients without AF discharged after their first ischaemic stroke between 2010 and 2016 were identified from Danish nationwide registries. cECG included Holter or event recording within 120 days from discharge. Cumulative incidence analysis and multivariable adjusted logistic regression were used to assess time trends and factors associated with cECG usage and AF.

RESULTS

The study population comprised 39 641 patients. Cumulative use of cECG increased threefold from 3.3% [95% confidence intervals (CI), 2.8-3.8] in 2010 to 10.5% (95% CI, 9.7-11.3) in 2016. Correspondingly, cumulative incidence of post-stroke AF increased from 1.9% (95% CI, 1.5-2.3) to 2.8% (95% CI, 2.4-3.2). Of all cECG-evaluated patients, 6.3% received an AF diagnosis versus 2.2% of the unevaluated. Receiving cECG was associated with increased odds of AF (odds ratio, 3.4; 95% CI, 2.8-4.0). Lower age, milder strokes and less comorbidity were associated with increased odds of receiving cECG. In contrast, risk factors for AF were increasing age and more comorbidity.

CONCLUSIONS

Post-stroke outpatient cECG use and AF incidence have increased over time, but screening rates were low. cECG use was associated with tripled odds of detecting AF. There was a disparity between factors associated with cECG use and risk factors of AF. This raise questions as to the appropriateness of the current clinical approach to post-stoke AF detection.

P4799Long-term thromboembolic risk in patients with postoperative atrial fibrillation after left-sided heart valve surgery

Background

New-onset postoperative atrial fibrillation (POAF) is a common complication of cardiac surgery. However, data on the long-term risk of thromboembolism in patients who develop POAF after heart valve surgery are sparse. In addition, data on stroke prophylaxis in this setting are lacking.

Objective

To assess the long-term risk of thromboembolism in patients developing new-onset POAF following isolated left-sided heart valve surgery relative to patients with nonsurgical, nonvalvular atrial fibrillation (NVAF).

Methods

Using data from the Eastern Danish Heart Surgery Database and Danish nationwide registries, we identified patients who developed POAF following isolated left-sided heart valve surgery (i.e. biologic aortic/mitral valve replacement or aortic/mitral valve repair) from 2000 through 2015. These patients were matched with patients with nonsurgical NVAF in a 1:4 ratio by age, sex, heart failure, hypertension, diabetes, a history of thromboembolism, ischemic heart disease, and year of diagnosis. Long-term risk of thromboembolism was examined by the Aalen-Johansen estimator and cause-specific Cox regression models adjusted for comorbidities, concomitant pharmacotherapy, and oral anticoagulation therapy as a time-dependent covariate.

Results

A total of 1,539 patients undergoing isolated left-sided heart valve surgery were identified. Of these, 716 (46.5%) patients developed POAF after surgery. A total of 630 patients with POAF were matched with 2,520 patients with NVAF. In the matched study population, the median age was 71 years (25th-75th percentile 66–77 years) and 59.5% were men. Oral anticoagulation therapy was initiated within 30 days post-discharge in 62.7% and 51.4% of these patients, respectively. Compared with NVAF, POAF was not associated with a significantly different 5-year absolute risk of thromboembolism (10.7% [95% confidence interval [CI], 8.0%-13.9%] versus 8.9% [95% CI, 7.6%-10.2%] in the POAF and NVAF group, respectively) (Figure). In the adjusted analysis, the long-term risk of thromboembolism was similar in patients with POAF and NVAF (hazard ratio [HR] 1.01 [95% CI, 0.71–1.44]). Anticoagulation therapy during follow-up was associated with a lower risk of thromboembolic events in patients with POAF (HR 0.45 [95% CI, 0.18–0.99]) as well as NVAF (HR 0.58 [95% CI, 0.42–0.80]) compared with no anticoagulation therapy.

Conclusions

New-onset POAF following isolated left-sided heart valve surgery was associated with a similar long-term risk of thromboembolism compared with NVAF. Future studies addressing the role of oral anticoagulation therapy in POAF after heart valve surgery are warranted to examine the efficacy and safety as well as the timing and duration of anticoagulation therapy.

Comparative thromboembolic risk in atrial fibrillation with and without a secondary precipitant-Danish nationwide cohort study

OBJECTIVES

We compared long-term outcomes in patients with atrial fibrillation (AF) with and without a secondary precipitant.

DESIGN AND SETTING

Retrospective cohort study based on Danish nationwide registries.

PARTICIPANTS

Patients with AF with and without secondary precipitants (1996-2015) were matched 1:1 according to age, sex, calendar year, CHA₂DS₂-VASc score and oral anticoagulation therapy (OAC), resulting in a cohort of 39 723 patients with AF with a secondary precipitant and the same number of patients with AF without a secondary precipitant. Secondary precipitants included alcohol intoxication, thyrotoxicosis, myocardial infarction, surgery and infection in conjunction with AF.

PRIMARY AND SECONDARY OUTCOMES

The primary outcome in this study was thromboembolic events. Secondary outcomes included AF rehospitalisation and death. Long-term risks of outcomes were examined by multivariable Cox regression analysis.

RESULTS

The most common precipitants were infection (55.0%), surgery (13.2%) and myocardial infarction (12.0%). The 5-year absolute risk of thromboembolic events (taking death into account as a competing risk) in patients with AF grouped according to secondary precipitants were 8.3% (alcohol intoxication), 8.5% (thyrotoxicosis), 12.1% (myocardial infarction), 11.6% (surgery), 12.2% (infection), 10.1% (>1 precipitant) and 12.3% (no secondary precipitant). In the multivariable analyses, AF with a secondary precipitant was associated with the same or an even higher thromboembolic risk than AF without a secondary precipitant. One exception was patients with AF and thyrotoxicosis: those not initiated on OAC therapy carried a lower thromboembolic risk the first year of follow-up than matched patients with AF without a secondary precipitant and no OAC therapy.

CONCLUSIONS

In general, AF with a secondary precipitant was associated with the same thromboembolic risk as AF without a secondary precipitant. Consequently, this study highlights the need for more research regarding the long-term management of patients with AF associated with a secondary precipitant.

Initiation of anticoagulation in atrial fibrillation: which factors are associated with choice of anticoagulant?

BACKGROUND

The use of non-vitamin K antagonist oral anticoagulants (NOACs) for stroke prophylaxis in atrial fibrillation (AF) is increasing rapidly. We compared characteristics of AF patients initiated on NOACs versus vitamin K antagonists (VKAs).

METHODS

Using Danish nationwide registry data, we identified AF patients initiating either a VKA or a NOAC from 22 August 2011 until 30 September 2016. We compared patient characteristics including age, gender, comorbidities, concomitant pharmacotherapy and CHA₂ DS₂ -VASc and HAS-BLED scores in patients initiated on a VKA, dabigatran, rivaroxaban or apixaban. Differences were examined using multivariable logistic regression models.

RESULTS

The study population comprised 51 981 AF patients of whom 19 989 (38.5%) were initiated on a VKA, 13 242 (25.5%) on dabigatran, 8475 (16.3%) on rivaroxaban and 10 275 (19.8%) on apixaban. Those patients initiated on apixaban had higher mean ± SD CHA₂ DS₂ -VASc scores than those initiated on a VKA (3.1 ± 1.6 vs. 2.9 ± 1.6). Those initiated on dabigatran had lower mean CHA₂ DS₂ -VASc scores (2.7 ± 1.6) than all other groups. Patients with a history of a prior stroke were significantly more likely to be initiated on a NOAC compared with a VKA [odds ratio (OR) 1.35, 95% confidence interval (CI) 1.28-1.43]. By contrast, patients with a history of myocardial infarction were less likely to be initiated on a NOAC compared with a VKA (OR 0.72, 95% CI 0.67-0.77).

CONCLUSIONS

Atrial fibrillation patients who were initiated on apixaban had higher stroke risk scores than patients initiated on VKAs. Interestingly, opposite results were found for dabigatran.