This study examined the risks of ischemic stroke and bleeding in 2,304 patients over 65 years old who were hospitalized with secondary atrial fibrillation (AF) associated with acute coronary syndrome (ACS), acute pulmonary disease, or sepsis. The patients had high risk scores for stroke and bleeding. While most patients received anticoagulants, the study found anticoagulant use did not lower ischemic stroke risk overall and increased bleeding risk in those with pulmonary disease. Thus, the benefits of anticoagulation for secondary AF linked to ACS, pulmonary disease, or sepsis remain unclear.

2. Introduction
Secondary AF Defined as , arrhythmia that is self-limited and
caused by a reversible etiology.
Secondary AF has been observed in multiple clinical conditions
Acute myocardial infarction
Myocarditis
Pericarditis
Acute pulmonary disease
Post-operative states
Thyrotoxicosis
Acute alcohol consumption
Sepsis

3. Methods
a retrospective cohort study of patients with secondary
AF associated with ACS , acute pulmonary disease, or sepsis.
2,304 patients , 65 years or older, Participants in the a
retrospective cohort study , discharged alive from the hospital
with a primary diagnosis of a known reversible cause of AF .
The information was gathered between 1999 and 2015.
The primary outcomes were ischemic stroke and bleeding,
documented at first hospital admission or emergency department
visit following discharge.

5. Results
2,304 patients grouped into 3 groups , ACS (n=827) , acute
pulmonary diseases (n=1375)
(COPD,influenza,pneumonia,PE,pleural effusion) , sepsis (n=102).
Patients were elderly (mean age: 77.1 to 79.3 years) and frequently
had co-morbid illness including coronary artery disease, CHF, CKD,
hyperlipidemia, and diabetes.
Most patients had high CHADS2 scores≥2 (66.5% ACS , 60.9% acute
pulmonary disease , 65.95 sepsis) , and high HASBLED scores≥3
(59.3% ACS,47.4% acute pulmonary disease , 55.9% sepsis).
Mean follow up was – 3.6 years for ACS , 3.1 years for acute
pulmonary disease , 3.1 years for Sepsis.

6. Incidence of Stroke

7. Incidence of bleeding

8. Discussion And Conclusion
Follow-up of 3 years, our study found that anticoagulant use was
not associated with a lower risk of ischemic stroke in patients with
new-onset AF associated with ACS, acute pulmonary disease, and
sepsis.
Meanwhile, anticoagulant use was associated with a higher risk of
bleeding in patients with acute pulmonary disease.
Study included patients who were all older adults (age >65 years),
who also had frequent comorbidities.
Thus 45% to 60% of patients had high HASBLED scores (≥3) and
60% to 65% of patients had high CHADS score (≥2) , despite our
high-risk patient populations, we did not observe this benefit to
anticoagulation.
The benefits of anticoagulation in patients who develop secondary
AF associated with ACS, acute pulmonary disease, or sepsis
remains unclear.