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Anticoagulation and Antiplatelet Therapy for Atrial Fibrillation and Stable Coronary Disease: Meta-Analysis of Randomized Trials

Author/s: 
Sina Rashedi, Mohammad Keykhaei, Alyssa Sato, Philippe Gabriel Steg

Background: The optimal long-term antithrombotic strategy in patients with atrial fibrillation (AF) and stable coronary artery disease (CAD) remains uncertain. Individual randomized controlled trials (RCTs) had variations in their reported results and were not powered for effectiveness outcomes.

Objectives: This study aimed to pool the results of RCTs comparing the effectiveness and safety of oral anticoagulation (OAC) monotherapy vs OAC plus single antiplatelet therapy (SAPT) in patients with AF and stable CAD.

Methods: We systematically searched PubMed, Embase, and ClinicalTrials.gov until September 09, 2024. The primary effectiveness outcome was a composite of myocardial infarction, ischemic stroke, systemic embolism, or death. The primary safety outcome was major bleeding. We obtained unpublished results from principal investigators of the included RCTs, as needed, to calculate pooled HRs and 95% CIs and to perform prespecified subgroup analyses.

Results: Among 690 screened records, 4 RCTs with 4,092 randomized patients were included (2 using edoxaban, 1 using rivaroxaban, and 1 using any oral anticoagulant; mean age 73.9 years, 20.1% women). The median follow-up durations ranged from 12 to 30 months (overall estimated weighted mean follow-up of 21.9 months). There were no statistically significant differences between OAC monotherapy vs OAC plus SAPT in the primary effectiveness outcome (7.3% vs 8.2%; HR: 0.90; 95% CI: 0.72-1.12), myocardial infarction (1.0% vs 0.7%; HR: 1.51; 95% CI: 0.75-3.04), ischemic stroke (1.9% vs 2.1%; HR: 0.89; 95% CI: 0.57-1.37), all-cause death (4.2% vs 5.3%; HR: 0.94; 95% CI: 0.49-1.80), or cardiovascular death (2.4% vs 3.0%; HR: 0.79; 95% CI: 0.54-1.15). OAC monotherapy was associated with a lower risk of major bleeding than OAC plus SAPT (3.3% vs 5.7%; HR: 0.59; 95% CI: 0.44-0.79). Subgroup analyses did not show significant interactions for effectiveness but suggested that the magnitude of bleeding reduction may be greater among men (Pinteraction = 0.03) and among patients with diabetes mellitus (Pinteraction = 0.04).

Conclusions: In patients with AF and stable CAD, OAC monotherapy, compared with OAC plus SAPT, was not associated with a statistically significant increased risk of ischemic events but resulted in a significantly reduced risk of bleeding.

Keywords 
anticoagulants atrial fibrillation coronary artery disease ischemia platelet aggregation inhibitors

Management of Atrial Fibrillation

Author/s: 
Francis J Alenghat, Jason T Alexander, Gaurav A Upadhyay

Atrial fibrillation has a lifetime prevalence of 15% to 40% and predisposes patients to stroke and cardiac dysfunction. This JAMA Clinical Guidelines Synopsis focuses on recommendations for long-term management of AF, including new paradigms for rhythm control and stroke risk reduction.

Keywords 
atrial fibrillation coronary artery disease heart disease Cardiology Rhythm Disorders heart failure

Perioperative Management of Anticoagulant and Antiplatelet Therapy

The management of patients who are receiving an anticoagulant or antiplatelet drug and require surgery or an invasive procedure is a common clinical problem encountered by a broad spectrum of health care professionals. This review provides an evidence-based but practical approach to common clinical scenarios involving patients who require an elective surgery/procedure and are receiving either a vitamin K antagonist, a direct oral anticoagulant, or single or dual antiplatelet therapy. This review also addresses the role of perioperative heparin bridging and the management of patients who are receiving an anticoagulant drug and need urgent surgery.

Keywords 
anticoagulants antiplatelet surgery heparin

Transient ischemic attack and minor stroke: diagnosis, risk stratification and management

Author/s: 
Perry, J. J., Yadav, K., Syed, S., Shamy, M.

Patients with suspected cerebral ischemia should be urgently assessed to distinguish between transient ischemic attack (TIA), minor stroke or mimics such as migraine, seizure, vertigo or syncope.

The Canadian TIA Score can be used to determine risk for early subsequent stroke in patients with a suspected TIA or minor stroke.

All patients with TIA or minor stroke should undergo urgent electrocardiography and computed tomography of the head.

Clinicians should order early vascular imaging for patients at moderate or high risk of subsequent stroke; urgent revascularization should be considered if there is more than 50% arterial stenosis congruent with symptom presentation.

Clinicians should prescribe dual antiplatelet drugs for high-risk patients, single antiplatelet agents for low-risk patients or direct oral anticoagulants for patients with atrial fibrillation.

All patients with TIA or minor stroke should be counselled about modifiable lifestyle factors (including smoking cessation), be treated with statins and take steps toward optimizing blood pressure, including treatment with antihypertensive drugs, if necessary.

Keywords 
atrial fibrillation Brain Ischemia Cerebral Infarction Migraine Disorders electrocardiography

Hematuria as a Marker of Occult Urinary Tract Cancer: Advice for High-Value Care From the American College of Physicians

Author/s: 
Nielsen, Matthew, Qaseem, Amir, High Value Care Task Force of the American College of Physicians

Background: The presence of blood in the urine, or hematuria, is a common finding in clinical practice and can sometimes be a sign of occult cancer. This article describes the clinical epidemiology of hematuria and the current state of practice and science in this context and provides suggestions for clinicians evaluating patients with hematuria.

Methods: A narrative review of available clinical guidelines and other relevant studies on the evaluation of hematuria was conducted, with particular emphasis on considerations for urologic referral.

High-value care advice 1: Clinicians should include gross hematuria in their routine review of systems and specifically ask all patients with microscopic hematuria about any history of gross hematuria.

High-value care advice 2: Clinicians should not use screening urinalysis for cancer detection in asymptomatic adults.

High-value care advice 3: Clinicians should confirm heme-positive results of dipstick testing with microscopic urinalysis that demonstrates 3 or more erythrocytes per high-powered field before initiating further evaluation in all asymptomatic adults.

High-value care advice 4: Clinicians should refer for further urologic evaluation in all adults with gross hematuria, even if self-limited.

High-value care advice 5: Clinicians should consider urology referral for cystoscopy and imaging in adults with microscopically confirmed hematuria in the absence of some demonstrable benign cause.

High-value care advice 6: Clinicians should pursue evaluation of hematuria even if the patient is receiving antiplatelet or anticoagulant therapy.

High-value care advice 7: Clinicians should not obtain urinary cytology or other urine-based molecular markers for bladder cancer detection in the initial evaluation of hematuria.

Diagnosis and Management of Transient Ischemic Attack and Acute Ischemic Stroke: A Review

Author/s: 
Mendelson, Scott J., Prabhakaran, Shyam

Importance: Stroke is the fifth leading cause of death and a leading cause of disability in the United States, affecting nearly 800 000 individuals annually.

Observations: Sudden neurologic dysfunction caused by focal brain ischemia with imaging evidence of acute infarction defines acute ischemic stroke (AIS), while an ischemic episode with neurologic deficits but without acute infarction defines transient ischemic attack (TIA). An estimated 7.5% to 17.4% of patients with TIA will have a stroke in the next 3 months. Patients presenting with nondisabling AIS or high-risk TIA (defined as a score ≥4 on the age, blood pressure, clinical symptoms, duration, diabetes [ABCD2] instrument; range, 0-7 [7 indicating worst stroke risk]), who do not have severe carotid stenosis or atrial fibrillation, should receive dual antiplatelet therapy with aspirin and clopidigrel within 24 hours of presentation. Subsequently, combined aspirin and clopidigrel for 3 weeks followed by single antiplatelet therapy reduces stroke risk from 7.8% to 5.2% (hazard ratio, 0.66 [95% CI, 0.56-0.77]). Patients with symptomatic carotid stenosis should receive carotid revascularization and single antiplatelet therapy, and those with atrial fibrillation should receive anticoagulation. In patients presenting with AIS and disabling deficits interfering with activities of daily living, intravenous alteplase improves the likelihood of minimal or no disability by 39% with intravenous recombinant tissue plasminogen activator (IV rtPA) vs 26% with placebo (odds ratio [OR], 1.6 [95% CI, 1.1-2.6]) when administered within 3 hours of presentation and by 35.3% with IV rtPA vs 30.1% with placebo (OR, 1.3 [95% CI, 1.1-1.5]) when administered within 3 to 4.5 hours of presentation. Patients with disabling AIS due to anterior circulation large-vessel occlusions are more likely to be functionally independent when treated with mechanical thrombectomy within 6 hours of presentation vs medical therapy alone (46.0% vs 26.5%; OR, 2.49 [95% CI, 1.76-3.53]) or when treated within 6 to 24 hours after symptom onset if they have a large ratio of ischemic to infarcted tissue on brain magnetic resonance diffusion or computed tomography perfusion imaging (modified Rankin Scale score 0-2: 53% vs 18%; OR, 4.92 [95% CI, 2.87-8.44]).

Conclusions and relevance: Dual antiplatelet therapy initiated within 24 hours of symptom onset and continued for 3 weeks reduces stroke risk in select patients with high-risk TIA and minor stroke. For select patients with disabling AIS, thrombolysis within 4.5 hours and mechanical thrombectomy within 24 hours after symptom onset improves functional outcomes.

Keywords 
blood pressure stroke transient ischemic attack Acute Ischemic Stroke

Outcomes Associated With Oral Anticoagulants Plus Antiplatelets in Patients With Newly Diagnosed Atrial Fibrillation

Author/s: 
Fox, KAA, Velentgas, P, Camm, AJ, Bassand, JP, Fitzmaurice, DA, Gersh, BJ, Goldhaber, SZ, Goto, S, Haas, S, Misselwitz, F, Pieper, KS, Turpie, AGG, Verhegut, FWA, Dabrowski, E, Luo, K, Gibbs, L, Kakkar, AK, GARFIELD-AF Investigators

IMPORTANCE:

Patients with nonvalvular atrial fibrillation at risk of stroke should receive oral anticoagulants (OAC). However, approximately 1 in 8 patients in the Global Anticoagulant Registry in the Field (GARFIELD-AF) registry are treated with antiplatelet (AP) drugs in addition to OAC, with or without documented vascular disease or other indications for AP therapy.

OBJECTIVE:

To investigate baseline characteristics and outcomes of patients who were prescribed OAC plus AP therapy vs OAC alone.

DESIGN, SETTING, AND PARTICIPANTS:

Prospective cohort study of the GARFIELD-AF registry, an international, multicenter, observational study of adults aged 18 years and older with recently diagnosed nonvalvular atrial fibrillation and at least 1 risk factor for stroke enrolled between March 2010 and August 2016. Data were extracted for analysis in October 2017 and analyzed from April 2018 to June 2019.

EXPOSURE:

Participants received either OAC plus AP or OAC alone.

MAIN OUTCOMES AND MEASURES:

Clinical outcomes were measured over 3 and 12 months. Outcomes were adjusted for 40 covariates, including baseline conditions and medications.

RESULTS:

A total of 24 436 patients (13 438 [55.0%] male; median [interquartile range] age, 71 [64-78] years) were analyzed. Among eligible patients, those receiving OAC plus AP therapy had a greater prevalence of cardiovascular indications for AP, including acute coronary syndromes (22.0% vs 4.3%), coronary artery disease (39.1% vs 9.8%), and carotid occlusive disease (4.8% vs 2.0%). Over 1 year, patients treated with OAC plus AP had significantly higher incidence rates of stroke (adjusted hazard ratio [aHR], 1.49; 95% CI, 1.01-2.20) and any bleeding event (aHR, 1.41; 95% CI, 1.17-1.70) than those treated with OAC alone. These patients did not show evidence of reduced all-cause mortality (aHR, 1.22; 95% CI, 0.98-1.51). Risk of acute coronary syndrome was not reduced in patients taking OAC plus AP compared with OAC alone (aHR, 1.16; 95% CI, 0.70-1.94). Patients treated with OAC plus AP also had higher rates of all clinical outcomes than those treated with OAC alone over the short term (3 months).

CONCLUSIONS AND RELEVANCE:

This study challenges the practice of coprescribing OAC plus AP unless there is a clear indication for adding AP to OAC therapy in newly diagnosed atrial fibrillation.

Keywords 
anticoagulants atrial fibrillation stroke antiplatelet
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