Embolic Stroke of Undetermined Source (ESUS): Exploring the Neurocardiological Axis and Its Clinical Implications

Area of Science:

• Neurology
• Cardiology
• Stroke Medicine

Background:

• Embolic stroke of undetermined source (ESUS) is a clinical category for cryptogenic ischemic strokes lacking a clear cause.
• ESUS represents approximately 17% of ischemic strokes, often affecting younger individuals with fewer traditional risk factors.
• The initial hypothesis suggested anticoagulation might be superior to antiplatelet therapy for secondary prevention in ESUS patients.

Purpose of the Study:

• To review current knowledge and clinical trial outcomes regarding Embolic stroke of undetermined source (ESUS).
• To evaluate the efficacy of anticoagulants versus antiplatelet therapy in secondary stroke prevention within the ESUS population.
• To discuss the implications of recent trial findings on the ESUS diagnostic and therapeutic framework.

Main Methods:

• Synthesis of current knowledge on Embolic stroke of undetermined source (ESUS).
• Review of major clinical trials including NAVIGATE ESUS, RE-SPECT ESUS, and ARCADIA.
• Analysis of patient demographics, risk factors, and covert embolic substrates in ESUS.

Main Results:

• Major clinical trials (NAVIGATE ESUS, RE-SPECT ESUS, ARCADIA) found no significant benefit of anticoagulants over aspirin for secondary prevention in ESUS.
• ESUS patients often have covert embolic substrates despite lacking major cardioembolic sources or significant arterial stenosis.
• The efficacy of the established ESUS framework is challenged by the negative trial outcomes.

Conclusions:

• The original hypothesis regarding anticoagulation superiority in ESUS is not supported by current evidence from major trials.
• The heterogeneity within the ESUS population necessitates individualized diagnostic and therapeutic approaches.
• Further research is needed to refine diagnostic criteria and treatment strategies for cryptogenic strokes.