Diagnostic Workup for Lacunar Stroke

Initial Acute Phase Imaging

• Non-contrast CT head is mandatory initially to exclude intracranial hemorrhage and evaluate for early ischemic changes, regardless of suspected stroke subtype, as recommended by the American College of Radiology 1, 2
• Vascular imaging (CTA or MRA) must be obtained urgently to exclude large vessel occlusion, even when lacunar stroke is suspected clinically, because NIHSS scores correlate poorly with LVO presence, according to the American College of Radiology 1, 3

Comprehensive Secondary Prevention Workup

Cardiac Evaluation Required

• Transthoracic echocardiography at minimum to assess for cardioembolic sources, as recommended by the American Heart Association/American Stroke Association 4
• Extended cardiac rhythm monitoring to detect paroxysmal atrial fibrillation, as recommended by the American Heart Association/American Stroke Association 4

Vascular Assessment

• Carotid imaging (duplex ultrasound, CTA, or MRA) within 48 hours to exclude ipsilateral large-artery stenosis >50%, as recommended by the American Heart Association/American Stroke Association and the American College of Radiology 4, 2

Laboratory Studies

• Lipid profile and hemoglobin A1c are essential components of the diagnostic assessment, as recommended by the American Heart Association/American Stroke Association 4

Important Clinical Caveats

• Misclassification of lacunar stroke has therapeutic implications: a patient with atrial fibrillation and a small subcortical infarct requires anticoagulation, not just antiplatelet therapy, as recommended by the American Heart Association/American Stroke Association 4
• The clinical syndrome alone is insufficient for diagnosis—imaging confirmation of infarct size and location plus exclusion of alternative causes is mandatory, as recommended by the American Heart Association/American Stroke Association 4

Subacute Lacunar Infarct: Definition and Clinical Implications

Characteristics of Lacunar Infarcts

• Lacunar infarcts are subcortical strokes measuring <1.5 cm in diameter on CT or MRI without evidence of a concomitant cortical infarct 5
• Most lacunar infarcts are due to small vessel disease affecting penetrating arteries deep in the brain or brain stem 5

Clinical Presentation

• Patients typically present with one of the classical lacunar syndromes, such as pure motor hemiparesis 6

Pathophysiology

• Unlike other stroke subtypes, lacunar infarcts are generally not caused by atherosclerosis but rather by a distinct arteriopathy of small vessels 6, 7

Prognosis

• Among stroke subtypes, patients with small-artery occlusion have the highest survival rate (85% at 2 years) compared to other stroke subtypes 7, 8

Diagnostic Considerations

• Diagnosis requires neuroimaging (CT or MRI) showing a small (<1.5 cm) subcortical infarct 5, 9
• Potential sources of cardioembolism and ipsilateral large-artery stenosis should be excluded to confirm the diagnosis of lacunar stroke 7

Lacunar Stroke and Related Subcortical Infarctions

Definition and Diagnosis

• Lacunar strokes are small (<1.5 cm) subcortical infarcts caused primarily by small vessel disease, located in the basal ganglia, brain stem, or deep white matter, with a size criterion of <1 cm in maximal dimension, according to the American Heart Association 10
• The prognosis for lacunar strokes is the best among stroke subtypes, with an 85% survival rate at 2 years and lower early mortality and recurrence rates, as reported by the American Stroke Association 11
• Pure sensory stroke is a clinical presentation of lacunar stroke, as noted by the American College of Physicians 12

Management and Treatment

• The American Heart Association recommends antiplatelet therapy and aggressive risk factor modification for patients with small vessel disease confirmed, with a blood pressure target of <130 mmHg systolic 13
• Anticoagulation is required for patients with cardioembolism identified, regardless of small infarct size, as stated by the American College of Cardiology
• The management of lacunar strokes and related subcortical infarctions should be based on the underlying mechanism, with small vessel disease treated with antiplatelet therapy and cardioembolism treated with anticoagulation, according to the European Stroke Organisation 10, 11, 13