What are the symptoms of a lacunar infarct (lacunar stroke) on the left side?

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From the Guidelines

Lacunar infarctions on the left side typically present with distinct neurological symptoms, including right-sided weakness or numbness, difficulty speaking or understanding language, coordination problems, and sensory disturbances, which require prompt medical attention and management with antiplatelet therapy and risk factor control. The symptoms of lacunar infarction on the left side can vary depending on the specific brain region affected, but common symptoms include:

  • Right-sided weakness or numbness, particularly affecting the face, arm, or leg
  • Difficulty speaking or understanding language, if language centers are involved
  • Coordination problems, unsteady gait, or clumsiness in the right limbs
  • Sensory disturbances like tingling or decreased sensation on the right side of the body These symptoms are caused by the blockage of small penetrating arteries, often resulting in "pure motor" or "pure sensory" syndromes, as noted in studies on ischemic stroke subtypes 1. Lacunar infarcts occur due to small vessel disease, commonly associated with hypertension, diabetes, smoking, or hyperlipidemia, and are classified as Small-Artery or Lacunar Stroke, which has a lower cardiac risk compared to other ischemic stroke subtypes 1. Management of lacunar infarction involves early treatment with antiplatelet therapy, such as aspirin 81-325mg daily or clopidogrel 75mg daily, along with risk factor management to prevent further strokes, and long-term management focuses on controlling vascular risk factors through medication and lifestyle modifications.

From the Research

Symptoms of Lacunar Infarction on the Left Side

  • Lacunar infarcts or small subcortical infarcts result from occlusion of a single penetrating artery and account for one quarter of cerebral infarctions 2
  • Patients with a lacunar infarct usually present with a classical lacunar syndrome, which includes:
    • Pure motor hemiparesis
    • Pure sensory syndrome
    • Sensorimotor stroke
    • Ataxic hemiparesis
    • Dysarthria-clumsy hand 2
  • Hypertension and diabetes mellitus are major risk factors for lacunar stroke, with hypertension being a significant determinant of multiple lacunar infarcts 3, 4
  • The symptoms of lacunar infarction on the left side may include:
    • Weakness or numbness on the right side of the body (due to the left hemisphere's control over the right side of the body)
    • Difficulty with speech or language (if the infarct occurs in the left hemisphere's language centers)
    • Difficulty with coordination or balance (if the infarct occurs in the left hemisphere's motor control areas)
  • Lacunar infarcts show a paradoxical clinical course with a favorable prognosis in the short term, but with an increased risk of death, stroke recurrence, and dementia in the mid- and long term 2

Risk Factors and Outcomes

  • Risk factors for lacunar infarction include:
    • Hypertension
    • Diabetes mellitus
    • Current smoking
    • Lack of physical exercise 3
  • Patients with lacunar infarcts and concurrent embolic lesions may have a worse functional outcome and be more severely affected than those with lacunar infarcts only 5
  • Combination therapy with calcium channel blockers, angiotensin-converting enzyme inhibitors, and beta-blockers may be beneficial in reducing the risk of deterioration and unfavorable outcomes in patients with lacunar infarcts 6

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Lacunar stroke.

Expert review of neurotherapeutics, 2009

Research

Antihypertensive Therapy in the Acute Phase of Lacunar Infarcts.

Medical science monitor : international medical journal of experimental and clinical research, 2018

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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