Ventricular Fibrillation (VF)

Overview


Plain-Language Overview

Ventricular fibrillation (VF) is a serious heart condition where the lower chambers of the heart, called ventricles, start to quiver instead of pumping blood properly. This affects the heart's electrical system, which controls the heartbeat. Because the ventricles cannot pump blood effectively, the body’s organs, including the brain, do not get enough oxygen-rich blood. This can cause sudden loss of consciousness and is a life-threatening emergency. The main problem is that the heart rhythm becomes chaotic and irregular, preventing normal blood flow. Immediate medical attention is critical to restore a normal heartbeat and prevent death.

Clinical Definition

Ventricular fibrillation (VF) is a life-threatening cardiac arrhythmia characterized by rapid, erratic electrical impulses in the ventricles leading to ineffective quivering rather than coordinated contraction. It results from disorganized depolarization of ventricular myocardium, commonly triggered by ischemic heart disease, acute myocardial infarction, or electrolyte imbalances. The hallmark of VF is the loss of effective cardiac output, causing sudden cardiac arrest. It is a primary cause of sudden cardiac death and requires immediate intervention. On electrocardiogram, VF shows irregular, chaotic waveforms without identifiable QRS complexes. The pathophysiology involves multiple reentrant circuits and abnormal automaticity within ventricular tissue. Prompt recognition and treatment are essential to prevent irreversible organ damage.

Inciting Event

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Clinical Presentation


Signs & Symptoms

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History of Present Illness

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Past Medical History

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Family History

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Physical Exam Findings

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Diagnostic Workup


Diagnostic Criteria

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Pathophysiology


Key Mechanisms

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Treatments


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Prevention


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Non-pharmacological Prevention

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Outcome & Complications


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Differential Diagnoses


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