Tetralogy of Fallot

Cardiology / Pediatrics

Overview

Definition

A cyanotic congenital heart defect characterized by four classic anomalies: ventricular septal defect (VSD), pulmonary stenosis, right ventricular hypertrophy, and overriding aorta.

Epidemiology

The most common cyanotic congenital heart disease in newborns.

Etiology & Risk Factors

  • Anterosuperior deviation of the infundibular septum during embryogenesis
  • Association with DiGeorge Syndrome (22q11 deletion)

Clinical Symptoms

  • Cyanosis ('blue baby')
  • 'Tet spells' (hypercyanotic episodes triggered by crying/feeding, relieved by squatting)
  • Systolic ejection murmur at left sternal border
  • Clubbing of fingers

Clinical Approach

Diagnosis

  • Echocardiography
  • Chest X-Ray showing a classic 'boot-shaped heart' (due to RV hypertrophy and small pulmonary artery)

Management

  • Surgical correction (VSD closure and pulmonary valve relief) in infancy
  • Oxygen, knee-to-chest position, and beta-blockers for Tet spells

Complications

  • Arrhythmias
  • Sudden death
  • Right heart failure
  • Infective endocarditis