Bland-White-Garland Syndrome

Bland-White-Garland Syndrome (BWGS)

Bland-White-Garland Syndrome, also known as Anomalous Left Coronary Artery from the Pulmonary Artery (ALCAPA), is a rare congenital heart defect. It occurs in approximately 1 in 300,000 live births and accounts for 0.25-0.5% of all congenital heart diseases.

Key Points:

  • Rare congenital anomaly where the left coronary artery originates from the pulmonary artery instead of the aorta
  • Results in myocardial ischemia and potential infarction
  • Typically presents in infancy, but can rarely be diagnosed in adults
  • Surgical correction is the definitive treatment

Pathophysiology

The abnormal origin of the left coronary artery leads to several pathophysiological changes:

  1. Myocardial Ischemia: Low oxygen content in pulmonary arterial blood causes inadequate perfusion of the left ventricle.
  2. Coronary Steal Phenomenon: Blood flows from the right coronary artery to the left coronary system and then into the pulmonary artery, further depriving the myocardium of oxygenated blood.
  3. Collateral Circulation: Development of collaterals between right and left coronary systems may provide some protection but is often insufficient.
  4. Left Ventricular Dysfunction: Chronic ischemia leads to left ventricular dilatation and dysfunction.
  5. Mitral Regurgitation: Can occur due to papillary muscle dysfunction from ischemia.

Clinical Presentation

Symptoms typically appear within the first few months of life as pulmonary vascular resistance decreases.

Infant Presentation:

  • Failure to thrive
  • Irritability, especially during feeding
  • Diaphoresis
  • Tachypnea
  • Pallor
  • Signs of congestive heart failure

Adult Presentation (Rare):

  • Dyspnea on exertion
  • Angina
  • Palpitations
  • Syncope
  • Sudden cardiac death

Physical Examination:

  • Systolic murmur at the left sternal border (mitral regurgitation)
  • Gallop rhythm
  • Hepatomegaly
  • Tachycardia
  • Signs of heart failure (rales, edema)

Diagnosis

Diagnosis of BWGS requires a high index of suspicion and is confirmed through various imaging modalities:

Diagnostic Tools:

  1. Electrocardiogram (ECG):
    • Deep Q waves in leads I, aVL, V5-V6
    • ST-segment and T-wave changes indicating ischemia
    • Left ventricular hypertrophy
  2. Chest X-ray:
    • Cardiomegaly
    • Pulmonary congestion
  3. Echocardiography:
    • Dilated left ventricle with reduced function
    • Mitral regurgitation
    • Abnormal origin of left coronary artery
    • Retrograde flow in left coronary artery
  4. Cardiac CT or MRI:
    • Definitive imaging of coronary anatomy
    • Assessment of myocardial viability
  5. Cardiac Catheterization:
    • Gold standard for diagnosis
    • Demonstrates abnormal origin of left coronary artery
    • Shows collateral circulation

Treatment

The definitive treatment for BWGS is surgical correction. Medical management is used as a bridge to surgery in infants with severe presentation.

Medical Management:

  • Inotropic support (e.g., dobutamine, milrinone)
  • Diuretics for heart failure symptoms
  • Afterload reduction with ACE inhibitors
  • Mechanical ventilation if necessary

Surgical Options:

  1. Direct Reimplantation: Preferred method when anatomically feasible. The left coronary artery is detached from the pulmonary artery and reimplanted into the aorta.
  2. Takeuchi Procedure: Creation of an intrapulmonary tunnel that connects the aorta to the anomalous left coronary artery.
  3. Coronary Artery Bypass Grafting (CABG): Used in some adult cases or when direct reimplantation is not possible.

Post-operative Care:

  • Close monitoring in ICU
  • Gradual weaning from inotropic support
  • Echocardiographic follow-up to assess ventricular function
  • Long-term follow-up for potential complications (e.g., coronary stenosis, arrhythmias)


Further Reading
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