Definition

  • Historically known as Bland-White-Garland syndrome.
  • Rare congenital anomaly; Left coronary artery (LCA) arises from pulmonary artery (PA) instead of aorta.
  • Prevalence: 1 in 300,000 births.

Pathophysiology

PhaseHemodynamic AlterationClinical Consequence
NeonatalHigh pulmonary vascular resistance (PVR). Antegrade flow from PA to LCA.Asymptomatic.
1-2 MonthsPVR falls. Flow reversal (LCA to PA) causing “Coronary Steal”.Decreased myocardial perfusion.
ProgressionChronic subendocardial ischemia, infarction.Left ventricular (LV) dilation, mitral regurgitation (papillary muscle infarction).

Clinical Manifestations

Infantile Presentation (Most Common)

  • Onset typically second month of life.
  • “Infantile angina”: Irritability, diaphoresis, pallor during feeds.
  • Congestive heart failure: Dyspnea, tachypnea, failure to thrive.
  • Untreated mortality: 90% within first year.

Adult/Late Presentation

  • Depends on extensive right coronary artery (RCA) to LCA collateralization.
  • Asymptomatic, or presents with angina, syncope, ischemic cardiomyopathy, sudden cardiac death.

Diagnostic Evaluation

Electrocardiogram (ECG)

  • Anterolateral myocardial infarction pattern.
  • Deep, wide Q waves and inverted T waves in leads I, aVL, V5, V6.
  • Diminished/absent R waves in mid-precordial leads (V3, V4).

Echocardiography

  • Dilated, poorly contractile LV.
  • Mitral regurgitation.
  • Color Doppler pathognomonic finding: Retrograde flow from LCA into PA.

Confirmatory Imaging

  • CT Angiography (CTA), MRI, or invasive coronary angiography (Gold Standard) defines anomalous origin and collateral extent.

Management

Medical Stabilization

  • Heart failure therapy (diuretics, ACE inhibitors, beta-blockers) serves only as short-term bridge.

Surgical Repair (Definitive)

  • LCA Reimplantation: Direct coronary button transfer to ascending aorta (Procedure of choice).
  • Takeuchi Procedure: Intrapulmonary baffle creation connecting aorta to anomalous LCA ostium (utilized if direct translocation impossible).
  • CABG: LIMA or vein graft with LCA ostial ligation.
  • Prognosis excellent post-repair; LV function typically normalizes completely.