The palliative Mustard operation: rationale and results

Area of Science:

• Pediatric Cardiology
• Congenital Heart Disease Surgery
• Cardiovascular Physiology

Background:

• Complete transposition of the great arteries with a large ventricular septal defect often leads to severe pulmonary vascular obstructive disease.
• This condition causes reduced intercirculatory mixing, resulting in severe hypoxemia, polycythemia, and increased symptoms.
• High pulmonary arteriolar resistance ( > 10.0 units m2) makes definitive surgical correction associated with prohibitive operative mortality.

Purpose of the Study:

• To evaluate the hemodynamic benefits and outcomes of the palliative Mustard operation in patients with complete transposition of the great arteries and large ventricular septal defects.
• To assess the impact of the intraatrial baffle repair on systemic arterial saturation and hemoglobin levels.
• To determine the feasibility and effectiveness of this palliative approach in patients with high pulmonary vascular resistance.

Main Methods:

• Review of hemodynamic changes following the palliative Mustard operation (intraatrial baffle repair with an open ventricular septal defect).
• Analysis of systemic arterial saturations and hemoglobin concentrations post-operatively.
• Assessment of symptom reduction and exercise tolerance after surgery.

Main Results:

• The palliative Mustard operation can be performed with relatively low risk and provides substantial hemodynamic benefits.
• Post-operative systemic arterial saturations improved to 80-93 percent.
• Significant reduction in hemoglobin concentration towards normal levels was observed, along with reduced symptoms and increased exercise tolerance.

Conclusions:

• The palliative Mustard operation is a viable and beneficial surgical option for patients with complete transposition of the great arteries and large ventricular septal defects, especially when pulmonary vascular resistance is high.
• This procedure leads to significant hemodynamic improvement and symptomatic relief, despite the unknown long-term prognosis.
• It is crucial to understand that the outcome is not a simple reversal of preoperative saturations but a complex hemodynamic adjustment.