Abstract

Transposition of the great arteries (TGA) is a rare congenital heart defect incompatible with life without surgical correction. This report presents a 25-year-old male patient who underwent the Mustard procedure for d-TGA in the neonatal period. The patient presented with chest discomfort, exertional dyspnea, and fatigue. A grade II/VI pansystolic murmur was noted, and investigations revealed right ventricular hypertrophy, mild cardiomegaly, and moderate pulmonary venous baffle obstruction (mean gradient: 14 mmHg). Treatment with carvedilol and aspirin was initiated, and the patient is followed up biannually. TGA involves ventriculo-arterial discordance, corrected with arterial switch or Mustard procedures. Adults surviving the Mustard procedure remain at risk of early death, heart failure, and arrhythmias. This case highlights the 25-year follow-up of a stable d-TGA patient after the Mustard procedure, emphasizing the importance of regular monitoring for long-term outcomes.