Decline in ventricular function and clinical condition after Mustard repair for transposition of the great arteries (a prospective study of 22-29 years)

BACKGROUND: Great concern exists about the ability of the anatomic right ventricle to sustain the systemic circulation in patients with transposition of the great arteries who have undergone a Mustard procedure. A prospective study was made to examine long-term survival, clinical outcome, and right ventricular function 25 years after surgery.

METHODS: Ninety-one consecutive patients underwent the Mustard procedure between 1973 and 1980. After 14 years and again after 25 years (range 22-29 years), patients were studied with ECG, echocardiography, exercise testing, and Holter monitoring.

RESULTS: The cumulative survival and event-free survival were 77% and 36%, respectively, after 25 years. Reoperation was necessary in 46%. No major loss of sinus rhythm was found. While all patients had good right ventricular function 14 years after repair, 61% of patients showed moderate-to-severe dysfunction after 25 years, when studied by echocardiography. Furthermore, the QRS complex widened and exercise capacity decreased.

CONCLUSION: The anatomic right ventricle appears to be unable to sustain the systemic circulation at long-term follow-up and the clinical condition of patients late after Mustard repair is declining. We can expect more deaths or need for heart transplantation in the next decade.