Late outcomes in adults with atrial switch for transposition of the great arteries according to risk factor profile at 30 years of age

Objective

To compare the late outcomes of adults who underwent atrial switch repair for dextro-transposition of the great arteries, based on their risk profile at age 30 years.

Methods

We performed a retrospective study of 67 participants who had undergone atrial switch repair. “Low risk” people were defined as those who reached age 30 years or beyond with normal or mildly impaired systemic right ventricular (RV) function with no or mild tricuspid regurgitation (TR). “High risk” people were defined as those who had moderate or severe systemic RV dysfunction, or moderate or severe tricuspid regurgitation by age 30. The primary outcome was transplant-free survival and the secondary outcome was a composite end-point including hospitalisations for heart failure, inotrope requirement, referral for transplantation and transplantation.

Results

52/67 (78%) were classified as “low risk” and 15/67 (22%) were classified as “high risk”. At 45 years, transplant-free survival was 31% for the “high risk” group compared to 87% for “low risk”. All “high risk” people met the composite endpoint at 45 years compared to only 18% of the “low risk” group (hazard ratio 6.3, p = 0.03).

Conclusion

Transplant-free survival is markedly reduced in “high risk” atrial switch patients. Risk stratification based on systemic right ventricular function and tricuspid regurgitation at age 30 may predict future health outcomes for atrial switch patients.