Late-Onset Pulmonary Hypertension After The Atrial Switch Procedure For Transposition Of The Great Arteries

Background: Pulmonary hypertension (PH) is one of the complications that can occur after the atrial switch procedure for transposition of the great arteries (TGA). This study aimed to assess the characteristics and prognosis of late-onset PH after the atrial switch procedure using catheterization data.Methods and Results: We retrospectively identified 40 patients with TGA after the atrial switch procedure that underwent catheterization between April 2007 and March 2020. Eligible patients were divided into two groups based on PH presence (PH group, n = 13 [33%]; non-PH group, n = 27 [67%]). Adverse events were defined as cardiac death and heart failure. Of the included patients, 63% were male, the mean (+/- standard deviation [SD]) age was 34.3 +/- 8.8 years, and 43% had Mustard operations. During the follow-up period (mean +/- SD, 4.3 +/- 3.5 years), adverse events were significantly more common in the PH group than in the non-PH group (hazard ratio 4.5, 95% confidence interval 0.99-23.0, log-rank p = 0.032). There were five patients who underwent catheterization twice during the follow-up period. Two of the five patients who had post capillary PH had improved PH and New York Heart Association (NYHA) class due to appropriate early treatment initiation for heart failure, which included diuretics, angiotensinconverting-enzyme inhibitor/angiotensin II receptor blocker, and beta-blockers.Conclusions: PH is very prevalent in adults with TGA who underwent the atrial switch procedure and is associated with an adverse prognosis. Early appropriate therapy might improve PH and NYHA class after the atrial switch procedure.