Pulmonary valve annular and right ventricular outflow tract size as predictions values for moderate to severe pulmonary regurgitation after repaired Tetralogy of Fallot.

Objective: This study sought to investigate the variation of right heart structure pre- and post-operation as risk factors for moderate to severe pulmonary regurgitation (PR) after repaired Tetralogy of Fallot and the best "cutoff" values for the transannular patch (TAP).

Methods: We collected surgical, echocardiographic, and computed tomographic data of Teralogy of Fallot (TOF) patients over two years and calculated z-score values based on the echocardiographic data. Based on the PR level after follow-up, the patients were divided into two groups, trivial to mild PR and moderate to severe PR. A multivariate logistic regression analysis was performed, and the receiver operating characteristic curve analysis was used to find the best "cutoff" value for risk factors.

Results: A total of 104 TOF patients were included in our cohort study. From the multivariate analysis, correction strategy (P = .002), difference in zRVOT (OR 1.974, 95% CI 1.354 to 2.878, P < .0001), and zPVA (OR 3.605, 95% CI 1.980 to 6.562, P < .0001) were the significant risk factors for moderate to severe PR. The "cutoff" value for the difference in zPVA that could predict moderate to severe PR in the TAP group was 3, and the optimal "cutoff" value for TAP was -1.4.

Conclusions: The TAP is a risk factor for significant PR after surgery. We recommend the optimal "cutoff" value for TAP is -1.4 calculated using Shan-Shan Wang's data set. During the procedure, to limit the RVOT resection and restrict the enlargement of pulmonary annulus within a variation of z-score as 3 would reduce significant PR.