What can pulmonary regurgitation indices reflect in patients after tetralogy of Fallot repair?

Abstract

Background: Residual haemodynamic complications remaining after surgical correction of tetralogy of Fallot (ToF) require regular follow-up. Aim: To establish the utility of pulmonary regurgitation (PR) indices in the routine clinical management of adults with repaired ToF. Methods: 83 consecutive patients with repaired ToF underwent transthoracic echocardiography (TTE), cardiopulmonary exercise test (CPET), cardiac magnetic resonance (CMR), and laboratory test evaluation. They were divided into two subgroups [PR (+) vs. PR (-)] according to the degree of PR fraction (PRF > 20% vs. ≤ 20%) assessed by CMR. Results: Analysis showed that PR vena contracta (PR VC) ≤ 5 mm in TTE study was 83% sensitive and 68% specific in identifying patients with PRF ≤ 20%. Furthermore, PR index (PRi) ≥ 0.73 was 85% sensitive and 43% specific in identifying patients with non-significant PR. In this group of patients, there were significant correlations of TTE parameters describing the degree of PR and right ventricle (RV) size with reference modality CMR. There was no certain influence of PR severity on RV function, physical performance, and renal or hepatic failure indices. Conclusions: PRi and PR VC are helpful parameters in distinguishing between mild and significant PR and may limit the indication for CMR investigation in a group with non-significant PR. The severity of PR in our study did not seem to have an impact on RV function, physical performance, liver or kidney function indices.