Echocardiography versus CMR in Pulmonary Regurgitation Assessment Post-Surgical Fallot Repair

Background: Tetralogy of Fallot (TOF) is the most prevalent congenital cyanotic cardiac condition. Treatment is surgical. Pulmonary regurgitation and right-sided heart failure following TOF repair are common. Regular right ventricular volume assessment post-repair using cardiac magnetic resonance (CMR) imaging, the validated diagnostic tool, is essential to detect complications early. However, CMR is limited in availability, expensive, and sometimes contraindicated. Objective: Our study aimed to evaluate the pulmonary regurgitation using transthoracic echocardiography (TTE) and compare its results with CMR in post-Fallot tetralogy repair children. Patients and Methods: This cross-sectional study was conducted at the Pediatric Cardiology Department at Cairo University Hospitals. We included thirty-six children of Fallot tetralogy repair from Cardiology clinic attendees. All children were subjected to complete history taking, clinical examination, CMR imaging results from their files, and TTE. Results: The pulmonary regurgitation percentage as determined by CMR and the pulmonary regurgitation diameter to pulmonary valve annulus ratio as determined by echocardiography showed a strong Kappa agreement. The accuracy of echocardiography was 58.3%, the sensitivity was 100%, the specificity was 25%, the positive predictive value was 51.6%, and the negative predictive value was 100%. The pulmonary regurgitation fraction as determined by CMR and the pulmonary regurgitation index as determined by echocardiography showed a strong Kappa agreement. The accuracy of the pulmonary regurgitation index was 75%, the sensitivity was 81.3%, the specificity was 70%. Conclusions: Echocardiography remains a valuable screening tool for PR assessment post-TOF repair, but CMR provides superior quantification of PR fraction and RV volumes.