Cardiac MRI in surgically repaired tetralogy of Fallot: Our initial experience

Pulmonary regurgitation (PR) required pulmonary valve replacement (PVR) is usually seen after surgically repaired tetralogy of Fallot (TOF). Assessment by cardiac magnetic resonance imaging (CMR) plays a crucial role in the decision of PVR. Herein, we presented our 3-year interdisciplinary CMR experience in the assessment of repaired TOF.

CMR examinations of 196 patients with repaired TOF performed between 2016 and 2018 were enrolled in this retrospective study. Only 165 were included in the study. CMR findings were assessed according to the American College of Cardiology/American Heart Association guideline and recommendations of Geva.

Among those 165 patients (median age 14 years [mean age 15.62±7.42 years], M/F=114/61; 1.86/1), 73 patients were found eligible for PVR (59 patients for transcatheter while 14 patients for surgical). The mean QRS duration was 170.2±16.89 ms. On CMR assessment, mean indexed right ventricular end-diastolic volume, end-systolic volume, right, and left ventricular ejection fraction were 187.64±45.07 ml/m², 39.90±6.60%, and 47.83±6.12%, respectively. The PR fraction was as 50.10±2.54% and 2.25±1.92. Balloon dilatation and/or stenting of branch pulmonary arteries in 12 patients and ventricular septal defect closure in four patients were performed at the same session of percutaneous PVR. At the time of the surgical PVR, repair of partial anomalous pulmonary venous return in one patient, ventricular septal defect in two patients, and subaortic membrane in one patient were performed. An implantable cardioverter-defibrillator was also performed in one patient.

Our CMR experience has the largest patient population in our country and may contribute to the national data pool. We believe that our collaborative experience between radiologists, cardiologists, and cardiovascular surgeons may also enhance the use of CMR in determining the appropriate technique or timing for PVR.