Background: The aim of this study was to evaluate the mid-term outcomes of concurrent total correction of Tetralogy of Fallot (TOF) after pulmonary valve (PV) replacement and its relation to QRS duration and MRI results.
Methods:  In this study, 51 patients with TOF who had the TOF surgery and PV replacement enrolled the study. Demographic data, MRI results such as, right ventricular end diastolic volume, right ventricular end systolic volume, systolic and diastolic indexes noted. Moreover, QRS duration and the patients' cardiac functional class were evaluated immediately before and 6 months after the surgery.
Results:  From 51 patients, 27.5% were female and 72.5% were male. The mean age of participants was 23.48 (SD=5.82) years. Functional class changes were statistically different (P<0.001) comparing the status before and after the surgery. The mean QRS duration before surgery was 130.20 (SD=16.89) ms which was in significant contrast with post-surgical states, 122.45 (SD=16.90) ms (P<0.001). Mean QRS duration before and after surgery was statistically lower in asymptomatic patients (P=0.028 and P=0.025, respectively). There was a statistical relationship between pre-surgical systolic and diastolic indexes to post-surgical functional class as asymptomatic patients had lower systolic and diastolic indexes (P=0.005 and P=0.028, respectively).
Conclusion: This study demonstrated that QRS duration before and after surgery can be an indicator to evaluate the cardiac function after surgery for Tetralogy of Fallot. Moreover, systolic and diastolic indexes are factors affecting the good prognosis of patients; therefore, PVR surgery needs to be done before the deterioration of systolic and diastolic indexes and cardiomegaly.