Background: Tetralogy of Fallot is the most common cyanotic congenital heart defect. Borderline pulmonary anatomy has been associated with a higher risk of mortality and morbidity. Strategies to manage this condition—namely, single- or multistage repair—have long been debated. Objective: The overall outcomes of patients with tetralogy of Fallot with borderline pulmonary arteries (McGoon ratio 1.3 to 1.7) with regard to the need for a single-stage or multistage repair and the outcome of each surgical management were evaluated. Patients and methods: A retrospective, nonrandomized comparative study designed to evaluate patient outcomes comprised 60 patients with tetralogy of Fallot with borderline pulmonary arteries who underwent surgery at the Cardiothoracic Surgery Academy, Ain Shams University, Cairo, Egypt, between January 2016 and December 2017. After gaining approval from the affiliated ethical and research committee, and informed consent of the guardians, the patients were assigned into one of two groups. Shunt group included 30 patients managed surgically by a modified Blalock-Taussig (MBT) shunt as a part of a multistage repair, and repair group included 30 patients managed surgically by single-stage complete repair. The medical records of the patients were reviewed, and data relating to age, sex, weight, and preoperative oxygen saturation were collected. All patients underwent preoperative echocardiography and multislice computed tomography (CT) with angiography. The follow-up was performed by echocardiography at discharge and at one month and six months after surgery. Multislice CT with angiography was performed in patients who received a shunt once the echocardiography showed acceptable pulmonary arteries. Results: The patients’ age ranged from 5 to 50 months with a mean age of 18.63 ± 9.15 (19.84 ± 12.34 for the shunt group and 17.43 ± 8.54 for the repair group). The weight ranged from 5 kg to 18 kg with a mean of 9.6 ± 2.53 (8.82 ± 2.79 for the shunt group and 10.41 ± 2.63 for the repair group). The mean preoperative O2 saturation was 68.95% ± 7.8% for the shunt group and 87.93% ± 6.18% for the repair group. The median McGoon ratio was 1.4 for the shunt group and 1.6 for the repair group, the difference of which was highly significant (P < .0001). The mortality rate in our study was 10% (10% for the shunt group and 10% for the repair group). The morbidity incidence rate was 26.6% for the shunt and repair groups. The ICU stay ranged from 2 to 31 days, with a median of three days for the shunt group (mean 3.61 ± 1.91) and four days for the repair group (mean 6.07 ± 6.63 days). The calculated P value showed a significant difference between the two groups concerning ICU stay. The postoperative SO2 significantly increased to a mean of 85.58 ± 7.05 in the shunt group and 98.14 ± 3.36 in the repair group (P < .0001). Conclusion: There was no statistically significant difference between multistage repair and single-stage complete repair regarding morbidity and mortality. Regarding ICU stay, patients in the single-stage had a better outcome. A McGoon ratio of 1.5 can be used as a guideline in the decision-making process.