BACKGROUND: Rates of reintervention (RI) after patch-augmented reconstruction for hypoplastic aortic arch (HAA) remain moderately high. We analyzed mid-term outcomes of aortic arch reconstruction to define modifiable reintervention risk factors. METHODS: Excluding Damus-Kaye-Stansel anastomoses and previous arch repair, 338 patients underwent arch reconstruction between 2000 and 2021 at median age of 6 days (interquartile range [IQR], 4-13 days) and a median weight of 3.2 kg (IQR, 2.8-3.7 kg). Surgical technique was patch augmentation with coarctectomy with or without interdigitation in 269 patients (80%), isolated patch aortoplasty in 41 (12%), and other reconstruction in 28 (8%). Risk factors for reintervention were assessed using competing risk models. RESULTS: At median follow-up of 3.9 years (IQR, 1.1-8.0 years), 35 patients (10.4%) required reintervention (endovascular, n = 30
surgical, n = 12
both, n = 7). The 10-year cumulative incidence of death/transplant was 10% (95% confidence interval [CI], 4%-20%), and that of and reintervention was 13% (95% CI, 8%-20%). On univariate analysis, isolated patch aortoplasty (P = .002), aortic homograft patch material (P = .006), and postoperative aortic size z-score ≤-2 for each segment were associated with greater risk of reintervention: ascending aorta (P = .006), proximal (P = .001) and distal (P = .005) transverse arches, and aortic isthmus (P <
.001). On multivariable analysis, aortic homograft (hazard ratio [HR], 6.29
95% CI, 1.94-20.5
P = .002) and postoperative isthmus z-score ≤-2 (HR, 10.5
95% CI, 5.15-21.5
P <
.001) remained significant. Patients with a repaired isthmus z-score ≤-2 had a 72.8% (95% CI, 44.6-94.4%) cumulative incidence of reintervention at 10 years, versus 6.8% (95% CI, 4.1%-11.4%) in those with a z-score >
-2. CONCLUSIONS: Aortic undersizing during patch-augmented reconstruction of HAA results in a >
10% rate of reintervention at mid-term follow-up. Achieving adequate postoperative arch size is critical for preventing reintervention, with aortic isthmus size of utmost importance.