Impact of Atretic Aortic Valve on Systemic Ventricular Function After the Norwood Procedure.

BACKGROUND

Aortic atresia (AA) is considered a risk for the Norwood procedure. This study aimed to compare the longitudinal ventricular function (VF) and atrioventricular valve (AVV) regurgitation in patients with AA and aortic stenosis (AS).

METHODS

Using serial echocardiographic images in patients undergoing the neonatal Norwood procedure between 2001 and 2020, systemic VF assessed by ejection fraction and the degree of AVV regurgitation were compared between the patients with AA and AS.

RESULTS

A total of 335 consecutive patients were included, consisting of 273 with hypoplastic left heart syndrome and 62 with its variants. AA was observed in 146 patients (43.6%) and AS in 189 (56.4%). Longitudinal VF and AVV regurgitation were evaluated using a total of 4687 echocardiograms. Preoperatively, VF was better in AA patients than in AS patients (P = .01). After the Norwood procedure, VF was initially (1-30 days) worse in patients with AA than in those with AS (P < .01). However, after that (31 days to stage 2 palliation), it improved in the AA group but remained worse than in the AS group (P < .01). After stage 2 palliation, VF was reduced in the AA group compared to the AS group, especially between 31 to 90 days postoperatively (P < .01). The degree of AVV regurgitation after the Norwood procedure (P < .01) as well as after stage 2 palliation (P < .01), was worse in AA patients, compared with AS patients.

CONCLUSIONS

After the Norwood procedure, patients with AA demonstrated inferior systemic VF as well as worse AVV function throughout the palliation period before Fontan completion.