Outcomes of Norwood procedure with hypoplastic left heart syndrome: Our 12-year single-center experience

Background: In this study, we aimed to analyze the predictors and risk factors of mortality in patients who underwent Norwood I procedure with the diagnosis of hypoplastic left heart syndrome. Methods: Between January 2009 and December 2020, a total of 139 patients (95 males, 44 females) who underwent Norwood I procedure with the diagnosis of hypoplastic left heart syndrome in our center were retrospectively analyzed. Results: The median birth weight was 3,200 (range, 3,000 to 3,350) g and the median age at the time of operation was seven (range, 5 to 10) days. Pulmonary flow was achieved with a Sano shunt in the majority (72%) of patients. Survival rate was 41% after the first stage. Reoperation for bleeding (p=0.017), reoperation for residual lesion (p=0.011), and postoperative peak lactate level (p=0.029), were associated with in-hospital mortality. Nineteen (33%) of 57 patients died before the second stage. Thirty-three (58%) patients underwent second stage, and survival after the second stage was 94%. Thirteen patients underwent third stage, and survival after the third stage was 85%. Estimated probability of survival at six months, and one, two, three, and four years were 33%, 33%, 25%, 25%, and 22% respectively. Conclusion: Hospital and inter-stage mortality rates are still high and this seems to be the most challenging period in term of survival efforts of the patients with hypoplastic left heart syndrome. Early recognition and reintervention of anatomical residual defects, close follow-up in the inter-stage period, and the accumulation of multidisciplinary experience may help to improve the results to acceptable limits.