Perioperative prediction of adverse events with age-adjusted NT-proBNP in children undergoing Norwood surgery.

Abstract

Background: Due to the high postoperative mortality, tools for an adaequate risk stratification are important to identify high-risk patients undergoing the Norwood procedure. As a marker of ventricular wall stress, NT-proBNP might be of particular interest in these children.

Objectives: This study evaluated whether NT-proBNP's age-adjusted z-score ("zlog-NT-proBNP") predicts outcomes after stage I Norwood procedure.

Methods: Patients who underwent the Norwood procedure between 1 January 2011 and 31 December 2022, with perioperative NT-proBNP measurements available were enrolled. Since reference intervals of NT-proBNP are highly age-dependent, age-adjusted zlog-NT-proBNP was used. Serial zlog-NT-proBNP values were analysed to predict the occurrence of major adverse cardiovascular events after the Norwood procedure. Major adverse cardiovascular events was defined as death, resuscitation, or mechanical circulatory support. Secondary endpoints were re-operation and re-intervention for shunt.

Results: A total of 139 patients underwent the Norwood procedure and had at least one NT-proBNP measurement available. Preoperative zlog-NT-proBNP measurements (median 3.7, interquartile range 3.1-4.19) showed no association with the occurrence of major adverse cardiovascular events or mortality. Zlog-NT-proBNP early after ICU admission (3.2, interquartile range 2.4-3.8) was predictive of mortality but showed no association with the occurrence of major adverse cardiovascular events. Zlog-NT-proBNP before ICU discharge (3.2, interquartile range 2.8-3.8) was significantly associated with the occurrence of both major adverse cardiovascular events (hazard ratio 1.83, 95% confidence interval 1.25-2.67, P = 0.002) and death (hazard ratio 2.1, 95% CI 1.4-3.2, P < 0.001).

Conclusions: High zlog-NT-proBNP levels after the Norwood surgery were strongly associated with the occurrence of major adverse cardiovascular events and death. Therefore, zlog-NT-proBNP has the potential to identify high-risk patients before life-threatening complications occur.