Defining Expectations for Infants With Hypoplastic Left Heart Syndrome Who Survive Initial Surgical Palliation

Overall one-year non-mortality outcomes for surgically palliated hypoplastic left heart syndrome (HLHS) patients remain understudied. Using the metric Days Alive and Outside of Hospital (DAOH), the present study sought to characterize expectations for surgically palliated patients' first year of life.

The Pediatric Health Information System database was used to identify by ICD-10 code all HLHS patients who underwent surgical palliation (Norwood/hybrid and/or heart transplantation [HTx]) during their index neonatal admission and were successfully discharged alive (n  =  2227) and for whom one-year DAOH could be calculated. DAOH quartiles were used to group patients for analysis.

Median one-year DAOH was 304 (interquartile range [IQR] 250-327), including a median index admission length of stay of 43 days (IQR 28-77). Patients required a median 2 (IQR 1-3) readmissions, each spanning 9 days (IQR 4-20). One-year readmission mortality or hospice discharge occurred in 6% of patients. Patients with lower-quartile DAOH had a median DAOH of 187 (IQR 124-226), whereas upper-quartile DAOH patients had a median DAOH of 335 (IQR 331-340) (P < .001). Readmission mortality/hospice-discharge rates were 14% and 1%, respectively (P < .01). On multivariable analysis, factors independently associated with lower-quartile DAOH included interstage hospitalization (odds ratio [OR] 44.78 [95% confidence interval [CI] 25.1-80.2]), index-admission HTx (8.73 [4.66-16.3]), preterm birth (1.97 [1.34-2.90]), chromosomal abnormality (1.85 [1.26-2.73]), age >7 days at surgery (1.50 [1.14-1.99]), and non-white race/ethnicity (1.33 [1.01-1.75]).

In the current era, surgically palliated HLHS infants spend approximately 10 months alive and outside of the hospital, although outcomes are highly variable. Knowledge of the factors associated with lower DAOH can inform expectations and guide management decisions.