Detection screening and seasonality evaluation of hypoplastic left heart syndrome in the polish national registry for fetal cardiac anomalies from the years 2004 to 2016

Objectives: To evaluate the incidence of hypoplastic left heart syndrome (HLHS) and the efficiency of the screening program using data from the Polish National Registry for Fetal Cardiac Anomalies. To investigate whether HLHS incident rates in Poland are seasonally variable.

Methods: Data on 791 cases of HLHS from the Registry collected between 2004 and 2016 was analyzed.

Results: The median gestational age for the 734 cases of HLHS detected was 23 weeks. Comparing the age at time of HLHS detection between 2004 and 2016, a decrease from 26 to 20.8 weeks was observed. We noted a rapid increase in HLHS incidence during the initial years of the Registry data, the annual percentage change during that period was 22.0% and this trend lasted until 2010. In the following years, the Registry became representative of the general population which has an estimated incidence of HLHS of 20.93 cases per 100 000 live births. We observed no clear seasonal patterns of HLHS incidence in our population.

Conclusion: The Registry reached a plateau state in terms of diagnosing new cases of HLHS. No evidence of seasonality has been noted. The average gestational age of patients identified as having HLHS decreased significantly during the study period.