Evaluating the value of lung to heart ratio in prognosis and prenatal diagnosis of congenital diaphragmatic hernia via ultrasound

Abstract

Incidence of congenital diaphragmatic hernia is 0.8-5/10,000 live birth, frequently recorded on the left side. This malformation owned a high rate of mortality and morbidity perinatally. Objective: To evaluate the value of lung to heart ratio (LHR) including observed LHR (oLHR) and observed/expected LHR (o/eLHR) in prognosis and prenatal diagnosis of congenital diaphragmatic hernia via ultrasound. Methodology: This is a restrospective study in 99 pregnant women who were diagnosed with diaphragmatic hernia in Center for Prenatal diagnosis. Observed and Observed/expected Lung to heart ratio were recorded in those cases. Results: oLHR in group of maintained pregnancy was significantly higher than that in group of selective abortion (1.22±0.60 vs 0.78±0.3; p<0.001). o/eLHR in group of maintained pregnancy was also statistically higher in selective abortion (0.30±0.12 vs 0.26+0.11; p>0.05). Among stable newborns, mean of oLHR was 1,6 versus 0,37 in mortality group (p<0.001). According to ROC curve, perinatal outcomes could be prognosed via oLHR and o/eLHR. oLHR cut-off was 1.2 with sensitivity of 76.9% and specificity of 93.7% and AUC was 83.2% (p<0.0001). o/eLHR cut-off was 0.29 with 84.6% sensitivity and 87.5% specificity and AUC of 83.9% (p<0.001). Conclusion: Lung-to-heart ratio was valuable in prognosis and prenatal diagnosis of diaphragmatic hernia.