Systemic Venous Drainage Is Associated with an Unfavorable Prenatal Behavior in Fetal Bronchopulmonary Sequestration

Outcome of fetal congenital pulmonary malformations: a systematic review and meta-analysis

OBJECTIVES

To report the outcome of fetuses with a prenatal diagnosis of congenital lung malformation (CLM) diagnosed on ultrasound by performing a comprehensive assessment of these outcomes through a systematic review and meta-analysis.

CONTENT

CLMs are a heterogeneous group of anomalies that involve the lung parenchyma and its bronchovascular structures. Their presentation and evolution are variable, from entirely asymptomatic lesions with sonographic regression in utero to hydropic fetuses requiring fetal therapy, intrauterine death or neonatal morbidity. A systematic review was conducted in Medline, Embase and Cochrane databases including studies on fetuses with CLM diagnosed prenatally in order to report the in-utero natural history of these lesions. Thirty-nine studies (2,638 fetuses) were included in the final review.

SUMMARY

Regression/reduction in size of the lung lesion during pregnancy was reported in 31 % of cases, while its increase in 8.5 % of cases. Intra-uterine death complicated 1.5 % of pregnancies with fetal CLM, while neonatal and perinatal death were 2.2 and 3 %, respectively. Neonatal morbidity occurred in 20.6 % of newborns with CLM; 46 % had surgery, mainly elective. In fetuses with CLM and hydrops, fetal/perinatal loss occurred in 42 %. Assessment of the role of fetal therapy in improving the outcomes of pregnancies complicated by CLM was hampered by the small number of included cases and heterogeneity of type of interventions.

OUTLOOK

Fetuses with CLM prenatally diagnosed have a generally favorable outcome. Conversely, there is a low quality of evidence on the actual role of fetal therapy in improving the outcome of fetuses presenting with these anomalies.

The Utility of the Congenital Pulmonary Airway Malformation-Volume Ratio in the Assessment of Fetal Echogenic Lung Lesions: A Systematic Review

Although relatively uncommon, the incidence of fetal echogenic lung lesions - a heterogeneous group of anomalies that includes congenital pulmonary airway malformations (CPAM) and bronchopulmonary sequestrations (BPS) - has increased recently. Two decades ago, the CPAM-volume ratio (CVR) was first described as a tool to predict the development of hydrops, with this outcome found to be unlikely in fetuses with CVRs of ≤1.6 cm2. Since then, no clear international consensus has evolved as to the optimal CVR thresholds for the prediction of fetal/neonatal outcomes. This systematic review aimed to assess all original research studies that reported on the predictive utility of the CVR. Potentially relevant papers were identified through searching for citations of the paper that originally described the CVR, in addition to keyword searches of electronic databases. Fifty-two original research papers were included in the final review. Of these, 34 used the CVR for descriptive purposes only, 5 assessed the validity of established thresholds in different populations, and 13 proposed new thresholds. The evidence identified in this review would suggest that a threshold much lower than 1.6 cm2 is likely to be of greater utility in most populations for many outcomes of perinatal relevance. For neonatal outcomes (mostly respiratory compromise at birth), a CVR on the initial ultrasound scan ranging from 0.5 to 1.0 cm2 appears to have the greatest predictive value. Although a number of studies concurred that 1.6 cm2 was a useful threshold for the prediction of hydrops, many others were unable to assess this due to the rarity of this complication. For this reason, thresholds as low as 0.4 cm2 may be more useful for the prediction of a broader range of fetal concerns, including mediastinal shift and fluid collections. Further large-scale studies are required to determine the true utility of this well-established index.