Congenital lung malformation can easily be diagnosed by prenatal ultrasound. Associated extrapulmonary malformations such as heart defects and chromosomal aberrations are rare.OBJECTIVE: The objective of this study was to describe the natural history, outcome and other associated malformations in fetuses with lung lesions and an associated heart defect. METHODS: Retrospective analysis of 4 cases of prenatally diagnosed fetal CCAMs and hybrid lesions with an associated heart defect and review of 8 cases in the literature. RESULTS: At a single referral center 1.9% of the fetuses with Congenital cystic adenomatoid malformation (CCAM) were diagnosed with an associated heart defect. Seven of the total 12 cases (58%) reviewed had a conotruncal heart abnormality. Chromosomal abnormalities were found in 5 (42%) of the cases. CONCLUSION: This retrospective review shows that karyotyping in fetal lung lesions with an associated heart defect or isolated large lung lesions is indicated. It also suggests that there is a subpopulation of fetuses with CCAMs who have conotruncal heart defects. This finding may suggest a common genetic background.