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Congenital cardiac malformations in relation to central venous access.

During the third and seventh weeks of gestation, teratogenic exposure may lead to fetal abnormality such as congenital heart defects or intrauterine death. Congenital heart defects are present from birth, but may appear at any time, or only revealed postmortem. Often defects are present by degree. Some defects are life-threatening, while other, less severe conditions, may have minimal physiological impact. Left superior vena cava exists in early embryonic development, but the vessel degenerates as the cardiovascular system matures. When not associated with other malformations, an incidence of persistent left-sided superior vena cava (PLSVC) has no clinical signs or symptoms. However, it may not be as innocuous as it appears due to its association with the cyanotic defect, tetralogy of Fallot (TOF). Using a case history as an illustration it can be shown that all cases of defect or chromosomal suspicion should be documented as there may be implications for future interventions.