Fetal diagnosis - obligations of the clinician. Case studies in the prenatal diagnosis of major heart abnormality.
Fetal echocardiography allows for accurate diagnosis of major heart abnormalities by 16-18 weeks. The parents have up to 22 weeks to consider possible termination. What are the obligations of the clinician once an abnormality is found? Should only information be provided or is there a role in influencing the parents' decision? Two diverse examples are provided to discuss these questions. Mrs A., aged 40 years was noted at the 18-week and then the 20-week scan to have a fetus with a complete atrio-ventricular septal defect. In addition, the fetus had a Danny-Walker cyst. There was thickened nuchal folds and echogenic bowel all suggestive of a chromosomal abnormality. Amniocentesis was refused and the pregnancy continued. Mrs B., aged 34 years was noted at 19 weeks and again at 20 weeks to have a fetus with mild thickening of the walls of both the right and left ventricles. The flow patterns appeared normal. Despite a probable good outlook, the parents asked for a repeat scan at 22 weeks to allow them to consider possible termination. Despite a probable chromosomal abnormality, definite major cardiac and neurological abnormalities, Mrs A. refused karotyping and planned to proceed with the pregnancy. Mrs B., despite a probable good outcome for the fetus asserted pressure for us to prognosticate by 22 weeks. While non-directive counselling is the accepted norm, is that appropriate for all situations? Should one strongly influence Mrs A. to have an amniocentesis to confirm a probable Trisomy thereby allowing her to make a more informed decision? How reassuring can the clinician be to Mrs B. and if termination is sought should one counsel against that? Arguments for these positions are described, highlighting the difficulties faced by clinicians as they counsel parents often with incomplete information and in a setting of acute emotional distress.
Menahem
Samuel
S
Paediatric Cardiology and Fetal Diagnostic Unit, Monash Medical Centre, Melbourne, Australia. samuel.menahem@southernhealth.org.au
Gillam
Lynn
L
D000028:Abortion, Induced; D000328:Adult; D003616:Dandy-Walker Syndrome / Q000000981:diagnostic imaging; D037001:Directive Counseling; D004452:Echocardiography; D005260:Female; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging*; D006343:Heart Septal Defects / Q000000981:diagnostic imaging; D006801:Humans; D011247:Pregnancy; D011379:Prognosis; D016216:Ultrasonography, Prenatal