Fetal cardiomyopathy refers to a very rare situation where a cardiomyopathy occurs in utero. It is often a diagnosis of exclusion where, by definition, there is an absence of an underlying congenital cardiac morphological anomaly.
The estimated incidence is variable with the high end of the reported spectrum approaching 1 in 5000 births 6.
It often results from a primary dysfunction in cardiac muscle functioning (i.e. no underlying chamber morphological or valvular anomaly)
There are two main subtypes
- fetal hypertrophic cardiomyopathy: relatively more common 7
- fetal dilated cardiomyopathy: relatively rarer
A fetal cardiomyopathy can have a broad spectrum of syndromic, as well non-syndromic, associations, which include:
- Barth syndrome 1: X-linked disorder which can result in a fetal dilated cardiomyopathy
- congenital infection 4: generally tend to develop a dilated cardiomyopathy
- endocardial fibroelastosis related to maternal anti-Ro/La antibodies 4: generally tend to develop a dilated cardiomyopathy
- fetal high output states:
- Noonan syndrome 4,6: tend to develop a hypertrophic cardiomyopathy
- maternal diabetes: tend to develop a hypertrophic cardiomyopathy
- twin-twin transfusion syndrome: the pump twin may develop a hypertrophic cardiomyopathy
Dedicated fetal echocardiography is often required. Radiographic features will depend on the subtype. Often the fetal heart is enlarged resulting in an increased cardiothoracic circumferential ratio.
Treatment and prognosis
A poor outcome is observed in many affected fetuses. The presence of diastolic dysfunction in a fetal cardiomyopathy is considered to be associated with the highest risk of mortality 4. Treatment options vary depending on the presence of associated conditions (e.g. control of underlying twin-twin transfusion syndrome, etc.).
- progression to hydrops fetalis
- 1. Steward CG, Newbury-ecob RA, Hastings R et-al. Barth syndrome: an X-linked cause of fetal cardiomyopathy and stillbirth. Prenat. Diagn. 2010;30 (10): 970-6. doi:10.1002/pd.2599 - Free text at pubmed - Pubmed citation
- 2. Yinon Y, Yagel S, Hegesh J et-al. Fetal cardiomyopathy--in utero evaluation and clinical significance. Prenat. Diagn. 2007;27 (1): 23-8. doi:10.1002/pd.1612 - Pubmed citation
- 3. Schmidt KG, Birk E, Silverman NH et-al. Echocardiographic evaluation of dilated cardiomyopathy in the human fetus. Am. J. Cardiol. 1989;63 (9): 599-605. Am. J. Cardiol. (link) - Pubmed citation
- 4. Pedra SR, Smallhorn JF, Ryan G et-al. Fetal cardiomyopathies: pathogenic mechanisms, hemodynamic findings, and clinical outcome. Circulation. 2002;106 (5): 585-91. Circulation (link) - Pubmed citation
- 5. Mongiovì M, Fesslova V, Fazio G et-al. Diagnosis and prognosis of fetal cardiomyopathies: a review. Curr. Pharm. Des. 2010;16 (26): 2929-34. Curr. Pharm. Des. (link) - Pubmed citation
- 6. Drose JA. Fetal Echocardiography. W B Saunders Co. (2009) ISBN:1416056696. Read it at Google Books - Find it at Amazon
- 7. Bianchi DW, Crombleholme TM, D'Alton ME. Fetology, diagnosis & management of the fetal patient. McGraw-Hill Professional. (2000) ISBN:0838525709. Read it at Google Books - Find it at Amazon