Ozawa SW, Takarada S, Okabe M, Miyao N, Nakaoka H, Ibuki K, Ichida F, Hirono K; Fetal CM Study Collaborators. Circ J. 2021 Dec 24;86(1):98-105. doi: 10.1253/circj.CJ-20-1148. Epub 2021 Aug 3. PMID: 34349074
Take Home Points:
- Left ventricular non-compaction (LVNC) can be diagnosed prenatally.
- The postnatal diagnostic criteria of N/C ratio of >2 does not seem to apply to fetal life. A non-compacted to compacted (N/C) ration> 1.6 is predictive of postnatal LVNC.
- Fetal LVNC is commonly associated with development of CHD
- Fetal DCM and LVNC is associated with high morbidity and mortality.
- Prospective multicenter studies are needed to further delineate the course of fetal cardiomyopathy, and to establish diagnostic criteria for LVNC by gestational age.
Commentary from Dr. Anna Tsirka (Connecticut, USA), Section editor of Pediatric & Fetal Cardiology Journal Watch.
Fetal diagnosis of left ventricular non compaction (LVNC) has rarely been described, diagnostic criteria have not been established and there are no published data on long term outcomes of fetal LVNC. This represents a retrospective nationwide study of fetuses with cardiomyopathy (CM) in Japan that includes fetuses diagnosed between January 2010 and December 2016.
All centers who provide fetal and cardiology services in Japan were invited to participate. Of 131 hospitals invited, 20 agreed to participate. Participating centers filled out questionnaires with pre and postnatal clinical and echocardiographic data. DVDs with echocardiograms were analyzed by two independent reviewers and the analysis was repeated again 8 weeks later to evaluate intra- and inter-observer variation.
Fetuses with maternal diabetes and SSA AV block were excluded. LVNC diagnosis was bases on non-compacted to compacted (N/C) ratio of >2 in >1 ventricular wall segment. Cardiac dysfunction for a fetus was defined as LVFS<28% and cardiac enlargement was defined as cardiothoracic area ratio (CTAR)>35%. Cardiovascular profile score (CVPS) was calculated. Postnatal follow up ranged from 0 to 64 months.
Data were collected in 47 fetuses, and 9 were excluded as being secondary cardiomyopathies. Of 38 fetuses with CM in fetal life, 16 had LVNC, 15 had DCM and 7 had HCM. Most fetuses were diagnosed by routine screening, while 26% had a fetal echocardiogram because of family history of CM. Interestingly, 50% of fetuses with LVNC had positive family history of CM, while only 13%of DCM fetuses and none of HCM fetuses had family history of CM. Hydrops was most common in DCM (26%) vs 12.5 and 14.2% in LVNC and HCM respectively.
Echocardiographic parameters prenatally at diagnosis are presented below:
3 fetuses suffered intrauterine death (1 LVNC, 2 DCM). Half of the infants were delivered by c section. Concordance between prenatal and postnatal diagnosis was 60%. Risk Factors for postnatal diagnosis of LVNC were N/C ratio at the apex at first fetal echocardiogram of >1.6 (OR 69.6) and family history of CM (OR 10). Extracardiac involvement and findings of genetic syndromes was common in HCM (42.8%), but not in LVNC or DCM. Postnatal arrhythmia was most common in LVNC (26.6%).
Of the patients with LVNC, 9 developed some form of CHD.
Echocardiographic parameters at first visit are described below:
Mitral regurgitation was most common in infants with DCM.
In patients with LVNC, the N/C ratio increased with each evaluation from fetal to postnatal life, and was most prominent at the apex and lateral wall (figure below):
Overall 24 neonates received medical treatment, with 20 of those requiring inotropic support. 18 infants required ventilator support.
During the period of the study, 16 patients died (3 intrauterine) or underwent heart transplant (73% of the DCM patients, 25% of the LVNC and 14% of the HCM patients.