Clinical Characteristics and Prognosis of Fetal Left Ventricular Noncompaction in Japan

Abstract

We conducted nationwide retrospective surveys of fetuses with cardiomyopathies (CMs) in Japan January 2010 to December 2016, by which we aimed to elucidate the clinical features, diagnosis, and prognosis of fetal LVNC. Methods SubjectsWe conducted a multicenter, retrospective, observational study by inviting 131 hospitals with a fetal or pediatric cardiology department in Japan to participate in a survey of fetal patients with CMs from. After agreeing to participate, we sent a detailed questionnaire and DVD to 20 hospitals to obtain fetal and postnatal clinical and echocardiographic data. The questionnaire elicited maternal, fetal, and postnatal information, such as maternal and L eft ventricular noncompaction (LVNC) is morphologically characterized by a severely thickened, twolayered myocardium and numerous prominent trabeculations and deep intertrabecular recesses that communicate with the LV cavity. 1 The clinical features of LVNC are highly variable: some patients experience no symptoms, whereas others might experience progressive deterioration in cardiac function that results in congestive heart failure, thromboembolism, arrhythmias, and sudden cardiac death. 1-4 Therefore, early diagnosis and appropriate management are crucial.The ability to detect LVNC in the fetus has been rarely described in this population. Although distinct criteria have been established for diagnosing LVNC after birth, those for fetal LVNC diagnosis remain unidentified. 5 A previous study reported that continual morbidity and mortality rates occur in fetal cases of LVNC, even if treated with appropriate care perinatally and during childhood. 6,7 Currently, there are no published data available on the long-term outcomes of fetuses diagnosed with LVNC.

Left Ventricular Noncompaction Develops Even in Late Fetal Life ― The Need for Fetus-Specific Diagnostic Criteria ―

“…Ozawa et al estimate that the incidence of LVNC is 1.49 per 100,000 babies. 9 These data are compatible with data from a previous report 11 that showed that LVNC occurred in 0.81 per 100,000 infants/year. As reported, the prognosis in infants with LVNC is poor because of heart failure and/ or concomitant congenital heart disease.…”

“…Ozawa et al propose that an N/C ratio ≥1.6 at the LV apex on fetal echocardiography is a possible predictor of LVNC after birth. 9 However, their study was retrospective, and…”

Left ventricular noncompaction: a disorder with genotypic and phenotypic heterogeneity—a narrative review

“…Indeed, we reported that sarcomere variants are most commonly identified in fetus-onset patients, and fetus-onset patients with LVNC are more likely to develop HF (90). Moreover, we found a time-dependent increase in the ratio of noncompacted to compressible layers (N/C) of the LV wall in patients with fetal-onset LVNC, with the N/C ratio being greater than 2 before and after birth (91). This change is in contrast to patients with DCM and HCM, suggesting that the formation of the trabeculated layer proceeds late in gestation.…”

“…The prognosis of newborns with mitochondrial disease or metabolic complications is worse, with a higher rate of heart transplantation compared to DCM in children (17). Additionally, fetal-onset cases have a high rate of HF and mortality (5,90,91). In contrast, young and adult-onset cases that are asymptomatic and detected by medical examination or incidentally often have isolated LVNC, are asymptomatic for a long time, and have a good prognosis (17).…”

A case of fetal isolated ventricular noncompaction with TNNT2 gene mutation and literature review

“…15 Additionally, the myocardial manifestations of this fetus were not consistent with hypertrophic cardiomyopathy (HCM, Z-scores of septal and posterior ventricular wall thicknesses greater than 2) or dilated cardiomyopathy (DCM, ventricular dilatation with a cardiothoracic ratio greater than 0.35 complicated with left ventricular dysfunction and left ventricular shortening rate less than 28%). 16 Therefore, the diagnosis of FVNC in this fetus was suggested. Besides, the fetus also showed findings of tricuspid regurgitation and pericardial effusion on ultrasound in late pregnancy with a CVPS of 7/10, indicating a poor prognosis.…”