Prevalence of Left Ventricular Noncompaction in Newborns

Abstract

Background: Left ventricular noncompaction (LVNC) is characterized by excessive trabeculations of the LV and may be associated with reduced systolic function or severe adverse outcomes. Several aspects remain to be elucidated; there is controversy to whether LVNC cardiomyopathy is a distinct cardiomyopathy caused by failure of the spongy fetal myocardium to condense during fetal development or acquired later in life as a morphological trait associated with other types of cardiomyopathy; the prevalence in unselected populations is unknown and the distinction between normal variation and pathology remains to be defined. In this study, we aimed to determine the prevalence of LVNC and the association to LV systolic function in a large, population-based cohort of neonates. In addition, we assessed the normal ratio of noncompact to compact (NC:C) myocardium in 150 healthy neonates. Methods: Echocardiographic data were prospectively collected in the population study Copenhagen Baby Heart Study. The ratio of NC:C was measured in 12 ventricular segments. LVNC was defined as NC:C ≥2 in at least one segment. Neonates with LVNC were matched 1:10 to controls on sex, gestational age, and weight and age at the examination day. Results: In total, 25 590 neonates (52% males, median age 11 [interquartile range, 7–15] days) underwent echocardiography. Among 21 133 with satisfactory visualization of ventricular segments, we identified a prevalence of LVNC of 0.076% (95% CI, 0.047–0.123). LV ejection fraction was lower in neonates with LVNC compared with matched controls (median 49.5 versus 59.0%; P <0.0001). In neonates with otherwise healthy hearts, the median NC:C ratio ranged from 0.0 to 0.7 and the 99th percentiles from 1.0 to 1.9 for each of the 12 segments. Conclusions: The prevalence of LVNC based on neonatal echocardiography was 0.076%. LVNC was associated with lower LV systolic function. The findings in normal newborns support the cutoff NC:C ≥2 as an appropriate diagnostic criterion. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02753348.

Prevalence of Left Ventricular Noncompaction in Newborns by Echocardiography: Is This the Most Accurate Approach?

“…The work presented herein by Børresen et al 1 advances our current views of the extent of LVNC in a normal neonatal population and supports the idea that LVNC is in fact a true disease that occurs in utero and postnatally and thus is appropriately classified as a form of cardiomyopathy, along with dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), restrictive cardiomyopathy, and arrhythmogenic cardiomyopathy. 6 The incidence and prevalence of LVNC has been studied since the 1990s but has remained uncertain because of changing diagnostic criteria and predilection for LV hyper-trabeculation in certain populations 9–13 and absence of symptoms in many patients.…”

“…In a registry of pediatric cardiomyopathy patients, noncompaction was discovered in 5% of patients. 17 Børresen et al 1 report a 0.076% prevalence in a pure neonatal population, a much lower percent than reported by others evaluating older children and adults. It is unclear whether this difference is due to the age of the patients studied compared with prior studies, the stringency of the echocardiographic criteria used in the CBHS, the race and ethnicity of the population studied, or the lack of other features of the study population including other cardiomyopathy features such as arrhythmias, hypertrophy, dilation, or restrictive physiology.…”

“…4,5 LVNC was formally classified as a distinct form of cardiomyopathy by the American Heart Association Scientific Statement on the classification of cardiomyopathies in 2006, 6 while the European Working Group on Myocardial Disease considers LVNC as a trait rather than a specific form of heart muscle disease. 7 In the study reported here by Børresen et al, 1 echocardiographic data were prospectively collected from which the authors assessed the normal ratio of noncompact to compact (NC:C) myocardium in 150 healthy neonates in the CBHS undergoing echocardiography. The apical long-axis views (4-chamber, 5-chamber, and sinus coronarius views), parasternal long axis view, and parasternal short axis view (SAX) at the level of the papillary muscles in end-diastole were analyzed and the ratio of NC:C was measured in 12 ventricular segments in all babies.…”

Excessive Trabeculation of the Left Ventricle

“… 15 To our knowledge, prevalence of excessive trabeculation, at 0.076%, has been assessed in only 1 population-based neonatal echocardiographic study. 16 …”

Emerging Hallmarks of Mitochondrial Biochemistry in Cardiac Trabecular Morphogenesis and Left Ventricular Noncompaction (LVNC)

“…Echo criteria include (1) noncompacted/compacted ratio of the two-layered endocardium of >2, (2) left ventricular deep endomyocardial trabeculations, and (3) deep recesses filled with blood visualized on color Doppler [48,49]. However, the detection of LVNC in its early stage of development are challenging, with only around 0.3% of the patients being referred for an echo [50,51]. Additionally, echo diagnostics are sometimes considered to be a 'too sensitive of a method' as overdiagnosis frequently occurs, particularly in the black patient population.…”