Prevalence of Bicuspid Aortic Valve and Associated Aortopathy in Newborns in Copenhagen, Denmark

IMPORTANCE: The prevalence and characteristics of bicuspid aortic valve (BAV) are mainly reported from selected cohorts. BAV is associated with aortopathy, but it is unclear if it represents a fetal developmental defect or is secondary to abnormal valve dynamics. OBJECTIVE: To determine the prevalence of BAV and BAV subtypes and to describe the associated aortopathy in a large, population-based cohort of newborns. DESIGN, SETTING, AND PARTICIPANTS: The Copenhagen Baby Heart Study was a cross-sectional, population-based study open to all newborns born in Copenhagen between April 1, 2016, and October 31, 2018. Newborns with BAV were matched 1:2 to newborns with a tricuspid aortic valve (non-BAV group) on sex, singleton/twin pregnancy, gestational age, weight, and age at time of examination. EXPOSURES: Transthoracic echocardiography within 60 days after birth. MAIN OUTCOMES AND MEASURES: Primary outcome was BAV prevalence and types, ie, number of raphes and spatial orientation of raphes or cusps (no raphes), according to the classification system of Sievers and Schmidtke (classified as type 0, 1, or 2, with numbers indicating the number of raphes). Secondary outcome was valve function and BAV-associated aortopathy, defined as aortic diameter z score of 3 or greater or coarctation. RESULTS: In total, 25 556 newborns (51.7% male; mean age, 12 [SD, 8] days) underwent echocardiography. BAV was diagnosed in 196 newborns (prevalence, 0.77% [95% CI, 0.67%-0.88%]), with male-female ratio 2.1:1. BAV was classified as type 0 in 17 newborns (8.7% [95% CI, 5.5%-13.5%]), type 1 in 178 (90.8% [95% CI, 86.0%-94.1%]) (147 [75.0% {95% CI, 68.5%-80.5%}] right-left coronary raphe, 27 [13.8% {95% CI, 9.6%-19.3%}] right coronary–noncoronary raphe, 4 [2.0% {95% CI, 0.8%-5.1%}] left coronary–noncoronary raphe), and type 2 in 1 (0.5% [95% CI, 0.1%-2.8%]). Aortic regurgitation was more prevalent in newborns with BAV (n = 29 [14.7%]) than in those without BAV (1.3%) (absolute % difference, 13.4% [95% CI, 7.8%-18.9%]; P < .001). Newborns with BAV had higher flow velocities across the valve (0.67 [95% CI, 0.65-0.69] m/s vs 0.61 [95% CI, 0.60-0.62] m/s; mean difference, 0.06 m/s [95% CI, 0-0.1]) and larger aortic root and tubular ascending aortic diameters than those without BAV (10.7 [95% CI, 10.7-10.9] mm vs 10.3 [95% CI, 10.2-10.4] mm; mean difference, 0.43 mm [95% CI, 0.2-0.6 mm] and 9.8 [95% CI, 9.6-10.0] mm vs 9.4 [95% CI, 9.3-9.5] mm; mean difference, 0.46 mm [95% CI, 0.30-0.70], respectively) (P < .001 for all). Aortopathy was seen in 65 newborns (33.2%) with BAV (62 with aortic z score ≥3; 3 with coarctation). CONCLUSIONS AND RELEVANCE: Among newborns in Copenhagen, the prevalence of BAV was 0.77%. Aortopathy was common in newborns with BAV, suggesting that it also represents a fetal malformation

Impact of maternal age and body mass index on the structure and function of the heart in newborns: a Copenhagen Baby Heart Study

Abstract Background Maternal obesity and advanced age have been associated with an increased risk of structural congenital heart defects in the offspring. Whether these factors may also cause abnormalities in infant cardiac dimension and function is unknown. This study investigates whether maternal body mass index (BMI) and maternal age are associated with changes in left ventricular (LV) dimensions and function in the newborn. Methods Infants enrolled in the Copenhagen Baby Heart Study (CBHS), who were born at term, and contributed with a transthoracic echocardiography (TTE) within 60 days of birth were included. The exposure variables were prepregnancy maternal BMI (kg/m2) < 18.5; 18.5–24.9 (reference); 25–29.9; 30–34.9 and ≥ 35 and maternal age (years) < 25; 25–29; 30–34 (reference); 35–39 and ≥ 40. Outcomes were LV parameters ascertained by 2D-echocardiography. Associations between each maternal factor and infant LV parameters were analysed with either a linear model adjusted for the child’s weight and length at birth, gestational age, sex, age at TTE, and maternal smoking, or a linear mixed model, further adjusted for random effects of analyst and month of analysis. Analyses investigating impact of maternal BMI were adjusted for maternal age, and vice versa. Results The study cohort included 24,294 infants. Compared with infants in the BMI reference group, infants born to women with a BMI ≥ 25 kg/m2 generally had smaller measures of LV internal diameters in end-diastole, reaching statistical significance for BMI 30–34.9 kg/m2 [-0.11 ± 0.04 mm, p = 0.01]. All groups of infants born to women with a BMI ≥ 25 kg/m2 had significantly smaller LV internal diameters in end-systole: BMI 25–29.9 kg/m2 [-0.04 ± 0.02 mm, p = 0.04], BMI 30–34.9 kg/m2 [-0.12 ± 0.03 mm, p = 0.001] and BMI ≥ 35 kg/m2 [-0.11 ± 0.05 mm, p = 0.03]. Compared with infants in the age reference group, infants born to women ≥ 40 years had significantly smaller LV internal diameters in end-diastole [-0.15 ± 0.04 mm, p = 0.001] and end-systole [-0.09 ± 0.04 mm, p = 0.009]. Conclusions Systematic population-based echocardiography of infants showed that a maternal prepregnancy BMI ≥ 25 kg/m2 and maternal age ≥ 40 years were associated with smaller systolic and diastolic LV diameters. The long-term effects are unknown. Clinical trial registration April 2016, Copenhagen Baby Heart, NCT02753348