Abnormal Microscopic Findings in the Placenta Correlate With the Severity of Fetal Heart Failure.

BACKGROUND: This study investigated the association between placental pathology and fetal heart failure.Methods and Results: Singletons with a congenital heart defect (CHD) and/or arrhythmia (n=168) and gestational age-matched controls (n=52) were included in the study. The associations between macro- and microscopic abnormal findings of the placenta and the severity of fetal heart failure were evaluated using the cardiovascular profile (CVP) score. Nine features were microscopically identified and assessed in sections of the placenta: premature villi, edematous villi, fibrotic villi, chorioamnionitis, chorangiosis, fibrin deposition, subchorionic hematoma, infarcted villi, and nucleated red blood cells in villous vessels. Among singletons with CHD and/or arrhythmia, the final CVP score was ≥8 in 140 cases, 6 or 7 in 15 cases, and ≤5 in 13 cases. Microscopic analysis showed that the frequency and severity of premature and edematous villi and increased nucleated red blood cells in villous vessels were greater in cases of fetal heart failure. These microscopic findings were more common and severe in cases with a final CVP score ≤5 than in gestational age-matched controls. The prevalence of abnormal macroscopic findings of the placenta and umbilical cord was similar regardless of the severity of fetal heart failure. CONCLUSIONS: Premature and edematous villi and increased nucleated red blood cells in villous vessels were correlated with the severity of fetal heart failure in cases of CHD and/or arrhythmia.

Utility of perinatal natriuretic peptide for predicting neonatal heart failure.

BACKGROUND: We evaluated the significance of perinatal plasma natriuretic peptide (NP) levels in neonates with congenital heart defects (CHDs) or arrhythmias and determined whether measurement of perinatal plasma NP levels and echocardiographic assessment in utero could predict heart failure after birth. METHODS: The study was conducted between 2012 and 2016 to evaluate the correlation of perinatal atrial NP (ANP) and brain NP (BNP) levels at birth with the modified Ross score after birth and the cardiovascular profile (CVP) score before birth. RESULTS: A total of 122 singletons with CHDs or arrhythmias and 27 controls were analyzed. Neonatal blood sampling was performed at a median of 0.7 h (range, 0.1-1.5) after birth. The neonatal plasma ANP and BNP levels shortly after birth were significantly higher than those in the umbilical artery (UA) plasma. The ANP and BNP levels in UA and neonatal blood were correlated with the modified Ross score. The neonatal plasma ANP and BNP levels and the modified Ross scores were inversely correlated with the CVP score in neonates with CHDs or arrhythmias. The area under the receiver operating characteristic curve of UA ANP levels for predicting neonatal heart failure was highest among those for the CVP score, perinatal plasma ANP and BNP levels, and their combinations. CONCLUSIONS: The plasma ANP and BNP levels increased markedly shortly after birth. Assessment of the UA plasma ANP level at birth and the CVP score in utero may be utilized to predict neonatal heart failure.

Effective Primary Prevention of Atopic Dermatitis in High-Risk Neonates via Moisturizer Application: Protocol for a Randomized, Blinded, Parallel, Three-Group, Phase II Trial (PAF Study).

Background: Atopic dermatitis (AD) is a chronic and inflammatory skin disease that causes health-related burdens associated with pruritus and poor quality of life. Our previous study demonstrated that moisturizer (2e) application has a primary preventive effect on AD. However, this effect was not observed in recent randomized control trials. Thus, the ideal moisturizer type and application frequency for preventing AD development in infants remains unclear. We hypothesize that twice daily application of moisturizer is more effective than once daily application. We predict that applying sufficient amounts of high-quality moisturizer may be effective for preventing AD development in neonates and infants. Here, we describe a protocol for comparing the efficacy of twice daily and once daily application of Fam's Baby™ moisturizer and once daily application of 2e moisturizer for preventing AD in neonates. Methods: This study is a single-center, three-parallel group, assessor-blind, superiority, individually randomized, controlled, phase II trial. Sixty newborns with at least one parent or sibling who has had AD is randomly assigned to application of Fam's Baby twice daily, Fam's Baby once daily, or 2e once daily in a 1:1:1 ratio until 32 weeks old. The primary outcome is the time to the first onset of AD during administration of the moisturizer. Discussion: This is the first phase II randomized, controlled trial in Japan to estimate how effective the twice daily or once daily application of Fam's Baby moisturizer is in preventing AD compared to the once daily application of 2e moisturizer. In this study, we will use 2e once daily as a control to confirm the efficacy for primary prevention of AD as found in our previous trial. Based on the results of this study, we hope to conduct a phase III study to determine the optimal method for preventing AD via moisturizer application. Evaluation of application of moisturizers for preventing AD in this study is expected to contribute to a reduction in the prevalence of AD and a reduction in health care costs. Trial registration: Japan Registry of Clinical Trials (jRCT); ID: jRCTs031200070.

Public attitudes in the clinical application of genome editing on human embryos in Japan: a cross-sectional survey across multiple stakeholders.

Recent advances in genome editing technology are accompanied by increasing public expectations on its potential clinical application, but there are still scientific, ethical, and social considerations that require resolution. In Japan, discussions pertaining to the clinical use of genome editing in human embryos are underway. However, understanding of the public's sentiment and attitude towards this technology is limited which is important to help guide the debate for prioritizing policies and regulatory necessities. Thus, we conducted a cross-sectional study and administered an online questionnaire across three stakeholder groups: the general public, patients and their families, and health care providers. We received responses from a total of 3,511 individuals, and the attitudes were summarized and compared among the stakeholders. Based on the distribution of responses, health care providers tended to be cautious and reluctant about the clinical use of genome editing, while patients and families appeared supportive and positive. The majority of the participants were against the use of genome editing for enhancement purposes. Participants expressed the view that clinical use may be acceptable when genome editing is the fundamental treatment, the risks are negligible, and the safety of the technology is demonstrated in human embryos. Our findings suggest differences in attitudes toward the clinical use of genome editing across stakeholder groups. Taking into account the diversity of the public's awareness and incorporating the opinion of the population is important. Further information dissemination and educational efforts are needed to support the formation of the public's opinion.

Significance of Atrial and Brain Natriuretic Peptide Measurements in Fetuses With Heart Failure.

Fetal heart failure is mainly caused by congenital heart defect and arrhythmia. It is difficult to appropriately diagnose the severity of fetal heart failure simply by ultrasonography because the development of a fetal heart in fetoplacental circulation and how well the fetal myocardium can adapt to postnatal cardiopulmonary circulation are challenging to assess. In adult cardiology, natriuretic peptides (NPs) are the most useful biomarker of heart failure; however, studies investigating NP levels in the fetuses and amniotic fluid are quite limited. Furthermore, little is known about their production and metabolism. This review summarized the most relevant findings on NP levels in the umbilical cord blood and amniotic fluid. The findings can then extend their use as a diagnostic biomarker of heart failure in fetuses with congenital heart defect and/or arrhythmia.

Pediatric Medical Devices　- Survey of Pediatric Cardiologists and Cardiovascular Surgeons in Japan.

Background: In Japan, the choice of pediatric medical devices is limited because of 2 "device lag" problems: Japan lags behind the USA and Europe in device development, and development of pediatric devices lags behind that of adult devices. We aimed to identify the problems with and impediments to pediatric medical device development as recognized by pediatric physicians in Japan. Methods and Results: A voluntary survey of pediatric medical devices for all council members of the Japanese Society of Pediatric Cardiology and Cardiac Surgery was conducted in 2019. The response rate was 47.1% (154/327). The respondents were 115 pediatric cardiologists (74.7%) and 39 cardiovascular surgeons (25.3%). Approximately 90% believed that difficulties in development existed. Approximately 70% were dissatisfied with the pediatric medical devices currently available in Japan, which was a result of the unavailability of medical devices approved overseas, few types and sizes, and off-label use. Factors that hindered the development of pediatric medical devices included anatomical issues specific to children with congenital heart disease, as well as system issues such as lack of corporate profitability, development cost, and amount of time for development. Conclusions: Pediatric cardiologists and cardiovascular surgeons regard "device lag" and "off-label use" in Japan as important hindrances to the delivery of better medical care for pediatric patients with congenital heart disease.

Plasma natriuretic peptide levels reflect the status of the heart failure in fetuses with arrhythmia.

OBJECTIVES: To evaluate the significance of natriuretic peptide (NP) levels in fetal arrhythmia. STUDY DESIGN: Cardiovascular profile (CVP) scores and umbilical vein (UV) NP levels at birth were compared by different fetal arrhythmia statuses. RESULTS: Fetal tachyarrhythmia (n = 22), bradyarrhythmia (n = 12), extrasystole (n = 12) and controls (n = 127) were enrolled in this study. Fetal antiarrhythmic therapy was performed in fetuses with tachyarrhythmia (n = 18) and bradyarrhythmia (n = 5). Fetal arrhythmias were divided into three groups: group A (arrhythmia controlled at birth, n = 17), Group B (arrhythmia uncontrolled at birth, n = 9) and Group C (fetal therapy not indicated, n = 20). Group B had significantly lower CVP scores and higher NP levels than the other two groups and controls (p < .01). Groups A and C had significantly lower CVP scores than controls, but NP levels in Groups A and C showed no differences compared with controls. CONCLUSIONS: UV NP concentrations reflect the severity of fetal arrhythmia and responses to fetal therapy.

Maternal administration of tadalafil improves fetal ventricular systolic function in a Hey2 knockout mouse model of fetal heart failure.

BACKGROUND: There is no established transplacental treatment for heart failure (HF) in utero, and no animal models or experimental systems of fetal HF have been established. This study aimed to investigate the effect of maternal tadalafil administration on fetal cardiovascular function and uteroplacental circulation in a murine model of fetal HF. METHODS AND RESULTS: We first used an ultra-high-frequency ultrasound imaging system in utero and demonstrated that Hey2-/- embryos had worsening right ventricular hypoplasia and marked left ventricular (LV) dilatation as gestation progressed. In both ventricles, fractional shortening (FS) and the E/A ratio were significantly lower in Hey2-/- embryos than in wild-type embryos, indicating that the embryos can be used as a murine model of fetal HF. Subsequently, we evaluated the effect of tadalafil treatment (0.04 or 0.08 mg/ml; T0.04 or T0.08 groups, respectively) on fetoplacental circulation in Hey2-/- embryos. LV FS was significantly higher in the T0.04 group than in control (P < 0.01), whereas LV dilation, mitral E/A ratio, and umbilical artery resistance index were not significantly different among all groups. The thinness of the LV compacted layer did not differ between the T0.04 and vehicle-treated Hey2-/- embryos. CONCLUSIONS: A phenotype comprising marked dilatation and reduced FS of the left ventricles was identified in Hey2-/- embryos, suggesting these embryos as a murine model of fetal HF. In addition, maternal administration of tadalafil improved LV systolic function without altering LV morphological abnormalities in Hey2-/- embryos. Our findings suggest that tadalafil is a potential agent to treat impaired fetal ventricular systolic function.

Metabolism of atrial and brain natriuretic peptides in the fetoplacental circulation of fetuses with congenital heart diseases.

INTRODUCTION: Natriuretic peptides (NPs) play a pivotal role in maintaining fetal circulation; however, little is known about their metabolism. The aim of the present study was to elucidate the metabolism of plasma NPs in the fetoplacental circulation. METHODS: Plasma NP concentrations in maternal vein and umbilical artery (UA) and vein (UV) samples from fetuses with congenital heart defect (n = 86) or arrhythmia (n = 31) and controls (n = 127) were analyzed. RESULTS: Levels of plasma atrial NP (ANP) and brain NP (BNP) showed good correlation between UV versus UA samples (p < 0.01). In all three fetus groups, the regression coefficients between UV and UA plasma ANP levels were close to 0.5, while those between UV and UA plasma BNP levels were close to 1. The molecular forms of immunoreactive ANP in UA plasma showed a single peak corresponding to mature ANP, while those of immunoreactive BNP in UA plasma showed two major peaks and several minor peaks corresponding to mature BNP-32 and its partially digested peptides, as well as glycosylated and non-glycosylated BNP precursors (proBNP). No correlation was found between fetuses and mothers in terms of either plasma ANP or BNP levels. CONCLUSIONS: The mother and fetus independently secrete and metabolize both ANP and BNP. Fetal plasma ANP consists exclusively of the mature form, and the placenta and umbilical vessels are possible major sites of ANP metabolism. In contrast, fetal plasma BNP consists predominantly of the precursor forms, which may contribute to protecting BNP from metabolism in the fetoplacental circulation.

Antenatal Therapy for Fetal Supraventricular Tachyarrhythmias: Multicenter Trial.

BACKGROUND: Standardized treatment of fetal tachyarrhythmia has not been established. OBJECTIVES: This study sought to evaluate the safety and efficacy of protocol-defined transplacental treatment for fetal supraventricular tachycardia (SVT) and atrial flutter (AFL). METHODS: In this multicenter, single-arm trial, protocol-defined transplacental treatment using digoxin, sotalol, and flecainide was performed for singleton pregnancies from 22 to <37 weeks of gestation with sustained fetal SVT or AFL ≥180 beats/min. The primary endpoint was resolution of fetal tachyarrhythmia. Secondary endpoints were fetal death, pre-term birth, and neonatal arrhythmia. Adverse events (AEs) were also assessed. RESULTS: A total of 50 patients were enrolled at 15 institutions in Japan from 2010 to 2017; short ventriculoatrial (VA) SVT (n = 17), long VA SVT (n = 4), and AFL (n = 29). One patient with AFL was excluded because of withdrawal of consent. Fetal tachyarrhythmia resolved in 89.8% (44 of 49) of cases overall and in 75.0% (3 of 4) of cases of fetal hydrops. Pre-term births occurred in 20.4% (10 of 49) of patients. Maternal AEs were observed in 78.0% (39 of 50) of patients. Serious AEs occurred in 1 mother and 4 fetuses, thus resulting in discontinuation of protocol treatment in 4 patients. Two fetal deaths occurred, mainly caused by heart failure. Neonatal tachyarrhythmia was observed in 31.9% (15 of 47) of neonates within 2 weeks after birth. CONCLUSIONS: Protocol-defined transplacental treatment for fetal SVT and AFL was effective and tolerable in 90% of patients. However, it should be kept in mind that serious AEs may take place in fetuses and that tachyarrhythmias may recur within the first 2 weeks after birth.

A less-intensive anticoagulation protocol of therapeutic unfractionated heparin administration for pregnant patients.

Heparin anticoagulant therapy for thromboembolic disorders during pregnancy is problematic due to unexpected adverse bleeding. To avoid bleeding, we have used a less-intensive anticoagulation protocol of unfractionated heparin (UFH). The protocol had a therapeutic activated partial thromboplastin time (APTT) ratio of 1.5-2.0 with the control value, a UFH dose of ≤ 30,000 U/day, and an antithrombin (AT) activity target of ≥ 70%. In the present study, we evaluated this protocol using an anti-Xa assay. We collected UFH-treated plasma samples from ten consecutive pregnant Japanese patients with current or previous thromboembolic disorders. Seven patients remained in the therapeutic APTT ratio range (heparin-sensitive [HS] group). The other three patients had difficulty remaining within the therapeutic range (heparin-resistant [HR] group). In the HR group, two had AT deficiency and one had congenital absence of the inferior vena cava. Of the HS and HR samples, 73% and 31%, respectively, were within the therapeutic anti-Xa activity range 0.3-0.7 U/mL, indicating difficulty for the HR group to remain within the therapeutic range. Neither major bleeding nor symptomatic thromboembolic episodes occurred in either group. These findings suggest that the less-intensive anticoagulation protocol is permissive and may be beneficial in the HS group.

Predicting postpartum cardiac events in pregnant women with complete atrioventricular block.

BACKGROUND: Women with complete atrioventricular block (CAVB) can tolerate hemodynamic changes during pregnancy; however, the incidence of cardiac events in women with CAVB may increase after delivery. The aim of this study was to investigate predictive factors for postpartum cardiac events in pregnant women with CAVB. METHODS AND RESULTS: Pregnant women with CAVB who received perinatal management at a tertiary cardiac center from 1981 to 2015 were retrospectively reviewed. Univariate and multivariate logistic analyses of postpartum cardiac events were performed. Postpartum cardiac event was defined as cardiopulmonary arrest, cardiac failure, or the need for permanent pacemaker implantation (p-PMI) within 3 months after delivery. A total of 63 pregnancies in 36 women with CAVB were included in this study; 25 had undergone p-PMI before pregnancy. Regardless of p-PMI status, women with CAVB had no further increases in heart rate during the second and third trimesters. No heart failure was found during pregnancy and delivery. Postpartum cardiac events occurred in 9 pregnancies (14.3%) in 8 women with CAVB; 3 had cardiac failure and p-PMI, 3 had cardiac failure, 2 required p-PMI, and 1 had cardiopulmonary arrest. Multivariate analysis showed that perinatal ventricular pause (odds ratio 11.60, 95% confidence interval 1.90-82.18, p<0.01) and family history of CAVB (odds ratio 10.59, 95% confidence interval 1.36-90.56, p=0.03) were associated with postpartum cardiac events. CONCLUSIONS: All cardiac events occurred during the postpartum period among women with CAVB, and ventricular pause during the perinatal period and a family history of CAVB were predictors of postpartum cardiac events. Close follow-up should be considered during the postpartum period for women with high-risk CAVB.

Cardiovascular profile and biophysical profile scores predict short-term prognosis in infants with congenital heart defect.

AIM: To predict the prognosis of infants with congenital heart disease, accurate prenatal diagnosis of structural abnormality and heart failure are both necessary. The aim of this study was to investigate whether cardiovascular profile (CVP) and biophysical profile (BP) scores are useful for predicting prognosis in infants with congenital heart defect (CHD). METHODS: A retrospective review of singletons prenatally diagnosed with CHD at a tertiary pediatric cardiac center between 2011 and 2015 was undertaken. RESULTS: A total of 202 patients with CHD were analyzed. Perinatal and infant deaths occurred in 16 (7.9%) and 10 cases (5.0%), respectively. Infants with the last CVP score ≤ 5 had 18.7-fold higher perinatal mortality than those with a last CVP score > 5 (P < 0.01). Infants with a last BP score ≤ 6 had 18.7-fold higher perinatal mortality than those with a last BP score > 6 (P < 0.01). Infants with a CVP score decrease in utero had 4.5-fold higher infant mortality than those with an increase or no change (P < 0.01). Multivariate analysis showed that single-ventricle physiology, pre-term birth at <37 weeks of gestation, last CVP score ≤ 5, and last BP score ≤ 6 were independent predictors of perinatal mortality. Single-ventricle physiology and a CVP score decrease were independent predictors of infant mortality. CONCLUSION: CVP and BP scores are useful for predicting perinatal prognosis in infants with CHD. A CVP score decrease in utero is associated with infant mortality, suggesting that serial CVP score assessment may be useful for management planning.

Effects of low-dose combined oral contraceptives and protein S K196E mutation on anticoagulation factors: a prospective observational study.

The association between low-dose combined oral contraceptives (COCs) and anticoagulation factors in Japanese women has been rarely studied. A total of 394 Japanese women with a new beginning cycle of COC use were enrolled, of whom 335 women visited the clinic within 4 weeks after starting the first cycle of COC. Visits occurred in the active phase (272 women) and the placebo phase (63 women). Free protein S (PS) antigen and activity levels and antithrombin activity levels decreased significantly in both the active and placebo phase groups. Protein C (PC) activity levels increased significantly in both groups. Larger reductions in free PS antigen and activity levels occurred with COC comprising either 30 µg ethinylestradiol/desogestrel or 20 µg ethinylestradiol/drospirenone than that comprising 35 µg ethinylestradiol/norethisterone. In four women with the Japanese-specific PS K196E mutation, mean PS activity was 65% before COC use and 57% during COC use, indicating further decrease with COC use. In conclusion, decreased antigen and activity levels of PS and antithrombin and increased activity levels of PC were observed even during the first cycle of low-dose COC use. The effects on PS and PC activities were also observed in the hormone-free interval.

Maternal and fetal outcomes in pregnancy complicated with Eisenmenger syndrome.

OBJECTIVE: The goal of the study was to clarify the risk factors for pregnancy complicated with Eisenmenger syndrome (ES). MATERIALS AND METHODS: A retrospective study was performed in 15 patients with ES who were managed throughout pregnancy at one institution from 1982 to 2013. Cases associated with congenital heart diseases other than atrial septal defect (ASD), ventricular septal defect (VSD), and patent ductus arteriosus (PDA) were excluded. RESULTS: The congenital heart diseases in ES included ASD (n = 3), VSD (n = 9), and PDA (n = 3). Ten women chose termination and 5 continued with their pregnancies. In the 5 continuation cases (PDA 1, VSD 4), worsening of cyanosis, exertional fatigue and dyspnea appeared between 25 and 30 weeks gestation and cesarean section was performed at 30 (28-33) weeks. LVEF, PaO2, and SpO2 decreased and heart rate increased significantly from before pregnancy to 25-30 weeks gestation. From before to during the pregnancy, there were no significant changes in mean PABP or pulmonary vascular resistance (PVR) in four cases with data (582-592, 885 to 868, 1280 to 1291, 1476-1522 dyn × s/cm2). PVR at conception had a negative relationship with delivery weeks. NYHA classes before, during and 1 year after pregnancy were II, III and II. In one recent case, epoprostenol and tadalafil were administered during pregnancy. CONCLUSIONS: Pregnancy with ES has a high risk due to hypooxygenation, cyanosis, and cardiac failure, which can appear as common complications as early as the 2nd trimester. Early interventions with meticulous care are required for these complications during pregnancy and delivery.

Tadalafil treatment in mice for preeclampsia with fetal growth restriction has neuro-benefic effects in offspring through modulating prenatal hypoxic conditions.

We have demonstrated that tadalafil facilitates fetal growth in mice with L-NG-nitroarginine methyl ester (L-NAME)-induced preeclampsia (PE) with fetal growth restriction (FGR). Tadalafil is a selective phosphodiesterase 5 inhibitor that dilates the maternal blood sinuses in the placenta, thereby facilitating the growth of the fetus. The purpose of this study was to investigate the effects of tadalafil treatment for PE and FGR on the developing brain in FGR offspring using an L-NAME-induced mouse model of PE with FGR. A control group of dams received carboxymethylcellulose (CMC). L-NAME-treated groups received L-NAME dissolved in CMC from 11 days post coitum (d.p.c.). The L-NAME-treated dams were divided into two subgroups 14 d.p.c. One subgroup continued to receive L-NAME. The other subgroup received L-NAME with tadalafil suspended in CMC. Tadalafil treatment for PE with FGR reduced the expression of hypoxia-inducible factor-2α in the placenta and in the brain of the FGR fetus. Moreover, tadalafil treatment in utero shows improved synaptogenesis and myelination in FGR offspring on postnatal day 15 (P15) and P30. These results suggest that tadalafil treatment for PE with FGR not only facilitates fetal growth, but also has neuroprotective effects on the developing brain of FGR offspring through modulating prenatal hypoxic conditions.

Prediction of postnatal arrhythmia in fetuses with cardiac rhabdomyoma.

OBJECTIVES: Fetal cardiac rhabdomyomas are rare but well-known to be associated with arrhythmia or conduction abnormalities. However, since in utero electrophysiological information is quite limited, it remains unclear which type of rhabdomyoma will develop arrhythmia after birth. The aim of this study is to identify factors that predict postnatal arrhythmia requiring therapy in fetuses with cardiac rhabdomyoma. STUDY DESIGN: A retrospective review of infants prenatally diagnosed with cardiac rhabdomyoma was performed at our tertiary pediatric cardiac center between 1990 and 2016. Fetal arrhythmia was diagnosed using fetal echocardiography and magnetocardiography. We compared the characteristics of cases with and without antiarrhythmic therapy after birth. Cases without antiarrhythmic therapy after birth consisted of those who had postnatal arrhythmia but did not require antiarrhythmic therapy and those who had no postnatal arrhythmia. RESULTS: A total of 20 fetuses with cardiac rhabdomyoma were included in this study. Ten cases (50%) were confirmed as having tuberous sclerosis after birth. The mean gestational week at diagnosis and delivery were 32.1 ± 2.7 and 37.6 ± 2.8 weeks, respectively. Mean cardiac tumor size in utero was 21 ± 11 mm (range, 7-54 mm) in diameter. Fetal arrhythmia was found in six cases; three resolved in utero with transplacental antiarrhythmic therapy. Postnatal arrhythmia or conduction abnormalities were found in 12 cases; 7 required antiarrhythmic therapy. Cases with antiarrhythmic therapy after birth had larger cardiac tumor in utero than those without therapy (29.6 ± 12.8 mm versus 16.3 ± 5.8 mm, p < .01). Cardiac tumor size >30 mm in diameter predicted postnatal arrhythmia requiring therapy with sensitivity of 57.1% and specificity of 100%. Location and number of cardiac tumor and presence of arrhythmia or conduction abnormalities in utero were similar between the two groups. CONCLUSIONS: Cardiac rhabdomyomas >30 mm in diameter are associated with postnatal arrhythmia requiring therapy regardless of number and location.