Left atrial vortex flow and its relationship with left atrial functions in patients with congenital heart disease.

BACKGROUND: Four-dimensional flow magnetic resonance imaging (MRI) enables blood flow visualization. The absence of left atrial vortex flow (LAVF) has been implicated in the development of thrombus formation and arrhythmias. However, the clinical relevance of this phenomenon in patients with congenital heart disease (CHD) remains unclear. This study aimed to unravel the relationship of LAVF with left atrial functions in patients with CHD. RESULTS: Twenty-five participants who underwent cardiac MRI examinations were included (8 postoperative patients with CHD aged 17-41 years and 17 volunteers aged 21-31 years). All participants were in sinus rhythm. Four-dimensional flow MRI (velocity encoding 100 cm/s) assessed the presence of LAVF, and its relationship with left atrial function determined by transthoracic echocardiography was explored. LAVF was detected in 16 patients. Upon classification of the participants based on the presence or absence of LAVF, 94% of participants in the LAVF group were volunteers, while 78% of those in the without LAVF group were postoperative patients. Participants without LAVF had a significantly lower left atrial ejection fraction (61% vs. 70%, p = 0.019), reservoir (32% vs. 47%, p = 0.006), and conduit (22% vs. 36%, p = 0.002) function than those with LAVF. CONCLUSIONS: LAVF occurred during the late phase of ventricular systole, and left atrial reservoir function may have contributed to its occurrence. Many postoperative patients with CHD experienced a loss of LAVF. LAVF may indicate early left atrial dysfunction resulting from left atrial remodeling.

Unguarded Tricuspid Valve and Pulmonary Atresia With Intact Ventricular Septum Complicated With Right Coronary Artery Fistula and Advanced Atrioventricular Block in a Fetus: A Case Report.

The unguarded tricuspid valve is a rare and severe condition. When found in the fetus, they mostly undergo abortion or intrauterine death. The details of the fetal course in such cases are poorly understood. Here, we report a case of an unguarded tricuspid valve detected at 20 weeks of gestation who developed a complete atrioventricular block and survived in utero. The fetus also had pulmonary atresia with intact ventricular septum, Uhl's disease, hypoplastic right ventricle, noncompacted left ventricle, valvular aortic stenosis, and right coronary artery fistula to the right ventricle. Despite this serious condition, the fetal hydrops did not develop. The baby was born at 33 weeks of gestation but died on day two. Our experience suggests that some babies may survive the fetal period even with the severe type of an unguarded tricuspid valve. Hence, efficient fetal and neonatal treatment strategies for fetal unguarded tricuspid valves are crucial.

Postoperative evaluation of left atrial stiffness in patients with congenital heart diseases.

Left atrial (LA) stiffness is one of the most important factors involved in LA remodeling. LA stiffness has rarely been studied postoperatively in patients with congenital heart diseases (CHDs). This study aimed to evaluate LA stiffness in CHD patients postoperatively. Seventy-five patients (CHDs, 67; controls, 8; age range, 10-41 years) who underwent cardiac catheterization at our institution were included in this study. From the pulmonary artery wedge pressure waveform obtained during cardiac catheterization, the pressure range between the v wave and x trough was determined, and this value was divided by the LA reservoir strain obtained by echocardiography to calculate LA stiffness, as previously reported. LA stiffness was significantly higher in postoperative CHD patients than in controls (0.28 ± 0.17 vs. 0.13 ± 0.03, p = 0.001). Nineteen of 52 (37%) patients in their teens, 8 of 11 (73%) patients in their 20 s, and 1 of 4 (25%) patients aged > 30 years had elevated LA stiffness values. In particular, all patients with an LA reservoir strain < 20% had elevated LA stiffness. In postoperative CHD patients, LA stiffness was frequently elevated from a young age. CHD patients with elevated LA stiffness should be cautious of possible LA dysfunction in the future.

Liver Fibrosis Markers Represent Central Venous Pressure in Post-pubertal Patients With Congenital Heart Disease.

Background Central venous pressure (CVP) is one of the most important hemodynamic parameters in patients with congenital heart disease (CHD). In adults, it is well-known that liver fibrosis markers reflect CVP, but this is not well-understood in children. We investigated the liver fibrosis markers in pediatric CHD patients and their ability to predict CVP. Methods We studied 160 patients who underwent cardiac catheterization in our hospital between January 2017 and December 2020. The levels of the fibrotic markers, including type IV collagen 7s, procollagen type III peptide, and hyaluronic acid, were measured. Results Procollagen type III peptide was markedly elevated in infants younger than one year of age. From one to 15 years of age, it was slightly lower than in the infant group, with a peak at around 10 years of age. In the age group of 16 years and older, most of its values were generally high. Type IV collagen 7s and hyaluronic acid levels were high in infants, with no significant differences at later ages. Procollagen type III peptide and hyaluronic acid showed no significant correlation with CVP in any of the age groups, whereas type IV collagen 7s significantly correlated with CVP in the age group above one year old. Conclusions We found that elevated liver fibrosis markers, particularly type IV collagen 7s, correlated with central venous pressure in CHD patients older than one year. Measurement of liver fibrosis markers may allow the early detection of changes in CVP and liver function in patients with CHD.

A novel HECW2 variant in an infant with congenital long QT syndrome.

Pathogenic variants of HECW2 have been reported in cases of neurodevelopmental disorder with hypotonia, seizures, and absent language (NDHSAL; OMIM #617268). A novel HECW2 variant (NM_001348768.2:c.4343 T > C,p.Leu1448Ser) was identified in an NDHSAL infant with severe cardiac comorbidities. The patient presented with fetal tachyarrhythmia and hydrops and was postnatally diagnosed with long QT syndrome. This study provides evidence that HECW2 pathogenic variants can cause long QT syndrome along with neurodevelopmental disorders.

Liver T1/T2 values with cardiac MRI during respiration.

BACKGROUND: Assessing the hepatic status of children with CHD is very important in the post-operative period. This study aimed to assess the usefulness of paediatric liver T1/T2 values and to evaluate the impact of respiration on liver T1/T2 values. METHODS: Liver T1/T2 values were evaluated in 69 individuals who underwent cardiac MRI. The mean age of the participants was 16.2 ± 9.8 years. Two types of imaging with different breathing methods were possible in 34 participants for liver T1 values and 10 participants for liver T2 values. RESULTS: The normal range was set at 620-830 msec for liver T1 and 25-40 ms for liver T2 based on the data obtained from 17 healthy individuals. The liver T1/T2 values were not significantly different between breath-hold and free-breath imaging (T1: 769.4 ± 102.8 ms versus 763.2 ± 93.9 ms; p = 0.148, T2: 34.9 ± 4.0 ms versus 33.6 ± 2.4 ms; p = 0.169). Higher liver T1 values were observed in patients who had undergone Fontan operation, tetralogy of Fallot operation, or those with chronic viral hepatitis. There was a trend toward correlation between liver T1 values and liver stiffness (R = 0.65, p = 0.0004); and the liver T1 values showed a positive correlation with the shear wave velocity (R = 0.62, p = 0.0006). CONCLUSIONS: Liver T1/T2 values were not affected by breathing patterns. Because liver T1 values tend to increase with right heart overload, evaluation of liver T1 values during routine cardiac MRI may enable early detection of future complications.

Comparison of myocardial T1 mapping during breath-holding and free-breathing.

BACKGROUND: T1 mapping is a recently developed imaging analysis method that allows quantitative assessment of myocardial T1 values obtained using MRI. In children, MRI is performed under free-breathing. Thus, it is important to know the changes in T1 values between free-breathing and breath-holding. This study aimed to compare the myocardial T1 mapping during breath-holding and free-breathing. METHODS: Thirteen patients and eight healthy volunteers underwent cardiac MRI, and T1 values obtained during breath-holding and free-breathing were examined and compared. Statistical differences were determined using the paired t-test. RESULTS: The mean T1 values during breath-holding were 1211.1 ± 39.0 ms, 1209.7 ± 37.4 ms, and 1228.9 ± 52.5 ms in the basal, mid, and apical regions, respectively, while the mean T1 values during free-breathing were 1165.1 ± 69.0 ms, 1103.7 ± 55.8 ms, and 1112.0 ± 81.5 ms in the basal, mid, and apical regions, respectively. The T1 values were lower during free-breathing than during breath-holding in almost all segments (basal: p = 0.008, mid: p < 0.001, apical: p < 0.001). The mean T1 values in each cross section were 3.1, 7.8, and 7.7% lower during free-breathing than during breath-holding in the basal, mid, and apical regions, respectively. CONCLUSIONS: We found that myocardial T1 values during free-breathing were about 3-8% lower in all cross sections than those during breath-holding. In free-breathing, it may be difficult to assess myocardial T1 values, except in the basal region, because of underestimation; thus, the findings should be interpreted with caution, especially in children.

A Case Report of a Rare Heterozygous Variant in the Desmin Gene Associated With Hypertrophic Cardiomyopathy and Complete Atrioventricular Block.

Hypertrophic cardiomyopathy (HCM) is the primary cause of sudden cardiac death in children and adolescents. Patients with HCM frequently have ventricular tachycardia and ventricular fibrillation, although complete atrioventricular block (CAVB) is very rare. We report a case of HCM with CAVB in an 8-year-old girl who underwent transvenous implantable cardioverter-defibrillator placement after resuscitation. In this patient, we identified a de novo heterozygous missense variant, Arg406Trp (c.1216C > T), in the desmin (DES) gene. Pathogenic variants in the DES gene result in cardiomyopathy, conduction disorders, and skeletal muscle weakness. This recently identified variant may cause HCM with CAVB.

La cardiomyopathie hypertrophique (CMH) est la première cause de mort subite d'origine cardiaque chez les enfants et les adolescents. Les patients atteints de CMH présentent fréquemment une tachycardie ventriculaire et une fibrillation ventriculaire, bien que le bloc auriculo-ventriculaire complet (BAVC) soit très rare. Nous rapportons un cas de CMH avec BAVC chez une fillette de 8 ans qui a reçu un défibrillateur cardioverteur implantable par voie transveineuse après réanimation. Chez cette patiente, nous avons isolé un variant faux sens hétérozygote de novo, Arg406Trp (c.1216C > T), dans le gène de la desmine (DES). Les variants pathogènes du gène DES entraînent une cardiomyopathie, des troubles de la conduction et une faiblesse des muscles squelettiques. Ce variant récemment identifié peut causer une CMH avec BAVC.

Type IV Collagen 7s Reflects Central Venous Pressure and Right Ventricular End-Diastolic Pressure in Patients with Congenital Heart Disease After Biventricular Repair.

After congenital heart disease repair, right heart dysfunction facilitates venous stasis and elevated central venous pressure; however, methods to evaluate right heart dysfunction are limited. We aimed to evaluate right heart function using liver biomarkers. We investigated 62 patients more than 5 years after congenital heart surgery. The patients underwent cardiac catheterization in our hospital between January 2015 and December 2019. To evaluate liver status, type IV collagen 7s, procollagen type III peptide, and hyaluronic acid levels were measured. The mean age of the 62 patients was 14.0 ± 7.2 years. The mean central venous pressure was 6.8 ± 3.5 mmHg and mean right ventricular end-diastolic pressure was 7.9 ± 3.5 mmHg. The mean levels of serum type IV collagen 7s, procollagen type III peptide, and hyaluronic acid were 5.9 ± 1.6 ng/mL, 24.3 ± 15.5 ng/mL, and 18.5 ± 13.6 ng/mL, respectively. There was a good correlation between central venous pressure, right ventricular end-diastolic pressure and type IV collagen 7s (r = 0.67 and r = 0.64). There was no correlation between central venous pressure and the procollagen type III peptide (r = 0.003), and slight correlation between central venous pressure and hyaluronic acid (r = 0.31). There was no correlation between right ventricular end-diastolic pressure and the procollagen type III peptide (r = 0.003), and slight correlation between right ventricular end-diastolic pressure and hyaluronic acid (r = 0.31). We found that changes in the hemodynamics of the right heart system can be evaluated using liver fibrosis markers. Type IV collagen 7s reflects central venous pressure and right ventricular end-diastolic pressure in postoperative patients with congenital heart disease.