4D flow MRI-derived energy loss and RV workload in adults with tetralogy of Fallot.

PURPOSE: To assess flow energy loss (EL) pattern inside the pulmonary circulation in adult patients with repaired tetralogy of Fallot (TOF), particularly in TOF with pulmonary stenosis (PS) and pulmonary regurgitation (PR), as a cardiac workload parameter and its relationship to symptoms and major adverse cardiovascular events (MACE). METHODS: Prospectively, 51 consecutive TOF adults after intracardiac repair, who underwent four-dimensional flow magnetic resonance imaging, were enrolled. All of them had significant PR (PR regurgitant fraction >25 %). TOF patients who had already reached the conventional criteria were excluded. We defined MACE as the following: 1) fatal arrhythmias, 2) sudden cardiac death, 3) surgical pulmonary valvular repair (PVR), 4) right heart failure (HF) needing diuretics and/or hospitalization within 2 years. RESULTS: A total of 15 patients had MACE; 1) 10 patients underwent PVR within 2 years, 2) 2 patients had ventricular tachycardia, and 3) 6 patients developed right HF (overlapped). Right ventricular (RV) end diastolic volume index (EDVI), RV end systolic volume index (ESVI), average EL/cardiac output (CO), and diastolic EL/CO in patients with MACE were greater than ones without MACE. On a multivariate logistic analysis, the diastolic EL/CO ratio and RVEDVI had the highest odds with MACE in all TOF (odds ratio, 40.7 and 1.15. 95%CI, 1.83-905 and 1.02-13.0; p-value, 0.02 and 0.03). In sub-analysis within 29 patients with moderate PS with PR, and 10 patients with MACE showed higher diastolic EL/CO. Average and diastolic EL/CO negatively correlated with RV ejection fraction (EF) in this sub-analysis. CONCLUSIONS: High EL, particularly, high diastolic EL/CO, were the important factors for MACE in adult TOF. Higher diastolic EL/CO was also related to lower RV EF and deteriorated RV function in adult TOF with PS and PR. Right-sided EL can be a sensitive marker of excessive cardiac workload which integrates both afterload and preload in adult patients with TOF, beyond the RV size.

α/ß- and ß-Blocker Exposure in Pregnancy and the Risk of Neonatal Hypoglycemia and Small for Gestational Age.

BACKGROUND: α/ß- and ß-blockers are essential in pregnant women's perinatal congenital heart disease management. Nevertheless, data on the effects of α/ß- and ß-blockers on pregnant women and fetuses are limited. We examined the risks of neonatal hypoglycemia and small for gestational age (SGA) associated with maternal exposure to α/ß- and ß-blockers.Methods and Results: All consecutive pregnant women with heart disease admitted to our hospital between January 2014 and October 2020 were included. Of 306 pregnancies (267 women), 32 were in the α/ß-blocker group, 11 were in the ß-blocker group, and 263 were in the control group. All 32 pregnancies in the α/ß-blocker group were treated with carvedilol. In the ß-blocker group, 4 women were treated with bisoprolol, 3 were treated with propranolol, 2 were treated with atenolol, 1 was treated with metoprolol, and 1 was treated nadolol. The incidence of neonatal hypoglycemia was higher in pregnant women taking carvedilol than in the control group (P=0.025). SGA was observed significantly more frequently in pregnant women taking ß-blockers than in the carvedilol and control groups (P<0.001). CONCLUSIONS: Carvedilol administration during pregnancy was associated with neonatal hypoglycemia; however, it did not occur in a time- or dose-dependent manner. Routine monitoring of blood glucose levels in newborns exposed to α/ß- and ß-blockers is essential.

Predictors of liver cirrhosis and hepatocellular carcinoma among perioperative survivors of the Fontan operation.

OBJECTIVE: Fontan-associated liver disease (FALD) is widely recognised as a common complication in patients long after the Fontan operation. However, data on the predictors of FALD that can guide its screening and management are lacking. The present study aimed to identify the predictors of liver cirrhosis (LC) and hepatocellular carcinoma (HCC) in post-Fontan patients. METHODS: This was a multi-institutional retrospective cohort study. Clinical data of all perioperative survivors of Fontan operation before 2011 who underwent postoperative catheterisation were collected through a retrospective chart review. RESULTS: A total of 1117 patients (538 women, 48.2%) underwent their first Fontan operation at a median age of 3.4 years. Postoperative cardiac catheterisation was conducted at a median of 1.0 year. During a median follow-up period of 10.3 years, 67 patients (6.0%) died; 181 (16.2%) were diagnosed with liver fibrosis, 67 (6.0%) with LC, 54 (4.8%) with focal nodular hyperplasia and 7 (0.6%) with HCC. On multivariable analysis, high central venous pressure (CVP) (HR, 1.28 (95% CI 1.01 to 1.63) per 3 mm Hg; p=0.042) and severe atrioventricular valve regurgitation (HR, 6.02 (95% CI 1.53 to 23.77); p=0.010) at the postoperative catheterisation were identified as independent predictors of LC/HCC. CONCLUSIONS: Patients with high CVP and/or severe atrioventricular valve regurgitation approximately 1 year after the Fontan operation are at increased risk of developing advanced liver disease in the long term. Whether therapeutic interventions to reduce CVP and atrioventricular valve regurgitation decrease the incidence of advanced liver disease requires further elucidation.

Utility of urinary liver-type fatty acid-binding protein as a prognostic marker in adult congenital heart patients hospitalized for acute heart failure.

Progression to acute kidney injury (AKI) under treatment in adult congenital heart disease (ACHD) patients with heart failure is associated with poor prognosis, early detection and interventions are necessary. We aimed to explore the utility of urinary liver-type fatty acid binding protein (L-FABP) in ACHD patients hospitalized for acute decompensated heart failure (ADHF). We prospectively evaluated hemodynamic, biochemical data, and urinary biomarkers including urinary L-FABP in ACHD patients hospitalized in our institution from June 2019 to March 2022. The primary outcomes were the development of AKI and death. AKI was defined as serum creatinine level increased by 0.3 mg/dl or more within 5 days after hospitalization. A total of 104 ADHF patients aged 31 (36-51) years were enrolled. 26 cases (25% of ADHF patients) developed AKI during hospitalization and 4 died after hospital discharge. Serum creatinine (sCr), serum total bilirubin, brain natriuretic peptide (BNP), and urinary L-FABP in AKI patients were significantly higher than in non-AKI patients, whereas systemic oxygen saturation of the peripheral artery (SpO2) and estimated glomerular filtration ratio in AKI patients were lower than non-AKI patients. There was no difference in the intravenous diuretic dose on admission and during hospitalization between the two groups. In the receiver operating characteristic (ROC) analysis, the maximum area under the curve (AUC) of urinary biomarkers in AKI patients was urinary L-FABP (AUC = 0.769, p < 0.001) with a cutoff value of 4.86 µg/gCr. Urinary L-FABP level on admission was associated with a predictor for AKI development during hospitalization after adjusting for sCr, BNP and SpO2. Urinary L-FABP was a useful predictor for the development of AKI in ACHD patients hospitalized for ADHF. Monitoring of urinary L-FABP allows us to detect a high-risk patient earlier than the conventional biomarkers.

Abdominal lymphatic pathway in Fontan circulation using non-invasive magnetic resonance lymphangiography.

Lymphatic congestion is known to play an important role in the development of late Fontan complications. This study aimed to (1) develop a gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) contrast three-dimensional heavily T2-weighed MR technique that can detect abnormal lymphatic pathway in the abdomen while simultaneously evaluating hepatocellular carcinoma (HCC) and to (2) propose a new classification of abnormal abdominal lymphatic pathway using a non-invasive method in adults with Fontan circulation. Twenty-seven adults with Fontan circulation who underwent Gd-EOB-DTPA abdominal MR imaging were prospectively enrolled in this study. We proposed MR lymphangiography that suppresses the vascular signal on heavily T2-weighted imaging after EOB contrast. The patients were classified as follows: grade 1 with almost no lymphatic pathway, grade 2 with a lymphatic pathway mainly around the bile duct and liver surface, and grade 3 with a lymphatic pathway mainly around the vertebral body and inferior vena cava. The grade 3 group showed the lowest oxygen saturation level, highest central venous pressure, highest incidence of massive ascites, HCC, and focal nodular hyperplasia. This group also tended to have patients with the oldest age and highest cardiac index; however, the difference was not statistically significant. As for the blood test, the grade 3 group showed the lowest platelet count and serum albumin level and the highest fibrosis-4 index. A novel technique, Gd-EOB-DTPA MR lymphangiography, can detect abnormal abdominal lymphatic pathways in Fontan circulation, which can reflect the severity of failing Fontan.

Platelet volume indices correlate to severity of heart failure and have prognostic value for both cardiac and thrombotic events in patients with congenital heart disease.

Patients with heart failure (HF) reportedly have activated platelets with increased platelet distribution width (PDW) and mean platelet volume (MPV), which lead to thrombotic events. These platelet indices are easily measured by routine blood tests and have been proposed as potential markers of cardiac events. We performed the present study to clarify whether platelet indices correlate to the severity of HF and to the prognosis of patients with congenital heart disease (CHD). We performed a retrospective single-center study including 400 patients with CHD [median age, 34 years (range 12-76); 49% males] hospitalized between 2014 and 2017. We assessed their clinical data, correlation between platelet indices and severity of HF, and prognosis of HF-related hospitalization and thrombus formation. In multivariate analysis, a significant correlation was found between PDW and logBNP (log-transformed brain natriuretic peptide; r = 0.30, p < 0.001), as well as between MPV and logBNP (r = 0.24, p < 0.001). After treatment for heart failure, a significant reduction was found in PDW (average value before treatment: 14.2; after: 13.2, p = 0.017). In multivariate logistic regression analysis, PDW [hazard ratio (HR) 1.365; 95% confidence interval (CI) 1.005-1.768] and MPV (HR 1.472; 95% CI 1.055-2.052) were predictors of HF-related hospitalization. Similarly, PDW (HR 1.998; 95% CI 1.461-2.630) and MPV (HR 1.792; 95% CI 1.155-2.781) were predictors of thrombus formation. Platelet volume indices correlate to severity of heart failure and have prognostic value for both cardiac and thrombotic events in patients with CHD.

Risk factors for Fontan-associated hepatocellular carcinoma.

AIMS: The incidence of hepatocellular carcinoma (HCC) in patients with Fontan-associated liver disease (i.e., FALD-HCC) has increased over time. However, the risk factors for HCC development remain unclear. Here, we compared the levels of non-invasive markers to the survival rate of FALD-HCC patients. METHODS: From 2003 to 2021, 154 patients (66 men, 42.9%) developed liver disease after undergoing Fontan procedures. HCC was diagnosed in 15 (9.7%) (8 men, 53.3%) at a median age of 34 years (range, 21-45 years). We compared FALD-HCC and non-HCC cases; we generated marker level cutoffs using receiver operating characteristic curves. We sought to identify risk factors for HCC and mortality. RESULTS: The incidence of HCC was 4.9% in FALD patients within 20 years after the Fontan procedure. Compared with non-HCC patients, FALD-HCC patients exhibited higher incidences of polysplenia and esophageal varices. At the time of HCC development, the hyaluronic acid (HA) level (p = 0.04) and the fibrosis-4 index (p = 0.02) were significantly higher in FALD-HCC patients than in non-HCC patients; the total bilirubin (T-BIL) level (p = 0.07) and the model for end-stage liver disease score [excluding the international normalized ratio (MELD-XI)] (p = 0.06) tended to be higher in FALD-HCC patients. Within approximately 20 years of the Fontan procedure, 10 patients died (survival rate, 96.9%). Kaplan-Meier curve analysis indicated that patients with T-BIL levels ≥ 2.2 mg/dL, HA levels ≥ 55.5 ng/mL, and MELD-XI scores ≥ 18.7 were at high risk of HCC, a generally poor prognosis, and both polysplenia and esophageal varices. Multivariate Cox regression analyses indicated that the complication of polysplenia [Hazard ratio (HR): 10.915] and a higher MELD-XI score (HR: 1.148, both p < 0.01) were independent risk factors for FALD-HCC. CONCLUSIONS: The complication of polysplenia and a MELD-XI score may predict HCC development and mortality in FALD patients.

Reprocessing seafood waste: challenge to develop aquatic clean meat from fish cells.

Fish consumption has been increasing worldwide as per capita consumption of fish rises along with population growth. At the same time, overfishing is increasing all over the world, causing enormous damage to the ecosystem. There is an urgent need to secure sustainable fishery resources to meet the expanding demand for fish. The present study focused on the cells obtained from fish fins, which were often discarded as food waste, and which had the potential to change their morphology with simple treatments, creating the possibility of processing fish fin cells into clean meat (i.e., meat produced in vitro; artificial, lab-cultured meat using tissue engineering techniques). The fin-derived fibroblast-like cells demonstrated an interesting characteristic; changing the sera or culture media supported differentiation of the fibroblast-like cells to various cell morphologies, such as neurofilaments and adipocytes, etc., without genetic manipulation. Furthermore, it was possible to culture the cells in multi-layered and three-dimensional forms that were suitable for processing and shaping. Taking advantage of the cells' characteristics, 'aquatic clean meat' was produced successfully at the prototype stage. Our results suggest that fish fins, which are often treated as waste material, thus, are easy to procure, simple to process, and could be used to create a sustainable food resource.

Predictors of long-term mortality among perioperative survivors of Fontan operation.

AIMS: The criteria for 'good' Fontan haemodynamics have been poorly defined in relation to long-term outcomes. The aim of this study was to identify the risk factors for mortality among haemodynamic parameters obtained early after the Fontan operation. METHODS AND RESULTS: Clinical data of all perioperative survivors of the Fontan operation performed before 2011, from nine institutions, were collected through a retrospective chart review. In total, 1260 patients were included. The median age at the time of Fontan operation was 3.6 years. Post-operative cardiac catheterization was conducted in 1117 patients at a median period of 1.0 years after the operation. During the median follow-up period of 10.2 years, 107 patients died. The mortality rates at 10, 20, and 25 years after the operation were 5%, 12%, and 22%, respectively. On multivariable analysis, older age at the time of the operation {≥15 years, hazard ratio (HR) [95% confidence interval (CI)]: 3.2 (1.7-5.9)} and haemodynamic parameters obtained at post-operative catheterization, such as low ejection fraction [<30%, HR (95% CI): 7.5 (3.2-18)], low systemic oxygen saturation [<80%, HR (95% CI): 3.8 (1.6-9.1)], high central venous pressure [≥16 mmHg, HR (95% CI): 2.3 (1.3-3.9)], and low mean systemic arterial pressure [<60 mmHg, HR (95% CI): 3.0 (1.4-6.2)] were identified as independent predictors of mortality. The predictive model based on these parameters had a c-index of 0.75 at 10 years. CONCLUSIONS: Haemodynamic parameters obtained at a median period of 1.0 years, post-operatively, can accurately identify patients with a high mortality risk, who may need intensive management to improve long-term outcomes.

Management of pregnancy and delivery in women with transposition of the great arteries after atrial switch operation: A 16-year single-center experience.

AIM: This study aimed to summarize cases of successful pregnancy and delivery in patients with transposition of the great arteries (TGA) after atrial switch operation (ASO), to provide management, clinical experience, and maternal and fetal outcomes. METHODS: During a 16-year period (2004-2019), we experienced 30 pregnancies in 15 patients after ASO at our institution. We retrospectively reviewed the medical records of the patients. RESULTS: In 30 pregnancies, there were 21 (70%) live births, five (17%) miscarriages, and four (13%) artificial abortions. There were no maternal or neonatal deaths. Cardiac complications occurred in nine (43%) patients: deterioration of right ventricular (RV) function in one, symptomatic heart failure (HF) in three, supraventricular tachyarrhythmia requiring electrical cardioversion in two, sick sinus syndrome that required pacemaker implantation in two, and hemoptysis in one. Obstetric complications occurred in five (24%). Neonatal complications were premature births (delivery at <37 weeks of gestation) in 15 (71%), and birthweight <2500 g in 18 (86%). The mode of delivery consisted of vaginal delivery (VD) in five (24%), and cesarean section (CS) in 16 (76%). CONCLUSION: A high incidence of preterm CS and cardiac complications including deterioration of RV function was observed in patients who had undergone ASO for TGA.

Predictors of neo-aortic valve regurgitation in the long term after arterial switch operation.

Although arterial switch operations (ASOs) have been performed globally to repair d-transposition of the great arteries (d-TGA) in neonates and infants, few studies have been reported regarding the influence of the hemodynamics of patients with d-TGA who have undergone ASO on the development of neo-aortic valve regurgitation (AR). We aimed to investigate the relationship between the hemodynamics and development of AR after ASO in patients with d-TGA by catheter evaluation. This observational study screened 114 consecutive patients who underwent ASO for d-TGA or Taussig-Bing anomaly and who subsequently underwent catheter evaluations in our institution. We reviewed their records for the past 20 years and collected their first catheterization data post-ASO in early childhood. Thirty-six post-ASO patients who underwent catheter evaluations in both the early surgical and long-term phases were finally analyzed. Patients were divided into the following groups according to the presence of significant AR in the long-term phase: the AR group (n = 9 with AR ≥ grade II by the Sellers classification) and the non-AR group (n = 27 with AR < grade II). In the long-term phase, the diastolic blood pressure was significantly lower and the ascending aortic diameter was significantly larger in the AR group than in the non-AR group (p = 0.004 and p = 0.006, respectively). The systolic blood pressure (SBP) and pulse pressure (PP) were similar in both groups. Meanwhile, in the early surgical phase, SBP and PP were significantly higher in the AR group than in the non-AR group (p = 0.029 and p = 0.002, respectively). The receiver operating characteristic curve for late AR showed that the area under the curve for SBP and PP in the early surgical phase were 0.746 and 0.853, respectively. Even though sensitivity analysis was performed, SBP or PP greater than the cutoff value in the early surgical phase was identified as predictors for late AR. Our results suggested that high SBP or PP in the early surgical phase could influence the development of AR in the long term after ASO.

Pregnancy and Delivery in Patients With Repaired Congenital Heart Disease　- A Retrospective Japanese Multicenter Study.

BACKGROUND: Although advances in cardiac surgery have led to an increased number of survivors with congenital heart disease (CHD), epidemiological data regarding the pregnancies and deliveries of patients with repaired CHD are scarce.Methods and Results:In this study, we retrospectively reviewed the clinical outcomes of pregnancies and deliveries of women with repaired CHD. Overall, 131 women with repaired CHD were enrolled and there were 269 gestations. All patients were classified as New York Heart Association (NYHA) Class I or II. The prevalence of cesarean sections was higher in patients with (CyCHD) than without (AcyCHD) a past history of cyanosis (51% vs. 19%, respectively; P<0.01). There were 228 offspring from 269 gestations and the most prevalent neonatal complication was premature birth (10%), which was more frequent in the CyCHD than AcyCHD group (15.7% vs. 5.6%, respectively; P<0.01). Five maternal cardiac complications during delivery were observed only in the CyCHD group (8%); these were classified as NYHA Class II and none was fatal. CONCLUSIONS: Delivery was successful in most women with repaired CHD who were classified as NYHA Class I or II, although some with CyCHD and NYHA Class II required more attention. Cesarean sections were more common in the CyCHD than AcyCHD group, and CyCHD may be a potential risk for preterm deliveries.

Skeletal muscle index determined by bioelectrical impedance analysis is a determinant of exercise capacity and a prognostic predictor in patients with congenital heart disease.

BACKGROUND: Patients with congenital heart disease (CHD) reportedly have reduced exercise capacity. Underlying cardiac anatomy and a sedentary lifestyle are thought to be associated with exercise impairment. However, little has been reported regarding the relationship between quantitative body composition and exercise capacity. Bioelectrical impedance analysis (BIA) is a rapid and safe assessment method that has been widely used in clinical research. We hypothesized that bioelectrical impedance parameters are determinants of exercise capacity, and the skeletal muscle index (SMI) determined by BIA is a prognostic predictor in patients with CHD. METHODS: We conducted a retrospective single-center study of 305 consecutive patients with CHD [median age, 26 years (range 12-60]; 48% males] admitted between 2014 and 2017. The BIA parameters were reviewed, including the edema index (EI, extracellular water to total body water ratio), SMI (skeletal muscle mass/height2), mineral index (MI, mineral mass/height2), percent body fat (%BF), and exercise capacity [peak oxygen uptake (peakVO2)] via a cardiopulmonary exercise test. RESULTS: The multivariate analysis revealed a significant correlation between peakVO2 and EI (r=0.55) and peakVO2 and SMI (r=0.49). The receiver operating characteristic curve analysis showed that the EI cut-off for peakVO2<20ml/kg/min was 0.386 [area under the curve (AUC), 0.77; sensitivity, 0.67; specificity 0.76], and the SMI cut-off was 7.6kg/m2 (AUC, 0.78; sensitivity, 0.76; specificity 0.75). Compared with patients who had biventricular morphology, patients with single ventricular morphology had a higher EI (mean, 0.381 vs. 0.387, respectively) and lower SMI (8.5 vs. 7.7, respectively), resulting in a lower peakVO2 (27.1 vs. 20.8, respectively). The Kaplan-Meier analysis showed that a low SMI was associated with an increased risk of future heart failure-related admissions. CONCLUSIONS: SMI determined by BIA is a determinant of exercise capacity and can be used as a prognostic predictor in patients with CHD.

Clinical Significance of Central Venous Pressure During Exercise After Fontan Procedure.

Various late complications are associated with the Fontan procedure. In patients who undergo the Fontan procedure, the central venous pressure (CVP) tends to be higher than normal. However, the relationship between CVP (at rest and during exercise) and late complications associated with the Fontan procedure is unknown. Thirty-four patients who underwent the Fontan procedure were enrolled in this study. The median age was 19.3 years, and the median time after the Fontan procedure was 12.7 years. With exercise, the CVP increased from a median of 11 to 19 mmHg, and the cardiac index increased from a median of 2.1 to 4.4 l/min/m2. In 38% of the patients, CVP measured at the resting condition and during exercise differed. Laboratory results indicated no significant difference between the patients in the high-CVP group and low-CVP group at rest. In contrast, during exercise, brain natriuretic peptide (67 ± 38 vs. 147 ± 122 pg/ml, p < 0.05), gamma-glutamyl transpeptidase (63 ± 33 vs. 114 ± 30 IU/l, p < 0.05), type IV collagen 7S (6.7 ± 1.3 vs. 8.1 ± 1.3 ng/ml, p < 0.05), and creatinine (0.72 ± 3.14 vs. 0.83 ± 3.16 mg/dl, p < 0.05) levels were significantly higher in the high-CVP group than in the low-CVP group. Elevated CVP during exercise may be associated with long-term complications after the Fontan procedure; hence, CVP should be measured during exercise in patients who underwent the Fontan procedure to accurately predict the risk of developing such complications.

Early and Late Effects of Cardiac Resynchronization Therapy in Adult Congenital Heart Disease.

Background There are limited data about cardiac resynchronization therapy (CRT) in adult congenital heart disease. We aimed to assess early and late outcomes of CRT among patients with adult congenital heart disease. Methods and Results We retrospectively studied 54 patients with adult congenital heart disease (median age, 46 years; range, 18-73 years; 74% men) who received CRT implantation (biventricular paced >90%) between 2004 and 2017. Clinical and echocardiographic data were analyzed at baseline and early (mean±SD: 1.8±0.8 years) and late (4.7±0.8 years) follow-up after CRT. Compared with baseline, CRT was associated with significant improvement at early follow-up in New York Heart Association functional class, QRS duration, and cardiothoracic ratio (P<0.05 for all); improvement in New York Heart Association class was sustained at late follow-up. Among patients with a systemic left ventricle (LV; n=39), there was significant increase in LV ejection fraction and reduction in LV end-systolic volume at early and late follow-up (P<0.05 for both). For patients with a systemic right ventricle (n=15), there was a significant early but not late reduction in systemic right ventricular basal and longitudinal diameters. Eleven patients died, and 2 had heart transplantation unrelated to systemic ventricular morphological characteristics. Thirty-five patients (65%) responded positively to CRT, but only baseline QRS duration was predictive of a positive response. Conclusions CRT results in sustained improvement in functional class, systemic LV size, and function. Patients with a systemic LV and prolonged QRS duration, independent of QRS morphological characteristics, were most likely to respond to CRT.

PNPase knockout results in mtDNA loss and an altered metabolic gene expression program.

Polynucleotide phosphorylase (PNPase) is an essential mitochondria-localized exoribonuclease implicated in multiple biological processes and human disorders. To reveal role(s) for PNPase in mitochondria, we established PNPase knockout (PKO) systems by first shifting culture conditions to enable cell growth with defective respiration. Interestingly, PKO established in mouse embryonic fibroblasts (MEFs) resulted in the loss of mitochondrial DNA (mtDNA). The transcriptional profile of PKO cells was similar to rho0 mtDNA deleted cells, with perturbations in cholesterol (FDR = 6.35 x 10-13), lipid (FDR = 3.21 x 10-11), and secondary alcohol (FDR = 1.04x10-12) metabolic pathway gene expression compared to wild type parental (TM6) MEFs. Transcriptome analysis indicates processes related to axonogenesis (FDR = 4.49 x 10-3), axon development (FDR = 4.74 x 10-3), and axonal guidance (FDR = 4.74 x 10-3) were overrepresented in PKO cells, consistent with previous studies detailing causative PNPase mutations in delayed myelination, hearing loss, encephalomyopathy, and chorioretinal defects in humans. Overrepresentation analysis revealed alterations in metabolic pathways in both PKO and rho0 cells. Therefore, we assessed the correlation of genes implicated in cell cycle progression and total metabolism and observed a strong positive correlation between PKO cells and rho0 MEFs compared to TM6 MEFs. We quantified the normalized biomass accumulation rate of PKO clones at 1.7% (SD ± 2.0%) and 2.4% (SD ± 1.6%) per hour, which was lower than TM6 cells at 3.3% (SD ± 3.5%) per hour. Furthermore, PKO in mouse inner ear hair cells caused progressive hearing loss that parallels human familial hearing loss previously linked to mutations in PNPase. Combined, our study reports that knockout of a mitochondrial nuclease results in mtDNA loss and suggests that mtDNA maintenance could provide a unifying connection for the large number of biological activities reported for PNPase.

Influence of pregnancy on cardiac function and hemodynamics in women with Ebstein's anomaly.

INTRODUCTION: We examined the perinatal outcomes and right ventricular function before pregnancy, during pregnancy, and after delivery in women with Ebstein's anomaly. MATERIAL AND METHODS: We retrospectively investigated the clinical course and mode of delivery and monitored hemodynamic parameters throughout pregnancy in 17 women with Ebstein's anomaly who delivered at our institution during the period of 1995-2015. RESULTS: Eight women, including nine pregnancies, underwent elective cesarean section, and nine women, including 14 pregnancies, underwent vaginal delivery. Elective cesarean section was performed in cases with significant heart failure or arrhythmias and in the presence of more than two of the following: cardiothoracic ratio ≥60%, moderate or severe tricuspid valve regurgitation, tricuspid valve regurgitation pressure gradient ≥35 mmHg during pregnancy. The cardiothoracic ratio and tricuspid valve regurgitation pressure gradient significantly increased during pregnancy compared with prepregnancy values. The New York Heart Association classification deteriorated from class I to class II or III in five cases during pregnancy. CONCLUSIONS: Although pregnancy was relatively safe among women with Ebstein's anomaly, some women developed cyanosis, arrhythmia, and heart failure, leading to elective cesarean section. Monitoring clinical and hemodynamic changes throughout pregnancy is advised to minimize maternal cardiac risk and select the appropriate mode of delivery.