Palmitoylation of ULK1 by ZDHHC13 plays a crucial role in autophagy.

Autophagy is a highly conserved process from yeast to mammals in which intracellular materials are engulfed by a double-membrane organelle called autophagosome and degrading materials by fusing with the lysosome. The process of autophagy is regulated by sequential recruitment and function of autophagy-related (Atg) proteins. Genetic hierarchical analyses show that the ULK1 complex comprised of ULK1-FIP200-ATG13-ATG101 translocating from the cytosol to autophagosome formation sites as a most upstream ATG factor; this translocation is critical in autophagy initiation. However, how this translocation occurs remains unclear. Here, we show that ULK1 is palmitoylated by palmitoyltransferase ZDHHC13 and translocated to the autophagosome formation site upon autophagy induction. We find that the ULK1 palmitoylation is required for autophagy initiation. Moreover, the ULK1 palmitoylated enhances the phosphorylation of ATG14L, which is required for activating PI3-Kinase and producing phosphatidylinositol 3-phosphate, one of the autophagosome membrane's lipids. Our results reveal how the most upstream ULK1 complex translocates to the autophagosome formation sites during autophagy.

Long-term outcomes of functional single ventricles associated with heterotaxy syndrome†.

OBJECTIVES: The goal of this study was to determine the long-term surgical outcomes of patients with functional single ventricles associated with heterotaxy syndrome, risk factors for mortality and factors associated with Fontan stage completion. METHODS: Overall, 279 patients with a functional single ventricle associated with heterotaxy syndrome who underwent an initial surgical procedure at our institute between 1978 and 2021 were grouped into 4 "eras" based on the surgical year during which the initial procedure was performed: era 1 (1978-1989, n = 71), era 2 (1990-1999, n = 98), era 3 (2000-2009, n = 64) and era 4 (2010-2021, n = 46). Neonatal surgery was more frequent in eras 3 and 4 than in eras 1 and 2. RESULTS: Overall, 228 patients had right atrial isomerism; 120 patients (43.0%) had a total anomalous pulmonary venous connection; and 58 patients (20.8%) underwent an initial procedure as neonates. Overall survival rates at 10, 20 and 30 years after the initial procedure were 47.1%, 40.6% and 36.1%, respectively. Neonatal surgery (P < 0.001), total anomalous pulmonary venous connection repair at the initial procedure (P < 0.001) and early era (P < 0.001) were identified as risk factors for mortality, with the last 2 variables being negatively associated with Fontan stage completion (P < 0.001 for both). CONCLUSIONS: Although era had a favourable effect on survival, total anomalous pulmonary venous connection with intrinsic pulmonary vein obstruction was associated with both mortality and Fontan stage completion. CLINICAL REGISTRATION NUMBER: R19092.

Death, reoperation, and late cardiopulmonary function after truncus repair.

Objective: To identify the late surgical outcomes of truncus arteriosus. Methods: Fifty consecutive patients with truncus arteriosus who underwent surgery between 1978 and 2020 at our institute were enrolled in this retrospective, single institutional cohort study. The primary outcome was death and reoperation. The secondary outcome was late clinical status, including exercise capacity. The peak oxygen uptake was measured by a ramp-like progressive exercise test on a treadmill. Results: Nine patients underwent palliative surgery, which resulted in 2 deaths. Forty-eight patients went on to truncus arteriosus repair, including 17 neonates (35.4%). The median age and body weight at repair were 92.5 days (interquartile range, 10-272 days) and 3.85 kg (interquartile range, 2.9-6.5 kg), respectively. The survival rate at 30 years was 68.5%. Significant truncal valve regurgitation (P = .030) was a risk factor for survival. Survival rates were similar between in the early 25 and late 25 patients (P = .452). The freedom from death or reoperation rate at 15 years was 35.8%. Significant truncal valve regurgitation was a risk factor (P = .001). The mean follow-up period in hospital survivors was 15.4 ± 12 years (maximum, 43 years). The peak oxygen uptake, which was performed in 12 long-term survivors at a median duration from repair of 19.7 years (interquartile range, 16.8-30.9 years), was 70.2% of predicted normal (interquartile range, 64.5%-80.4%). Conclusions: Truncal valve regurgitation was a risk factor for both survival and reoperation, thus improvement of truncal valve surgery is essential for better life prognosis and quality of life. Slightly reduced exercise tolerance was common in long-term survivors.

Patient-Prosthesis Mismatch Associated With Somatic Growth After Mechanical Mitral Valve Replacement in Small Children: Metrics for Reoperation and Outcomes.

Reoperation after pediatric mitral valve replacement (MVR) is inevitable due to patient-prosthesis mismatch (PPM) associated with somatic growth. We analyzed potential metrics for PPM and outcomes of redo MVR for valve upsizing. Between 1999 and 2018, 15 children without obstructive left heart lesions other than mitral stenosis underwent initial MVR with a 16-mm ATS-Advanced Performance valve. We analyzed hemodynamic data from 28 postoperative catheterizations and concomitant echocardiograms. The median age and body weight at initial MVR were 4.9 months (25th, 75th percentile: 3.6, 6.6) and 5.9 kg (5.0, 7.3). Redo MVR was planned when patients had congestive heart failure and postcapillary pulmonary hypertension (PH) due to PPM: systolic pulmonary arterial pressure (SPAP) >35 mm Hg and pulmonary capillary wedge pressure (PCWP) >15 mm Hg on catheterization. Indexed effective orifice area (iEOA) and mean transmitral pressure gradient (TMPG) were strongly correlated with SPAP (r = -0.72, P < 0.001 and r = 0.75, P < 0.001) and PCWP (r = -082, P < 0.001 and r = 0.84, P < 0.001). Cut-off values for detecting postcapillary PH due to PPM were 1.0 cm2/m2 for iEOA and 18 mm Hg for mean TMPG. Nine patients underwent redo MVR for postcapillary PH due to PPM at a median postoperative interval of 10 years (9.2, 11.9). All the patients survived, and PH was improved one year after surgery. iEOA and mean TMPG can be metrics for PPM in children after MVR. Careful follow-up is required to confirm the improvement of preoperatively existing PH after redo MVR for valve upsizing.

Comparison of long-term outcomes of atrial switch with Rastelli and physiological repair using left ventricle-to-pulmonary artery conduit for levo-transposition of the great arteries.

OBJECTIVES: The objectives of this study was to compare the long-term outcomes of anatomic repair using atrial switch with the Rastelli procedure versus physiological repair with left ventricle-to-pulmonary artery conduit for patients with levo-transposition of the great arteries, ventricular septal defect, and left ventricular outflow tract obstruction. METHODS: Of patients with levo-transposition of the great arteries who underwent biventricular repair between 1978 and 2001, 31 hospital survivors after anatomic repair of atrial switch and the Rastelli (anatomic group) and 14 hospital survivors after physiological repair with left ventricle-to-pulmonary artery conduit (physiological group) were enrolled. Survival rates, reoperation rates, and most recent conditions were compared. RESULTS: The overall survival rate at 20 years was 79.7% (95% CI, 66.4%-95.6%) in the anatomic group and 85.1% (95% CI, 68.0%-100%) in the physiological group (P = .87). The reoperation rate at 10 years was 19.8% (95% CI, 5.6%-34.0%) in the anatomic group and 52.0% (95% CI, 25.0%-79.1%) in the physiological group (P = .067). Only patients in the physiological group underwent systemic tricuspid valve replacement. The anatomic group showed a better cardiac index at catheterization (2.79 ± 0.75 L/min/m2 vs 2.30 ± 0.54 L/min/m2; P = .035), lower serum brain natriuretic peptide (73 ± 86 pg/mL vs 163 ± 171 pg/mL; P = .024), and better maximal oxygen uptake in the treadmill test (64.1 ± 16.5% vs 52.7 ± 17.8% of predicted normal; P = .036), although the period until most recent catheterization, blood inspection, and treadmill testing were earlier in the anatomic group. CONCLUSIONS: Preservation of the left ventricle as the systemic ventricle using anatomic repair contributes to better cardiopulmonary condition compared with physiological repair.

Long-Term Influence of Atrial Switch Operation on Hemodynamics After the Rastelli Procedure.

The study aimed to investigate the long-term influence of atrial switch on post-Rastelli hemodynamic condition. Of 112 patients with transposition of the great arteries (TGA) or TGA-type double outlet right ventricle, ventricular septal defect (VSD), and pulmonary stenosis (PS) who underwent intra-cardiac repair between 1979 and 2018, 50 patients with levo-TGA underwent atrial switch and Rastelli as an anatomic repair and 62 patients with dextro-TGA underwent Rastelli. Postoperative outcomes were retrospectively compared. The median follow-up durations were 20.1 years (interquartile range: 4.3, 32.4) in the Rastelli group and 15.3 years (7.1, 23.0) in the atrial switch plus Rastelli group (p = 0.19). Sex, age, and weight at operation were similar in both groups. Overall survival rates at 30 years were 69.8% in the Rastelli group and 80.1% in the atrial switch plus Rastelli group (p = 0.18). The atrial switch plus Rastelli group required more frequent catheter interventions (p < 0.001), mainly for caval obstruction (n = 8) and atrial arrhythmia (n = 6). Medication was more frequent in the atrial switch plus Rastelli group (p = 0.009). Exercise capacity was similarly reduced in two groups. Protein-losing enteropathy (PLE) occurred in three long-term survivors in the atrial switch plus Rastelli group (p = 0.07). Concomitantly performed atrial switch operation did not affect long-term survival and exercise capacity after Rastelli procedure. However, the occurrence of PLE, a frequent need for medication, and catheter interventions after atrial switch plus Rastelli may result from atrial switch under the post-Rastelli condition.

Impact of right ventriculotomy for tetralogy of Fallot repair with a pulmonary valve-sparing procedure.

Objectives: The study objectives were to reconfirm the superiority of the pulmonary valve-sparing procedure versus the transannular patch procedure for repair of tetralogy of Fallot and to evaluate the influence of a right ventriculotomy in the pulmonary valve-sparing procedure. Methods: Between 1978 and 2003, 440 patients (aged <10 years) underwent tetralogy of Fallot repair. Of these patients, 242 (55.0%) underwent the transannular patch procedure, 106 (24.1%) underwent the pulmonary valve-sparing procedure without right ventriculotomy, and 92 (20.9%) underwent the pulmonary valve-sparing procedure with right ventriculotomy. End points focused on adverse events and included all-cause mortality, reoperation, catheter intervention, and symptomatic arrhythmias. To compare the outcomes of pulmonary valve sparing with and without right ventriculotomy, inverse probability weighting was applied to adjust for potential confounding factors. Results: The median follow-up period was 20.3 years (interquartile range, 10.7-27.6). In all cohorts, the pulmonary valve-sparing procedure was the independent factor that reduced adverse events after tetralogy of Fallot repair (hazard ratio, 0.47; 95% confidence interval, 0.23-0.94; P = .033). After weighting, there was no difference in overall survival or event-free survival in the pulmonary valve-sparing with and without right ventriculotomy group. However, the pulmonary valve-sparing with right ventriculotomy group exhibited a larger cardiothoracic ratio (beta: 6.01; 95% confidence interval, 2.36-9.66; P = .001), lower medication-free rate (odds ratio, 0.29; 95% confidence interval, 0.098-0.79; P = .019), and higher New York Heart Association functional classification (odds ratio, 2.99; 95% confidence interval, 1.36-6.80; P = .007) at the latest follow-up. Conclusions: Right ventriculotomy for tetralogy of Fallot repair with pulmonary valve-sparing did not increase major adverse events. However, negative impacts on current status cannot be ignored.

Short-term outcomes of EXCOR Paediatric implantation.

OBJECTIVES: The aim of this study was to review a single institution's experience with EXCOR Paediatric implantation. METHODS: Patients <15 years old who underwent EXCOR implantation as a bridge to transplantation between 2015 and 2021 were enrolled. Major adverse events included death, cerebrovascular event resulting in sequelae, major infection (sepsis or surgical site infection requiring open sternal irrigation or device removal) and device malfunction requiring surgical treatment. RESULTS: Overall median age and weight for all 20 children at implantation were 10.8 (interquartile range, 7.9-33.2) months and 6.3 (4.6-10.2) kg. Ten patients (50%) weighed <5 kg. Primary diagnoses were dilated cardiomyopathy in 13 patients, fulminant myocarditis in 3, restrictive cardiomyopathy in 2 and congenital heart disease in 2. Two patients required biventricular assist support. The median support time was 365 (241-636) days. Six patients (30%) were supported for >20 months. One patient died. Seven patients underwent heart transplant. Heart transplant has not been performed in the last 1.5 years. Five patients were weaned from EXCOR support after native myocardial recovery, including a patient with dilated cardiomyopathy who recovered after 24 months of EXCOR support. Major complication-free survival at 6, 12 and 18 months were 79.3%, 49.6% and 38.6%, respectively. Body weight <5 kg at implantation was a risk factor for decreased major complication-free survival. CONCLUSIONS: Survival during EXCOR Paediatric support was good, but it prolonged the wait time for a heart transplant. The number of major complications increased over time and was not negligible, especially in small children.

Intermediate-term outcomes of deferred Norwood strategy.

OBJECTIVE: The aim of this study was to assess outcomes of the deferred Norwood strategy, i.e. planned Norwood following routine bilateral pulmonary artery banding and ductal stenting or continuous prostaglandin E1 administration. METHODS: Forty-five patients with hypoplastic left heart syndrome and its variants treated with the deferred Norwood strategy between 2012 and 2021 were enrolled. Mid-term outcomes were retrospectively reviewed. The median follow-up period after Norwood in hospital survivors was 4.6 years (interquartile range: 1.9, 6.8). RESULTS: Fourteen patients (31.1%) had no risk factors. The median age and weight at Norwood were 1.8 months (0.9, 3.5) and 3.1 kg (2.7, 3.6). Transplant-free survival at 6 years was 84.5%. Birth weight ≤2.5 kg and systemic atrioventricular valve (SAVV) regurgitation ≥ moderate after birth were not risk factors for mortality; body weight at Norwood ≤2.5 kg, however, was a risk factor [hazard ratio (HR), 11.3; 95% confidence interval (CI), 1.2-11; P = 0.036]. Twenty-two (48.9%) underwent Fontan with no mortalities, and 7 (15.5%) are awaiting Fontan. Freedom from SAVV surgery at 5 years was 53.1%. SAVV regurgitation ≥ moderate after birth was a risk factor for SAVV surgery (HR, 16; 95% CI, 3.6-71; P < 0.001); however, ductal stenting had a protective effect against SAVV surgery (HR, 0.09; 95% CI, 0.01-0.68; P = 0.019). Freedom from both surgical and catheter-based pulmonary artery intervention at 3 years was 27.1. CONCLUSIONS: Although deferred Norwood provided acceptable intermediate-term survival, the Fontan completion rate was unsatisfactory. SAVV surgery and pulmonary artery intervention were frequently required.