Minimized Hemodiafiltration for Extracorporeal Membrane Oxygenation in Infants.

BACKGROUND: Fluid overload is a serious complication in the treatment of infants with extracorporeal membrane oxygenation (ECMO). Volume overload leads to prolonged ECMO therapy if left untreated. The renal replacement therapy of choice in pediatric patients is peritoneal dialysis or conventional dialysis using a "large" hemofiltration machine via a Shaldon catheter or directly connected to the ECMO system. This study describes the implementation of a novel minimized hemodiafiltration (HDF) system in pediatric patients on ECMO. METHODS: This retrospective analysis included 13 infants up to 5 kg who underwent 15 veno-arterial (V-A) ECMO runs with HDF. A minimized HDF system is integrated into an existing ECMO system (18-mL priming volume), connected post-oxygenation to the venous line, before the ECMO pump. Two infusion pumps are attached to the inlet and outlet of the hemofilter to control the HDF system.In addition to retention values (creatine and urea) at six defined time points, flow rates, dialysis parameters, and volume withdrawal were examined, as well as the number of HDF system changes. RESULTS: With a mean ECMO runtime of 156 hours, the HDF system was utilized for 131 hours. The mean blood flow through the hemofilter was 192 mL/min. The mean dialysate flow was 170 mL/h, with a mean volume deprivation of 39 mL/h. The HDF system was changed once in seven cases and twice in three cases. CONCLUSION: There were no complications with the minimized HDF system in all 15 applications. It allows safe patient volume management when treating infants with ECMO, with effective elimination of urinary substances.

Long-Term Results after Fallot Repair.

BACKGROUND: The aim of this study was to evaluate the long-term outcome and freedom from pulmonary valve replacement (PVR) after initial repair of tetralogy of Fallot (TOF). PATIENTS AND METHODS: The cohort of 306 patients treated between 1980 and 2017 was divided into anatomical subgroups according to the diagnosis of TOF-pulmonary stenosis, TOF-pulmonary atresia and TOF-double outlet right ventricle. Patients were treated with transannular patch (TAP), valve sparing repair (VSR), or conduits from the right ventricle to the pulmonary arteries (RVPA conduits). RESULTS: There were 21 deaths (6.9%), 14 being hospital deaths (4.6%) after primary correction and four deaths (1.3%) occurred after PVR. One patient died after a non-cardiac operation (0.3%). There were two late deaths (0.7%). During the past 12 years no early mortality has been observed. Ninety-one patients (30.4%) received PVR after a median of 12.1 ± 7.0 years with an early mortality of 4.4% (n = 4) and no late mortality. A significant difference in freedom from reoperation after TAP, VSR, and RVPA-conduits could be identified. Multivariate analysis displayed transannular repair (p = 0.016), primary palliation (p <0.001), the presence of major aortopulmonary collateral arteries (MAPCA; p = 0.023), and pulmonary valve Z-scores < - 4.0 (p = 0.040) as significant risk factors for PVR. CONCLUSION: TOF repair has a beneficial long-term prognosis with low morbidity and mortality. Pulmonary valve Z-scores < - 4.0, transannular repair, and presence of MAPCAs are associated with earlier PVR. Non-VSRs and TOF-pulmonary atresia lead to earlier reoperation but have no negative impact on survival.

Repair of common arterial trunk: palliation and delayed correction as a viable alternative strategy in selected patients.

OBJECTIVES: Primary repair of common arterial trunk (CAT) is burdened by high mortality rates, especially in the presence of multiple risk factors. Timing, possible palliative methods, optimal management of associated cardiac lesions and handling of a poor preoperative state are still under discussion. METHODS: We retrospectively analysed all patients who underwent surgery for CAT in our institution between 2008 and November 2020. We included 22 patients, 11 of whom received primary correction (PC) and 11 of whom underwent initial palliation by partial repair, leaving the ventricular septal defect open and connecting the right ventricle to the pulmonary arteries with a small valveless right ventricle-to-pulmonary artery conduit. A delayed correction (DC) was performed after 11.5 ± 3.6 months. RESULTS: The overall operative mortality was 4.5%; 1 patient (affected by severe truncal valve stenosis and presenting in a poor state preoperatively) in the DC group died after palliation. The incidence of postoperative pulmonary hypertensive crisis was significantly higher in the PC group (P = 0.027). No patient from either group required postoperative extracorporeal support. Survival rates after 6 years differed slightly (PC group, 90%; DC group, 70%; log-rank = 0.270). CONCLUSIONS: PC of CAT remains an optimal surgical approach for patients with an expected low mortality. However, our data support palliation and DC as a suitable alternative strategy, especially in the presence of significant risk factors like interrupted aortic arch, poor preoperative condition or complex surgical anatomy.

Systemic-to-pulmonary artery shunting using heparin-bonded grafts.

OBJECTIVES: Systemic-to-pulmonary artery shunting remains an important palliative procedure in the staged management of complex congenital heart defects. The use of heparin-bonded polytetrafluoroethylene shunts (HBPSs) should enhance graft patency. This study aimed to review the single-centre experience using HBPS in the context of congenital cardiac surgery. METHODS: The records of 51 patients treated using HBPS between 2010 and 2016 were retrospectively reviewed. The median age and weight of the patients were 8 (range 3-83) days and 3.2 (range 1.8-5.7) kg, respectively. Selected shunt size was 3.5 mm in all patients. Fourteen (27.5%) patients were planned for future biventricular repair and 37 (72.5%) patients underwent univentricular pathway. Shunt modifications included central aortopulmonary shunts (n = 35; 68.6%) and modified Blalock-Taussig shunts (n = 16; 31.4%). Shunt patency and survival until estimated 2nd procedure were calculated using the Kaplan-Meier method. RESULTS: Shunt patency was 90 ± 4% after a median duration of 133 (range 0-315) days. Early mortality (30 days) was 3.9% (n = 2). Another 3 patients died during their hospital stay. All the deceased patients had univentricular morphology, and the cause of death was not shunt related in all patients. Five patients developed subtotal HBPS thrombosis intraoperatively (n = 3), early postoperatively after 3 days (n = 1, 1.9%) or late after 41 days (n = 1, 1.9%). Treatment of those patients comprised right ventricular outflow tract opening (n = 2, 3.9%) or new shunting (n = 3, 5.9%). Elective shunt takedown was performed during corrective surgery (n = 10, 19.6%), bidirectional Glenn (n = 25, 49%) or shunt replacement (n = 5, 9.8%). At the end of follow-up, 1 (1.9%) patient had still an HBPS in situ. The survival rate until planned 2nd procedure was 87 ± 6% in univentricular patients and 100% in biventricular patients (P = 0.17). CONCLUSIONS: The use of HBPS in the context of palliative heart surgery is safe and seems to warrant a long-term patency of systemic-to-pulmonary shunts. However, by acting on only 1 site of Virchow's triad, shunt thrombosis, occurring predominantly early, cannot be totally excluded.

Prolonged prostaglandin E1 therapy in a neonate with pulmonary atresia and ventricular septal defect and the development of antral foveolar hyperplasia and hypertrophic pyloric stenosis.

Prostaglandin E1 (alprostadil) is widely used for maintaining the patency of ductus arteriosus in ductus-dependent congenital heart defects in neonates to improve oxygenation. Among more common side effects are fever, rash, apnoea, diarrhoea, jitteriness, and flushing. More severe side effects are brown fat necrosis, cortical hyperostosis, and gastric outlet obstruction, most commonly the result of antral foveolar hyperplasia or hypertrophic pyloric stenosis. We report on an infant with a ductus-dependent congenital heart defect who developed symptoms and sonographic evidence of focal foveolar hyperplasia and hypertrophic pyloric stenosis after prolonged treatment with prostaglandin E1. Gastrointestinal symptoms persisted after corrective cardiac surgery, and pyloromyotomy was required. Study of the case and of available literature showed an association between the total dose of prostaglandin E1 administered and duration of treatment and the development of gastric outlet obstruction. We conclude that if patients are treated with a prostaglandin E1 infusion, careful monitoring for symptoms and signs of gastric outlet obstruction is required.