Left axillary approach for pulmonary valve replacement.

A 14-year-old girl was scheduled for pulmonary valve replacement. A computed tomography scan showed an enlarged cardiac silhouette with an aneurysmal pulmonary artery. A less-invasive approach through the left axilla with peripheral cannulation was selected. The patient was draped in the decubitus position, with a roll under the left shoulder and the left arm over the head. The anatomical landmarks were the left nipple and the tip of the scapula. A 5-cm vertical incision in the mid-axillary line was performed, and the thorax was entered through the fourth intercostal space. Peripheral cannulation for cardiopulmonary bypass was achieved by a right groin dissection. Partial bypass was instituted and, on an unloaded heart, the ascending aorta plus the right appendage and the pulmonary artery were further cannulated. With the heart beating, the pulmonary artery was opened, and a 25-mm biological Carpentier Perimount-Magna valve was chosen. A second stitch was used to close the arteriotomy with large bites in a double row to reduce the perimeter of the trunk. Cardiopulmonary bypass was discontinued (after 64 minutes), and the cannulas were removed sequentially. Echocardiography showed a good result, with proper valve function and a reduced pulmonary artery. The patient was discharged on postoperative day 12 on antiplatelet therapy.

Complications and inappropriate shocks in pediatric patients receiving a subcutaneous implantable cardioverter defibrilator.

INTRODUCTION AND OBJECTIVES: There is limited evidence regarding the use of subcutaneous implantable cardioverter-defibrillators (S-ICD) in pediatric patients. The aim of this study was to determine the incidence of complications in these patients at our center, according to the type of ICD and patient size. METHODS: We included all patients aged<18 years who received an S-ICD since 2016 at our center. As a control group, we also included contemporary patients (since 2014) who received a transvenous ICD (TV-ICD). The primary endpoint was a composite of complications and inappropriate shocks. RESULTS: A total of 26 patients received an S-ICD (median age, 14 [5-17] years; body mass index [BMI], 20.2 kg/m2). Implantation was intermuscular in 23 patients (88%) and subserratus in the remainder. Two incisions were used in 24 patients (92%). In all patients, 2 zones were programmed: a conditional zone set at 230 (220-230) bpm, and a shock zone set at 250 bpm. Nineteen patients received a TV-ICD (median age, 11 [range, 5-16] years; BMI, 19.2 kg/m2, 79% single-chamber). Survival free from the primary endpoint at 5 years was 80% in the S-ICD group and 63% in the TV-ICD group (P=.54). Survival free from inappropriate shocks was similar (85% vs 89%, P=.86), while survival free from complications was higher in the S-ICD group (96% vs 57%, cloglog P=.016). There were no therapy failures in the S-ICD group, and no increased complication rates were observed in patients with BMI ≤20 kg/m2. CONCLUSIONS: With contemporary implantation techniques and programming, S-ICD is a safe and effective therapy in pediatric patients. The number of inappropriate shocks is similar to TV-ICD, with fewer short- and mid-term complications.

A Novel GMP Protocol to Produce High-Quality Treg Cells From the Pediatric Thymic Tissue to Be Employed as Cellular Therapy.

Due to their suppressive capacity, the adoptive transfer of regulatory T cells (Treg) has acquired a growing interest in controlling exacerbated inflammatory responses. Limited Treg recovery and reduced quality remain the main obstacles in most current protocols where differentiated Treg are obtained from adult peripheral blood. An alternate Treg source is umbilical cord blood, a promising source of Treg cells due to the higher frequency of naïve Treg and lower frequency of memory T cells present in the fetus' blood. However, the Treg number isolated from cord blood remains limiting. Human thymuses routinely discarded during pediatric cardiac surgeries to access the retrosternal operative field has been recently proposed as a novel source of Treg for cellular therapy. This strategy overcomes the main limitations of current Treg sources, allowing the obtention of very high numbers of undifferentiated Treg. We have developed a novel good manufacturing practice (GMP) protocol to obtain large Treg amounts, with very high purity and suppressive capacity, from the pediatric thymus (named hereafter thyTreg). The total amount of thyTreg obtained at the end of the procedure, after a short-term culture of 7 days, reach an average of 1,757 x106 (range 50 x 106 - 13,649 x 106) cells from a single thymus. The thyTreg product obtained with our protocol shows very high viability (mean 93.25%; range 83.35% - 97.97%), very high purity (mean 92.89%; range 70.10% - 98.41% of CD25+FOXP3+ cells), stability under proinflammatory conditions and a very high suppressive capacity (inhibiting in more than 75% the proliferation of activated CD4+ and CD8+ T cells in vitro at a thyTreg:responder cells ratio of 1:1). Our thyTreg product has been approved by the Spanish Drug Agency (AEMPS) to be administered as cell therapy. We are recruiting patients in the first-in-human phase I/II clinical trial worldwide that evaluates the safety, feasibility, and efficacy of autologous thyTreg administration in children undergoing heart transplantation (NCT04924491). The high quality and amount of thyTreg and the differential features of the final product obtained with our protocol allow preparing hundreds of doses from a single thymus with improved therapeutic properties, which can be cryopreserved and could open the possibility of an "off-the-shelf" allogeneic use in another individual.

Continuous Incisional Lidocaine in Pediatric Patients following Open Heart Surgery.

Continuous incisional lidocaine infusion has been proposed as an adjunctive therapy in the management of postoperative pain in adult patients. The aim of this study was to determine the efficacy and safety of a continuous subcutaneous lidocaine infusion in pediatric patients following open heart surgery. All patients receiving a subcutaneous lidocaine infusion in median sternotomy incisions after open heart surgery during 2 consecutive years were included in the study. A historical cohort of patients was used as a control group. Demographic variables (age, size, and surgical procedure), variables related to sedation and analgesia (COMFORT and analgesia scales, drug doses, and duration), and complications were registered. 106 patients in the lidocaine infusion group and 79 patients in the control group were included. Incisional analgesia was effective for the treatment of pain as it reduced the dose and duration of intravenous fentanyl (odds ratio (OR) 6.26, confidence interval (CI) 95%: 2.48-15.97, p = 0.001; OR 4.30, CI 95%: 2.09-8.84, p = 0.001, respectively). The reduction in fentanyl use was more important in children over two years of age. Adverse effects were seen in three children (2.8%): they all had decreased level of consciousness, and one of them presented seizures as well. Two of these three patients had lidocaine levels over 2 mcg/ml. A continuous lidocaine incisional infusion is effective for the treatment of pain after open heart surgery. This procedure reduced intravenous analgesic drug requirements in pediatric patients undergoing a median sternotomy incision. Although the incidence of secondary effects is low, monitoring of neurologic status and lidocaine blood levels are recommended in all patients.

A Neonatal ABO non-compatible heart transplant from a circulatory-determined death donor using NRP/Cold storage.

BACKGROUND: Donation after Circulatory death is gaining worldwide acceptance. Most protocols regard their first cases to be performed with donor and recipient in the same institution. Few records of children or distant procurement have been published. METHODS: Our institution was offered a heart from a 3-day-old, 3.4-kg child, blood group A, suffering irreversible encephalopathy. Parents accepted withdrawal of life-sustaining therapy and agreed to donation. The donor hospital was located 340 km away. Concomitantly, a 2-month-old, 3.1 kg, blood group type B and with non-compaction ventricles was awaiting for the heart transplant in our unit. RESULTS: Thirty-seven minutes after withdrawal of life-sustaining therapy, the heart arrested. Five minutes afterwards, a sternotomy was performed. The supra-aortic vessels were clamped altogether. Aorta and right appendage were cannulated and connected to heart-lung machine. The innominate artery above the clamp was severed. The heart resumed spontaneous rhythm in less than 1 min. Ventilation was restored and extracorporeal circulation was maintained for 32 min. Upon cardiologic arrest, the graft was harvested as routinely. The heart was cold-stored and transported by plane to our Hospital. An orthotopic bicaval transplant was performed. Overall cold ischaemia was 245 min. Ten weeks later, the child was discharged home in good condition. CONCLUSION: Donation in circulatory death could increase the pool in neonates. Extracorporeal circulation proves successful for procurement in neonates. Distant procurement plus cold storage for donation in circulatory death is feasible. Donation in circulatory death and ABO non-compatible strategies are complementary to each other.

Hybrid Procedures. Opening Doors for Surgeon and Cardiologist Close Collaboration.

Background: Collaboration between cardiac surgeons and cardiologists can offer interventions that each specialist may not be able to offer on their own. This type of collaboration has been demonstrated with the hybrid Stage I in patients with hypoplastic heart syndrome. Since that time, a hybrid approach to cardiac interventions has been expanded to an incredible variety of potential indications. Methods: Seventy-one patients were scheduled for a hybrid procedure along 8 years. This was defined as close collaboration between surgeon and cardiologist working together in the same room, either cath-lab (27 patients) or theater (44 patients). Results: Six groups were arbitrarily defined. A: vascular cut-down in the cath-lab (27 neonates); B: bilateral banding (plus ductal stent) in hypoplastic left heart syndrome or alike (15 children); C: perventricular closure of muscular ventricular septal defect (10 cases); D: balloon/stenting of pulmonary branches along with major surgical procedure (12 kids); E: surgical implantation of Melody valve (six patients) and others (F, one case). Two complications were recorded: left ventricular free wall puncture and previous conduit tearing. Both drawbacks were successfully sort out under cardiopulmonary by-pass. Conclusion: Surgeon and cardiologist partnership can succeed where their isolated endeavors are not enough. Hybrid procedures keep on spreading, overcoming initial expectations. As a bridge to biventricular repair or transplant, bilateral banding plus ductal stent sounds interesting. Novel indications can be classified into different groups. Hybrid procedures are not complication-free.

Point-of-care manufacturing: a single university hospital's initial experience.

BACKGROUND: The integration of 3D printing technology in hospitals is evolving toward production models such as point-of-care manufacturing. This study aims to present the results of the integration of 3D printing technology in a manufacturing university hospital. METHODS: Observational, descriptive, retrospective, and monocentric study of 907 instances of 3D printing from November 2015 to March 2020. Variables such as product type, utility, time, or manufacturing materials were analyzed. RESULTS: Orthopedic Surgery and Traumatology, Oral and Maxillofacial Surgery, and Gynecology and Obstetrics are the medical specialties that have manufactured the largest number of processes. Working and printing time, as well as the amount of printing material, is different for different types of products and input data. The most common printing material was polylactic acid, although biocompatible resin was introduced to produce surgical guides. In addition, the hospital has worked on the co-design of custom-made implants with manufacturing companies and has also participated in tissue bio-printing projects. CONCLUSIONS: The integration of 3D printing in a university hospital allows identifying the conceptual evolution to "point-of-care manufacturing."

Ectopic FOXP3 Expression in Combination with TGF-ß1 and IL-2 Stimulation Generates Limited Suppressive Function in Human Primary Activated Thymocytes Ex Vivo.

Regulatory T cells (Tregs), which are characterized by the expression of the transcription factor forkhead box P3 (FOXP3), are the main immune cells that induce tolerance and are regulators of immune homeostasis. Natural Treg cells (nTregs), described as CD4+CD25+FOXP3+, are generated in the thymus via activation and cytokine signaling. Transforming growth factor beta type 1 (TGF-ß1) is pivotal to the generation of the nTreg lineage, its maintenance in the thymus, and to generating induced Treg cells (iTregs) in the periphery or in vitro arising from conventional T cells (Tconvs). Here, we tested whether TGF-ß1 treatment, associated with interleukin-2 (IL-2) and CD3/CD28 stimulation, could generate functional Treg-like cells from human thymocytes in vitro, as it does from Tconvs. Additionally, we genetically manipulated the cells for ectopic FOXP3 expression, along with the TGF-ß1 treatment. We demonstrated that TGF-ß1 and ectopic FOXP3, combined with IL-2 and through CD3/CD28 activation, transformed human thymocytes into cells that expressed high levels of Treg-associated markers. However, these cells also presented a lack of homogeneous suppressive function and an unstable proinflammatory cytokine profile. Therefore, thymocyte-derived cells, activated with the same stimuli as Tconvs, were not an appropriate alternative for inducing cells with a Treg-like phenotype and function.

Technical modifications for transplant in the failing Fontan.

INTRODUCTION: Heart transplant after Fontan completion poses a unique surgical challenge. Twenty patients are presented, stressing the technical hints performed in the five anastomoses to match the graft in the recipient. METHODS: Data are collected from 20 Fontan patients between 2013 and 2019. Age (13 years), weight (37 kg.), and time interval between Fontan and transplant (7 years) are presented as median. Extracardiac conduit (size 18/20) was implanted in 15 patients, whereas atrio-pulmonary connection was performed in 4 and lateral tunnel in 1. Six patients developed protein-losing enteropathy. Seventeen stents had been previously deployed. RESULTS: The five anastomoses underwent some changes. Left atrium once, aorta 9 times, superior vena cava 7 times, pulmonary branches 15 times, and inferior vena cava 12 times. Follow-up was complete for a median of 42 months (range 6-84). Two patients died. ECMO was needed in six cases for pulmonary hypertension. Four patients had collateral vessels occluded in the cath lab, and stents were placed in superior vena cava (1) and aorta (1) post-transplant. Protein-losing enteropathy was resolved in five patients. Interestingly, one patient was on a systemic assist device before transplant (Levitronix) and right assistance (ECMO) afterwards. CONCLUSIONS: Transplant in Fontan patients is actually challenging. Hints in every of the five proposed anastomoses must be anticipated, including stents removal. Extra tissue from the donor (innominate vein, aortic arch, and pericardium) is strongly advisable. ECMO for right ventricular dysfunction was needed in nearly one-third of the cases. Overall results can match other transplant cohorts.

First Experience with Fluorescence in Pediatric Laparoscopy.

Background The use of intraoperative fluorescence images with indocyanine green (ICG) has recently been described as an aid in decision-making during surgical procedures in adults. We present our first experiences with different laparoscopic procedures performed in children using ICG fluorescence images. Material and Method We have used ICG fluorescence imaging technique in varicocele ligation, two nephrectomies, cholecystectomy, and one case of aortocoronary fistula closure. All procedures were performed through a minimally invasive approach. A high definition camera equipped with a visible infrared light source and gray-scale vision technology was used. After injection of ICG before or during the laparoscopic procedure, precise identification of vascular anatomy and bile duct architecture were easily identified. Fluorescence helped to assess blood flow from the spermatic vessels, define the variability of renal vascularization, and determine the precise location of the aortocoronary fistula. Biliary excretion of the ICG allowed the definition of the biliary tract. Conclusion Fluorescein-assisted images allowed a clear definition of the anatomy and safe surgical maneuvers during surgical procedures. The ICG imaging system seems to be simple and safe. Larger and more specific studies are needed to confirm its applicability, expand its indications, and address its advantages and disadvantages.

"Double-barrel endocarditis".

We report a case of an 18-year-old woman who presented with infective endocarditis (IE), in two conduits percutaneously delivered in the right ventricle outflow tract ("double-barrel endocarditis"). The patient's clinical presentation, echocardiogram findings, infectious agent, clinical management, surgical approach, and follow-up assessment are described. Percutaneous pulmonary valve implantation has emerged as a viable therapy for conduit dysfunction in the right ventricular outflow tract. Although the percutaneous approach has several advantages, this strategy and the valves used are not complication-free. IE after transcatheter valve deployment has evoked the growing concern, as there is a higher incidence in these patients compared with patients with surgically repaired pulmonary valves. As a result, this type of surgical treatment is especially important.

Upper Ministernotomy for Pulmonary Valve Repair.

Pulmonary valve repair in an adolescent through upper ministernotomy is reported. Several tips to enhance proper display of the valve in the surgical field are depicted.

Paracorporeal Connection to Heart-Lung Machine in Transplant Surgery With the Berlin Heart Ventricular Assist Device.

This report describes a simple way to deal with time-consuming adhesions and cannula handling in patients with a paracorporeal assist device who are undergoing heart transplantation. By connecting the extrathoracic lines to the heart-lung machine, chest reentry becomes a straightforward issue.

Beating-heart aortic arch surgery in neonates and infants.

OBJECTIVES: Aortic arch repair has been shifted from deep hypothermia plus circulatory arrest to cerebral perfusion at tepid temperatures. A step forward is a simultaneous brain-coronary perfusion, allowing beating-heart arch surgery. METHODS: A 'Y' cannula from the arterial line delivers oxygenated blood to brain and heart. The arch is repaired on a beating heart at 25°C. Intracardiac repair is performed after running cardioplegia through the root line. Fifty patients are classified into 3 groups: A, Norwood (8 neonates); B, aortic arch (14 children) and C, aortic arch plus intracardiac repair (28 patients). Associated anomalies in Group C are as follows: ventricular septal defect (10), arterial switch (5), atrial septal defect (4), cor triatriatum (3), aortic commissurotomy (2), comprehensive repair (2), ostium primum (1) and Yasui (1). RESULTS: The mean bypass time was 161 ± 54.44 (range 93-312) min. Mean brain-coronary perfusion was 37.26 ± 10.54 (18-60) min. Mean coronary ischaemia was 31 ± 32.40 (0-160) min. The heart was not arrested in Group B patients. Follow-up was complete for a mean of 30 (1-48) months. Four patients died in the postoperative period. Two required angioplasty for recoarctation. CONCLUSIONS: Selective brain-coronary perfusion is feasible and easy to switch to conventional cardioplegia delivery. Coronary ischaemia can be notably reduced and even 0 min in isolated arch surgery.

How to set-up a program of minimally-invasive surgery for congenital heart defects.

BACKGROUND: Mid-line sternotomy is the commonest incision for cardiac surgery. Alternative approaches are becoming fashionable in many centres, amidst some reluctance because of learning curves and overall complexity. Our recent experience in starting a new program on minimally invasive pediatric cardiac surgery is presented. The rationale for a stepwise onset and the short-medium term results for a three-year span are displayed. METHODS: A three-step schedule is planned: First, an experienced surgeon (A) starts performing simple cases. Second, new surgeons (B, C, D, E) are introduced to the minimally invasive techniques according to their own proficiency and skills. Third, the new adopters are enhanced to suggest and develop further minimally invasive approaches. Two quality markers are defined: conversion rate and complications. RESULTS: In part one, surgeon A performs sub-mammary, axillary and lower mini-sternotomy approaches for simple cardiac defects. In part two, surgeons B, C, D and E are customly introduced to such incisions. In part three, new approaches such as upper mini-sternotomy, postero-lateral thoracotomy and video-assisted mini-thoracotomy are introduced after being suggested and developed by surgeons B, C and E, as well as an algorithm to match cardiac conditions and age/weight to a given alternative approach. The conversion rate is one out of 148 patients. Two major complications were recorded, none of them related to our alternative approach. Four minor complications linked to the new incision were registered. The minimally invasive to mid-line sternotomy ratio rose from 20% in the first year to 40% in the third year. CONCLUSIONS: Minimally invasive pediatric cardiac surgery is becoming a common procedure worldwide. Our schedule to set up a program proves beneficial. The three-step approach has been successful in our experience, allowing a tailored training for every new surgeon and enhancing the enthusiasm in developing further strategies on their own. Recording conversion-rates and complications stands for quality standards. A twofold increase in minimally invasive procedures was observed in two years. The short-medium term results after three years are excellent.