Cased-based education rounds-the eternal heart of an international training program.

Case-based teaching or "Morning Rounds" have been used in medical education for more than a century and remain a cornerstone for teaching in many training programs. Our Pediatric Critical Care Medicine (PCCM) program was established forty years ago and has retained this form of teaching since its inception. Case-based rounds have consistently had the highest evaluation of all curricula in our program. Here we review the history of how these rounds were introduced in medical education, provide data from the learners' evaluation of these case-based rounds, and discuss the strengths and potential drawbacks of this form of teaching from an educational theories perspective with the hope that they can be used by other Pediatric Critical Care training programs.

The use of milrinone in neonates with persistent pulmonary hypertension of the newborn - a randomised controlled trial pilot study (MINT 1).

OBJECTIVE: To assess the impact of milrinone administration on time spent on nitric oxide (iNO) in infants with acute pulmonary hypertension (aPH). We hypothesized that intravenous milrinone used in conjunction with iNO would reduce the time on iNO therapy and the time spent on invasive ventilation in infants ≥34 weeks gestation with a diagnosis of aPH. We aimed to assess the practicality of instituting the protocol and contributing to a sample size calculation for a definitive multicentre study. STUDY DESIGN: This was a multicentre, randomized, double-blind, two arm pilot study, with a balanced (1:1) allocation. Infants with a gestation ≥34 weeks and a birth weight ≥2000 grams aPH, an oxygenation index of ≥10, and commenced on iNO were eligible. Participants on iNO were assigned to either a milrinone infusion (intervention) or a normal saline infusion (placebo) for up to 35 h. The primary outcome was time on iNO and feasibility of conducting the protocol. RESULTS: The trial was terminated early after 4 years of enrollment due to poor recruitment. Four infants were allocated to the intervention arm and 5 to the placebo arm. The groups were well matched for baseline variables. No differences were seen in any of the primary or secondary outcomes. CONCLUSION: Conducting an interventional trial in the setting of acute pulmonary hypertension in infants is not feasible using our current approach. Future studies in this area require alternative trial design to improve recruitment as this topic remains understudied in the neonatal field. TRIAL REGISTRATION: www.isrctn.com ; ISRCTN:12949496; EudraCT Number:2014-002988-16.

Serial Assessment of Cardiac Function and Pulmonary Hemodynamics in Infants With Down Syndrome.

BACKGROUND: There is a dearth of longitudinal data describing the evolution of cardiopulmonary hemodynamics in infants with Down syndrome (DS) beyond infancy. We hypothesized that babies with DS, independent of the presence of congenital heart disease (CHD), demonstrate biventricular systolic and diastolic impairment and sustained elevation of pulmonary pressures compared with controls over the first 2 years of age. METHODS: This was a prospective observational cohort study of 70 infants with DS (48 with CHD and 22 without CHD) and 60 controls carried out in 3 tertiary neonatal intensive care units in Dublin, Ireland. Infants with DS with and without CHD and non-DS controls underwent serial echocardiograms at birth, 6 months, 1 year, and 2 years of age to assess biventricular systolic and diastolic function using deformation analysis. Pulmonary vascular resistance was assessed using pulmonary artery acceleration time and left ventricular (LV) eccentricity index. RESULTS: Infants with DS exhibited smaller LV (birth: 27 ± 4 vs 31 ± 2 mm, P < .01; 2 years: 43 ± 5 vs 48 ± 4 mm, P < .01) and right ventricular (birth: 28 ± 3 vs 31 ± 2 mm, P < .01; 2 years: 40 ± 4 vs 44 ± 3 mm, P < .01) lengths and lower LV (birth: -19% ± 3% vs -22% ± 2%, P < .01; 2 years: -24% ± 2% vs -26% ± 2%, P < .01) and right ventricular (birth: -19% ± 4% vs -22% ± 3%, P < .01; 2 years: -29% ± 6% vs -33% ± 4%, P < .01) systolic strain over the 2-year period. Pulmonary artery acceleration time was lower in the DS group throughout the study period (birth: 44 ± 10 vs 62 ± 14 ms, P < .01; 2 years 71 ± 12 vs 83 ± 11 ms, P < .01). No differences were observed between DS infants with and without CHD (all P > .05). CONCLUSIONS: Infants with DS exhibit impaired maturational changes in myocardial function and pulmonary vascular resistance. Such novel findings provide valuable insights into the pathophysiology affecting cardiorespiratory morbidity in this population.

Short- and medium-term outcomes for patent ductus arteriosus stenting in neonates ≤2.5 kg with duct-dependent pulmonary circulation.

BACKGROUND: Morbidity with surgical systemic-to-pulmonary artery shunting (SPS) in infants ≤2.5 kg has remained high. Patent ductus arteriosus (PDA) stenting may be a valid alternative. The objective of this study is to evaluate outcomes following PDA stenting in patients ≤2.5 kg from four large tertiary centers. METHODS: Retrospective review of all neonates ≤2.5 kg with duct-dependent pulmonary circulation who underwent PDA stenting. Procedural details, pulmonary arterial growth, reinterventions, surgery type, and outcomes were assessed. RESULTS: PDA stents were implanted in 37 of 38 patients attempted (18 female) at a median procedural weight of 2.2 kg (interquartile range [IQR], 2-2.4 kg). Seven patients (18%) had a genetic abnormality and 16 (42%) had associated comorbidities. The median intensive care unit stay was 4 days (IQR, 2-6.75 days), and the median hospital stay was 20 days (IQR, 16-57.25). One patient required a rescue shunt procedure, with three others requiring early SPS (<30 days postprocedure). Twenty patients (54%) required reintervention with either balloon angioplasty, restenting, or both. At 6-month follow-up, right pulmonary artery growth (median z-score -1.16 to 0.01, p = 0.05) was greater than the left pulmonary artery (median z-score -0.9 to -0.64, p = 0.35). Serious adverse effects (SAEs) were seen in 18% (N = 7) of our cohort. One patient developed an SAE during planned reintervention There were no intraprocedural deaths, with one early procedure-related mortality, and three interstage mortalities not directly related to PDA stenting. CONCLUSIONS: PDA stenting in infants ≤2.5 kg is feasible and effective, promoting pulmonary artery growth. Reintervention rates are relatively high, though many are planned to allow for optimal growth before a definitive operation.

Relationship Between Postnatal Pulmonary Arterial Pressure and Altered Diastolic Function in Neonates with Down Syndrome.

OBJECTIVE: To assess the influence of diastolic dysfunction on the evolution of pulmonary hypertension in neonates with Down Syndrome over the early newborn period. STUDY DESIGN: This was a prospective observational cohort study. Echocardiography was performed three times over the first week of life in both Down syndrome and control cohorts. Measurements of pulmonary arterial pressure in addition to left ventricular (LV) and right ventricular systolic and diastolic function were collected. RESULTS: Seventy babies with Down syndrome and 60 control infants were enrolled. Forty-eight of the infants with Down syndrome (69%) were born with congenital heart disease (CHD). Echocardiography surrogates of pulmonary hypertension and myocardial function remained significantly impaired in the Down syndrome group in comparison with control infants (all P < .01). In the Down syndrome group, LV early diastolic strain rate was independently associated with measures of pulmonary hypertension while controlling for gestational age, cesarean delivery, and the presence of CHD (P < .01). CONCLUSIONS: Intrinsic LV diastolic impairment is directly associated with higher indices of pulmonary hypertension in infants with Down syndrome and may be a contributing factor to its evolution.

Peri-operative myocardial performance in infants with Down syndrome undergoing CHD repair.

BACKGROUND: We aimed to characterise the impact of Down syndrome on myocardial performance and loading conditions in infants with Down syndrome and CHD over the peri-operative period by comparing them with infants matched for cardiac lesion with a normal microarray. METHODS: Left ventricular global longitudinal strain, right ventricular free wall longitudinal strain, left ventricular end-systolic wall stress, and right ventricular systolic pressure were measured in the two groups over the peri-operative period. RESULTS: Fifty-five infants had a diagnosis of Down syndrome and these were compared with 29 control infants. Left ventricular global longitudinal strain decreased in both groups post-operatively with the Down syndrome group demonstrating some recovery pre-discharge (18 ± 3 versus 16 ± 3 %, p = 0.01). Right ventricular longitudinal strain significantly decreased in both groups post-operatively with the control group demonstrating better recovery by hospital discharge (14 ± 4 versus 18 ± 6 %, p < 0.01). End-systolic wall stress was lower and right ventricular systolic pressure was higher in the Down syndrome group throughout the study period (all p < 0.05). Down syndrome was an independent predictor of the duration of ventilation, post-operative use of inotropes, and intensive care stay. Right ventricular longitudinal strain was an independent predictor of duration of intensive care stay. CONCLUSION: This study demonstrates the difference between the two groups in relation to left and right ventricular function, particularly prior to discharge, and outlines the additional impact a diagnosis of Down syndrome has on myocardial performance during the peri-operative period.

Transcarotid Approach to Ventricular Septal Defect Closure in Small Infants.

Perimembranous ventricular septal defect closure in small infants has traditionally been a surgically treated defect, although alternative hybrid strategies are emerging. We aim to describe a novel approach to retrograde device closure of clinically relevant perimembranous ventricular septal defects in small infants via carotid cutdown. A retrospective review of all patients managed with attempted carotid cutdown for device closure of a perimembranous ventricular septal defect was recorded at a single tertiary cardiac centre. We summarized data on successful device deployment, conversion to open repair, complications, and length of stay. Eighteen infants with median (IQR) age of 7 months (5-9 months) and weight of 7.1 kg (6.5-7.8 kg) with clinically relevant PMVSD underwent attempted retrograde closure via carotid cutdown. Median (IQR) defect size was 8 mm (7-9 mm). Successful device deployment without significant aortic or tricuspid valve interference occurred in 15 (83%) patients. Three patients were converted to open repair, one following damage to the tricuspid valve apparatus. Median (IQR) hospital stay was 1 day (1-3 days). There were no complications related to carotid cutdown. Retrograde device closure of hemodynamically significant PMVSD is feasible and effective in small infants. Decision to convert to surgical repair should be made early if suboptimal device placement occurs. Carotid evaluation should be performed to rule out any access-related complications.

Patent ductus arteriosus shunt elimination results in a reduction in adverse outcomes: a post hoc analysis of the PDA RCT cohort.

OBJECTIVE: A post hoc appraisal of the PDA RCT to assess the relationship between early patent ductus arteriosus (PDA) shunt elimination and chronic lung disease or death (CLD/Death). STUDY DESIGN: Infants <29 weeks were divided into four groups: intervention arm in whom PDA closure was achieved (n = 17); intervention arm in whom PDA closure was not achieved (n = 13); placebo arm (n = 30); low risk infants (n = 13). The main outcome measure was CLD/Death. RESULTS: The rates of CLD/Death were lower in the Intervention Success Group (29%) when compared to the Intervention Failure Group (85%) or the Placebo Group (60%, all p < 0.05). There was no difference in CLD/Death between the Intervention Success and Low Risk Groups (8%, p > 0.05). A persistent PDA beyond Day 8 was associated with CLD/Death (aOR 6.5 [1.7-25.5]). CONCLUSIONS: Early shunt elimination in preterm infants with a PDA may reduce respiratory morbidity when compared to infants with prolonged shunt exposure.

Hybrid Subxiphoid Perventricular Approach as an Alternative Access in Neonates and Small Children Undergoing Complex Congenital Heart Interventions.

The hybrid subxiphoid perventricular approach provides direct access through the heart and may alleviate the technical limitations of complex percutaneous interventions particularly in infants with low body weight. We present the outcomes from a tertiary cardiology center using this approach. We performed a retrospective review of all patients less than 15 kg who underwent a hybrid perventricular approach via a small subxiphoid incision. Medical records were reviewed to obtain clinical, demographic and outcome data. Seventeen patients underwent 18 hybrid perventricular procedures using a subxiphoid approach. Median age at time of procedure was 4.6 months (IQR = 1.6 to 18 months) and median weight was 6.2 kgs (IQR = 3.4 to 8.6 kgs). Six patients underwent hybrid pulmonary valve replacement (PVR), 5 patients underwent pulmonary outflow stenting, and 5 infants underwent hybrid ventricular septal defect (VSD) device closure. One patient with a single ventricle who did not tolerate a percutaneous approach underwent left pulmonary artery (LPA) stenting for severe LPA coarctation with subsequent right ventricular outflow tract (RVOT) stenting. One further patient underwent implantation of a larger diameter stent for pulmonary artery bifurcation stenosis. Procedure success rate was 89% with two of the VSD cases reverted to open surgical repair. There were no intra-procedural complications; however, one patient died within 72 h. Minor adverse events occurred in 2 patients including a wound infection in one patient with an immunodeficiency syndrome. Hybrid subxiphoid perventricular approach provides an excellent alternative access to the heart especially in low birth weight infants to prevent hemodynamic instability or in small children requiring large delivery sheaths.

Procedural technique for hybrid pulmonary valve replacement in infants and small children.

OBJECTIVES: Hybrid approach to pulmonary valve replacement (PVR) in the paediatric population has been reported, although data in infants and small children are limited. Several strategies are now possible. The aim of this study is to review our hybrid PVR strategy in a complex patient cohort, outlining a variety of approaches employed in our centre. METHODS: We performed a retrospective review of infants and small children who underwent hybrid PVR between May 2017 and April 2019 in a single tertiary cardiology centre. Medical records were reviewed to ascertain demographic, clinical and outcome data. RESULTS: Ten patients with a median (interquartile range) age of 1.5 years (1.1-1.9) and weight of 8.8 kg (8-10.6) were managed with hybrid pulmonary valve insertion. Eight patients had perventricular approach (4 sternotomy and 4 subxiphoid) and 2 patients had surgically sutured valve. Six patients underwent cardiopulmonary bypass for associated lesions. Three had insertion of the valve into conduits and 7 were deployed into native right ventricular outflow tracts. The pulmonary valve was successfully inserted in all 10 patients with no mortality. Postprocedural complications included paravalvar leak in 2 patients, suspected endocarditis in 1 patient who developed early valve regurgitation and wound infection in 1 patient. CONCLUSIONS: Several approaches to hybrid PVR may be employed in small children with a high success rate. Follow-up studies are required to evaluate longer term durability of these approaches compared to standard surgical replacement.

A Pilot Randomized Controlled Trial of Early Targeted Patent Ductus Arteriosus Treatment Using a Risk Based Severity Score (The PDA RCT).

OBJECTIVES: To evaluate the feasibility of recruiting preterm infants to a randomized controlled trial of patent ductus arteriosus (PDA) treatment based on a PDA severity score (PDAsc) and to characterize challenges in obtaining consent, compliance with the protocol, and PDA closure rates. STUDY DESIGN: This single-center, randomized control pilot study of 60 infants <29 weeks of gestation with a high PDAsc (≥5.0) at 36-48 hours of age receiving either ibuprofen or placebo intravenously. The study protocol did not allow for additional PDA therapy within the first 2 weeks. We reported the rate of consent, open label treatment, and PDA closure rates. The primary outcome was chronic lung disease or death. RESULTS: We approached 83 families for enrollment with 73 (88%) providing consent; 13 infants had a PDAsc of <5; of the remaining infants, 30 were assigned ibuprofen and 30 received placebo. Eight infants received open label treatment in the first 2 weeks (12%). The overall PDA closure rate after treatment was 57% in the intervention group and 17% in the control group (P < .01). There was no difference in the primary clinical outcome (OR, 0.8; 95% CI, 0.3-2.1). CONCLUSIONS: Using a PDAsc for infant recruitment to a PDA treatment randomized controlled trial is feasible. There is a high rate of consent and relatively low rate of open-label PDA treatment. The overall PDA closure rate in the intervention arm was low placing the emphasis on devising more effective PDA closure strategies in future randomized controlled trials. TRIAL REGISTRATION: ISRCTN (13281214) and European Union Drug Regulating Authorities Clinical Trials Database (2015-004526-33).

Prenatal prediction of neonatal haemodynamic adaptation after maternal hyperoxygenation.

The reactivity of the pulmonary vascular bed to the administration of oxygen is well established in the post-natal circulation. The vasoreactivity demonstrated by the fetal pulmonary artery Doppler waveform in response to maternal hyperoxia has been investigated. We sought to investigate the relationship between the reactivity of the fetal pulmonary arteries to hyperoxia and subsequent neonatal cardiac function in the early newborn period. METHODS: This explorative study with convenience sampling measured pulsatility index (PI), resistance index (RI), acceleration time (AT), and ejection time (ET) from the fetal distal branch pulmonary artery (PA) at baseline and following maternal hyperoxygenation (MH). Oxygen was administered for 10 min at a rate of 12 L/min via a partial non-rebreather mask. A neonatal functional echocardiogram was performed within the first 24 h of life to assess ejection fraction (EF), left ventricular output (LVO), and neonatal pulmonary artery AT (nPAAT). This study was conducted in the Rotunda Hospital, Dublin, Ireland. RESULTS: Forty-six women with a singleton pregnancy greater than or equal to 31 weeks' gestational age were prospectively recruited to the study. The median gestational age was 35 weeks. There was a decrease in fetal PAPI and PARI following MH and an increase in fetal PAAT, leading to an increase in PA AT:ET. Fetuses that responded to hyperoxygenation were more likely to have a higher LVO (135 ± 25 mL/kg/min vs 111 ± 21 mL/kg/min, p < 0.01) and EF (54 ± 9% vs 47 ± 7%,p = 0.03) in the early newborn period than those that did not respond to MH prenatally. These findings were not dependent on left ventricular size or mitral valve (MV) annular diameter but were related to an increased MV inflow. There was no difference in nPAAT. CONCLUSION: These findings indicate a reduction in fetal pulmonary vascular resistance (PVR) and an increase in pulmonary blood flow and left atrial return following MH. The fetal response to hyperoxia reflected an optimal adaptation to postnatal life with rapid reduction in PVR increasing measured cardiac output.

Cardiac strangulation causing refractory cardiac arrest during elective pacemaker revision: a cautionary tale.

We describe a previously asymptomatic 7-year-old girl with a sudden cardiac arrest during elective pacemaker revision. Later imaging identified epicardial pacemaker lead strangulation of the left anterior descending and left circumflex coronary arteries. Anaesthetic induction led to a reduction in myocardial perfusion, precipitating the arrest. Extreme care should be taken during anaesthesia if cardiac strangulation is suspected.

Early targeted patent ductus arteriosus treatment in premature neonates using a risk based severity score: study protocol for a randomised controlled trial (PDA RCT).

A patent ductus arteriosus (PDA) in preterm infants is associated with increased ventilator dependence and chronic lung disease, necrotizing enterocolitis, intraventricular haemorrhage, and poor neurodevelopmental outcome. Randomised controlled trials of early PDA treatment have not established a drop in the aforementioned morbidities. Those trials did not physiologically categorise PDA severity. Incorporating the specific physiological features of a haemodynamic significant PDA may evolve our understanding of this phenomenon, allowing accurate triaging using echocardiography and targeted treatment.  Our group has recently demonstrated that a PDA severity score (PDAsc) derived at 36-48 hours of age can accurately predict the later occurrence of chronic lung disease or death (CLD/Death). Using echocardiography, we assessed PDA characteristics, as well as left ventricular diastolic function and markers of pulmonary overcirculation, and from this formulated a PDAsc. Gestation was also incorporated into the score. We hypothesise that in preterm infants at high risk of developing CLD/Death based on a PDAsc, early treatment with Ibuprofen compared with placebo will result in a reduction in CLD/Death. This is a single centre double-blind two arm randomised controlled trial conducted in the neonatal intensive care unit in the Rotunda Hospital, Dublin. Echocardiogram is carried out in the first 36-48 hours of life to identify preterm infants with a PDAsc ≥ 5.0 and these infants are randomised to Ibuprofen or placebo. Primary outcomes are assessed at 36 weeks post menstrual age. This pilot study's purpose is to assess the feasibility of performing the trial and to obtain preliminary data to calculate a sample size for a definitive multi-centre trial of early PDA treatment using a PDAsc. We aim to recruit a total of 60 infants with a high risk PDA over three years. Trial Registration: ISRCTN ISRCTN13281214 (26/07/2016) and the European Union Drug Regulating Authorities Clinical Trials Database 2015-004526-33 (03/12/2015).

Echocardiographic Assessment of Right Ventricular Afterload in Preterm Infants: Maturational Patterns of Pulmonary Artery Acceleration Time Over the First Year of Age and Implications for Pulmonary Hypertension.

BACKGROUND: Assessment of pulmonary hemodynamics is critical in the diagnosis and management of cardiopulmonary disease of premature infants, but reliable noninvasive indices of pulmonary hemodynamics in preterm infants are lacking. Because pulmonary artery acceleration time (PAAT) is a validated noninvasive method to assess right ventricular (RV) afterload in infants and children, the aim of this study was to investigate the maturational changes of PAAT measures in preterm infants over the first year of age and to discern the impact of typical cardiopulmonary abnormalities on these measures. METHODS: In a prospective multicenter study of 239 preterm infants (<29 weeks at birth), PAAT was assessed at days 1, 2, and 5 to 7, at 32 and 36 weeks' postmenstrual age, and at 1-year corrected age. To account for heart rate variability, PAAT was adjusted for RV ejection time. Premature infants who developed bronchopulmonary dysplasia or had echocardiographic findings of pulmonary hypertension were analyzed separately. Intra- and interobserver reproducibility analysis was performed. RESULTS: PAAT was feasible in 95% of the image acquisitions, and there was high intra- and interobserver agreement (intraclass correlation coefficients > 0.9 and coefficients of variation < 6%). In uncomplicated preterm infants (n = 103 [48%]) PAAT and PAAT adjusted for RV ejection time increased longitudinally from birth to 1-year corrected age (P < .001) and were linearly associated with gestational age at birth (r = 0.81 and r = 0.82, P < .001) and increasing postnatal weight and postnatal age (r > 0.81, P < .001). PAAT measures were significantly reduced (P < .001) in infants with bronchopulmonary dysplasia and/or pulmonary hypertension (n = 119 [51%]) beyond 1 week of age. CONCLUSIONS: PAAT measures increase in preterm infants from birth to 1-year corrected age, reflective of the physiologic postnatal drop in RV afterload. Bronchopulmonary dysplasia and pulmonary hypertension have a negative impact on PAAT measures. By demonstrating excellent reliability and establishing reference patterns of PAAT in preterm infants, this study suggests that PAAT and PAAT adjusted for RV ejection time can be used as complementary parameters to assess physiologic and pathologic changes in pulmonary hemodynamics in neonates.

Retroaortic innominate vein in a patient with transposition of the great arteries: the surgical implications.

We describe the case of a newborn infant with transposition of the great vessels and a retroaortic innominate vein. This is a previously undescribed association. The decision was made to incorporate the retroaortic innominate vein into the Lecompte procedure at the time of surgery to avoid the risk of superior caval vein syndrome.

Impaired Right Ventricular Performance Is Associated with Adverse Outcome after Hypoxic Ischemic Encephalopathy.

Rationale: Asphyxiated neonates with hypoxic ischemic encephalopathy (HIE) are at risk of myocardial dysfunction; however, echocardiography studies are limited and little is known about the relationship between hemodynamics and brain injury.Objectives: To analyze the association between severity of myocardial dysfunction and adverse outcome as defined by the composite of death and/or abnormal magnetic resonance imaging.Methods: Neonates with HIE undergoing therapeutic hypothermia were enrolled. Participants underwent echocardiography at 24 hours, 72 hours (before rewarming), and 96 hours (after rewarming). Cerebral hemodynamics were monitored by near-infrared spectroscopy and middle cerebral artery Doppler.Measurements and Main Results: Fifty-three patients with a mean gestation and birthweight of 38.8 ± 2.0 weeks and 3.33 ± 0.6 kg, respectively, were recruited. Thirteen patients (25%) had mild encephalopathy, 27 (50%) had moderate encephalopathy, and 13 (25%) had severe encephalopathy. Eighteen patients (34%) had an adverse outcome. Severity of cardiovascular illness (P < 0.001) and severity of neurologic insult (P = 0.02) were higher in neonates with adverse outcome. Right ventricle (RV) systolic performance at 24 hours was substantially lower than published normative data in all groups. At 24 hours, lower tricuspid annular plane systolic excursion (P = 0.004) and RV fractional area change (P < 0.001), but not pulmonary hypertension, were independently associated with adverse outcome on logistic regression. High brain regional oxygen saturation (P = 0.007) and low middle cerebral artery resistive index (P = 0.04) were associated with RV dysfunction on post hoc analysis.Conclusions: RV dysfunction is associated with the risk of adverse outcome in asphyxiated patients with HIE undergoing hypothermia. Echocardiography may be a valuable diagnostic and prognostic tool in this vulnerable population.

Percutaneous axillary artery approach for ductal stenting in critical right ventricular outflow tract lesions in the neonatal period.

OBJECTIVES: We aimed to assess the experience using a percutaneous axillary artery approach for insertion of arterial ductal stents in patients with critical right ventricular outflow tract lesions at two tertiary pediatric cardiology centers. BACKGROUND: Patent ductus arteriosus stenting is an accepted palliative alternative to BT shunts for neonates with critical right heart lesions. Access to tortuous ductus' may be challenging via the femoral artery, whereas the carotid artery presents a low risk of stroke. Recently, the axillary artery has been utilized for access in these patients. METHODS: We performed a retrospective review of neonates who underwent stent placement or angioplasty using percutaneous axillary artery approach at two tertiary care centers from October 2016 to November 2018. Medical records were reviewed to ascertain demographic, clinical, and outcome data. RESULTS: Axillary artery access was performed in 20 patients (16 primary ductal stents and 4 re-interventions) at a median (IQR) procedural weight of 3.4 (3-3.9) kg. Median (IQR) procedural time was 110 (75-150) min. The median (IQR) ICU stay and intubation times were 14 (0-94) hr and 5 (0-40) hr, respectively. There were three access-related vascular complications which were managed conservatively with no long-term effects. Two patients subsequently died due to non-procedure related causes. CONCLUSIONS: Ductal stenting via a percutaneous axillary artery approach is a viable option in neonates with critical right ventricular outflow tract lesions. This approach provides an additional access site for PDA stenting which may be utilized in patients with vertical duct morphology.

Postnatal Myocardial Function in Monochorionic Diamniotic Twins with Twin-to-Twin Transfusion Syndrome following Selective Laser Photocoagulation of the Communicating Placental Vessels.

BACKGROUND: Monochorionic diamniotic (MCDA) twins are at risk for developing twin-to-twin transfusion syndrome (TTTS) throughout pregnancy. This may lead to myocardial dysfunction in the recipient and/or donor twin that persists beyond delivery. Selective laser photocoagulation of the communicating placental vessels (SLPCV) attempts to mitigate the cardiovascular outcomes. The objective of this study was to characterize early postnatal myocardial performance in MCDA twins with TTTS with and without SLPCV. METHODS: A prospective study was performed of four MCDA twin groups: (1) uncomplicated MCDA twins, (2) MCDA twins with selective fetal growth restriction, (3) MCDA twins with TTTS following SLPCV (TTTS with SLPCV), and (4) MCDA twins with TTTS who did not undergo SLPCV (TTTS without SLPCV). Fifty-four twin pairs were enrolled: 23 uncomplicated MCDA twin pairs, 15 pairs with selective fetal growth restriction, seven TTTS pairs with SLPCV, and seven TTTS pairs without SLPCV. In each group, twin pairs were divided by birth weight into donor (smaller) and recipient (larger) and compared. Echocardiography was performed on day 1, day 2, and between days 5 and 7 of age, and myocardial performance was characterized by speckle-tracking echocardiography-derived left ventricular and right ventricular longitudinal strain (LS) and systolic strain rate (LSR). Longitudinal strain and longitudinal systolic strain rate are expressed as absolute values. RESULTS: Compared with all recipient groups, recipient TTTS without SLPCV infants had lower left ventricular LS (16 ± 3% vs 22%-24%, P < .01) and right ventricular LS (15 ± 5% vs 21%-24%, P < .01) on day 1 that persisted throughout the first week of age. Left ventricular LSR (1.7 ± 0.3 vs 2.3 ± 0.3 sec-1, P < .05) and right ventricular LSR (1.5 ± 0.4 vs 1.7 ± 0.5 sec-1, P < .05) were both lower in the recipient compared with the donor twin in the TTTS without SLPCV group. LS and LSR measurements were similar among all four donor twin groups. CONCLUSIONS: Biventricular performance is diminished in recipient MCDA twins with TTTS who are not treated with SLPCV, highlighting the need for close monitoring of their hemodynamic status during the early neonatal period.