Motor outcome, executive functioning, and health-related quality of life of children, adolescents, and young adults after ventricular assist device and heart transplantation.

OBJECTIVE: The aim of the current study is to measure long-term executive function, motor outcome, and QoL in children, adolescents, and young adults after VAD and Htx. METHODS: Patients were examined during routine follow-up. Investigation tools were used as follows: Examination for MND of motor outcomes, Epitrack® for attention and executive functioning, and Kidscreen-52 and EQ-5D-5L questionnaires for QoL. Additional data were retrospectively obtained by an analysis of patient medical records. RESULTS: Out of 145 heart transplant recipients at the department of pediatric cardiology of the University Hospital Munich, 39 were implanted with a VAD between 1992 and 2016. Seventeen (43.6%) patients died before or after Htx; 22 (56.4%) patients were included in our study. Mean age at transplant was 9.52 years (range: 0.58-24.39 years, median 9), and the mean follow-up time after Htx was 6.18 years (range: 0.05-14.60 years, median 5.82). MND examination could be performed in 13 patients (normal MND: n = 11, simple MND: n = 1, complex MND: n = 1). Executive functioning was tested in 15 patients. Two (13.3%) patients had good results, six (40%) average results, three (20%) borderline results, and four (26.7%) impaired results. QoL (Kidscreen n = 7, EQ-5D-5L n = 8) was similar to a healthy German population. CONCLUSION: Motor outcome, executive functioning and QoL in survivors of VAD bridging therapy and Htx can be good, though underlying diseases and therapies are associated with a high risk of cerebral ischemic or hemorrhagic complications.

The Creation of an Interatrial Right-To-Left Shunt in Patients with Severe, Irreversible Pulmonary Hypertension: Rationale, Devices, Outcomes.

PURPOSE OF THE REVIEW: Targeted pharmacotherapies did improve survival rates, exercise capacity, and quality of life (QoL) of PAH patients. However, these pharmacological interventions are expensive and not always accessible. In addition, not all patients do respond similarly to these medications and many will continue to deteriorate. This review aims to discuss the beneficial role of an artificial right-to-left shunt and highlights current interventional devices and outcomes. RECENT FINDINGS: Since patients with preexisting atrial shunts or patients with Eisenmenger's disease show better survival rates, improved exercise capacity, and QoL, PAH patients clinically do benefit from an atrial septostomy by reducing signs of right heart failure, improving left heart filling, cardiac output, and systemic oxygen transport despite hypoxia. However, an uncontrolled septostomy with unrestricted right-to-left shunt bears the risk of acute severe desaturation and death. The Atrial Flow Regulator (AFR device, Occlutech®, Sweden) provides an adjustable shunt size with restricted flow and excellent short-term outcomes. Interventional strategies for PAH palliation are on the rise. The novel AFR device provides a durable and safe option for a controlled right-to-left shunting, thus enabling an individualized management.

Creation of a defined and stable Fontan fenestration with the new Occlutech Atrial Flow Regulator (AFR®).

This report describes the first clinical experience with the new Occlutech Atrial Flow Regulator (AFR®) device for implementation of a late Fontan fenestration. The AFR® device secured a defined diameter of the fenestration without spontaneous re-occlusion of this extra-anatomic perforation. This ensured a permanent clinical improvement of our failing Fontan patient.

Closure of very large PDA with pulmonary hypertension: Initial clinical case-series with the new Occlutech® PDA occluder.

OBJECTIVE: We report our recent experience with the new Occlutech® PDA Occluder, which seems suitable especially for closure of large patent ductus arteriosus (PDA) sizes with elevated pulmonary artery pressure (PAH). BACKGROUND: Although considered a standard procedure in pediatric cath labs, closure of very large PDA (PDA/Aorta ratio > 0.5) and PAH remains a challenge. METHODS/RESULTS: The Occlutech® PDA occluder was used in eight children and adolescents (age 4-16, median 10.75 years), body weight from 14 to 54 kg (median 21 kg) with very large PDA and PAH: PDA diameter was 5-13 mm (median 10 mm); PAP/Aortic pressure ratio was 0.58-0.96. Sufficient occlusion of the PDA was documented by angiography and/or echocardiography in all cases. Four different device sizes were selected: Minimal diameter 6-14 mm (median 12 mm), length 6.3-16 mm (median 14 mm), aortic disc 13-24 mm (median 20 mm), size at the pulmonary end 8-18 mm (median 15 mm). A balloon test occlusion of the PDA was performed in five patients in order to evaulate the decline of pulmonary artery pressure or to delineate the exact anatomy of the PDA. Before release of the device, a careful "wiggle manoevre" was performed to assess the stability of the implanted device and to proof the inability to embolize to the aorta. CONCLUSIONS: With the new Occlutech® PDA Occluder closure of very large PDAs and PAH is feasible and efficient. The wider pulmonary artery end of the Occlutech® PDA Occluder offers enhanced stability and reduces the risk of embolization. © 2016 Wiley Periodicals, Inc.

Treatment initiation in paediatric pulmonary hypertension: insights from a multinational registry.

Different treatment options for pulmonary hypertension have emerged in recent years, and evidence-based management strategies have improved quality of life and survival in adults. In children with pulmonary vascular disease, therapeutic algorithms are not so clearly defined; this study determined current treatment initiation in children with pulmonary hypertension in participating centres of a registry. Through the multinational Tracking Outcomes and Practice in Pediatric Pulmonary Hypertension registry, patient demographics, diagnosis, and treatment as judged and executed by the local physician were collected. Inclusion criteria were >3 months and <18 years of age and diagnostic cardiac catheterisation consistent with pulmonary hypertension (mean pulmonary arterial pressure ⩾25 mmHg, pulmonary vascular resistance index ⩾3 Wood units×m2, and mean pulmonary capillary wedge pressure ⩽12 mmHg). At diagnostic catheterisation, 217/244 patients (88.9%) were treatment naïve for pulmonary hypertension-targeted therapy. Targeted therapy was initiated after catheterisation in 170 (78.3%) treatment-naïve patients. A total of 19 patients received supportive therapy, 28 patients were not started on therapy, and 26 patients (10.7%) were on targeted treatment before catheterisation. Among treatment-naïve subjects, treatment was initiated with one targeted drug (n=112, 51.6%), dual therapy (n=39, 18%) or triple-therapy (n=5, 2.3%), and calcium channel blockers with one targeted medication in one patient (0.5%). Phosphodiesterase inhibitors type 5 were used frequently; some patients with pulmonary hypertension related to lung disease received targeted therapy. There is a diverse therapeutic approach for children with pulmonary hypertension with a need of better-defined treatment algorithms based on paediatric consensus for different aetiologies including the best possible diagnostic workup.

Feasibility and safety of cardiopulmonary exercise testing in children with pulmonary hypertension.

BACKGROUND: Cardiopulmonary exercise testing helps prognosticate and guide treatment in adults with pulmonary hypertension. Concerns regarding its feasibility and safety limit its use in children with pulmonary hypertension. We aimed to assess the feasibility and safety of cardiopulmonary exercise testing in a large paediatric pulmonary hypertension cohort. METHODS: We reviewed all consecutive cardiopulmonary exercise tests performed between March, 2004 and November, 2013. The exclusion criteria were as follows: height <120 cm, World Health Organization class IV, history of exercise-induced syncope, or significant ischaemia/arrhythmias. Significant events recorded were as follows: patient-reported symptoms, arrhythmias, electrocardiogram abnormalities, and abnormal responses of arterial O2 saturation. RESULTS: A total of 98 children underwent 167 cardiopulmonary exercise tests. The median age was 14 years (inter-quartile range 10-15 years). Peak oxygen uptake was 20.4±7.3 ml/kg/minute, corresponding to 51.8±18.3% of the predicted value. Peak respiratory quotient was 1.08±0.16. All the tests except two were maximal, being terminated prematurely for clinical reasons. Baseline Oxygen saturation was 93.3±8.8% and was 81.2±19.5% at peak exercise. A drop in arterial O2 saturation >20% was observed in 23.5% of the patients. Moreover, five patients (3.0%) experienced dizziness, one requiring termination of cardiopulmonary exercise testing; five children (3.0%) experienced chest pain, with early cardiopulmonary exercise test termination in one patient. No significant arrhythmias or electrocardiogram changes were observed. CONCLUSION: Exercise testing in non-severely symptomatic children with pulmonary hypertension is safe and practical, and can be performed in a large number of children with pulmonary hypertension in a controlled environment with an experienced team. Side-effects were not serious and were resolved promptly with test termination.

Clinical features of paediatric pulmonary hypertension: a registry study.

BACKGROUND: Paediatric pulmonary hypertension, is an important cause of morbidity and mortality, and is insufficiently characterised in children. The Tracking Outcomes and Practice in Pediatric Pulmonary Hypertension (TOPP) registry is a global, prospective study designed to provide information about demographics, treatment, and outcomes in paediatric pulmonary hypertension. METHODS: Consecutive patients aged 18 years or younger at diagnosis with pulmonary hypertension and increased pulmonary vascular resistance were enrolled in TOPP at 31 centres in 19 countries from Jan 31, 2008, to Feb 15, 2010. Patient and disease characteristics, including age at diagnosis and at enrolment, sex, ethnicity, presenting symptoms, pulmonary hypertension classification, comorbid disorders, medical and family history, haemodynamic indices, and functional class were recorded. Follow-up was decided by the patients' physicians according to the individual's health-care needs. FINDINGS: 362 of 456 consecutive patients had confirmed pulmonary hypertension (defined as mean pulmonary artery pressure ≥25 mm Hg, pulmonary capillary wedge pressure ≤12 mm Hg, and pulmonary vascular resistance index ≥3 WU/m(-2)). 317 (88%) patients had pulmonary arterial hypertension (PAH), which was idiopathic [IPAH] or familial [FPAH] in 182 (57%), and associated with other disorders in 135 (43%), of which 115 (85%) cases were associated with congenital heart disease. 42 patients (12%) had pulmonary hypertension associated with respiratory disease or hypoxaemia, with bronchopulmonary dysplasia most frequent. Finally, only three patients had either chronic thromboembolic pulmonary hypertension or miscellaneous causes of pulmonary hypertension. Chromosomal anomalies, mainly trisomy 21, were reported in 47 (13%) of patients with confirmed disease. Median age at diagnosis was 7 years (IQR 3-12); 59% (268 of 456) were female. Although dyspnoea and fatigue were the most frequent symptoms, syncope occurred in 31% (57 of 182) of patients with IPAH or FPAH and in 18% (eight of 45) of those with repaired congenital heart disease; no children with unrepaired congenital systemic-to-pulmonary shunts had syncope. Despite severe pulmonary hypertension, functional class was I or II in 230 of 362 (64%) patients, which is consistent with preserved right-heart function. INTERPRETATION: TOPP identifies important clinical features specific to the care of paediatric pulmonary hypertension, which draw attention to the need for paediatric data rather than extrapolation from adult studies. FUNDING: Actelion Pharmaceuticals.

Diagnostic evaluation of paediatric pulmonary hypertension in current clinical practice.

Current paediatric pulmonary hypertension (PH) diagnostic algorithms include some testing specifically for paediatrics, but it is unclear if this is used in clinical practice. We describe the current diagnostic workup of the TOPP (Tracking Outcomes and Practice in Paediatric Pulmonary hypertension) registry for suspected PH. We investigated 456 patients enrolled until February 2010. The majority had ECGs (94%), echocardiograms (96%) and/or chest radiographs (89%) performed and these were the noninvasive tests most frequently used for evaluation of suspected PH. No patient had all three tests considered normal, suggesting the potential for the combined use to rule out PH. For evaluation of complications associated with heart catheterisation (HC) we analysed a total of 908 HCs reported until February 2012. Of these, 554 were at diagnosis and 354 in follow-up. Complications were reported in 5.9% with five deaths considered related to HC, suggesting a higher rate of HC complications compared to adult studies. However, current recommendations support HC in paediatric PH. A proper application of the risk/benefit ratio for HC requires further data. Most children did not undergo the diagnostic workup currently recommended for adults, which highlights either incomplete awareness of current guidelines and/or challenges their appropriateness for children.

Atrial septal defect closure with an Amplatzer septal occluder fenestrated with a coronary stent in a child with pulmonary arterial hypertension.

The presence of an atrial septal defect in pulmonary hypertension has benefits and detractions. Even in idiopathic pulmonary arterial hypertension, a significant left-to-right shunt at atrial level may increase the pulmonary arterial pressure and exacerbate the disease. However, it is well recognised that the presence of an atrial communication may be protective in subgroups with severe disease, allowing maintenance of cardiac output during times of increased pulmonary resistance. In the present paper, we present the case of a young boy with significant idiopathic pulmonary arterial hypertension and an atrial septal defect. We report our technique of septal occlusion using a device to decrease left-to-right shunting with concomitant stent insertion in that device to maintain the potential for right-to-left shunting during times of high pulmonary arterial pressure.

Evaluation of the diagnostic and prognostic potential of optical coherence tomography (OCT) of the pulmonary arteries during standardised right heart catheterisation in patients with pulmonary hypertension: a cross-sectional single-centre experience.

Background: Pulmonary hypertension (PH) is diagnosed based on an invasive evaluation of the mean pulmonary artery (PA) pressure. The morphological assessment of the pulmonary arteries was only recently not feasible. With the advent of optical coherence tomography (OCT)-imaging, an accessible tool allows to study PA morphology longitudinally. The primary hypothesis was that OCT distincts the PA structure of PH patients from control subjects. The secondary hypothesis was that PA wall thickness (WT) correlates with the progression of PH. Methods: This is a retrospective monocentric study of 28 paediatric patients with (PH group) and without PH (control group) who had undergone cardiac catheterisation including OCT imaging of the PA branches. OCT parameters analysed were WT and the quotient of WT and diameter (WT/DM) and those were compared between the PH group and the control group. In addition, the OCT parameters were aligned with the haemodynamic parameters to evaluate the potential of OCT as a risk factor for patients with PH. Results: WT and WT/DM in the PH group were significantly higher compared to the control group {WT: 0.150 [0.230, range (R): 0.100-0.330] vs. 0.100 [0.050, R: 0.080-0.130] mm, P<0.001; WT/DM: 0.06 [0.05] vs. 0.03 [0.01], P=0.006}. There were highly significant correlations between WT and WT/DM with the haemodynamic parameters mean pulmonary arterial pressure (mPAP) [Spearman correlation coefficient (rs) =0.702, P<0.001; rs=0.621, P<0.001], systolic pulmonary arterial pressure (sPAP) (rs=0.668, P<0.001; rs=0.658, P<0.001) and WT and pulmonary vascular resistance (PVR) (rs=0.590, P=0.02). Also, there was a significant correlation between WT and WT/DM and the risk factors quotient of mPAP and mean systemic arterial pressure (mSAP) (mPAP/mSAP) (rs=0.686, P<0.001; rs=0.644, P<0.001) and pulmonary vascular resistance index (PVRI) (rs=0.758, P=0.002; rs=0.594, P=0.02). Conclusions: OCT can detect significant differences in WT of the PA in patients with PH. Furthermore, the OCT parameters correlate significantly with haemodynamic parameters and risk factors for patients with PH. More investigations are required to evaluate to what extent the impact of OCT can contribute to the clinical care of children with PH.

Phrenic nerve injury after image-guided insertion of a tunnelled right internal jugular central venous catheter.

Central venous catheters (CVC) are now commonly inserted by radiologists. Although complications are infrequent, they must be avoided where possible and recognized when they occur. We present a 10-year-old boy who developed right hemidiaphragmatic paralysis, requiring surgical plication, following US-guided insertion of a tunnelled right internal jugular CVC. The needle trajectory for internal jugular puncture must be planned to avoid the phrenic nerve.

Assessment of coronary flow reserve in the coronary sinus by cine 3T-magnetic resonance imaging in young adults after surgery for tetralogy of Fallot.

This study aimed to evaluate CFR by assessing blood flow in the coronary sinus and systemic endothelial function measured by FMD of the brachial artery in an open prospective study of 10 control subjects and 10 patients (ages, 15-25 years) who have undergone surgical TOF repair. Reduced ventricular function, impaired exercise capacity, and ventricular arrhythmia have been proposed as risk factors for sudden cardiac death after surgical repair of TOF. Some of this may be related to impaired myocardial perfusion. A 3.0T GE Signa Excite scanner was used to achieve phase-contrast, velocity-encoding cine magnetic resonance imaging in the coronary sinus before and during infusion with adenosine (0.14 mg/kg/min). FMD was measured in the brachial artery before arterial occlusion and 5 min afterward. The TOF group demonstrated significantly higher volumetric blood flow in the coronary sinus (282 ± 63 ml/min) than the normal control subjects at rest (184 ± 57 ml/min) (P = 0.006). During adenosine infusion, this difference disappeared. The CFR was 2.00 ± 0.43 in the control group and 1.19 ± 0.34 in the TOF group (P = 0.002). No correlation between FMD and CFR was observed in the study group (r (s) = 0.61, n = 8, P = 0.15). This study showed a reduced CFR due to a higher blood flow of the subject at rest in the TOF group. This reduced CFR may disable a normal adaptation to increased oxygen demand during exercise and increase myocardial vulnerability to reduced blood supply postoperatively for TOF patients with coronary heart disease.

Validity of the LaFarge equation for estimation of oxygen consumption in ventilated children with congenital heart disease younger than 3 years--a revisit.

BACKGROUND: The LaFarge equation is the most commonly used equation to estimate oxygen consumption (Vo(2)) in patients of all ages with congenital heart disease, although it was generated in patients older than 3 years. We sought to determine the validity of the LaFarge equation in estimating Vo(2) in children younger than 3 years undergoing cardiac catheterization with general anesthesia. METHODS: Vo(2) was measured directly using respiratory mass spectrometry in 75 sedated, paralyzed, and mechanically ventilated children in the pediatric cardiac catheterization laboratory. Age ranged from 0.13 to 24 years; 40 children being younger than 3 years. Estimated values for Vo(2) were calculated using the LaFarge equation for all patients. The agreement between measured and estimated Vo(2) was evaluated by the bias and limits of agreement in the 2 age groups. Regression analysis was used to analyze the influence of age on the agreement. RESULTS: A failure of agreement between measured and estimated Vo(2) was noted in both groups of children. As compared to the older group of patients, the agreement was significantly poorer in children younger than 3 years, with a significantly greater overestimation introduced by the LaFarge equation (11% +/- 21% vs 53% +/- 52%, P < .0001). CONCLUSION: The LaFarge equation introduces significant error in the estimation of Vo(2) in ventilated patients with congenital heart disease of all ages, particularly in children younger than 3 years.

Pharmacokinetic and clinical profile of a novel formulation of bosentan in children with pulmonary arterial hypertension: the FUTURE-1 study.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: * Exposure to bosentan was lower in paediatric pulmonary arterial hypertension (PAH) patients treated with the marketed adult formulation at a dose of about 2 mg kg(-1) when compared with adult PAH patients. * In healthy adult subjects, bosentan pharmacokinetics are less than dose-proportional at doses of >or=500 mg. WHAT THIS STUDY ADDS: * The pharmacokinetics of a new paediatric bosentan formulation were characterized in paediatric PAH patients. * The level of exposure to bosentan as observed in adult PAH patients cannot be reached in paediatric patients with b.i.d. dosing. * In paediatric PAH patients, nondose-proportional pharmacokinetics of bosentan occur at lower doses when compared with healthy adult subjects. AIM: To show equivalent bosentan exposure in paediatric patients with pulmonary arterial hypertension (PAH) when compared with a cohort of historical controls of adult PAH patients using a newly developed paediatric formulation. METHODS: Thirty-six paediatric PAH patients were enrolled in this multicentre, prospective, open-label, noncontrolled study and treated for 4 weeks with bosentan 2 mg kg(-1) b.i.d. and then for 8 weeks with 4 mg kg(-1) b.i.d. Blood samples were taken for pharmacokinetic purposes. Exploratory efficacy measurements included World Health Organization (WHO) functional class and parent's and clinician's Global Clinical Impression scales. RESULTS: Comparing children with a historical group of adults, the geometric mean ratio (90% confidence interval) of the area under the plasma concentration-time curve was 0.54 (0.37, 0.78), i.e. children had lower exposure to bosentan than adults. Bosentan concentrations following doses of 2 and 4 mg kg(-1) were similar. Improvements in WHO functional class and the Global Clinical Impression scales occurred mainly in bosentan-naive patients, whereas the rare worsenings occurred in patients already on bosentan prior to study initiation. The paediatric formulation was well accepted and bosentan well tolerated in this study. No cases of elevated liver enzymes or anaemia were reported. CONCLUSIONS: Exposure to bosentan, as shown comparing the results from this study with those from a study in adults, was different in paediatric and adult PAH patients. Since FUTURE-1 and past studies suggest a favourable benefit-risk profile for bosentan at 2 mg kg(-1) b.i.d., this dose is recommended for children with PAH. The new paediatric formulation was well tolerated.

The risk of infective endocarditis following interventional pulmonary valve implantation: A meta-analysis.

BACKGROUND: Interventional percutaneous pulmonary valve implantation (PPVI) was first reported in 2000. Today, two different valves are certified for this procedure [i.e. Medtronic Melody® valve (Medtronic, Dublin, Ireland) and Edwards Sapien™ valve (Edwards Lifesciences, Irvine, CA, USA)]. For a decade, studies have reported an increasing risk of infective endocarditis (IE) after PPVI; as patients for PPVI are usually younger, even a low annual incidence of IE is important. However, the overall incidence and potential differences between the valves remain unclear. METHODS: A systematic literature search was performed in the databases Medline, Cochrane Library, and Embase including the clinical trials register. The aim was to summarize and compare the cumulative incidence of IE after PPVI. Using a sensitivity analysis we set the incidence rates of the two valve types in ratio with a normal population. RESULTS: A total of 967 publications were identified searching for "pulmonary valve implantation," "PPVI," and 47 publications were used for final analysis. A total 3616 patients with Melody® valves and 501 with Sapien™ valves were included. IE after PPVI occurred in 214 patients with Melody® valves and in 5 patients only with Sapien™ valves. The pooled incidence for Melody® and Sapien™ valves was 4.9% (95% CI: 3.6-6.2) and 1.3% (95% CI: 0.3-2.3), respectively. Chi-square test was significant. The sensitivity analysis showed that the incidence rate ratio was 252.1 (95% CI: 187.6-338.6) for Melody® valves and for Sapien™ valves 2.7 (95% CI: 0.8-9.2). CONCLUSIONS: At present, there is an important difference for the risk of IE after PPVI. To reduce the risk of post PPVI endocarditis, a careful valve selection in favor of the Sapien™ valves seems to be beneficial.

Differentiation of Impaired From Preserved Hemodynamics in Patients With Fontan Circulation Using Real-time Phase-velocity Cardiovascular Magnetic Resonance.

PURPOSE: Progressive impairment of hemodynamics in patients with Fontan circulation is common, multifactorial, and associated with decreased quality of life and increased morbidity. We sought to assess hemodynamic differences between patients with preserved (preserved Fontans) and those with impaired circulation (impaired Fontans) after pulmonary vasodilation using oxygen and under forced breathing conditions. MATERIALS AND METHODS: Real-time phase-contrast cardiovascular magnetic resonance was performed using non-ECG triggered echo-planar imaging (temporal resolution=24 to 28 ms) in the ascending aorta (AAo) and superior vena cava (SVC)/inferior vena cava (IVC) on room air, after 100% oxygen inhalation (4 L/min; 10 min) and on forced breathing in 29 Fontan patients (17.2±7.3 y) and in 32 controls on room air (13.4±3.7 y). The simultaneously recorded patients' respiratory cycle was divided into 4 segments (expiration, end-expiration, inspiration, and end-inspiration) to generate respiratory-dependent stroke volumes (SVs). The imaging data were matched with physiological data and analyzed with home-made software. RESULTS: The mean SVi (AAo) was 46.1±11.1 mL/m in preserved Fontans versus 30.4±6.2 mL/m in impaired Fontans (P=0.002) and 51.1±6.9 mL/m in controls (P=0.107). The cutoff value for differentiation of Fontan groups was SVi (AAo, end-expiratory) of 32.1 mL/m. After hyperoxygenation, the mean SVi (AAo) increased to 48.7±12.7 mL/m in preserved Fontans (P=0.045) but remained unchanged in impaired Fontans (31.1±5.8 mL/m, P=0.665). Simultaneously, heart rates decreased from 75.2±15.9 to 70.8±16.4 bpm (preserved; P=0.000) but remained unchanged in impaired circulation (baseline: 84.1±9.8 bpm, P=0.612). Compared with physiological respiration, forced breathing increased the maximum respiratory-related cardiac index difference (ΔCImax) in preserved Fontans (SVC: 2.5-fold, P=0.000; and IVC: 1.8-fold, P=0.000) and to a lower extent in impaired Fontans (both veins, 1.5-fold; P(SVC)=0.011, P(IVC)=0.013). There was no impact on mean blood flow. CONCLUSIONS: Oxygen affected the pulmonary vascular system by vasodilation and increased SVi in preserved Fontans but had no effect on impaired Fontans. Forced breathing increased ΔCImax but did not change the mean blood flow by sole activation of the ventilatory pump. End-expiratory aortic SVi represents a valuable measure for classifying the severity of Fontan hemodynamics impairment.

Management of pediatric patients after implantation of the Berlin Heart EXCOR ventricular assist device.

Within the last 16 years, the Berlin Heart EXCOR systems have been used for circulatory support in 73 infants and children up to 17 years of age (mean, 7 years) with severe circulatory failure resistant to pharmacological therapy at our institution. These were patients with cardiomyopathy, fulminant myocarditis, end-stage congenital cardiac defects, and acute heart failure after congenital heart surgery. Mean EXCOR support time was 36 days (range, 1 to 420 days). Forty-four patients (62%) survived up to transplantation or after weaning and 37 (51%) of them, including 9 infants, were discharged home. These results in patients with very advanced disease have improved significantly during the past few years as the result of technical developments and growing experience in the treatment of patients on the device and in postoperative care. The following article gives answers to five questions frequently asked about intensive care unit treatment while on the device, anticoagulation and additional medical support during left ventricular or biventricular support, the daily treatment of the children, and options for the weaning procedure.

Intravenous sildenafil is a potent pulmonary vasodilator in children with congenital heart disease.

BACKGROUND: Increased pulmonary vascular resistance (PVR) because of congenital heart disease (CHD) may be caused by a dysfunction in endogenous pulmonary endothelial nitric oxide (NO) production. In other forms of pulmonary vascular disease with increased PVR, an elevated activity of a phosphodiesterase type 5 (PDE-5), responsible for the degradation of cyclic guanidine monophosphate (cGMP), the second messenger of endothelially produced NO, has been demonstrated. This study compares the effects of inhaled NO before and after the specific inhibition of the PDE-5 by intravenous sildenafil (Viagra) in pre- and postoperative children with increased PVR because of CHD. METHODS AND RESULTS: 12 children with congenital heart disease (age 0.2 to 15.7 years, median 2.4 years) and increased mean pulmonary arterial pressure, and 12 postoperative children (age 0.11 to 0.65 years, median 0.32 years) with increased PVR (8.3+/-1.0 Wood Units*m2) were studied during cardiac catheterization ("cath laboratory"), or within 2 hours after return from cardiac surgery ("post op"), respectively. All were sedated, tracheally intubated and paralyzed. During alveolar hyperoxygenation (FiO2=0.65), the effects of inhaled NO (20 ppm) were compared before and after the stepwise infusion of sildenafil ("cath laboratory", 1 mg/kg; post op, 0.25 mg/kg). Intravenous sildenafil more effectively reduced PVR than NO (11.5% versus 4.3% in the "cath laboratory" patient group, P<0.05, and 25.8% versus 14.6% in the post op patient group, P=0.09. The increase in cGMP in response to NO was potentiated (2- to 2.4-fold) by PDE-5 inhibition. While the vasodilating effects of sildenafil showed pulmonary selectivity, its infusion was associated with increased intrapulmonary shunting in the postoperative patients (Qs/Qt=16.5+/-4.7% to 25.5+/-18.2% P=0.04). CONCLUSIONS: Intravenous sildenafil is as effective as inhaled NO as a pulmonary vasodilator in children with congenital heart disease. Although clinically insignificant in this study, increased intrapulmonary shunting with sildenafil may be disadvantageous in some patients after CHD surgery.

Early clinical results of the telemetric adjustable pulmonary artery banding FloWatch-PAB.

BACKGROUND: Adjustment of pulmonary artery banding (PAB) may be a challenging procedure in complex congenital heart defects. Whatever the technique used, subsequent re-operations are frequently needed to control the pulmonary blood flow or pressures. OBJECTIVE: To report the efficacy of a new telemetric adjustable PAB (FloWatch-PAB) operated with the help of an external control unit that transmits to the implant energy and commands to further narrow or release the pulmonary artery using radiofrequency waves. METHODS AND RESULTS: In a multicenter, prospective, nonrandomized, single-arm clinical investigation, 13 children (median age, 4.5 months; range, 6 days to 11 years; median weight, 4.2 kg; range, 3.1 to 27 kg) underwent implantation of the FloWatch-PAB through median sternotomy in 8 and left thoracotomy in 5. The diagnosis was multiple ventricular septal (VSD) defects with complex anatomy in 3, single ventricle without pulmonary stenosis in 2, VSD with elevated pulmonary vascular resistance (PVR) in 2, atrio-ventricular canal (AVC) with elevated pulmonary vascular resistance in 1, AVC with diminutive right ventricle in 1, complex transposition of the great arteries in 3, and pulmonary atresia with complex pulmonary arteries anatomy in 1. All patients had normosystemic systolic pulmonary artery pressure. Additional procedures were performed in 7: atrial septectomy in 2, double aortic arch division in 1, patent ductus arteriosus ligation in 2, and coarctation repair in 2. There were no early or late deaths or device-related complications in a mean follow-up of 24 weeks (range, 18 to 42 weeks). A mean of 5.8 telemetric regulations per patient using the FloWatch-PAB were required to adjust the tightening of the PAB to the clinical needs (narrowing 74%, releasing 26%). At last follow-up, systolic pulmonary artery pressure was within normal range in all patients but 1. Systemic oxygen saturation demonstrated optimal regulation of the pulmonary blood flow in all according to each specific defect. Four patients were successfully corrected (VSD closure, AVSD repair, and 2 arterial switches with VSD closure). The device was easily removed and the pulmonary artery re-expanded spontaneously. CONCLUSIONS: This new device is safe and allows optimal adjustment of PAB in complex heart defects. In children requiring PAB, the use of this technology can obviate the need for early re-operations and appears to be a valuable option in the panel of surgical alternatives for selected infants.

Magnetic resonance imaging analysis of right ventricular pressure-volume loops: in vivo validation and clinical application in patients with pulmonary hypertension.

BACKGROUND: The aims of this study were to validate MRI-derived right ventricular (RV) pressure-volume loops for assessment of RV myocardial contractility and then to apply this technique in patients with chronic RV pressure overload for assessment of myocardial contractility, ventricular pump function, and VA coupling. METHODS AND RESULTS: Flow-directed catheters were guided under MR fluoroscopy (1.5 T) into the RV for invasive pressure measurements. Simultaneously, ventricular volumes and myocardial mass were assessed from cine MRI. From sampled data, RV pressure-volume loops were constructed, and maximal ventricular elastance indexed to myocardial mass (E(max_i)) was derived by use of a single-beat estimation method. This MRI method was first validated in vivo (6 swine), with conductance techniques used as reference. Bland-Altman test showed good agreement between methods (E(max_i)=5.1+/-0.5 versus 5.8+/-0.7 mm Hg x mL(-1) x 100 g(-1), respectively; P=0.08). Subsequently, the MRI method was applied in 12 subjects: 6 control subjects and 6 patients with chronic RV pressure overload from pulmonary hypertension. In these patients, indexes of RV pump function (cardiac index), E(max_i), and VA coupling (E(max)/E(a)) were assessed. In patients with pulmonary hypertension, RV pump function was decreased (cardiac index, 2.2+/-0.5 versus 2.9+/-0.4 L x min(-1) x m(-2); P<0.01), myocardial contractility was enhanced (E(max_I), 9.2+/-1.1 versus 5.0+/-0.9 mm Hg x mL(-1) x 100 g(-1); P<0.01), and VA coupling was inefficient (E(max)/E(a), 1.1+/-0.3 versus 1.9+/-0.4; P<0.01) compared with control subjects. CONCLUSIONS: RV myocardial contractility can be determined from MRI-derived pressure-volume loops. Chronic RV pressure overload was associated with reduced RV pump function despite enhanced RV myocardial contractility. The proposed MRI approach is a promising tool to assess RV contractility in the clinical setting.