The "Dog Bone Technique" A Novel Easy and Safe Catheter Maneuver for Aortic Arch and Coarctation Stenting.

BACKGROUND: Various techniques are described to facilitate stable stent implantation in aortic arch stenosis or coarctation. We describe an alternative technique, which due to its unique appearance during stent implantation, we have named "Dog Bone Technique" (DBT). TECHNIQUE: The stent/balloon assembly is placed across the stenosis, the long sheath is retrieved to uncover the distal 20-50% of the stent. The balloon is inflated with the pressure inflator just to expand slightly the stent. Thereafter the sheath is pulled back and the proximal end is uncovered and partially inflated; therewith the assembly takes the typical "dog bone" shape before complete inflation and final positioning. Repositioning of the stent and control angiography is possible at each time of this procedure. RESULTS: Between 1/2010 and 12/2014 we implanted 91 stents in 87 patients (mean age 20.2 years). About 71 patients had native or re-coarctation and 16 patients had transverse aortic arch stenosis. In 38 patients (44%) a pharmacological exercise test with Orciprenaline was performed during implantation resulting in high-cardiac output. In none of the patients reduction of cardiac output by adenosine or a rapid pacing of the right ventricle was required for stable stent implantation. All stents were implanted in the targeted position using this single balloon technique. There were no acute or short-term complications detected. CONCLUSION: DBT is a safe and feasible technique for aortic stent implantation even at high-cardiac output. Other additional techniques for stent placement are not necessary to obtain a stable final position in the target region.

Long-Term Mechanical Circulatory Support in Pediatric Patients.

This retrospective study reviews our results regarding the long-term support in pediatric patients using two ventricular assist systems between January 2008 and April 2014. We implanted the Berlin Heart EXCOR in 29 patients (median age 3.4 years [interquartile range (IQR) 0.2-16.5], median weight 13 kg [IQR 4.2-67.2]). Twenty-two patients (75.8%) received a left ventricular assist device. Three patients (10.3%) had single-ventricle physiology. One patient (3.4%) had mechanical mitral valve prosthesis. The HeartWare System was implanted in nine patients. The median age was 15.6 years (IQR 12.2-17.9), and the median weight was 54.9 kg (IQR 27.7-66). In the Berlin Heart group, the median support time was 65 days (IQR 4-619), with 3647 days of cardiac support. Nineteen patients (65.5%) were transplanted, six patients (20.7%) recovered, one patient (3.4%) is on support, and three patients (10.3%) died on support. Survival rate was 89.7%. Fourteen blood pumps had been exchanged. Four patients (13.8%) had local signs of infection, and three patients (10.3%) had neurological complications. In the HeartWare group, the median support time was 180 days (IQR 1-1124), with 2839 days of cardiac support. Four patients (44.4%) had local signs of infection, and three (33.3%) had neurological complications. Eight patients (88.9%) have been transplanted, and one patient (11.1%) died on support. Survival rate was 88.9%. Excellent survival is possible after long-term mechanical circulatory support in patients with two- and single-ventricle physiology with a low rate of adverse events.

Bovine Jugular Veins versus Homografts in the Pulmonary Position: An Analysis across Two Centers and 711 Patients-Conventional Comparisons and Time Status Graphs as a New Approach.

BACKGROUND: Various diseases and diversity in implantation ages, together with evolving diagnostic and therapeutic options, hinder comparative evaluations of long-term outcomes for valved conduits used for reconstruction of the right ventricular outflow tract (RVOT). We combined two common evaluation methods to optimally use information obtained by pooling the raw data from two high volume centers, each with very regular follow-up procedures, with the aim of analyzing durability differences between conventional homografts and bovine jugular veins. PATIENTS AND METHODS: In the period 1985 to 2012, a total of 444 bovine jugular veins and 267 homografts were implanted, and 6,738 postoperative examinations took place. Evaluations included age-stratified Kaplan-Meier analyses, Cox regression models, and time status graphs, the third showing age-group stratified, time-related frequencies of intact, insufficient, stenotic, both insufficient and stenotic, and postinterventional conduits below the freedom from explantation curve. They take into account interventions, explantations, and the nonterminal character of echocardiographic findings. RESULTS: The durability of intact bovine jugular veins in children and young adults is not inferior to that of homografts. Averaged over the first 12 years after implantation, the age groups < 25 years in fact showed advantages for bovine jugular vein recipients. The average fraction of patients younger than 25 years whose conduits were not explanted, postinterventional, stenotic, insufficient, or stenotic and insufficient was at least 10% higher in recipients of bovine jugular veins than in homograft recipients. CONCLUSION: According to the time status graphs, the use of bovine jugular veins for RVOT in patients younger than 25 years appears to lead to superior results when compared with cryopreserved homografts.

Representativeness of the German National Register for Congenital Heart Defects: a clinically oriented analysis.

BACKGROUND: Approximately 6000 children are born with CHD in Germany each year. It is increasingly rare that these children die from their chronic illness. In the present study, data recorded in the National Register for Congenital Heart Defects with respect to the prevalence of specific lesions and sex distribution are compared with that recorded in a published German prevalence study (Prevalence Study) and with the meta-analysis by van der Linde et al. METHODS: A descriptive data analysis was performed using a minimal data set. The demographic data included sex and birth year; the medical data comprised the cardiovascular diagnosis according to the short list of the International Paediatric and Congenital Cardiac Code. RESULTS: As the data analysis shows, the National Register is a clinical register including primarily clinical cases/cases relevant to healthcare. The prevalence values and sex ratios recorded in the register are closer to the values given in the literature than those determined by the Prevalence Study. Severe CHD was slightly over-represented in the National Register compared with the van der Linde et al meta-analysis. The deviations with respect to prevalence values are within an acceptable range. CONCLUSION: With its 48,000 patients, the National Register plays a unique and important role for research in the field of CHD. Samples from the National Register can be used as a gold standard for future studies, as the patient population registered in it can be considered representative of CHD in Germany and Europe.

Implantation of the new Nit-Occlud PDA-R device in children below 10 kilogram.

BACKGROUND: Interventional closure of patent ductus arteriosus (PDA) has become a common and safe procedure in most pediatric cath labs. Interventional treatment of PDAs still remains a challenge in those children with low body weight and a large PDA. The Nit-Occlud PDA-R® device was developed and especially designed for large PDAs. We report our most recent experience in children with a body weight lower than 10 kg. MATERIALS AND METHODS: The PDA-R® device was used in seven children (age 1-10, median 6 months) with a body weight from 4.1 to 9.7 kg (median 5.9 kg): ductal length was 12 mm (median), with a large ampulla (median 9 mm) which exceeded the diameter of the aorta (median 6 mm) and large diameter (median minimal diameter 4 mm). In six cases, the Nit-Occlud PDA-R was selected with an aortic disc of 12 mm and in one case an occluder with an aortic disc of 14 mm. RESULTS: Occlusion of the PDA was documented by angiography and/or echocardiography in all cases. At a mean follow-up of 21.4 months, no flow obstruction to the left or right pulmonary artery or new onset coarctation of the aorta was noted. CONCLUSIONS: The Nit-Occlud PDA-R® device is suitable in children with a body weight below 10 kg when a relative large PDA is present.

Single center experience: Implantation failures, early, and late complications after implantation of a partially biodegradable ASD/PFO-device (BioStar®).

INTRODUCTION: In the search for a biodegradable device that leaves nothing but the tissue of the patient after complete endotheliazation and absorption, the BioSTAR® device was introduced in 2007 (CE Mark in European community and HPB in Canada) for ASD and PFO closure. It consists of a metal framework covered by a biodegradable membrane generated from a layer of porcine collagen that is broken down and absorbed over time. In a sheep model, the results were promising, showing complete closure of the defect with degradation of approximately 90% of the implanted membrane material after two years. METHODS: We report a retrospective analysis of implantation failures, early and late complications in a series of 34 patients with 30 implanted BioStar® devices in a single center with a total follow-up of more than 75 patient years. RESULTS: We report 12% of implantation failures, 9% of early and 12% of late complications. Implantation failures include one embolized device, which was interventionally retrieved. Early complications were exclusively rhythm disturbances, one patient needed electrical and pharmacological therapy. Four relevant late complications occurred. One device required explantation after 61 days because of recurrent severe fever episodes, severe headache, and malaise that subsequently subsided after device removal. One patient presented with Dressler's syndrome with pericardial effusion 5 month after implantation requiring pericardiocentesis and steroid treatment. One device showed a central residual shunt that was not clearly seen initially. Finally, one device was explanted after hemorrhagic pericardial effusion due to perforation of an arm of the frame through the right atrial roof into the pericardial fold after 19 months. CONCLUSION: We conclude that implantation of the Biostar® device is difficult in patients with deficient aortic rims and early complications are similar to those seen in other devices. Of importance, the late complications seen with the Biostar® device might be attributable to specific material and immunological properties of the partially biodegradable device. Although a biodegradable device might theoretically be more favorable more efforts for optimization of these devices have to be taken.

The "Polar Light Sign" is a useful tool to detect discrete membranous supravalvular mitral stenosis.

Mitral valve stenosis caused by a discrete supravalvular membrane is a rare congenital malformation haemodynamically leading to significant mitral valve stenosis. When the supravalvular mitral stenosis consists of a discrete supravalvular membrane adherent to the mitral valve, it is usually not clearly detectable by routine echocardiography. We report about the typical echocardiographic finding in three young patients with this rare form of a discrete membranous supravalvular stenosis caused by a membrane adherent to the mitral valve. These cases present a typical echocardiographic feature in colour Doppler generated by the pathognomonic supramitral flow acceleration. Whereas typical supravalvular mitral stenosis caused by cor triatriatum or a clearly visible supravalvular ring is easily detectable by echocardiography, a discrete supravalvular membrane adjacent to the mitral valve leaflets resembling valvular mitral stenosis is difficult to differentiate by routine echocardiography. In our opinion, this colour phenomenon does resemble the visual impression of polar lights in the northern hemisphere; owing to its typical appearance, it may therefore be named as "Polar Light Sign". This phenomenon may help to detect this anatomical entity by echocardiography in time and therefore improve the prognosis for repair.

Percutaneous closure of atrial septal defects in spontaneously breathing children under deep sedation: a feasible and safe concept.

Interventional cardiac catheterization in children and adolescents is traditionally performed with the patient under general anesthesia and endotracheal intubation. However, percutaneous closure of atrial septum defect (ASD) without general anaesthesia is currently being attempted in a growing number of children. The study objective was to evaluate the success and complication rate of percutaneous ASD closure in spontaneously breathing children under deep sedation. Retrospective single centre cohort study of consecutive children undergoing percutaneous ASD closure at a tertiary care pediatric cardiology centre. Transesophageal echocardiography (TEE) and percutaneous ASD closure were performed with the patient under deep sedation with intravenous bolus of midazolam and ketamine for induction and propofol continuous infusion for maintenance of sedation in spontaneously breathing children. One hundred and ninety-seven patients (median age 6.1 years [minimum 0.5; maximum 18.8]) underwent TEE and ASD balloon sizing. Percutaneous ASD closure was attempted in 174 patients (88 %), and device implantation was performed successfully in 92 %. To achieve sufficient deep sedation, patients received a median ketamine dose of 2.7 mg/kg (0.3; 7) followed by a median propofol continuous infusion rate of 5 mg/kg/h (1.1; 10.7). There were no major cardiorespiratory complications associated with deep sedation, and only two patients (1 %) required endotracheal intubation due to bronchial obstruction immediately after induction of sedation. Seventeen patients (8 %) had minor respiratory complications and required frequent oral suctioning or temporary bag-mask ventilation. TEE and percutaneous ASD closure can be performed safely and successfully under deep sedation in spontaneously breathing children of all ages.

Evaluation of left ventricular torsion in children with hypertrophic cardiomyopathy.

AIMS: To evaluate the role of torsion in hypertrophic cardiomyopathy in children. METHODS: A total of 88 children with idiopathic hypertrophic cardiomyopathy (n = 24) and concentric hypertrophy (n = 20) were investigated with speckle-tracking echocardiography and compared with age- and gender-matched healthy controls (n = 44). RESULTS: In hypertrophic cardiomyopathy, we found increased torsion (2.8 ± 1.6 versus 1.9 ± 1.0°/cm [controls], p < 0.05) because of an increase in clockwise basal rotation (-8.7 ± 4.3° versus -4.9 ± 2.5° [controls], p < 0.001) and prolonged time to peak diastolic untwisting (3.7 ± 2.4% versus 1.7 ± 0.6% [controls] of cardiac cycle, p < 0.01), but no differences in peak untwisting velocities. Hypertrophic cardiomyopathy patients demonstrated a negative correlation between left ventricular muscle mass and torsion (r = -0.7, p < 0.001). In concentric hypertrophy, torsion was elevated because of increased apical rotation (15.1 ± 6.4° versus 10.5 ± 5.5° [controls], p < 0.05) without correlation with muscle mass. Peak untwisting velocities (- 202 ± 88 versus -145 ± 67°/s [controls], p < 0.05) were higher in concentric hypertrophy and time to peak diastolic untwisting was delayed (1.8 ± 0.8% versus 1.2 ± 0.6% [controls], p < 0.05). CONCLUSIONS: In contrast to an increased counterclockwise apical rotation in concentric hypertrophy, hypertrophic cardiomyopathy is characterised by predominantly enhanced systolic basal clockwise rotation. Diastolic untwisting is delayed in both groups. Torsion may be an interesting marker to guide patients with hypertrophic cardiomyopathy.

Left ventricular rotation and right-left ventricular interaction in congenital heart disease: the acute effects of interventional closure of patent arterial ducts and atrial septal defects.

BACKGROUND: Left ventricular rotation is physiologically affected by acute changes in preload. We investigated the acute effect of preload changes in chronically underloaded and overloaded left ventricles in children with shunt lesions. METHODS: A total of 15 patients with atrial septal defects (Group A: 7.4 ± 4.7 years, 11 females) and 14 patients with patent arterial ducts (Group B: 2.7 ± 3.1 years, 10 females) were investigated using 2D speckle-tracking echocardiography before and after interventional catheterisation. The rotational parameters of the patient group were compared with those of 29 matched healthy children (Group C). RESULTS: Maximal torsion (A: 2.45 ± 0.9°/cm versus C: 1.8 ± 0.8°/cm, p < 0.05), apical peak systolic rotation (A: 12.6 ± 5.7° versus C: 8.7 ± 3.5°, p < 0.05), and the peak diastolic torsion rate (A: -147 ± 48°/second versus C: -110 ± 31°/second, p < 0.05) were elevated in Group A and dropped immediately to normal values after intervention (maximal torsion 1.5 ± 1.1°/cm, p < 0.05, apical peak systolic rotation 7.2 ± 4.1°, p < 0.05, and peak diastolic torsion rate -106 ± 35°/second, p < 0.05). Patients in Group B had decreased maximal torsion (B: 1.8 ± 1.1°/cm versus C: 3.8 ± 1.4°/cm, p < 0.05) and apical peak systolic rotation (B: 8.3 ± 6.1° versus C: 13.9 ± 4.3°, p < 0.05). Defect closure was followed by an increase in maximal torsion (B: 2.7 ± 1.4°/cm, p < 0.05) and the peak diastolic torsion rate (B: -133 ± 66°/second versus -176 ± 84°/second, p < 0.05). CONCLUSIONS: Patients with chronically underloaded left ventricles compensate with an enhanced apical peak systolic rotation, maximal torsion, and quicker diastolic untwisting to facilitate diastolic filling. In patients with left ventricular dilatation by volume overload, the peak systolic apical rotation and the maximal torsion are decreased. After normalisation of the preload, they immediately return to normal and diastolic untwisting rebounds. These mechanisms are important for understanding the remodelling processes.

Effective valve opening area in the detection of dysfunctional aortic valve prostheses: a differentiated statistical analysis of this parameter including the introduction of minimal expected normal values as borderline to dysfunctional stenotic prostheses.

BACKGROUND: Dysfunction of heart valve prostheses (VP) is a life-threatening complication and the diagnosis remains difficult. The motivation for this study was to improve the detection of dysfunctional VP by optimizing application of the prosthetic effective orifice area (VA). For this reason the minimal expected normal VA (VA(expected)) was introduced. METHODS: We investigated echocardiographically 1,369 normally functioning aortic valve prostheses (AVP). Mean VA, transprosthetic peak (PPG) and mean pressure gradients (MPG) were evaluated to gain reference values depending on prosthetic size and construction principle. Mean VA(expected) was calculated by applying a simple formula that was developed empirically using statistical analyses. The results were compared with those of 65 dysfunctional AVPs. RESULTS: VA(expected) can be applied as a threshold between normal and dysfunctional stenotic AVP and showed a correct estimation in 87% of all normally functioning and 100% of dysfunctional stenotic VPs. The sensitivity for all prosthetic sizes is 1.0, independently of the constructional principle of the VP. Specificity ranged between 0.8 and 1.0, dependent on VP size. The formula representing VA(expected) is simple and can be executed easily. CONCLUSION: As nearly independent of stroke volume and in consideration of VA(expected), VA seems to have become one of the preferable parameters for detecting pathological stenotic AVPs echocardiographically. The additional application of PPG/MPG and other parameters permits prostheses with relevant isolated regurgitation and patient-prosthesis-mismatch to be distinguished.

Concomitant one-stage unifocalization and bidirectional Glenn procedure.

A concomitant one-stage unifocalization and bidirectional Glenn procedure was performed in a patient with a functionally single ventricle, pulmonary atresia, and major aortopulmonary collateral arteries (MAPCAs). Reconstruction of the absent central pulmonary artery was achieved using the MAPCAs as well as the autologous pericardium. After 1 year, cineangiography and cardiac catheterization showed an excellent result: well-developed pulmonary arteries as well as low pressure in the superior vena cava. To the best of our knowledge, this is the first report of a successful concomitant one-stage unifocalization and bidirectional Glenn procedure.

Left ventricular volumetry in healthy children and adolescents: comparison of two different real-time three-dimensional matrix transducers with cardiovascular magnetic resonance.

AIMS: To assess the accuracy of different hardware and software settings for left ventricular (LV) volume quantification in children using real-time three-dimensional echocardiography (RT3DE). METHODS AND RESULTS: The impact of different matrix transducers (IE 33, X3-1 and VIVID 7, V3) and quantification software settings [TOMTEC; contour-finding activity (tCFA) values ranging from 30 to 70 U] on the accuracy of LV indices was tested in 24 healthy children/adolescents (median = 12.6 years) and 25 paediatric patients with Tetralogy-of-Fallot (TOF) (median = 7.3 years) with abnormally shaped ventricles. RT3DE was compared with cardiovascular magnetic resonance (CMR) volumetry as reference. Best agreement (Bland-Altman analysis) was achieved using a tCFA value of 30 U. Applying the V3 device, end-diastolic volume (EDV) and end-systolic volume (ESV) were underestimated by 14.8 +/- 10.6% (mean +/- SD) and 11.2 +/- 16.3%, respectively (r = 9.42, P < 0.001 and r = 0.937, P = 0.003); with the X3-1 system 24.2 +/- 11.0 and 14.6 +/- 15.2%, respectively (r = 0.951, P < 0.001 and r = 0.912, P = 0.001). Negligible differences <1% (P = n.s.) between both transducers were detected applying a tCFA value of 70 U but with significant underestimation (EDV: approximately 35%, P < 0.001; ESV: approximately 26%, P < 0.001) compared with CMR. EDV and ESV of TOF patients were underestimated by 3.2 +/- 15.4 and 8.1 +/- 22.6%, respectively. Intra- and interobserver variability was <4%. CONCLUSION: In contrast to recommendations of the manufacturer, data sets from both RT3DE transducers showed acceptable agreement to CMR for volumetric parameters only for low tCFA. Fine-tuning of software settings is mandatory to improve accuracy.

Normal values of the pulmonary artery acceleration time (PAAT) and the right ventricular ejection time (RVET) in children and adolescents and the impact of the PAAT/RVET-index in the assessment of pulmonary hypertension.

New echocardiographic modalities including pulmonary artery acceleration time (PAAT) and right ventricular ejection time (RVET) are evolving to facilitate an early non-invasive diagnosis for pulmonary hypertension (PH) in adults. In children, PAAT depends on age, body surface area (BSA) and heart rate (HR) and is used to predict PH. Normal values of RVET and their role to predict PH in children are still missing. PAAT/RVET-index correlates negatively with PH. We hypothesized that this index is a good predictor for PH in children and adolescents independent of age, BSA and HR and RVET is significantly reduced in PH. PAAT and RVET of 401 healthy children and 30 PH-patients were measured using pulsed-wave-Doppler. PH was diagnosed in PH-group invasively. PAAT/RVET-index for both groups was calculated. Sensitivity and specificity in prediction of PH of PAAT, PAAT z-score and PAAT/RVET-index were compared. We demonstrated normal values of RVET in children. In the healthy group, PAAT and RVET correlated significant positive to age (p < 0.001), and BSA (p < 0.001) and negative to HR (p < 0.001). PAAT/RVET-index correlated weakly to age, BSA and HR (p < 0.001). Mean pulmonary artery pressure (PAPM) ranged in the PH-group from 27 to 82 mmHg (mean 44 mmHg). In predicting PH, RVET is significantly reduced (p < 0.001). Comparing area under the curve (AUC), the difference between sensitivity and specificity of PAAT/RVET-index < 0.29 and calculated PAAT cut-off-point (87 ms) was significant (p < 0.001). Equally, AUC comparison between PAAT/RVET-index < 0.29 and PAAT z-score of - 1.33 was significant (p = 0.008). PAAT/RVET-index < 0.29 represents a good predictor of PH with a 100% sensitivity and a 95.8% specificity. PAAT/RVET-index is a simple tool and facilitates prediction of PH independent from z-scores.

Centile Curves for Velocity-Time Integral Times Heart Rate as a Function of Ventricular Length: The Use of Minute Distance Is Advantageous to Enhance Clinical Reliability in Children.

BACKGROUND: The generation of velocity-time integrals (VTIs) from Doppler signals is an essential component of standard echocardiographic investigations. The most effective algorithm to compensate for growth in children has, however, not yet been identified. This study was initiated to establish pediatric reference values for VTI and to enhance the interpretability of those values, considering technical and physiological factors. METHODS: The echocardiographic data sets of healthy children and adolescents (N = 349; age range, 0-20 years) were recorded in a prospective approach and subsequently analyzed. In a pilot study, aortic and pulmonary VTIs were set in relation to the physiologic parameters of heart size as possible influencing parameters in a subgroup of children with comparable physical characteristics. The ratio with the smallest SD was taken as the base to generate centile curves using the LMS method. The clinical utility of the model was tested by examining patients (n = 80) with shunt lesions such as patent ductus arteriosus and atrial septal defect. RESULTS: Feasibility was 94.6% for aortic VTI and 92.8% for pulmonary VTI. The pilot study identified ventricular length and heart rate as suitable parameters with the lowest relative SDs and high correlations with VTI. Gender differences were not relevant for children <7 years of age, and with increasing age, SD increased because of higher stroke volume variations. The detection of increased aortic VTI was possible with sensitivity of 73% for patients with patent ductus arteriosus with moderate or large hemodynamically significant ductus arteriosus. Patients with atrial septal defects with enlarged right ventricles could be identified as having increased pulmonary VTI with sensitivity of 84%. CONCLUSIONS: These new reference values for VTI times heart rate as a function of ventricular length may be of specific clinical value to improve the assessment of cardiac function, therapeutic decision making, and follow-up in pediatric patients with heart disease.

Real-Time Three-Dimensional Echocardiography of the Left Ventricle-Pediatric Percentiles and Head-to-Head Comparison of Different Contour-Finding Algorithms: A Multicenter Study.

BACKGROUND: Real-time three-dimensional echocardiography (RT3DE) is a promising method for accurate assessment of left ventricular (LV) volumes and function, however, pediatric reference values are scarce. The aim of the study was to establish pediatric percentiles in a large population and to compare the inherent influence of different evaluation software on the resulting measurements. METHODS: In a multicenter prospective-design study, 497 healthy children (ages 1 day to 219 months) underwent RT3DE imaging of the LV (ie33, Philips, Andover, MA). Volume analysis was performed using QLab 9.0 (Philips) and TomTec 4DLV2.7 (vendor-independent; testing high (TomTec75) and low (TomTec30) contour-finding activity). Reference percentiles were computed using Cole's LMS method. In 22 subjects, cardiovascular magnetic resonance imaging (CMR) was used as the reference. RESULTS: A total of 370/497 (74.4%) of the subjects provided adequate data sets. LV volumes had a significant association with age, body size, and gender; therefore, sex-specific percentiles were indexed to body surface area. Intra- and interobserver variability for both workstations was good (relative bias ± SD for end-diastolic volume [EDV] in %: intraobserver: QLab = -0.8 ± 2.4; TomTec30 = -0.7 ± 7.2; TomTec75 = -1.9 ± 6.7; interobserver: QLab = 2.4 ± 7.5; TomTec30 = 1.2 ± 5.1; TomTec75 = 1.3 ± 4.5). Intervendor agreement between QLab and TomTec30 showed larger bias and wider limits of agreement (bias: QLab vs TomTec30: end-systolic volume [ESV] = 0.8% ± 23.6%; EDV = -2.2% ± 17.0%) with notable individual differences in small children. QLab and TomTec underestimated CMR values, with the highest agreement between CMR and QLab. CONCLUSIONS: RT3DE allows reproducible noninvasive assessment of LV volumes and function. However, intertechnique variability is relevant. Therefore, our software-specific percentiles, based on a large pediatric population, serve as a reference for both commonly used quantification programs.

Validation and Reference Values for Three-Dimensional Echocardiographic Right Ventricular Volumetry in Children: A Multicenter Study.

BACKGROUND: Functional assessment of the right ventricle using real-time three-dimensional echocardiography (RT3DE) has fundamental relevance in young patients with congenital heart disease. Reference values for the pediatric population are scarce. This multicenter study was designed to (1) validate new evaluation software for RT3DE and (2) establish pediatric reference values. METHODS: For validation, right ventricular (RV) end-diastolic volume (EDV) and end-systolic volume (ESV) were determined from real-time three-dimensional echocardiographic data sets of 38 subjects (n = 17 healthy individuals and n = 21 patients with congenital heart disease) using new dedicated evaluation software (RV-Function 2.0) and compared with cardiac magnetic resonance investigations of the same patient cohort. In a prospective multicenter design, 360 real-time three-dimensional echocardiographic data sets of healthy children (172 girls) were analyzed. To create reference centiles, the cohort was subdivided into group I (children <7 years of age, n = 136 [female and male]), group II (girls 7-18 years of age, n = 106), and group III (boys 7-18 years of age, n = 118). RESULTS: Using RT3DE, RV volumes were slightly higher than using cardiac magnetic resonance (EDV, 0.8 ± 5.8% [limits of agreement, -10.8% to 12.5%; r = 0.993]; ESV, 2.0 ± 13.1% [limits of agreement, -24.2% to 28.2%; r = 0.989). Reproducibility was promising (intraobserver variability, 3.9 ± 11.4% for EDV and -1.7 ± 13.4% for ESV [intraclass correlation coefficient range, 0.94-0.98]; interobserver variability, 1.9 ± 11.8% for EDV and -0.3 ± 22.8% for ESV [intraclass correlation coefficient range, 0.85-0.96]). Regarding functional parameters, no significant gender differences were found among children in group I. In contrast, children in groups II and III differed in RV volumes, dimensional parameters, and tricuspid annular plane systolic excursion (P < .005); the children did not differ in deformation parameters. Feasibility was 90%. CONCLUSIONS: RT3DE yields accurate and reproducible RV volumes. The calculated percentile curves may facilitate the clinical use of RT3DE to analyze RV function in children.

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.

High proportion of genetic cases in patients with advanced cardiomyopathy including a novel homozygous Plakophilin 2-gene mutation.

Cardiomyopathies might lead to end-stage heart disease with the requirement of drastic treatments like bridging up to transplant or heart transplantation. A not precisely known proportion of these diseases are genetically determined. We genotyped 43 index-patients (30 DCM, 10 ARVC, 3 RCM) with advanced or end stage cardiomyopathy using a gene panel which covered 46 known cardiomyopathy disease genes. Fifty-three variants with possible impact on disease in 33 patients were identified. Of these 27 (51%) were classified as likely pathogenic or pathogenic in the MYH7, MYL2, MYL3, NEXN, TNNC1, TNNI3, DES, LMNA, PKP2, PLN, RBM20, TTN, and CRYAB genes. Fifty-six percent (n = 24) of index-patients carried a likely pathogenic or pathogenic mutation. Of these 75% (n = 18) were familial and 25% (n = 6) sporadic cases. However, severe cardiomyopathy seemed to be not characterized by a specific mutation profile. Remarkably, we identified a novel homozygous PKP2-missense variant in a large consanguineous family with sudden death in early childhood and several members with heart transplantation in adolescent age.