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Aims Atrial fibrillation (AF) ablation protocols using energy delivery with very high power and short duration (vHPSD) have been introduced to improve lesion formation. This study reports procedural data of vHPSD ablation in AF patients and analyses characteristics of ablation-induced left atrial (LA) scar formation from cardiac magnetic resonance imaging (MRI). Methods and results Sixty consecutive patients undergoing index pulmonary vein isolation following our institutional Q4U-AF workflow were prospectively enrolled. Ablation was conducted using a contact force sensing catheter allowing for vHPSD ablation using a temperature-controlled ablation mode. Thirty patients underwent cardiac late gadolinium enhancement MRI of the LA 3 months after ablation to assess LA scar. Mean procedural duration was 66.5 ± 14.8 min. Mean ablation time was 4.7 ± 0.9 min with a mean number of 69.9 ± 14.2 applications. First-pass isolation was achieved in 51 patients (85%) for the right pulmonary veins (RPVs), in 37 patients (61.7%) for the left pulmonary veins (LPVs), and in 34 patients (56.7%) for both pulmonary veins (PVs). Magnetic resonance imaging at 3 months post-ablation demonstrated a mean scar width of 14.4 ± 2.6 mm around RPVs and 11.9 ± 1.9 mm at LPVs (P > 0.05). Complete PV encirclement was observed in 76.7% for RPVs, in 76.7% for LPVs, and in 66.7% for both PV pairs. During a mean follow-up of 4.7 ± 1.4 months, arrhythmia recurrence was observed in 3.3% of the patients. Conclusion Pulmonary vein isolation following a novel vHPSD workflow resulted in short procedure duration and high acute and mid-term efficacy. Magnetic resonance imaging demonstrated durable and transmural PV lesions with homogeneous and contiguous scar formation.

The clinical significance of collateral flow for the ventricular function of patients with univentricular hearts is often debated. This study evaluates the impact of collateral flow on respiration-dependent preload modification and diastolic function in Fontan patients assessed by systemic and pulmonary vein (PV) flow patterns.Real-time phase-contrast cardiovascular magnetic resonance was performed in the right upper PV, ascending aorta, superior, and inferior vena cava (IVC) in 21 Fontan patients and 11 healthy individuals. The patients' respiratory cycle was divided into 4 periods to generate respiratory-dependent stroke volumes (SVi). Conventional quantitative blood flow measurements were used to quantify and differentiate between low (group A) and high (group B) collateral flow.Group B showed significantly lower SVi IVC in inspiration, end-inspiration, expiration, and SVi ΔIVC compared with group A (23.6±4.8 mL/m2 to 33.4±8.0; P=0.005). PV flow resulted in a lower mean SVi PV (11.6±7.6 mL/m2, vs. 14.0±11.4 mL/m2) as well as a significantly lower peak systolic S-wave velocity (Smax) (P=0.005), S/D-ratio (Smax/peak diastolic wave velocity) (P=0.015), and shorter diastolic deceleration time (DTD; P=0.030; median DTD=134 ms) compared with group A (DTD=202 ms).This study demonstrates the incapability of Fontan patients to properly increase preload by inspiration in the presence of significant collateral flow. The results further show that collateral flow is associated with a volume-deprived ventricle and impaired diastolic function.

Left ventricular non-compaction (LVNC) describes the phenotypical phenomena characterized by the presence of excessive trabeculation of the left ventricle which forms a deep recess filled with blood. Considering the lack of a uniform definition of LVNC as well as the “golden standard” it is difficult to estimate the actual incidence of the disease, however, seems to be overdiagnosed, due to unspecific diagnostic criteria. The non-compacted myocardium may appear both as a disease representation or variant of the norm or as an adaptive phenomenon. This article covers different approaches to incidence, pathogenesis, diagnostics, and treatment of LVNC as well as recommendations for patients during follow-up.

Aims: The present study aims to evaluate magnetic-resonance-imaging (MRI)-assessed left atrial strain (LAS) and left atrial strain rate (LASR) as potential parameters for the diagnosis of cardiac amyloidosis (CA), the distinction of clinical subtypes and differentiation from other cardiomyopathies. Methods and results: LAS and LASR were assessed by MRI feature tracking in patients with biopsy-proven CA. LAS and LASR of patients with CA were compared to healthy subjects and patients with hypertrophic cardiomyopathy. LAS and LASR were also analyzed concerning differences between patients with transthyretin (ATTR) and light chain amyloidosis (AL). A total of 44 patients with biopsy-proven CA, 19 patients with hypertrophic cardiomyopathy and 24 healthy subjects were included. In 22 CA patients (50%), histological examination identified ATTR as CA subtype and AL in the remaining patients. No significant difference was observed for reservoir, conduit or booster LAS in patients with AL or ATTR. Reservoir LAS, conduit LAS and booster LAS were significantly reduced in patients with CA and HCM as compared to healthy subjects (p < 0.001). Reservoir LAS and booster LAS were significantly reduced in CA as compared to HCM patients (p < 0.001). A linear correlation was observed between LA global reservoir strain and LA-EF (p < 0.001, r = 0.5), conduit strain and global longitudinal LV strain (p < 0.001, r = 0.5), global booster strain rate and LA-EF (p < 0.001, r = 0.6) and between global booster strain rate and LA area at LVED (p < 0.0001, 0.5). Conclusions: LAS and LASR are severely impaired in patients with CA. The MRI-based assessment of LAS and LASR might allow non-invasive diagnosis and categorization of CA and its distinct differentiation from other hypertrophic phenotypes.

Left-atrial (LA) strain is the result of complex hemodynamics, increasingly assessed by feature-tracking cardiovascular magnetic resonance (CMR). We investigate the value of multi-parametric regression (MPR) analyses and the influence of the heart rate on LA-strain. As LA-strain data remains limited, CMR-quantified sex- and age-dependent normal values were derived. After following a health assessment questionnaire, 183 healthy volunteers (11-70 years, 97 females, median 32.9±28.3 years) were recruited for LA-strain assessment. LA volumetric data, left ventricular strain, transmitral and pulmonary venous blood flow parameters were utilized to create clusters for MPR analyses for all subjects and heart rate-specific subgroups (range: 60–75 beats-per-minute, N=106). In comparison to the total cohort, subgroups showed no gender differences (p>0.05) for LA reservoir, conduit and booster strains (all: 47.3±12.7%; 29.0±15.5%; 17.6±5.4%) and strain rates (all: 2.1±1.0 s−1; -2.9 ± 1.5 s−1; -2.3 ± 1.0 s−1). MPR analyses identified parameter clusters with large effect size (|R²|≥0.26) for reservoir-, conduit- and booster strain and corresponding active and passive cardiac functional parameters. Increased correlations for the subgroup were found. In contrast to previous studies, heart rate selected subgroups showed no gender differences in LA-strain. MPR analyses improve characterization of LA-strain at selected heart rates.

Purpose Quantitative blood flow measurements in thoracic vessels are dependent on the patient's respiration due to intrathoracic pressure changes. Several registration techniques for tracing the patient's breathing curve exist exploiting various physiological characteristics. In the presented study two registration techniques were investigated to estimate the time-shift between the associated respiration curves and the impact on respiration-dependent hemodynamic measures. Materials and methods Using flow-sensitive real-time magnetic resonance imaging (3.0 T, temporal resolution = 24–26 ms) data were acquired during a 13 s time-interval under normal physiological (no) and forced breathing (fo) in the ascending aorta (AAo) and inferior vena cava (IVC). Breathing curves were obtained by using (1) an abdominal placed respiratory belt (=standard, RB) and (2) by applying a self-developed edge-detection software (ED). Respiration curves were divided into four intervals (end-expiration, inspiration, end-inspiration and expiration) to generate respiration-dependent stroke volumes (SVs) and cardiac indices (CIs). Data were available from 12 healthy controls (16.2 ± 8.8 yrs) and 18 Fontan-patients (18.6 ± 7.1 yrs). Results Respiration curves acquired with RB differs from and are shifted compared to those obtained by ED (controls: average shift = 207 ± 168 ms, Fontan-patients: average shift = 106 ± 235 ms). This time-shift results in statistical significant differences in cardiac indices CIAAo,fo in controls (ΔCIAAo,fo: expiration: +0.16 L/min/m2, p = 0.018), in CIIVC,no in Fontan-patients (ΔCIIVC,no: end-expiration: +0.94 L/min/m2, p = 0.002 and end-inspiration: −1.04 L/min/m2, p = 0.017) and in CIIVC,fo in Fontan-patients (ΔCIIVC,fo: end-expiration: +1.31 L/min/m2, p = 0.009; inspiration: −2.26 L/min/m2, p = 0.008 and end-inspiration: −1.87 L/min/m2, p = 0.029). Conclusions A time-shift between both applied respiratory tracking techniques was observed resulting in significant differences in respiration-dependent CIs, which could influence the clinical decision-making.

Left-atrial (LA) strain is the result of complex hemodynamics, which may be better characterized using a multiparametric approach. Cardiovascular magnetic resonance (CMR) feature tracking was used to perform a comprehensive LA strain assessment of 183 enrolled healthy volunteers (11–70 years, 97 females, median 32.9 ± 28.3 years). Novel strain dependencies were assessed using multi-parametric regression (MPR) analyses. LA volumetric data, left ventricular strain, transmitral and pulmonary venous blood flow parameters were utilized to create clusters for MPR of all subjects and a heart rate controlled subgroup (pulse: 60–75/min, N = 106). The LA reservoir(r) and conduit(c) strains of the total cohort were significantly elevated (p ≤ 0.001) in women (r: 49.7 ± 12.9%, c: 32.0 ± 11.0%) compared to men (r: 42.9 ± 11.4%, c: 26.1 IQ 10.5%). In contrast, there were no gender-specific differences (p > 0.05) for subgroup LA reservoir, conduit and booster(b) strains (all, r: 47.3 ± 12.7%; c: 29.0 IQ 15.5%; b: 17.6 ± 5.4%) and strain rates (all, 2.1 IQ 1.0 s−1; − 2.9 IQ 1.5 s−1; − 2.3 IQ 1.0 s−1). MPR found large effect sizes (|R2|≥ 0.26) for correlations between strain and various cardiac functional parameters. Largest effect size was found for the association between LA conduit strain and LA indexed booster volume, LA total ejection fraction, left ventricular global radial strain and E-wave (|R2|= 0.437). In addition to providing normal values for sex-dependent LA strain and strain rate, no gender differences were found with modified heart rate. MPR analyses of LA strain/strain rate and various cardiac functional parameters revealed that heart rate control improved goodness-of-fit for the overall model.

Currently, little is known about the genetic background of restrictive cardiomyopathy (RCM). Herein, we screened an index patient with RCM in combination with atrial fibrillation using a next generation sequencing (NGS) approach and identified the heterozygous mutation DES-c.735G>C. As DES-c.735G>C affects the last base pair of exon-3, it is unknown whether putative missense or splice site mutations are caused. Therefore, we applied nanopore amplicon sequencing revealing the expression of a transcript without exon-3 in the explanted myocardial tissue of the index patient. Western blot analysis verified this finding at the protein level. In addition, we performed cell culture experiments revealing an abnormal cytoplasmic aggregation of the truncated desmin form (p.D214-E245del) but not of the missense variant (p.E245D). In conclusion, we show that DES-c.735G>C causes a splicing defect leading to exon-3 skipping of the DES gene. DES-c.735G>C can be classified as a pathogenic mutation associated with RCM and atrial fibrillation. In the future, this finding might have relevance for the genetic understanding of similar cases.

Despite the use of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT), diagnosis of a driveline infection in ventricular assist device (LVAD) recipients remains challenging. Our aim was to evaluate the potential of a baseline 18F-FDG PET/CT (prior to an infection) for the diagnosis of an LVAD-related infection. We retrospectively selected all LVAD recipients who had undergone two consecutive whole-body 18F-FDG PET/CT examinations between January 2010 and December 2016. PET/CT was analyzed qualitatively (uptake pattern) and semi-quantitatively (SUVmax and ∆SUVmax). SUVmax was measured and compared in five distinctive volumes of interest along the LVAD driveline. An SUVmax threshold was calculated. Final diagnosis was made by clinical examination, microbiological parameters, and molecular imaging. Thirty patients were enrolled (mean age 54 ± 12 years; 26 male). Mean difference in SUVmax for all five positions between the first and the second PET/CT along the driveline was significantly higher in patients with an LVAD-related infection (mean ∆SUVmax = 4.38 ± 1.44) compared to those without a driveline infection (mean ∆SUVmax = 0.03 ± 0.43), P

Assessment of left ventricular mass (LVM) is important in the evaluation of patients with congenital heart disease (CHD) and cardiac magnetic resonance imaging (CMR) is the gold standard. Recent software allows LVM calculation by real-time 3-dimensional echocardiography (RT3DE). We investigated the impact of different software analysis tools on LVM determination by CMR or RT3DE in a cohort of patients with heterogeneous left ventricular (LV) disease. 37 subjects (17 patients, mean age 18.7 y; 20 controls, mean age 13.2 y) underwent CMR and RT3DE. CMR LVM and RT3DE calculations were done using two different LV-analysis software packages for each modality: CMR i) customized software “CMR HDZ”, CMR ii) “CMR ISP”; RT3DE i) “Toshiba”, RT3DE ii) “Tomtec”, 4D LV-Analysis Version 3.1 (built 3.1.0.258661). Intra- and interobserver variabilities were calculated. Only RT3DE-derived LVM showed significant software-dependent differences. RT3DE-derived LVM (both softwares) was significantly higher than CMR-derived LVM (both softwares). The two different methods and four evaluation software packages for LVM assessment were well correlated with each other. Intra- and interobserver variability of LVM as assessed by each single modality or software was low. Despite software dependency and overestimation of RT3DE-assessed LVM by 5 to 10%, RT3DE still competes with the gold standard, CMR, even in patients with various forms of LV disease. The use of optimized software, especially for RT3DE, should improve the accuracy of LVM assessment, overcoming LVM overestimation.

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.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 (children7 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).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%.RT3DE yields accurate and reproducible RV volumes. The calculated percentile curves may facilitate the clinical use of RT3DE to analyze RV function in children.

Background Right ventricular volume quantification using real-time three-dimensional echocardiographic (RT3DE) imaging is limited by technical shortcomings of acquisition and quantification. In this study, a two-step approach was used to overcome these limitations. First, a modified acquisition technique for RT3DE imaging was applied, and second, a software tool using knowledge-based reconstruction (KBR) was used. The approach was validated against the gold standard, cardiac magnetic resonance (CMR) imaging, using CMR and RT3DE data sets from healthy children and from patients with congenital heart disease. Methods Sixty individuals (20 healthy persons, 40 with congenital heart defects; age range, 2.3–43.9 years; median age, 11.3 years) consecutively underwent investigation by CMR and RT3DE imaging. CMR data sets were first quantified by the method of disks (MOD) as the standard. Then CMR and RT3DE data sets were quantified using KBR software and compared with the MOD. Results CMR was more feasible than echocardiography (100% vs 88%). Compared with the MOD (CMR MOD ), there were trivial volume overestimations of KBR for CMR data (CMR KBR ), of end-diastolic volume (EDV) (−1.3 ± 8.6%, r = 0.984) and end-systolic volume (ESV) (−3.4 ± 13.3%, r = 0.985), resulting in a 0.7 ± 8.7% difference in ejection fraction (EF) ( r = 0.882). Comparing CMR MOD and RT3DE imaging, EDV (1.1 ± 7.4%, r = 0.990) and EF (0.8 ± 9.2%, r = 0.871) were slightly underestimated by RT3DE imaging, with a slight overestimation of ESV (−1.5 ± 13.3%, r = 0.977). Intraobserver variability was excellent for KBR of CMR and RT3DE data, with interclass coefficients of correlation of 0.995 and 0.997 for EDV, 0.995 and 0.994 for ESV, and 0.915 and 0.912 for EF. Interobserver variability provided intraclass correlation coefficients of 0.992 and 0.990 for EDV, 0.997 and 0.992 for ESV, and 0.953 and 0.933 for EF. The KBR analysis required a mean time of 5 min. Conclusions KBR is an accurate, versatile, and time-saving method for right ventricular three-dimensional volumetry; it shows excellent reproducibility for RT3DE and CMR data sets. These results suggest that this tool is clinically valuable.

Aims Blood flow rate quantification using two-dimensional phase-contrast MRI (PC-MRI) results in averaging of flow information due to long acquisition times precluding the examination of short-term effects. The aim of this study was to determine respiration-related flow rate variations by non-electrocardiographic triggered real-time phase-contrast MRI (PC-MRI). Methods and results Real-time PC-MRI was applied to study respiration-driven blood flow fluctuations in the ascending aorta (AAo), superior vena cava (SVC), and inferior vena cava (IVC) under normal and forced breathing in 33 healthy children and 10 Fontan patients. Respiration-dependent flow rates were virtually generated by dividing the respiration curve into four segments: expiration, end-expiration, inspiration, and end-inspiration. Whereas in volunteers aortic flow rate was elevated during end-expiration (5.6 ± 3.0%) and decreased during end-inspiration (−5.8 ± 3.5%) in relation to mean blood flow ( P < 0.05), highest flow was detected during inspiration in SVC (10.5 ± 14.1%) and IVC (22.5 ± 12.1%) and lowest flow during expiration (−11.6 ± 13.5%, −13.2 ± 14.1%, P < 0.05). Differences were increased under forced breathing in AAo (10.4 ± 5.5%, −7.4 ± 6.5%, P < 0.05) and SVC (40.0 ± 30.3%, −30.0 ± 19.2%, P < 0.05), whereas were unchanged in IVC (16.5 ± 23.6%, −13.7 ± 21.6%, P = n.s.). Regarding patients, respiratory-dependent flow rate variability was increased and had to be related to the patient's individual quality of Fontan circulation. Conclusion Real-time PC-MRI allows a physiological assessment of respiratory-related flow rate fluctuations in healthy subjects as well as in Fontan patients. Its capability for detection of short-term effects in clinical routine was demonstrated.

Background Evaluation of left atrial (LA) size and function is important in congenital and acquired pediatric cardiac disease. Real-time three-dimensional echocardiography (3DE) offers noninvasive assessment of cardiac volumes and phasic function independent of geometric assumptions. The aim of this prospective multicenter study was to establish pediatric reference values for LA 3DE volumes and phasic function based on a large cohort of healthy children. Methods LA data sets of 432 subjects (0 days-222 months) were analyzed prospectively using a vendor-independent software. LA volumes (maximal [Vmax], minimal [Vmin], and before atrial contraction) as well as phasic function (active and passive emptying fraction [EF]) were assessed. For volumes, sex-specific reference values, percentiles, and z-scores were calculated by the LMS method of Cole and Green. Results Absolute volumes increased with age and body surface area. Active EF and relative duration of atrial emptying tended to increase with increasing R-R intervals, while passive EF decreased. Reproducibility of volumes was very good (intra- and interobserver variability for Vmax and Vmin (mean bias ± SD, 0.1 ± 0.9 mL and 0.7 ± 2.8 mL). Volumes were well correlated with cardiac magnetic resonance measurements showing known underestimation of volumes by 3DE (mean bias ± SD, Vmax –14.2 ± 14 mL; Vmin –11.5 ± 10 mL). Conclusions Pediatric LA volumes and phasic function indices were reproducibly measured by 3DE. The provided pediatric reference values can be the basis for evaluation of the LA by 3DE and contribute to detection of LA dysfunction and follow-up of patients with congenital heart diseases.

BackgroundLeft 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.MethodsA 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).ResultsMaximal 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).ConclusionsPatients 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.

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.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.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 children7 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%.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.

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

Congenital heart defects such as coarctation or valvular aortic stenosis are followed by changes in left ventricular myocardial deformation mechanics induced by pressure overload.Echocardiography was performed in 37 patients (aged 0-27 years, 15 female) with coarctation (27) or valvular aortic stenosis (10) before and after interventional catheterization and compared with 37 body surface area/age-matched healthy children. Deformation was calculated by 2-dimensional strain speckle tracking.Stress gradients under provocation with orciprenaline in coarctation decreased from 51.8 +/- 20.0 mm Hg to 6.0 +/- 12.0 mm Hg (P.0001), and resting gradients in aortic stenoses decreased from 57.5 +/- 18.8 mm Hg to 25.5 +/- 14.0 mm Hg (P.0001) after intervention. Patients had an increased maximal torsion (tor(max): 16.7 +/- 6.7 deg vs 11.0 +/- 4.7 deg (controls; P.0001), which decreased significantly after therapy (11.8 +/- 4.9 deg, P.0001).Compensatory elevation of left ventricular tor(max) in children with moderate left ventricular pressure load changes rapidly after successful interventional treatment. tor(max) may be a valuable tool to assess cardiac unloading or indicate the need for interventional treatment.

Atypical left-to-right shunts at the level of the atrium in children such as sinus venosus atrial septal defects (ASDs) and partial anomalous pulmonary venous return (PAPVR) may be difficult to assess by transthoracic or transoesophageal echocardiography. Free-breathing cardiac MRI may be a powerful alternative.To assess the value of free-breathing cardiac MRI in the delineation of atypical ASDs in children.A total of 82 children (mean age 5.9 years, range 1.1-15.7 years) with suspected ASD and inconclusive transthoracic echocardiography underwent cardiac MRI under free-breathing, mostly sedated conditions. Phase-contrast MRI was used for defect visualization and shunt quantification, and multiphase inflow MR angiography for delineation of pulmonary/systemic venous connections.Of the 82 patients, 34 (41%) were diagnosed with atypical shunt lesions at the level of the atrium and 48 (59%) with simple secundum ASDs. No false-negative or false-positive findings were reported by MRI compared to cardiac catheterization and intraoperative findings. Superior sinus venosus ASD with partial anomalous PAPVR was present in 10 of the 82 children (12.2%), whereas 2 (2.4%) had a large posterior-inferior defect, 5 (6.1%) had isolated PAPVR, and 17 (20.7%) had multiple ASDs and/or associated vascular anomalies. Q(p)/Q(s) by phase-contrast MRI agreed well with oximetry values (mean difference 3%, limits of agreement +/-21-25%; Bland/Altman analysis).Free-breathing cardiac MRI under sedation allows reliable identification of atypical left-to-right shunt defects at the level of the atrium in children in whom transcatheter ASD closure is unsuitable, including delineation of pulmonary or systemic venous anomalies and shunt quantification.

To evaluate the diagnostic benefit of time-resolved CENTRA-keyhole contrast-enhanced cardiovascular magnetic resonance angiography (CE-CMRA) for improving arterial-venous separation of pulmonary vessels.Twenty-three patients (18 males; age = 58 +/- 11y) after radiofrequency pulmonary vein isolation to treat atrial fibrillation were examined using CENTRA-keyhole based multi-phase 3D CE-CMRA yielding 6 near-isotropic 3D datasets every 1.6 s (50-60 coronal partitions, 1.4 x 1.4 x 1.3 mm, SENSE-factor 3). Results were compared with conventional non-keyhole CE-CMRA (identical parameters, SENSE-factor 2).Data acquisition was accelerated by a speedup factor of approximately 9 compared with the reference CE-CMRA (SENSE 1.5*, keyhole 6*). No pulmonary venous stenoses were detected by either method, overall pulmonary venous diameters were 17.1 +/- 3.6 mm. Applying Bland-Altman analysis, vessel diameters differed by a mean of 0.1 mm + 2.1 mm/-2.0 mm (mean +/- 2 SD), indicating close agreement between both techniques. Interobserver variability was higher for CENTRA-keyhole (mean = 0.1 mm; mean +/- 2 SD: +2.5 mm/-2.3 mm) compared to conventional technique (0.0 mm; +1.6 mm/-1.5 mm), corresponding to a percentual deviation (mean +/- 2 SD) of the mean diameter of approximately +/- 15% (keyhole CE-CMRA) and +/- 10% (conventional CE-CMRA), respectively. Using keyhole-based time-resolved CE-CMRA, the contrast between pulmonary veins versus aorta/pulmonary artery was significantly increased (p0.05), which improved vessel depiction. In 12 cases, the contrast bolus arrival was delayed in one of the pulmonary veins by 1 dynamic frame (= 1.6 seconds); in 7 cases by 2 frames (= 3.2 seconds) and in 1 subject by 3 frames (= 4.8 seconds). The bolus usually appeared first in the upper right pulmonary vein whereas a delay occurred most often in the lower left pulmonary vein.Conventional CE-CMRA may be advantageous for accurate vessel size measures as evidenced by superior interobserver reproducibility in this study. Multi-dynamic CE-CMRA using CENTRA-keyhole with SENSE, however, allows for improved arterio-venous separation of pulmonary vessels and additional dynamical information on pulmonary venous perfusion, while maintaining high spatial resolution. Exact bolus timing is no longer needed.

Background— Operator-independent isotropic 3D MRI may greatly simplify the assessment of complex morphology in congenital heart disease. We sought to evaluate the reliability of this new approach. Methods and Results— In 31 adolescent and adult patients (age, 6 to 42 years; median, 16 years) with congenital heart disease, cardiac morphology was determined with free-breathing (navigator-gated), isotropic, 3D steady-state free-precession (3D SSFP) MRI and independently evaluated by 2 observers. Cardiac diagnoses and multiple distance measurements were compared with conventional MR reference sequences (ie, spin-echo, cine gradient-echo, contrast-enhanced MR angiography) and with echocardiography/cine cardioangiography or surgery. Of the 31 patients, 24 had native congenital heart defects or residual defects after repair that warranted immediate treatment. None of these defects was missed by 3D SSFP. Novel diagnostic issues were discovered in 4 of 31 patients (coronary anomalies, n=3; left juxtaposition of the right atrial appendage in double-outlet right ventricle and transposition of the great arteries, 1). For sizes of valves and vessels, we found minor mean differences of −1.1 to 1.6 mm, with SD ranging from 1.2 to 2.9 mm, demonstrating overall good agreement with standard MRI (Bland-Altman analysis). Interobserver variability of 3D SSFP distance measures was low; mean differences ranged from −1.5 to 1.0 mm, and SD ranged from 0.8 to 2.5 mm. Scatter was lower for extracardiac than intracardiac measures. Conclusions— In adolescents and adults, isotropic 3D SSFP MRI allows reliable assessment of complex cardiac morphology. Distance measurements are accurate and reproducible. Thus, a single operator-independent acquisition may substitute for conventional 2D MRI sequences to accelerate and simplify MR scanning in congenital heart disease.

Background— Parallel imaging by sensitivity encoding (SENSE) may considerably reduce scan time in MRI. For rapid flow quantification in children with congenital heart disease, we evaluated phase-contrast MRI (PC-MRI) techniques combined with SENSE. Methods and Results— In 22 pediatric patients (mean age, 7.2±6.2 years) with cardiac left-to-right shunt, blood flow rate in the pulmonary artery (Q p ) and ascending aorta (Q s ) and flow ratio Q p /Q s were determined by PC-MRI with SENSE reduction-factor 2 and 3 (SF-2 and SF-3). Additionally, we used PC-MRI with higher spatial in-plane resolution (1.6×2.1 versus 2.3×3.1 mm) with and without SF-3. Results were compared with a recently validated standard PC-MRI protocol and tested in vitro using a pulsatile flow phantom. Reduction of signal averages from 2 to 1 and application of SENSE accelerated flow measurements by a factor of 3.5 (5.2) using PC-MRI with SF-2 (SF-3) compared with standard PC-MRI. For blood flow rate through the pulmonary artery and aorta, as well as for the Q p /Q s ratio we found negligible differences of ±3%, lower limits of agreement (mean±2 SD) of −7% to −18%, and upper limits of agreement (mean±2 SD) of +3 to +24%, demonstrating good agreement with standard PC-MRI. Mean Q p /Q s ratio by standard PC-MRI was 1.69±0.45 (range, 1.27 to 2.79). Interobserver variability was low, and high accuracy was confirmed in vitro for all protocols. Conclusions— PC-MRI for flow quantitation may be combined with SENSE to achieve a substantive reduction of scanning time. In children with left-to-right shunt, Q p /Q s quantification is possible by PC-MRI+SF-3 in

Background Reference values for left ventricular mass (LVM) are important echocardiographic tools for the follow-up of pediatric patients with cardiac disease. Cardiac magnetic resonance (CMR) imaging is currently regarded as the gold standard. The aims of this study were to validate LVM calculated using real-time three-dimensional echocardiography (RT3DE) and to establish pediatric reference values. Methods For validation, 40 subjects (20 patients) consecutively underwent CMR (3-T TX Achieva, 25 cardiac phases/slice) and RT3DE (iE33 or Vivid E9, four subvolumes) in a single-center approach. The quantification of CMR data by the disk summation method as standard (mean LVM, 84.2 ± 53 g; range, 17.7–231.7 g) was compared with RT3DE. In a multicenter prospective design, 434 healthy children were investigated using standard software (LV-Analysis version 3.1). Results In comparison with CMR, RT3DE provided a slight overestimation of LVM of only 2.5 ± 11.3% (r = 0.990, intraclass correlation coefficient = 0.995), and there was low intraobserver (mean, 0.9 ± 7.1%; scatter, 13.2% to −15.0%; r = 0.996; intraclass correlation coefficient = 0.998) and interobserver (mean, 1.5 ± 9.3%; scatter, 17.2% to −20.1%; r = 0.993; intraclass correlation coefficient = 0.996) variability. Feasibility of the multicenter approach was 76%, resulting in 332 healthy children (median age, 10.0 years; range, 0–18 years; group I range, 0–6 years; group II range, 7–18 years) with data sets providing adequate image quality. LVM was correlated with sex (group II), age (r = 0.901), height (r = 0.881), weight (r = 0.876), and body surface area (r = 0.898). Unisex percentiles for 0 to 6 years of age and separated according to gender from 7 to 18 years of age were established. Mean calculation time for RT3DE was Conclusions In children, LVM calculation presuming excellent real-time three-dimensional echocardiographic data sets is accurate, quick, and reproducible. The percentiles provided are based on a large sample size and may be useful for clinical practice.

Aim Left ventricular rotation is an interesting mechanism to investigate patients with heart disease. In children, reference values have to be defined prior to assess pathology. Methods and results One hundred and seventy-four healthy individuals (0–20 years) were investigated by two-dimensional speckle tracking echocardiography, percentiles were created addressing the amount and time-to-peak values (TTP) of rotational parameters normalized to percentage of cardiac cycle (cc). Patients with right ventricular (RV) pacemaker stimulation were integrated into percentiles describing their rotational delay. Feasibility was 87.4% in healthy individuals (8.5 ± 6.2 years), 42 patients (13.0 ± 6.6 years, mean RV-stimulation time: 6.1 ± 4.3 years) were enrolled. Apical rotation (Rotap) varied and was higher than basal rotation (Rotbas) throughout all ages. Peak torsion (Tormax) normalized to left ventricle (LV) length (Tormaxi) was elevated in early childhood and decreased until adulthood. TTP values revealed greater dispersion between apical and basal rotation at younger age and a decrease during maturation. Patients with RV pacing had decreased Tormax (10.0 ± 6.0 vs. 13.7 ± 6.6°, P < 0.05), Rotap (6.7 ± 4.8 vs. 9.3 ± 5.7°, P < 0.05) and Rotbas (−3.3 ± 2.6 vs. −4.5 ± 2.7°, P < 0.05). Patients with impaired ejection fraction (EF) had abnormal delays between Rotap and Rotbas. Conclusions Percentile illustrations of LV rotation reveal a high amount and dispersion of Rotap and Tormaxi in young children as well as a higher rotational delay compared with older ages. Abnormal delays in RV pacing are associated with reduced EF.

Objective: To compare the modalities 3D-echocardiography (RT3DE) and cardiac magnetic resonance as well as semiautomatic non-model-based and model-based quantification software (SWP-MRI and SWT-MRI) regarding accuracy and agreement of left ventricular functional indices. Methods: 9 asymmetrically shaped gel phantoms (range: 20-350ml), 24 healthy children (age=11.4±3.3y) and 11 patients with abnormally shaped left ventricles (22.0±17.0y) were prospectively investigated. 3D-echocardiography was performed using a Vivid 7 ultrasound machine (V3 matrix transducer); postprocessing was done with a model-based analysis strategy (SWT-echo). CMR datasets were obtained using a multi-slice multi-phase steady‑state-free-precision acquisition (TR/TE/flip=2.8msecs/1.4msecs/60°) with a 1.5T MR system. Volume quantification was done using the same model-based software for CMR as well as non model-based software based on the summation of discs method. Agreement of EDV, ESV and EF between SWT-echo, SWP-mri vs. SWT-mri was determined by Bland Altman analysis. Results: Phantom study revealed high accuracy (

AimsTo evaluate the role of torsion in hypertrophic cardiomyopathy in children.MethodsA 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).ResultsIn 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).ConclusionsIn 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.