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In computed tomography (CT) evaluation prior to transcatheter aortic valve implantation area- and perimeter-based calculation of the aortic annulus diameter, the so-called effective annulus diameter (ED), is the preferred parameter for decision making regarding prosthesis sizes. Currently, it is unclear how relevant the differences between the two methods of measurement are and how they are influenced by the cardiac cycle. The aim of this study was to compare area- and perimeter-based measurements in computed tomography derived aortic annulus sizing. A total of 60 patients who underwent evaluation for transcatheter aortic valve implantation were included in this study. All patients received pre-procedural ECG gated CT. The aortic annulus area and perimeter were measured and the derived ED compared using parametric statistics and Bland and Altman analysis. The mean patient age was 80.2 ± 4 years. Systolic aortic annulus area and perimeter were higher compared to diastolic results (mean difference area 12.8 ± 24 mm and perimeter 0.72 ± 1 mm; p = 0.009-0.068). Both the area- and perimeter-based ED had a good agreement within two standard deviations for systolic and diastolic measurements. Effective diameter measurements derived from the area were significantly smaller compared to perimeter-based measurements (mean difference: systolic 0.72 ± 0.3 mm and diastolic 0.81 ± 0.4 mm; p < 0.001). While the area-based ED was significantly influenced by the cardiac cycle with a mean difference of 0.4 ± 0.6 mm ( p = 0.009), no significant difference was found for the perimeter-based ED (mean difference: 0.2 ± 0.4; p = 0.07). For patients undergoing CT evaluation prior to transcatheter aortic valve implantation, the perimeter-based effective annulus diameter provides a reliable parameter for annulus sizing without significant affection by the cardiac cycle and therefore facilitates annulus measurements with a single heart phase. However, perimeter-based diameters of the annulus are significantly larger than area-based diameters. [ABSTRACT FROM AUTHOR]

Purpose:  To utilize 4 D flow MRI to acquire normal values of "conventional 2 D flow MRI parameters" in healthy volunteers in order to replace multiple single 2 D flow measurements with a single 4 D flow acquisition., Materials and Methods:  A kt-GRAPPA accelerated 4 D flow sequence was used. Flow volumes were assessed by forward (FFV), backward (BFV), and net flow volumes (NFV) [ml/heartbeat] and flow velocities by axial (VAX) and absolute velocity (VABS) [m/s] in 116 volunteers (58 females, 43 ± 13 years). The aortic regurgitant fraction (RF) was calculated., Results:  The sex-neutral mean FFV, BFV, NFV, and RF in the ascending aorta were 93.5 ± 14.8, 3.6 ± 2.8, 89.9 ± 0.6 ml/heartbeat, and 3.9 ± 2.9 %, respectively. Significantly higher values were seen in males regarding FFV, BFV, NFV and RF, but there was no sex dependency regarding VAX and VABS. The mean maximum VAX was lower (1.01 ± 0.31 m/s) than VABS (1.23 ± 0.35 m/s). We were able to determine normal ranges for all intended parameters., Conclusion:  This study provides quantitative 4 D flow-derived thoracic aortic normal values of 2 D flow parameters in healthy volunteers. FFV, BFV, NFV, and VAX did not differ significantly from single 2 D flow acquisitions and could therefore replace time-consuming multiple single 2 D flow acquisitions. VABS should not be used interchangeably., Key Points:   · 4 D flow MRI can be used to replace 2 D flow MRI measurements.. · The parameter absolute velocities can be assessed by 4 D flow MRI.. · There are sex-dependent differences regarding forward, backward, net aortic blood flow and the aortic valve regurgitant fraction.., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Background: The rotational direction (RD) of helical blood flow can be classified as either a clockwise (RD + ) or counter-clockwise (RD - ) flow. We hypothesized that this simple classification might not be sufficient for analysis in vivo and a simultaneous existence of RD +/- may occur. We utilized volumetric velocity-sensitive cardiovascular magnetic resonance imaging (4D flow MRI) to analyze rotational blood flow in the thoracic aorta., Methods: Forty volunteers (22 females; mean age, 41±16 years) and seventeen patients with bicuspid aortic valves (BAVs) (9 females; mean age, 42±14 years) were prospectively included. The RDs and the calculation of the rotating blood volumes (RBVs) in the thoracic aorta were performed using a pathline-projection strategy., Results: We could confirm a mainly clockwise RD in the ascending, descending aorta and in the aortic arch. Furthermore, we found a simultaneous existence of RD + /RD - . The RD +/- -volume in the ascending aorta was significantly higher in BAV patients, the mean RD + /RD - percentage was approximately 80%/20% vs. 60%/40% in volunteers (P<0.01). The maximum RBV always occurred during systole. There was significantly more clockwise than counter-clockwise rotational flow in the ascending aorta (P<0.01) and the aortic arch (P<0.01), but no significant differences in the descending aorta (P=0.48)., Conclusions: A simultaneous occurrence of RD + /RD - indicates that a simple categorization in either of both is insufficient to describe blood flow in vivo . Rotational flow in the ascending aorta and in the aortic arch differs significantly from flow in the descending aorta. BAV patients show significantly more clockwise rotating volume in the ascending aorta compared to healthy volunteers., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-23-183/coif). AA was supported by an ESOR/ESCR 2019 cardiac fellowship. The other authors have no conflicts of interest to declare., (2023 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

Aim This completely revised interdisciplinary S2k-guideline on the diagnosis, therapy, and follow-up care of female patients with urinary incontinence (AWMF registry number: 015-091) was published in December 2021. This guideline combines and summarizes earlier guidelines such as "Female stress urinary incontinence," "Female urge incontinence" and "Use of Ultrasonography in Urogynecological Diagnostics" for the first time. The guideline was coordinated by the German Society for Gynecology and Obstetrics (Deutsche Gesellschaft für Gynäkologie und Geburtshilfe, DGGG) and the Working Group for Urogynecology and Plastic Pelvic Floor Reconstruction (Arbeitsgemeinschaft für Urogynäkologie und plastische Beckenbodenrekonstruktion e. V., AGUB). Methods This S2k-guideline was developed using a structured consensus process involving representative members from different medical specialties and was commissioned by the Guidelines Commission of the DGGG, OEGGG and SGGG. The guideline is based on the current version of the guideline "Urinary Incontinence in Adults" published by the European Association of Urology (EAU). Country-specific items associated with the respective healthcare systems in Germany, Austria and Switzerland were also incorporated. Recommendations The short version of this guideline consists of recommendations and statements on the surgical treatment of female patients with stress urinary incontinence and urge incontinence. Specific solutions for the diagnostic workup and treatment of uncomplicated and complicated urinary incontinence are discussed. The diagnostics and surgical treatment of iatrogenic urogenital fistula are presented., Competing Interests: Conflict of Interest The conflicts of interest of the authors are listed in the long version of the guideline ( https://register.awmf.org/de/leitlinien/detail/015-091 )./ Die Interessenkonflikte der Autoren sind in der Langfassung der Leitlinie ( https://register.awmf.org/de/leitlinien/detail/015-091 ) aufgelistet., (Thieme. All rights reserved.)

Aim This completely revised interdisciplinary S2k-guideline on the diagnosis, therapy, and follow-up care of female patients with urinary incontinence (AWMF registry number: 015-091) was published in December 2021. This guideline combines and summarizes earlier guidelines such as "Female stress urinary incontinence," "Female urge incontinence" and "Use of Ultrasonography in Urogynecological Diagnostics" for the first time. The guideline was coordinated by the German Society for Gynecology and Obstetrics (Deutsche Gesellschaft für Gynäkologie und Geburtshilfe, DGGG) and the Working Group for Urogynecology and Plastic Pelvic Floor Reconstruction (Arbeitsgemeinschaft für Urogynäkologie und plastische Beckenbodenrekonstruktion e. V., AGUB). Methods This S2k-guideline was developed using a structured consensus process involving representative members from different medical specialties and was commissioned by the Guidelines Commission of the DGGG, OEGGG and SGGG. The guideline is based on the current version of the guideline "Urinary Incontinence in Adults" published by the European Association of Urology (EAU). Country-specific items associated with the respective healthcare systems in Germany, Austria and Switzerland were also incorporated. Recommendations The short version of this guideline consists of recommendations and statements on the epidemiology, etiology, classification, symptoms, diagnostics, and treatment of female patients with urinary incontinence. Specific solutions for the diagnostic workup and appropriate conservative and medical therapies for uncomplicated and complication urinary incontinence are discussed., Competing Interests: Conflict of Interest The conflicts of interest of all the authors are listed in the long version of the guideline ( https://register.awmf.org/de/leitlinien/detail/015-091 )./ Die Interessenkonflikte der Autoren sind in der Langfassung der Leitlinie ( https://register.awmf.org/de/leitlinien/detail/015-091 ) aufgelistet., (Thieme. All rights reserved.)

Objectives: 4D flow MRI enables quantitative assessment of helical flow. We sought to generate normal values and elucidate changes of helical flow (duration, volume, length, velocities and rotational direction) and flow jet (displacement, flow angle) as well as wall shear stress (WSS)., Methods: We assessed the temporal helical existence (TH EX ), maximum helical volume (HV max ), accumulated helical volume (HV acc ), accumulated helical volume length (HVL acc ), maximum forward velocity (maxV for ), maximum circumferential velocity (maxV circ ), rotational direction (RD) and maximum wall shear stress (WSS) as reported elsewhere using the software tool Bloodline in 86 healthy volunteers (46 females, mean age 41 ± 13 years)., Results: WSS decreased by 42.1% and maxV for by 55.7% across age. There was no link between age and gender regarding the other parameters., Conclusion: This study provides age-dependent normal values regarding WSS and maxV for and age- and gender-independent normal values regarding TH EX , HV max , HV acc , HVL acc , RD and max V circ ., Key Points: • 4D flow provides numerous new parameters; therefore, normal values are mandatory. • Wall shear stress decreases over age. • Maximum helical forward velocity decreases over age., (© 2022. The Author(s).)

Background: Pathophysiological differences in relief of pulmonary stenosis (PS) as opposed to pulmonary regurgitation (PR) by percutaneous pulmonary valve implantation (PPVI) remain elusive, but might impact current assessment of procedural success and ultimately indications., Methods: Invasive pressure measurements, cardiac magnetic resonance imaging and cardiopulmonary exercise testing were performed before pre-stenting (BMS), after BMS and after PPVI in patients with either PS or PR., Results: In PS (n = 14), BMS reduced the right ventricular (RV) to systemic pressure ratio (0.8 ± 0.2 vs. 0.4 ± 0.1%; p < .01), improved RF EF (53 ± 14 vs. 59 ± 12%; p = .01) but introduced free PR (PR fraction post 39 ± 12%; p < .01) with no changes in effective RV stroke volume (SV). PPVI eliminated PR (PR fraction 5 ± 3%; p < .01) and improved effective RV SV (p < .01) with no changes in RV EF (p = .47). Peak VO2 improved significantly after BMS, with no changes following PPVI (26 ± 9 vs. 30 ± 11 vs. 31 ± 10 ml/kg*min). In PR (n = 14), BMS exaggerated PR (PR fraction post 47 ± 10) with reduction in effective RV SV (pre 43 ± 9 vs. post 38 ± 8 ml/m 2 ; p = .01), which improved after PPVI (post PPVI 49 ± 9 ml/m 2 ; p < .01), secondary to elimination of PR (PR fraction 5 ± 4%; p < .01). RV EF (pre 53 ± 11 vs. post 53 ± 9 vs. post PPVI 50 ± 9%) and Peak VO2 (pre 22 ± 7 vs. post 21 ± 7 vs. post PPVI 23 ± 7 ml/kg*min) remained unchanged., Conclusions: Exercise capacity in patients with right ventricular outflow tract dysfunction is primarily afterload-dependent., (Copyright © 2020 Elsevier B.V. All rights reserved.)

4D flow MRI enables quantitative assessment of helical flow. Current methods are susceptible to noise. To evaluate helical flow patterns in healthy volunteers and patients with bicuspid aortic valves (BAV) at 1.5 T and 3 T using pressure-based helix-extraction in 4D flow MRI. Two intraindividual 4D flow MRI examinations were performed at 1.5 T and 3 T in ten healthy volunteers (5 females, 32 ± 3 years) and 2 patients with BAV using different acceleration techniques (kt-GRAPPA and centra). Several new quantitative parameters for the evaluation of volumes [ml], lengths [mm] as well as temporal parameters [ms] of helical flow were introduced and analyzed using the software tool Bloodline. We found good correlations between measurements in volunteers at 1.5 T and 3 T regarding helical flow volumes (R = 0.98) and temporal existence (R = 0.99) of helices in the ascending aorta. Furthermore, we found significantly larger (11.7 vs. 77.6 ml) and longer lasting (317 vs. 769 ms) helices in patients with BAV than in volunteers. The assessed parameters do not depend on the magnetic field strength used for the acquisition. The technique of pressure-based extraction of 4D flow MRI pattern is suitable for differentiation of normal and pathological flow.

To compare contrast-enhanced magnetic resonance angiography (ceMRA) and 3D steady-state free precession (SSFP) during systole and diastole for assessment of the right ventricle outflow tract (RVOT) in patients considered for percutaneous pulmonary valve implantation (PPVI) after tetralogy of Fallot (TOF) repair. We retrospectively evaluated 89 patients (male: 45, mean age 19 ± 8 years), who underwent cardiac-MRI after surgical TOF-repair. Datasets covering the whole heart in systole and diastole were acquired using ECG-gated 3D SSFP and non-gated ceMRA. Measurements were performed in SSFP-sequences and in ceMRA in the narrowest region of the RVOT to obtain the minimum, maximum and effective diameter. Invasive balloon sizing as the gold standard was available in 12 patients. The minimum diameter in diastolic SSFP, systolic SSFP and ceMRA were 21.4 mm (± 6.1 mm), 22.6 mm (± 6.2 mm) and 22.6 mm (± 6.0 mm), respectively. Maximum diameter was 29.9 mm (± 9.5 mm), 30.0 mm (± 7.0 mm) and 28.8 mm (± 8.1 mm) respectively. The effective diameter was 23.2 mm (± 5.7 mm), 27.4 mm (± 6.7 mm) and 24.4 mm (± 6.2 mm), differing significantly between diastole and systole (p < 0.0001). Measurements in ECG-gated SSFP showed a better inter- and intraobserver variability compared to measurements in non-ECG-gated ceMRA. Comparing invasive balloon sizing with our analysis, we found the highest correlation coefficients for the maximum and effective diameter measured in systolic SSFP (R = 0.99 respectively). ECG-gated 3D SSFP enables the identification and characterization of a potential landing zone for PPVI. The maximum and effective systolic diameter allow precise sizing for PPVI. Patients with TOF-repair could benefit from cardiac MRI before PPVI.

Objectives: To assess the incidence of acute adverse events (AAEs) in gadolinium-enhanced cardiac magnetic resonance (CMR) imaging., Methods: Gadolinium-based contrast agent (GBCA)-enhanced CMR data from the multinational, multicenter European Society of Cardiovascular Radiology MRCT Registry was included. AAE severity was classified according to the American College of Radiology Manual on Contrast Media (mild, moderate, severe). Multivariable generalized linear mixed effect models were used to assess the likelihood of AAEs in various GBCA, adjusting for pharmacological stressor, main indications (i.e., suspected or known coronary artery disease or myocarditis), age, sex, and submitting center as a random effect., Results: In the study population of 72,839 GBCA-enhanced CMRs, a total of 260 AAEs were reported (0.36%), with a minority of severe AAEs (n = 24, 0.033%). Allergic-like AAEs were less likely than physiologic AAEs (29% versus 71%). Patients without pharmacological stress imaging had a lower AAE rate (0.22%) compared to stress imaging (0.75%), with the highest AAE rates for regadenoson (2.95%). AAE rates also varied by GBCA subtype (overall p < 0.001). There was significant interaction between GBCA and pharmacological stressor (interaction p = 0.025), with AAE rates ranging between 0 and 10% for certain GBCA/stressor combinations. There was further marginal evidence that higher GBCA volume was associated with higher AAE incidence (OR = 1.02, p = 0.05)., Conclusion: GBCA-enhanced CMR imaging demonstrates low AAE rates comparable to those of other body regions. AAE likelihood correlates with GBCA subtype, pharmacological stressor, and imaging indication. Intravenous fluid administration in patients with cardiac impairment might contribute to these findings., Key Points: • Acute adverse event rates in cardiac magnetic resonance (CMR) imaging with gadolinium-based contrast agents (GBCAs) are low (0.36%), especially for severe adverse events (0.033%). • Mild and moderate adverse events are more frequent during stress CMR imaging. • Physiologic AAEs are more common than allergic AAEs in CMR imaging.

To compare two broadly used 4D-flow- with a 2D-flow-sequence in healthy volunteers, regarding absolute flow parameters, image quality (IQ), and eddy current correction (ECC). Forty volunteers (42 ± 11.8 years, 22 females) were examined with a 3T scanner. Thoracic aortic flow was assessed using a 3D-T2w-SPACE-STIR-sequence for morphology and two accelerated 4D-flow sequences for comparison, one with k-t undersampling and one with standard GRAPPA parallel-imaging. 2D-flow was used as reference standard. The custom-made software tool Bloodline enabled flow measurements for all analyses at the same location. Quantitative flow analyses were performed with and without ECC. One reader assessed pathline IQ (IQ-PATH) and occurrence of motion artefacts (IQ-ART) on a 3-point grading scale, the higher the better. k-t GRAPPA allowed a significant mean scan time reduction of 46% (17:56 ± 5:26 min vs. 10:40 ± 3:15 min) and provided significantly fewer motion artefacts than standard GRAPPA (IQ-ART 1.57 ± 0.55 vs. 0.84 ± 0.48; p < 0.001). Neither 4D-flow sequence significantly differed in flow volume nor peak velocity results with or without ECC. Nevertheless, the correlation between both 4D-flow sequences and 2D-flow was better with ECC; the k-t GRAPPA sequence performed best (R = 0.96 vs. 0.90). k-t GRAPPA 4D-flow was not inferior to a standard GRAPPA-sequence, showed fewer artefacts, comparable IQ and was almost two-fold faster.

Background: Prenatal risk stratification of women with previous cesarean section (CS) by ultrasound thickness measurement of the lower uterine segment (LUS) is challenging. There is a wide range of proposed cutoff values and a valuable algorithm for selection before birth is not available. Using 3 T magnetic resonance imaging (MRI), we aimed to identify possible shortcomings of the current protocols used for birth selection after CS. Therefore, we evaluated anatomic and morphologic differences of the LUS and its thickness in patients with CS and those without. Possible impact factors on LUS thickness were studied., Methods: We retrospectively analyzed 3 T MRI scans of 164 pregnant women in their second or third trimester, with (patient group, n = 60) and without previous CS (control group, n = 104). Sagittal T2-weighted images were studied. Normal findings of the LUS in MRI, reliability of MRI measurements, as well as factors influencing LUS thickness were assessed. MRI findings were compared to intraoperative findings., Results: MRI provided good intra- (ICC 0.872) and fair inter-rater reliability (ICC 0.643). The relationship of the LUS and the cesarean scar to the surrounding anatomical structures and also its morphology varied strongly in patients and controls. Scar identification was possible in only 9/60 (15.0%) patients. The LUS was thinner in patients (1.9 ± 0.7 mm) than in controls (2.7 ± 1.3 mm). An LUS thinning up to 1 mm was observed in 23% of women without a previous CS and in 34% of women with normal intraoperative findings. Suspicion of a uterine dehiscence (LUS thickness < 1 mm) was only found in the patient group (5/59 (8.5%)) and was intraoperatively confirmed. In controls, LUS thickness was influenced by fetal weight, gestational age and amniotic fluid amounts., Conclusion: Variability in anatomy, thickness and morphology seem to limit common prenatal LUS imaging diagnostics. Therefore, we consider that diagnostic protocols must be re-evaluated and imaging should be adjusted to the individual patient conditions. Due to its independency of ultrasound limitations, an additional MRI might be useful for altered anatomy and impaired ultrasound conditions. An LUS thinning up to 1 mm might be a normal finding and should be further investigated as reference value.

Background: Four-dimensional (4D) flow magnetic resonance imaging (MRI) sequences with advanced parallel imaging have the potential to reduce scan time with equivalent image quality and accuracy compared with standard two-dimensional (2D) flow MRI. We compared 4D flow to standard 2D flow sequences using a constant and pulsatile flow phantom at 3 T., Methods: Two accelerated 4D flow sequences (GRAPPA2 and k-t-GRAPPA5) were evaluated regarding the concordance of flow volumes, flow velocities, and reproducibility as well as dependency on measuring plane and velocity encoding (V enc ). The calculated flow volumes and peak velocities of the phantom were used as reference standard. Flow analysis was performed using the custom-made software "Bloodline"., Results: No significant differences in flow volume were found between the 2D, both 4D flow MRI sequences, and the pump reference (p = 0.994) or flow velocities (p = 0.998) in continuous and pulsatile flow. An excellent correlation (R = 0.99-1.0) with a reference standard and excellent reproducibility of measurements (R = 0.99) was achieved for all sequences. A V enc overestimated by up to two times had no impact on flow measurements. However, misaligned measuring planes led to an increasing underestimation of flow volume and mean velocity in 2D flow accuracy, while both 4D flow measurements were not affected. Scan time was significantly shorter for k-t-GRAPPA5 (1:54 ± 0:01 min, mean ± standard deviation) compared to GRAPPA2 (3:56 ± 0:02 min) (p = 0.002)., Conclusions: Both 4D flow sequences demonstrated equal agreement with 2D flow measurements, without impact of V enc overestimation and plane misalignment. The highly accelerated k-t-GRAPPA5 sequence yielded results similar to those of GRAPPA2.

Purpose: Uterine rupture during labor is a rare but life-threatening complication after previous cesarean section (CS). Prenatal risk is assessed using ultrasound thickness measurement of the lower uterine segment (LUS). Due to inhomogeneous study results, however, clinical obstetrics still lacks for standard protocols and reliable reference values. As 3 T magnetic resonance imaging (MRI) has not yet been sufficiently studied regarding LUS diagnostics after previous CS, we sought to evaluate its feasibility focusing on thickness measurements and typical characteristics of the CS-scar region in comparison to ultrasound and the intraoperative status., Methods: In this prospective study, 25 asymptomatic patients with one previous CS and inconspicuous ultrasound findings were included. An additional 3 T MRI with either a T2-weighted Turbo-Spin-Echo or a Half Fourier-Acquired-Single-shot-Turbo-spin-Echo sequence in a sagittal orientation was performed. We analyzed categorical image quality, inter- and intra-rater reliability as well as anatomy, morphology and thickness of the LUS. Results were compared to ultrasound and intraoperative findings., Results: MRI provided good to excellent image quality in all patients. The imaged structures presented with a high variability in anatomy and morphology. Image characteristics indicating the uterine scar were only found in 11/25 (44%) patients. LUS thickness measurements with MRI showed good inter- and intra-rater reliability but poor agreement with ultrasound., Conclusions: MRI is appropriate for additional LUS diagnostics in patients with previous CS. The strong individual variability of LUS-anatomy and morphology might explain the difficulties in establishing uniform diagnostic standards after CS.

Purpose: Dilatation of the thoracic aorta is a well-known finding in corrected Tetralogy of Fallot. Complications are rare but can be life-threatening. Standard 1-dimensional (1D) measurements have several limitations. We sought to establish contrast-enhanced magnetic resonance angiography cross-sectional areas of the aorta that could serve as reference values and to identify parameters that are associated with aortic dilatation., Materials and Methods: We enrolled 101 children and adolescents. The aortic areas were measured at the level of the aortic sinus (AS), the sinotubular junction (STJ), the ascending aorta (AA), the brachiocephalic trunk (TBC), and the descending aorta (DA). Sex-specific aortic dimensions were presented as percentile curves as well as regression equations. Furthermore volumetric and functional parameters as well as clinical data were analyzed to identify parameters that are associated with aortic dilatation., Results: Aortic areas (mm) for female subjects were 139+366×body surface area (BSA) for the AS, 134+255×BSA for the STJ, 113+239×BSA for the AA, 88+185×BSA proximal to the TBC, and 2.9+88×BSA for the DA. Aortic areas (mm) for male subjects were 162+403×BSA for the AS, 171+258×BSA for the STJ, 151+233×BSA for the AA, 73+206×BSA proximal to the TBC, and 21+80×BSA for the DA. The postoperative interval and age at examination were parameters associated with aortic size., Conclusions: We provide aortic areas in children and adolescents after correction of Tetralogy of Fallot measured by contrast-enhanced magnetic resonance angiography. Our 2D data may better depict the geometry of enlarged aortae than standard 1D diameters and serve as reference values for evaluating aortic disease in these patients.

Aims: The aim of this study was to assess silent and clinically apparent cerebral embolic events in patients undergoing transcatheter left atrial appendage closure., Methods and Results: In this prospective single-centre study, 28 patients underwent percutaneous closure of the left atrial appendage. In all patients, a diffusion-weighted magnetic resonance imaging (DW-MRI) study was performed before, the day after the procedure, and during routine follow-up after 45 days. All patients underwent neurological assessment at the time of DW-MRI. Additionally, transcranial Doppler ultrasound monitoring (TCD) for the detection of microembolic material during the procedure was performed. The procedure was successfully completed in all patients. New embolic lesions were detected in nine patients (32%) after the procedure, of which three (33%) were detectable as gliotic lesions at follow-up. One (3.6%) new lesion was observed at 45-day follow-up. Neurological assessment showed no neurological deficits. We observed no relationship between the numbers of microembolic signals on TCD monitoring and the occurrence of cerebral infarctions on DW-MRI., Conclusions: New cerebral embolic events occur after transcatheter closure of the left atrial appendage. However, most of the lesions demonstrate no gliotic transformation at follow-up. In all patients, the cerebral lesions were clinically unapparent.

Objectives: To evaluate the feasibility of performing comprehensive Cardiac Magnetic resonance (CMR) guided electrophysiological (EP) interventions in a porcine model encompassing left atrial access., Methods: After introduction of two femoral sheaths 14 swine (41 ± 3.6 kg) were transferred to a 1.5 T MR scanner. A three-dimensional whole-heart sequence was acquired followed by segmentation and the visualization of all heart chambers using an image-guidance platform. Two MR conditional catheters were inserted. The interventional protocol consisted of intubation of the coronary sinus, activation mapping, transseptal left atrial access (n = 4), generation of ablation lesions and eventually ablation of the atrioventricular (AV) node. For visualization of the catheter tip active tracking was used. Catheter positions were confirmed by passive real-time imaging., Results: Total procedure time was 169 ± 51 minutes. The protocol could be completed in 12 swine. Two swine died from AV-ablation induced ventricular fibrillation. Catheters could be visualized and navigated under active tracking almost exclusively. The position of the catheter tips as visualized by active tracking could reliably be confirmed with passive catheter imaging., Conclusions: Comprehensive CMR-guided EP interventions including left atrial access are feasible in swine using active catheter tracking., Key Points: • Comprehensive CMR-guided electrophysiological interventions including LA access were conducted in swine. • Active catheter-tracking allows efficient catheter navigation also in a transseptal approach. • More MR-conditional tools are needed to facilitate left atrial interventions in humans.

Background: Even if lower vaginal delivery success rates and impaired neonatal short-term outcomes have been reported for primiparous women with breech presentation, vaginal breech delivery remains an option for carefully selected patients. Because Magnetic resonance imaging (MRI) pelvimetry can provide additional information on maternal pelvic morphology, we sought to identify new MRI parameters that predict successful vaginal breech delivery., Methods: In this retrospective unicentre study, 240 primiparous women with breech presentation at term underwent MRI pelvimetry. For all patients vaginal delivery was planned, according to German guidelines and if the conjugata vera (CV) was ≥12 cm. The patients with uneventful vaginal deliveries and the patients who underwent a secondary caesarean section were compared according to pelvimetric parameters and outcomes. Regression analyses were performed., Results: In the vaginal delivery group (n = 162, (67.5%)), the distance between the spinae ischiadicae (interspinous diameter, ISD) was significantly enlarged. The ISD significantly influenced the mode of delivery in the regression analyses. The CV did not significantly differ between the groups. The patients with successful vaginal deliveries were significantly younger than the patients who underwent caesarean section. In the receiver operating characteristic (ROC) analysis, the area under the curve (AUC) for ISD was 67.7% (p<0.001, 95% CI [0.303-0.642]) and was higher considering the mother's age (AUC = 73.1%, p<0.001, 95% CI [0.662-0.800]). The neonatal short-term outcomes were comparable in both groups., Conclusion: The additional use of ISD may predict successful vaginal breech delivery and may be superior to the CV, which is more commonly used., Trial Registration: DRKS00009957.

Background: Data suggest that T1 and T2 mapping have excellent diagnostic accuracy in patients with suspected myocarditis. However, the true diagnostic performance of comprehensive cardiac magnetic resonance (CMR) mapping versus endomyocardial biopsy (EMB) has not been determined., Objectives: This study assessed the performance of CMR imaging, including T1 and T2 mapping, compared with EMB in an unselected, consecutive patient cohort with suspected myocarditis. It also examined the potential role of CMR field strength by comparing 1.5-T versus 3.0-T imaging., Methods: Patients underwent biventricular EMB, cardiac catheterization (for exclusion of coronary artery disease), and CMR imaging on 1.5- and 3-T scanners. The CMR protocol included current standard Lake Louise criteria (LLC) for myocarditis as well as native T1, calculation of extracellular volume fraction (ECV), and T2 mapping (only on 1.5-T). Patients were divided into 2 groups according to symptom duration (acute: ≤14 days vs. chronic: >14 days)., Results: A total of 129 patients underwent 1.5-T imaging. In patients with acute symptoms, native T1 yielded the best diagnostic performance as defined by the area under the curve (AUC) of receiver-operating curves (0.82) followed by T2 (0.81), ECV (0.75), and LLC (0.56). In patients with chronic symptoms, only T2 mapping yielded an acceptable AUC (0.77). On 3.0-T, AUCs of native T1, ECV, and LLC were comparable to 1.5-T with no significant differences., Conclusions: In patients with acute symptoms, mapping techniques provide a useful tool for confirming or rejecting the diagnosis of myocarditis and are superior to the LLC. However, only T2 mapping has acceptable diagnostic performance in patients with chronic symptoms. (Magnetic Resonance Imaging in Myocarditis [MyoRacer]; NCT02177630)., (Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Aims: Recently cardiac magnetic resonance (CMR) imaging has been found feasible for the visualization of the underlying substrate for cardiac arrhythmias as well as for the visualization of cardiac catheters for diagnostic and ablation procedures. Real-time CMR-guided cavotricuspid isthmus ablation was performed in a series of six patients using a combination of active catheter tracking and catheter visualization using real-time MR imaging., Methods and Results: Cardiac magnetic resonance utilizing a 1.5 T system was performed in patients under deep propofol sedation. A three-dimensional-whole-heart sequence with navigator technique and a fast automated segmentation algorithm was used for online segmentation of all cardiac chambers, which were thereafter displayed on a dedicated image guidance platform. In three out of six patients complete isthmus block could be achieved in the MR scanner, two of these patients did not need any additional fluoroscopy. In the first patient technical issues called for a completion of the procedure in a conventional laboratory, in another two patients the isthmus was partially blocked by magnetic resonance imaging (MRI)-guided ablation. The mean procedural time for the MR procedure was 109 ± 58 min. The intubation of the CS was performed within a mean time of 2.75 ± 2.21 min. Total fluoroscopy time for completion of the isthmus block ranged from 0 to 7.5 min., Conclusion: The combination of active catheter tracking and passive real-time visualization in CMR-guided electrophysiologic (EP) studies using advanced interventional hardware and software was safe and enabled efficient navigation, mapping, and ablation. These cases demonstrate significant progress in the development of MR-guided EP procedures., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.)

Introduction: Dilatation of the ascending aorta is a common finding in Tetralogy of fallot (TOF). We sought to provide aortic dimensions in children and adolescents after corrected TOF obtained by contrast-enhanced cardiac-magnetic-resonance angiography (CE-CMRA) that could serve as reference values., Materials and Methods: We enrolled 101 children and adolescents (56 male) with a median age of 10.9 years. All patients underwent CE-CMRA imaging using a 3-dimensional spoiled gradient-echo-sequence. Aortic diameters were measured at the level of the aortic valve (AV), aortic sinus (AS), sino-tubular junction (STJ) and the ascending aorta (AA) and compared with normal values obtained from literature. Sex-specific aortic dimensions are given as percentile curves as well as z scores. Furthermore CMR volumetric and functional parameters as well as clinical and anamnestic data were analyzed to identify parameters that are associated with aortic dilatation., Results: Diameters for aortic size for males were 3.6 + 16.6*BSA(0.5) at the AV level, 7.0 + 19.5*BSA(0.5) at the AS level, 7.0 + 14.4*BSA(0.5) at the STJ level and 7.3 + 15.5*BSA(0.5) at the AA level. Diameters for females were 5.8 + 14.1*BSA(0.5) at the AV level, 7.2 + 17.6*BSA(0.5) at the AS level, 5.2 + 15.4*BSA(0.5) at the STJ level and 2.0 + 17.8*BSA(0.5) at the AA level. All diameters in TOF patients were larger compared with normal values. The postoperative interval and age at examination were the only parameters associated with aortic size at all measured levels., Conclusion: We provide CE-CMRA data of aortic dimensions in children and adolescents after correction of TOF. Our data might be useful for an estimation of the "normal" aortic size in this patient cohort and can serve as a basis for future longitudinal studies adding prognostic data.

Purpose: 4D PC-MRI enables the noninvasive measurement of time-resolved, three-dimensional blood flow data that allow quantification of the hemodynamics. Stroke volumes are essential to assess the cardiac function and evolution of different cardiovascular diseases. The calculation depends on the wall position and vessel orientation, which both change during the cardiac cycle due to the heart muscle contraction and the pumped blood. However, current systems for the quantitative 4D PC-MRI data analysis neglect the dynamic character and instead employ a static 3D vessel approximation. We quantify differences between stroke volumes in the aorta obtained with and without consideration of its dynamics., Methods: We describe a method that uses the approximating 3D segmentation to automatically initialize segmentation algorithms that require regions inside and outside the vessel for each temporal position. This enables the use of graph cuts to obtain 4D segmentations, extract vessel surfaces including centerlines for each temporal position and derive motion information. The stroke volume quantification is compared using measuring planes in static (3D) vessels, planes with fixed angulation inside dynamic vessels (this corresponds to the common 2D PC-MRI) and moving planes inside dynamic vessels., Results: Seven datasets with different pathologies such as aneurysms and coarctations were evaluated in close collaboration with radiologists. Compared to the experts' manual stroke volume estimations, motion-aware quantification performs, on average, 1.57% better than calculations without motion consideration. The mean difference between stroke volumes obtained with the different methods is 7.82%. Automatically obtained 4D segmentations overlap by 85.75% with manually generated ones., Conclusion: Incorporating motion information in the stroke volume quantification yields slight but not statistically significant improvements. The presented method is feasible for the clinical routine, since computation times are low and essential parts run fully automatically. The 4D segmentations can be used for other algorithms as well. The simultaneous visualization and quantification may support the understanding and interpretation of cardiac blood flow.

Objective: To test the hypothesis that myocardial scars after repair of tetralogy of Fallot are related to impaired cardiac function and adverse clinical outcome., Methods: A total of 53 patients were retrospectively analysed after repair of tetralogy of Fallot. The median patient age was 20 years (range 2-48). Cardiac MRI with a 1.5 T magnet included cine sequences to obtain volumes and function, phase-sensitive inversion recovery delayed enhancement imaging to detect myocardial scars, and flow measurements to determine pulmonary regurgitation fraction. In addition, clinical parameters were obtained., Results: An overall 83% of patients were in NYHA class I. All patients with the exception of 2 (96%) had pulmonary insufficiency. Mean ejection fraction and end-diastolic volume index were 46% and 128 ml/m2 for the right ventricle and 54% and 82 ml/m² for the left ventricle, respectively. Excluding enhancement of the septal insertion and prosthetic patches, delayed enhancement was seen in 11/53 cases (21%). Delayed enhancement of the right ventricle was detected in 6/53 patients (11%) and of the left ventricle in 5/53 patients (9%). The patient group with delayed enhancement was significantly older (p=0.003), had later repair (p=0.007), and higher left ventricular myocardial mass index (p=0.009) compared with the group without delayed enhancement., Conclusions: This study reveals that scarring is common in patients after surgical repair of tetralogy of Fallot and is associated with older age and late repair. However, there was no difference in right ventricular function, NYHA class, or occurrence of clinically relevant arrhythmias between patients with and those without myocardial scars.

To compare the performance of semi-automatic versus manual segmentation for ECG-triggered cardiovascular computed tomography (CT) examinations prior to transcatheter aortic valve replacement (TAVR), with focus on the speed and precision of experienced versus inexperienced observers. The preoperative ECG-triggered CT data of 30 consecutive patients who were scheduled for TAVR were included. All datasets were separately evaluated by two radiologists with 1 and 5 years of experience (novice and expert, respectively) in cardiovascular CT using an evaluation software program with or without a semi-automatic TAVR workflow. The time expended for data loading and all segmentation steps required for the implantation planning were assessed. Inter-software as well as inter-observer reliability analysis was performed. The CT datasets were successfully evaluated, with mean duration between 520.4 ± 117.6 s and 693.2 ± 159.5 s. The three most time-consuming steps were the 3D volume rendering, the measurement of aorta diameter and the sizing of the aortic annulus. Using semi-automatic segmentation, a novice could evaluate CT data approximately 12.3% faster than with manual segmentation, and an expert could evaluate CT data approximately 10.3% faster [mean differences of 85.4 ± 83.8 s (p < 0.001) and 59.8 ± 101 s (p < 0.001), respectively]. The inter-software reliability for a novice was slightly lower than for an expert; however, the reliability for a novice and expert was excellent (ICC 0.92, 95% CI 0.75-0.97/ICC 0.96, 95% CI 0.91-0.98). Automatic aortic annulus detection failed in two patients (6.7%). The study revealed excellent inter-software and inter-observer reliability, with a mean ICC of 0.95. TAVR evaluation can be accomplished significantly faster with semi-automatic rather than with manual segmentation, with comparable exactness, showing a benefit for experienced and inexperienced observers.

Background: In the autonomic nerve system most sympathetic neurons synapse peripherally in the ganglia of the sympathetic trunk. A reduction in sympathicotonia by partial elimination of these ganglia is a therapeutic approach that has been used for more than 100 years. In the early 1920s the first attempts at percutaneous sympathicolysis (SL) were carried out. Nowadays, minimally invasive image-guided SL has become an integral part of interventional radiology. Established indications for SL are hyperhidrosis, critical limb ischemia and the complex regional pain syndrome., Methods: The standard imaging guidance modality in SL is computed tomography (CT) which allows the exact placement of the puncture needle in the target area under visualization of the surrounding structures. Ethanol is normally used for chemical lysis, which predominantly eliminates the unmyelinated autonomic axons. In order to visualize the distribution of the ethanol during application, iodine-containing contrast medium is added., Results: The sympathetic nervous system (SNS) controls sweat secretion via the efferent neurons; therefore, effective therapy of idiopathic palmar, axillary and plantar hyperhidrosis can be achieved when SL is performed at the corresponding level of the sympathetic trunk. Furthermore, due to the vasomotor innervation of most blood vessels, by reduction of the sympathicotonus an atony of the smooth muscles and therefore vasodilatation occurs, which is used as a palliative therapeutic option in patients with critical limb ischemia. By elimination of the afferent sensory fibers this also results in pain relief. This principle is also used in the SL therapy of the complex regional pain syndrome., Conclusion: After the introduction of CT guidance, major complications have become rare events. In addition to the usual risks of percutaneous interventions there are, however, a number of specific complications, such as syncope caused by irritation of cardiac sympathetic nerves in thoracic SL and ureteral injury in lumbar SL.

Radiofrequency (RF) ablation with irrigated tip catheters decreases the likelihood of thrombus and char formation and enables the creation of larger lesions. Due to the potential dramatic consequences, the prevention of thromboembolic events is of particular importance for left-sided procedures. Although acute success rates of ventricular tachycardia (VT) ablation are satisfactory, recurrence rate is high. Apart from the progress of the underlying disease, reconduction and the lack of effective transmural lesions play a major role for VT recurrences. This paper reviews principles of lesion formation with radiofrequency and the effect of tip irrigation as well as recent advances in new technology. Potential areas of further development of catheter technology might be the improvement of mapping by better substrate definition and resolution, the introduction of bipolar and multipolar ablation techniques into clinical routine, and the use of alternative sources of energy.

Purpose: To compare the performance of server-based (CSS) versus stand-alone post-processing software (ES) for the evaluation of cardiovascular CT examinations (cvCT) and to determine the crucial steps., Materials and Methods: Data of 40 patients (20 patients for coronary artery evaluation and 20 patients prior to transcatheter aortic valve implantation [TAVI]) were evaluated by 5 radiologists with CSS and ES. Data acquisition was performed using a dual-source 128-row CT unit (SOMATOM Definition Flash, Siemens, Erlangen, Germany) and a 64-row CT unit (Brilliance 64, Philips, Hamburg, Germany). The following workflow was evaluated: Data loading, aorta and coronary segmentation, curved multiplanar reconstruction (cMPR) and 3 D volume rendering technique (3D-VRT), measuring of coronary artery stenosis and planimetry of the aortic annulus. The time requirement and subjective quality for the workflow were evaluated., Results: The coronary arteries as well as the TAVI data could be evaluated significantly faster with CSS (5.5  ±  2.9  min and 8.2  ±  4.0  min, respectively) than with ES (13.9  ±  5.2  min and 15.2  ±  10.9  min, respectively, p ≤  0.01). Segmentation of the aorta (CSS: 1.9 ±  2.0  min, ES: 3.7  ±  3.3  min), generating cMPR of coronaries (CSS: 0.5  ±  0.2  min, ES: 5.1  ±  2.6  min), aorta and iliac vessels (CSS: 0.5  ±  0.4  min and 0.4  ±  0.4  min, respectively, ES: 1.6  ±  0.7  min and 2.8  ±  3  min, respectively) could be performed significantly faster with CSS than with ES with higher quality of cMPR, measuring of coronary stenosis and 3D-VRT (p < 0.05)., Conclusion: Evaluation of cvCT can be accomplished significantly faster and better with CSS than with ES.  The segmentation remains the most time-consuming workflow step, so optimization of segmentation algorithms could improve performance even further., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: Intramyocardial haemorrhage (IMH) and microvascular obstruction (MVO) represent reperfusion injury after reperfused ST-elevation myocardial infarction (STEMI) with prognostic impact and "hypointense core" (HIC) appearance in T2-weighted images. We aimed to distinguish between IMH and MVO by using T2 (*)-weighted cardiovascular magnetic resonance imaging (CMR) and analysed influencing factors for IMH development., Methods and Results: A total of 151 patients with acute STEMI underwent CMR after primary angioplasty. T2-STIR sequences were used to identify HIC, late gadolinium enhancement to visualise MVO and T2 (*)-weighted sequences to detect IMH. IMH(+)/IMH(-) patients were compared considering infarct size, myocardial salvage, thrombolysis in myocardial infarction (TIMI) flow, reperfusion time, ventricular volumes, function and pre-interventional medication. Seventy-six patients (50%) were IMH(+), 82 (54%) demonstrated HIC and 100 (66%) MVO. IMH was detectable without HIC in 16 %, without MVO in 5% and HIC without MVO in 6%. Multivariable analyses revealed that IMH was associated with significant lower left ventricular ejection fraction and myocardial salvage index, larger left ventricular volume and infarct size. Patients with TIMI flow grade ≤1 before angioplasty demonstrated IMH significantly more often., Conclusions: IMH is associated with impaired left ventricular function and higher infarct size. T2 and HIC imaging showed moderate agreement for IMH detection. T2 (*) imaging might be the preferred CMR imaging method for comprehensive IMH assessment., Key Points: Intramyocardial haemorrhage is a common finding in patients with acute reperfused myocardial-infarction. T 2 (*) imaging should be the preferred CMR method for assessment of intramyocardial haemorrhage. Intramyocardial haemorrhage can be considered as an important influencing factor on patient's outcome.

Background: The aim of this study was to analyze the angle between the left ventricular (LV) long axis and the LV outflow tract (αLV-LVOT) on cardiac computed tomography and to describe its effect on the occurrence of paravalvular leakage (PL), fluoroscopy time, and postoperative creatine kinase-MB levels in transapical transcatheter aortic valve replacement (TA-TAVR)., Methods: High-risk patients with severe aortic stenosis scheduled for TA-TAVR using an Edwards SAPIEN (Edwards Lifesciences, Irvine, CA) prosthesis were retrospectively included. The αLV-LVOT was measured during systole and diastole as far as retrospectively gated data sets were available. The αLV-LVOT was correlated with the occurrence of PL, total fluoroscopy time, and postoperative creatine kinase-MB levels. Interobserver variability was assessed in all cases., Results: The study included 81 patients (57 women [70.4%], 24 men [29.6%]) with an average age of 81.9±5.8 years. The mean αLV-LVOTs were 61.8±9.9 degrees during systole and 61.1±10.0 degrees during diastole. There was a minimal, nonsignificant change in the αLV-LVOT between systole and diastole of 0.2±4.1 degrees (p=0.7). PL was found in 39 patients: grade 0 in 42 (51.9%), grade I in 30 (37.0%), and grade II in 9 (11.1%). Patients with a clinically significant PL (grade≥II) showed a significantly greater mean αLV-LVOT than patients with grade I or without PL (mean difference, 13.8±3.2 degrees; p<0.001). No significant correlation was found between the αLV-LVOT and total fluoroscopy time (r=-0.17, p=0.16) and postoperative creatine kinase-MB levels (r=-0.1, p=0.44)., Conclusions: During TA-TAVR, greater αLV-LVOTs were associated with significantly higher grades of PL. Thus, the αLV-LVOT might influence the selection of the transapical implantation path and could have a significant effect on designs for future stents or novel delivery devices., (Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objective: Comparing the diagnostic value of multi-sequential cardiac magnetic resonance imaging (CMR) with endomyocardial biopsy (EMB) for sub-clinical cardiac allograft rejection., Methods: One hundred and forty-six examinations in 73 patients (mean age 53 ± 12 years, 58 men) were performed using a 1.5 Tesla system and compared to EMB. Examinations included a STIR (short tau inversion recovery) sequence for calculation of edema ratio (ER), a T1-weighted spin-echo sequence for assessment of global relative enhancement (gRE), and inversion-recovery sequences to visualize late gadolinium enhancement (LGE). Histological grade ≥1B was considered relevant rejection., Results: One hundred and twenty-seven (127/146 = 87 %) EMBs demonstrated no or mild signs of rejection (grades ≤1A) and 19/146 (13 %) a relevant rejection (grade ≥1B). Sensitivity, specificity, positive predictive, and negative predictive values were as follows: ER: 63 %, 78 %, 30 %, and 93 %; gRE: 63 %, 70 %, 24 %, and 93 %; LGE: 68 %, 36 %, 13 %, and 87 %; with the combination of ER and gRE with at least one out of two positive: 84 %, 57 %, 23 %, and 96 %. ROC analysis revealed an area under the curve of 0.724 for ER and 0.659 for gRE., Conclusion: CMR parameters for myocarditis are useful to detect sub-clinical acute cellular rejection after heart transplantation. Comparable results to myocarditis can be achieved with a combination of parameters., Key Points: • Magnetic resonance imaging is useful for the assessment of cardiac allograft rejection. • CMR has a high negative predictive value for exclusion of allograft rejection. • Diagnostic performance is not yet good enough to replace endomyocardial biopsy.