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Jones CF, Quarrington RD, Tsangari H, Starczak Y, Mulaibrahimovic A, Burzava ALS, Christou C, Barker AJ, Morel J, Bright R, Barker D, Brown T, Vasilev K, Anderson PH. A Novel Nanostructured Surface on Titanium Implants Increases Osseointegration in a Sheep Model. Clin Orthop Relat Res 2022; 480:2232-2250. [PMID: 36001022 PMCID: PMC10476811 DOI: 10.1097/corr.0000000000002327] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 06/28/2022] [Indexed: 01/31/2023]
Abstract
BACKGROUND A nanostructured titanium surface that promotes antimicrobial activity and osseointegration would provide the opportunity to create medical implants that can prevent orthopaedic infection and improve bone integration. Although nanostructured surfaces can exhibit antimicrobial activity, it is not known whether these surfaces are safe and conducive to osseointegration. QUESTIONS/PURPOSES Using a sheep animal model, we sought to determine whether the bony integration of medical-grade, titanium, porous-coated implants with a unique nanostructured surface modification (alkaline heat treatment [AHT]) previously shown to kill bacteria was better than that for a clinically accepted control surface of porous-coated titanium covered with hydroxyapatite (PCHA) after 12 weeks in vivo. The null hypothesis was that there would be no difference between implants with respect to the primary outcomes: interfacial shear strength and percent intersection surface (the percentage of implant surface with bone contact, as defined by a micro-CT protocol), and the secondary outcomes: stiffness, peak load, energy to failure, and micro-CT (bone volume/total volume [BV/TV], trabecular thickness [Tb.Th], and trabecular number [Tb.N]) and histomorphometric (bone-implant contact [BIC]) parameters. METHODS Implants of each material (alkaline heat-treated and hydroxyapatite-coated titanium) were surgically inserted into femoral and tibial metaphyseal cancellous bone (16 per implant type; interference fit) and in tibial cortices at three diaphyseal locations (24 per implant type; line-to-line fit) in eight skeletally mature sheep. At 12 weeks postoperatively, bones were excised to assess osseointegration of AHT and PCHA implants via biomechanical push-through tests, micro-CT, and histomorphometry. Bone composition and remodeling patterns in adult sheep are similar to that of humans, and this model enables comparison of implants with ex vivo outcomes that are not permissible with humans. Comparisons of primary and secondary outcomes were undertaken with linear mixed-effects models that were developed for the cortical and cancellous groups separately and that included a random effect of animals, covariates to adjust for preoperative bodyweight, and implant location (left/right limb, femoral/tibial cancellous, cortical diaphyseal region, and medial/lateral cortex) as appropriate. Significance was set at an alpha of 0.05. RESULTS The estimated marginal mean interfacial shear strength for cancellous bone, adjusted for covariates, was 1.6 MPa greater for AHT implants (9.3 MPa) than for PCHA implants (7.7 MPa) (95% CI 0.5 to 2.8; p = 0.006). Similarly, the estimated marginal mean interfacial shear strength for cortical bone, adjusted for covariates, was 6.6 MPa greater for AHT implants (25.5 MPa) than for PCHA implants (18.9 MPa) (95% CI 5.0 to 8.1; p < 0.001). No difference in the implant-bone percent intersection surface was detected for cancellous sites (cancellous AHT 55.1% and PCHA 58.7%; adjusted difference of estimated marginal mean -3.6% [95% CI -8.1% to 0.9%]; p = 0.11). In cortical bone, the estimated marginal mean percent intersection surface at the medial site, adjusted for covariates, was 11.8% higher for AHT implants (58.1%) than for PCHA (46.2% [95% CI 7.1% to 16.6%]; p < 0.001) and was not different at the lateral site (AHT 75.8% and PCHA 74.9%; adjusted difference of estimated marginal mean 0.9% [95% CI -3.8% to 5.7%]; p = 0.70). CONCLUSION These data suggest there is stronger integration of bone on the AHT surface than on the PCHA surface at 12 weeks postimplantation in this sheep model. CLINICAL RELEVANCE Given that the AHT implants formed a more robust interface with cortical and cancellous bone than the PCHA implants, a clinical noninferiority study using hip stems with identical geometries can now be performed to compare the same surfaces used in this study. The results of this preclinical study provide an ethical baseline to proceed with such a clinical study given the potential of the alkaline heat-treated surface to reduce periprosthetic joint infection and enhance implant osseointegration.
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Lee J, El Hangouche N, Pathrose A, Soulat G, Barker AJ, Thomas JD, Markl M. Bicuspid aortic valve morphology and hemodynamics by same-day echocardiography and cardiac MRI. THE INTERNATIONAL JOURNAL OF CARDIOVASCULAR IMAGING 2022; 38:2047-2056. [PMID: 35294708 DOI: 10.1007/s10554-022-02593-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 03/07/2022] [Indexed: 11/28/2022]
Abstract
This study investigated the impact of bicuspid aortic valve (BAV) on valve morphology and motion as well as proximal and aortic hemodynamics using a same-day echocardiography and cardiac MRI. Transthoracic echocardiography, two-dimensional cine MRI of the aortic valve, and aortic 4D flow MRI were performed on the same day in 9 normofunctional BAV patients (age = 41 ± 12, 3 female), 4 BAV with moderate to severe aortic stenosis (AS) (age = 63 ± 5, 1 female), and 36 healthy tricuspid aortic valve controls (age = 52 ± 10, 21 female). Valve opening and closing timings and transvalvular peak velocity were measured using B-mode and Doppler echocardiogram, respectively. Valve orifice morphology at a fully-opened state was characterized using cine MRI. Ascending aortic (AAo) wall shear stress (WSS) was measured using 4D flow MRI data. Valve motion timings were similar between BAV and controls. BAV was associated with an increased orifice aspect ratio (1.44 ± 0.11 vs. 1.10 ± 0.13, P < 0.001), transvalvular peak velocity (1.5 ± 0.3 vs. 1.2 ± 0.2 m/s, P < 0.001) and maximum AAo WSS (1.62 ± 0.31 vs. 0.91 ± 0.24 Pa, P < 0.001). The increased orifice aspect ratio was associated with the increase in transvalvular peak velocity (r = 0.80, P < 0.0001) and maximum AAo WSS (r = 0.83, P < 0.0001). Transvalvular peak velocity was also positively correlated with maximum AAo WSS (r = 0.83, P < 0.0001). A same-day echo and MRI imaging allows for a comprehensive assessment of the impact of aortic valve disease on valve function and hemodynamics. In this pilot application to BAV, we found increased orifice aspect ratio may be responsible for increased transvalvular peak velocity and maximum AAo WSS.
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Shan Y, Li J, Wu B, Barker AJ, Markl M, Lin J, Shu X, Wang Y. Aortic Viscous Energy Loss for Assessment of Valve-related
Hemodynamics in Asymptomatic Severe Aortic Stenosis. Radiol Cardiothorac Imaging 2022; 4:e220010. [PMCID: PMC9434981 DOI: 10.1148/ryct.220010] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 06/26/2022] [Accepted: 07/15/2022] [Indexed: 08/29/2023]
Abstract
Purpose To investigate whether functional assessment of aberrant flow patterns by viscous energy loss (E′L ) using four-dimensional (4D) flow MRI could determine aortic stenosis (AS) severity in accordance with transvalvular energy loss and aid in surgical decision-making in asymptomatic patients with severe AS. Materials and Methods In this prospective, single-center study, E′L was measured in the thoracic aorta of 74 consecutive asymptomatic patients with severe AS and preserved left ventricular ejection fraction who presented between January 2015 and December 2017, and 23 healthy volunteers using 4D flow MRI. Transvalvular energy loss was assessed based on the energy loss index (ELI) measured using Doppler echocardiography. The association between E′L and AS-related events including aortic valve replacement was evaluated by receiver operating characteristic curve analysis, Kaplan-Meier analysis, and multivariable Cox regression analysis. Results Among 74 asymptomatic patients with severe AS (mean age, 60 years ± 9 [SD]; 43 men; 56 with bicuspid aortic valve), 33 experienced AS-related events during a median follow-up of 42 months (IQR, 30–53 months). Altered flow patterns in severe AS resulted in a sevenfold increase in peak systolic E′L in the ascending aorta compared with controls (13.9 mW ± 3.4 vs 1.80 mW ± 0.44; P < .001). Peak systolic E′L in the ascending aorta was independently associated with the ELI (standardized β, −0.52; P < .001) and showed better discrimination for AS-related events (area under the curve, 0.83; 95% CI: 0.74, 0.93; P < .001) than conventional echocardiographic parameters. After adjustment for confounding variables, peak systolic E′L in the ascending aorta was associated with a significant increase in AS-related events (P < .001 for adjusted hazard ratio). Conclusion Changes in AS-mediated poststenotic three-dimensional outflow patterns can be quantified by 4D flow MRI-derived energetic markers to aid in the risk stratification and clinical management of asymptomatic patients with severe AS. Keywords: Aortic Stenosis, 4D Flow MRI, Flow Energetics, Vascular, Aorta, Aortic Valve, MR Angiography Supplemental material is available for this article. © RSNA, 2022
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Huh H, Lee J, Kinno M, Markl M, Thomas JD, Barker AJ. Two wrongs sometimes do make a right: errors in aortic valve stenosis assessment by same-day Doppler echocardiography and 4D flow MRI. Int J Cardiovasc Imaging 2022; 38:1815-1823. [PMID: 35190940 PMCID: PMC9392814 DOI: 10.1007/s10554-022-02553-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 02/04/2022] [Indexed: 11/28/2022]
Abstract
This study aims to systematically verify if the simplified geometry and flow profile of the left ventricular outflow tract (LVOT) assumed in 2D echocardiography is appropriate while examining the utility of 4D flow MRI to assess valvular disease. This prospective study obtained same-day Doppler echocardiography and 4D flow MRI in 37 healthy volunteers (age: 51.9 ± 18.2, 20 females) and 7 aortic stenosis (AS) patients (age: 64.2 ± 9.6, 1 female). Two critical assumptions made in echocardiography for aortic valve area assessment were examined, i.e. the assumption of (1) a circular LVOT shape and (2) a flat velocity profile through the LVOT. 3D velocity and shape information obtained with 4D flow MRI was used as comparison. It was found that the LVOT area was lower (by 26.5% and 24.5%) and the velocity time integral (VTI) was higher (by 28.5% and 30.2%) with echo in the healthy and AS group, respectively. These competing errors largely cancelled out when examining individual and cohort averaged LVOT stroke volume. The LVOT area, VTI and stroke volume measured by echo and 4D flow MRI were 3.6 ± 0.7 vs. 4.9 ± 1.0 cm2 (p < 0.001), 21.2 ± 3.0 vs 15.2 ± 2.8 cm (p < 0.001), and 75.6 ± 15.6 vs 72.8 ± 14.1 ml (p = 0.3376), respectively. In the ensemble average of LVOT area and VTI, under- and over-estimation seem to compensate each other to result in a 'realistic' stroke volume. However, it is important to understand that this compensation may fail. 4D flow MRI provides a unique insight into this phenomenon.
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Jarvis K, Scott MB, Soulat G, Elbaz MSM, Barker AJ, Carr JC, Markl M, Ragin A. Aortic Pulse Wave Velocity Evaluated by 4D Flow MRI Across the Adult Lifespan. J Magn Reson Imaging 2022; 56:464-473. [PMID: 35001455 PMCID: PMC9387532 DOI: 10.1002/jmri.28045] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 12/19/2021] [Accepted: 12/20/2021] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND Evaluation of aortic stiffness by pulse wave velocity (PWV) across the adult lifespan is needed to better understand normal aging in women and men. PURPOSE To characterize PWV in the thoracic aorta using 4D flow MRI in an age- and sex-stratified cohort of healthy adults. STUDY TYPE Retrospective. POPULATION Ninety nine healthy participants (age: 46 ± 15 [19-79] years, 50% female), divided into young adults (<45 years) (N = 48), midlife (45-65 years) (N = 37), and later life (>65 years) (N = 14) groups. FIELD STRENGTH/SEQUENCE 1.5 T or 3 T, 2D cine bSSFP, 4D flow MRI. ASSESSMENT Cardiac functional parameters of end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and myocardial mass were assessed by 2D cine bSSFP. PWV and aortic blood flow velocity were assessed by 4D flow MRI. Reproducibility of PWV was evaluated in a subset of nine participants. STATISTICAL TESTS Analysis of variance, Pearson's correlation coefficient (r), linear regression, intraclass correlation coefficient (ICC). A P value < 0.05 was considered statistically significant. RESULTS PWV increased significantly with age (young adults: 5.4 ± 0.9 m/sec, midlife: 7.2 ± 1.1 m/sec, and later life: 9.4 ± 1.8 m/sec) (r = 0.79, slope = 0.09 m/sec/year). PWV did not differ in women and men in entire sample (P = 0.40) or within age groups (young adults: P = 0.83, midlife: P = 0.17, and later life: P = 0.96). PWV was significantly correlated with EDV (r = -0.29), ESV (r = -0.23), SV (r = -0.28), myocardial mass (r = 0.21), and mean aortic blood flow velocity (r = -0.62). In the test-retest subgroup (N = 9), PWV was 6.7 ± 1.5 [4.4-9.3] m/sec and ICC = 0.75. DATA CONCLUSION 4D flow MRI quantified higher aortic PWV with age, by approximately 1 m/sec per decade, and significant differences between young adults, midlife and later life. Reproducibility analysis showed good test-retest agreement. Increased PWV was associated with decline in cardiac function and reduced aortic blood flow velocity. This study demonstrates the utility of 4D flow MRI-derived aortic PWV for studying aging. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 2.
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McLennan D, Schäfer M, Barker AJ, Mitchell MB, Ing RJ, Browne LP, Ivy DD, Morgan GJ. Abnormal flow conduction through pulmonary arteries is associated with right ventricular volume and function in patients with repaired tetralogy of Fallot: does flow quality affect afterload? Eur Radiol 2022; 33:302-311. [DOI: 10.1007/s00330-022-09017-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 05/27/2022] [Accepted: 07/04/2022] [Indexed: 11/04/2022]
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Nightingale M, Guzzardi DG, Barker AJ, Malaisrie SC, McCarthy PM, Markl M, Di Martino ES, Fedak PWM. Elastin integrity in bicuspid valve-associated aortopathy is associated with altered biomechanical properties and influenced by age. Ann Cardiothorac Surg 2022; 11:426-435. [PMID: 35958543 PMCID: PMC9357955 DOI: 10.21037/acs-2022-bav-17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 06/07/2022] [Indexed: 11/09/2022]
Abstract
Background Aortic wall remodelling in bicuspid aortic valve (BAV) patients is heterogeneous and characterized by elastin fiber breakdown alongside impaired biomechanics. However, the relationship between aortic histopathological changes and biomechanics are incompletely understood. We clarify the influence of elastin fiber integrity on ex vivo aortic wall mechanical properties in BAV patients, and explore the influence of patient age. Methods Aortic tissue samples (N=66) from 19 BAV patients undergoing prophylactic ascending aortic resection surgery were analyzed. Semi-quantitative histopathological analysis was conducted to assess elastin fiber integrity including elastin content and elastic fiber fragmentation. Ex vivo biaxial mechanical testing generated stress-strain curves from which physiological [low-strain tangential modulus (LTM), transition zone onset stress (TZo)] and supraphysiological [transition zone end stress (TZe) and high-strain tangential modulus (HTM)] mechanical properties were obtained. Relationships between histopathology and mechanical properties were determined using a linear mixed effect model. BAV patients were subdivided according to ‘younger’ and ‘older’ age groups (i.e., 51–60 and 61–70 years old, respectively). Results No statistically significant differences in elastin content were observed between younger and older BAV patients. Older patients showed greater elastin fiber fragmentation compared to their younger cohort (74% versus 61%). Elastin fiber histopathology was associated with differences in physiological mechanical properties: elastin fragmentation corresponded with lower LTM (P=0.005) and TZo (P=0.044) in younger BAV patients and higher LTM (P=0.049) and TZo (P=0.001) in older BAV patients. Histopathology changes were significantly associated with supraphysiological mechanical properties only in older BAV patients: decreased elastin integrity was associated with increased TZe (P=0.049) and HTM (P<0.001). Conclusions Elastin histopathologic changes in BAV aortopathy correspond with differences in mechanical properties and this relationship is influenced by patient age. These novel findings provide additional mechanistic insights into aortic wall remodeling and support a more nuanced stratification of BAV patients by age.
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Browne LP, Fujiwara T, Leahy RA, Friesen RM, Barker AJ. 4D flow MRI quantification and surveillance of veno-venous collateralization. Eur Heart J Cardiovasc Imaging 2022; 23:e466. [PMID: 35762621 DOI: 10.1093/ehjci/jeac122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Sunami S, Singh VP, Garrick D, Beregi A, Barker AJ, Luksch K, Bentine E, Mathey L, Foot CJ. Observation of the Berezinskii-Kosterlitz-Thouless Transition in a Two-Dimensional Bose Gas via Matter-Wave Interferometry. PHYSICAL REVIEW LETTERS 2022; 128:250402. [PMID: 35802452 DOI: 10.1103/physrevlett.128.250402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 12/15/2021] [Accepted: 04/18/2022] [Indexed: 06/15/2023]
Abstract
We probe local phase fluctuations of trapped two-dimensional Bose gases using matter-wave interferometry. This enables us to measure the phase correlation function, which changes from an algebraic to an exponential decay when the system crosses the Berezinskii-Kosterlitz-Thouless (BKT) transition. We determine the temperature dependence of the BKT exponent η and find the critical value η_{c}=0.17(3) for our trapped system. Furthermore, we measure the local vortex density as a function of the local phase-space density, which shows a scale-invariant behavior across the transition. Our experimental investigation is supported by Monte Carlo simulations and provides a comprehensive understanding of the BKT transition in a trapped system.
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Treglia A, Ambrosio F, Martani S, Folpini G, Barker AJ, Albaqami MD, De Angelis F, Poli I, Petrozza A. Effect of electronic doping and traps on carrier dynamics in tin halide perovskites. MATERIALS HORIZONS 2022; 9:1763-1773. [PMID: 35510702 PMCID: PMC9390658 DOI: 10.1039/d2mh00008c] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 03/30/2022] [Indexed: 05/27/2023]
Abstract
Tin halide perovskites have recently emerged as promising materials for low band gap solar cells. Much effort has been invested on controlling the limiting factors responsible for poor device efficiencies, namely self-p-doping and tin oxidation. Both phenomena are related to the presence of defects; however, full understanding of their implications in the optoelectronic properties of the material is still missing. We provide a comprehensive picture of the competing radiative and non-radiative recombination processes in tin-based perovskite thin films to establish the interplay between doping and trapping by combining photoluminescence measurements with trapped-carrier dynamic simulations and first-principles calculations. We show that pristine Sn perovskites, i.e. sample processed with commercially available SnI2 used as received, exhibit extremely high radiative efficiency due to electronic doping which boosts the radiative band-to-band recombination. Contrarily, thin films where Sn4+ species are intentionally introduced show drastically reduced radiative lifetime and efficiency due to a dominance of Auger recombination at all excitation densities when the material is highly doped. The introduction of SnF2 reduces the doping and passivates Sn4+ trap states but conversely introduces additional non-radiative decay channels in the bulk that fundamentally limit the radiative efficiency. Overall, we provide a qualitative model that takes into account different types of traps present in tin-perovskite thin films and show how doping and defects can affect the optoelectronic properties.
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Berhane H, Scott MB, Barker AJ, McCarthy P, Avery R, Allen B, Malaisrie C, Robinson JD, Rigsby CK, Markl M. Deep learning-based velocity antialiasing of 4D-flow MRI. Magn Reson Med 2022; 88:449-463. [PMID: 35381116 PMCID: PMC9050855 DOI: 10.1002/mrm.29205] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 01/13/2022] [Accepted: 02/07/2022] [Indexed: 01/03/2023]
Abstract
Purpose To develop a convolutional neural network (CNN) for the robust and fast correction of velocity aliasing in 4D‐flow MRI. Methods This study included 667 adult subjects with aortic 4D‐flow MRI data with existing velocity aliasing (n = 362) and no velocity aliasing (n = 305). Additionally, 10 controls received back‐to‐back 4D‐flow scans with systemically varied velocity‐encoding sensitivity (vencs) at 60, 100, and 175 cm/s. The no‐aliasing data sets were used to simulate velocity aliasing by reducing the venc to 40%–70% of the original, alongside a ground truth locating all aliased voxels (153 training, 152 testing). The 152 simulated and 362 existing aliasing data sets were used for testing and compared with a conventional velocity antialiasing algorithm. Dice scores were calculated to quantify CNN performance. For controls, the venc 175‐cm/s scans were used as the ground truth and compared with the CNN‐corrected venc 60 and 100 cm/s data sets Results The CNN required 176 ± 30 s to perform compared with 162 ± 14 s for the conventional algorithm. The CNN showed excellent performance for the simulated data compared with the conventional algorithm (median range of Dice scores CNN: [0.89–0.99], conventional algorithm: [0.84–0.94], p < 0.001, across all simulated vencs) and detected more aliased voxels in existing velocity aliasing data sets (median detected CNN: 159 voxels [31–605], conventional algorithm: 65 [7–417], p < 0.001). For controls, the CNN showed Dice scores of 0.98 [0.95–0.99] and 0.96 [0.87–0.99] for venc = 60 cm/s and 100 cm/s, respectively, while flow comparisons showed moderate‐excellent agreement. Conclusion Deep learning enabled fast and robust velocity anti‐aliasing in 4D‐flow MRI.
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Soulat G, Scott M, Allen BD, Avery R, Bonow RO, Malaisrie C, McCarthy P, Fedak P, Barker AJ, Markl M. Association of Regional Wall Shear Stress and Progressive Ascending Aorta Dilation in Bicuspid Aortic Valve. JACC. CARDIOVASCULAR IMAGING 2022; 15:33-42. [PMID: 34419402 PMCID: PMC8741630 DOI: 10.1016/j.jcmg.2021.06.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 06/02/2021] [Accepted: 06/07/2021] [Indexed: 01/03/2023]
Abstract
OBJECTIVES The aim of this study was to evaluate the role of wall shear stress (WSS) as a predictor of ascending aorta (AAo) growth at 5 years or greater follow-up. BACKGROUND Aortic 4-dimensional flow cardiac magnetic resonance (CMR) can quantify regions exposed to high WSS, a known stimulus for arterial wall dysfunction. However, its association with longitudinal changes in aortic dilation in patients with bicuspid aortic valve (BAV) is unknown. METHODS This retrospective study identified 72 patients with BAV (age 45 ± 12 years) who underwent CMR for surveillance of aortic dilation at baseline and ≥5 years of follow-up. Four-dimensional flow CMR analysis included the calculation of WSS heat maps to compare regional WSS in individual patients with population averages of healthy age- and sex-matched subjects (database of 136 controls). The relative areas of the AAo and aorta (in %) exposed to elevated WSS (outside the 95% CI of healthy population averages) were quantified. RESULTS At a median follow-up duration of 6.0 years, the mean AAo growth rate was 0.24 ± 0.20 mm/y. The fraction of the AAo exposed to elevated WSS at baseline was increased for patients with higher growth rates (>0.24 mm/y, n = 32) compared with those with growth rates <0.24 mm/y (19.9% [IQR: 10.2%-25.5%] vs 5.7% [IQR: 1.5%-21.3%]; P = 0.008). Larger areas of elevated WSS in the AAo and entire aorta were associated with higher rates of AAo dilation >0.24 mm/y (odds ratio: 1.51; 95% CI: 1.05-2.17; P = 0.026 and odds ratio: 1.70; 95% CI: 1.01-3.15; P = 0.046, respectively). CONCLUSIONS The area of elevated AAo WSS as assessed by 4-dimensional flow CMR identified BAV patients with higher rates of aortic dilation and thus might determine which patients require closer follow-up.
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Kalisz K, Scott M, Avery R, Sarnari R, Barker AJ, Carr J, Markl M, Allen BD. Cardiac Magnetic Resonance Imaging Feature Tracking Demonstrates Altered Biventricular Strain in Obese Subjects in the Absence of Clinically Apparent Cardiovascular Disease. J Thorac Imaging 2022; 37:W1-W2. [PMID: 32520847 PMCID: PMC7718327 DOI: 10.1097/rti.0000000000000539] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Mukherjee D, Barker AJ. Using Simulation-Based Active Learning Strategies for Teaching Biofluids Concepts. J Biomech Eng 2021; 143:121011. [PMID: 34729587 DOI: 10.1115/1.4052933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Indexed: 11/08/2022]
Abstract
Biofluids comprises a core topical domain for modern biomedical engineering education. Like other biomedical topic areas, biofluids education must address highly interdisciplinary and applied topics. Concept/problem-based active learning approaches can provide effective avenues to teach such diverse and applied topics. However, with the heterogeneity within biofluids topics across cellular, physiological, and/or extra-organismal scales, it is important to develop active learning content that enables students to explore concepts with appropriate context. This challenge is further complicated by the need to administer such content remotely (due to the Covid-19 pandemic). Here, we outline our design process and implementation experience for simulation-based active learning modules for a newly developed physiological biofluids course. We share the overall design approach, with two example cases of simulation-based concept exploration: (a) arterial Windkessel effects and lumped parameter hemodynamic analysis; and (b) curvature-induced helical flow in human aorta illustrated using four-dimensional (4D) flow magnetic resonance imaging (MRI). Evidence from student survey ratings, student comments and feedback, and monitoring student performance for course deliverables indicate positive student response toward these modules, and efficacy of the modules in enabling student learning. Based on our design and implementation experience, we argue that simulation-based approaches can enable active learning of biofluids through remote and online learning modalities.
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Fujiwara T, Berhane H, Scott MB, Englund EK, Schäfer M, Fonseca B, Berthusen A, Robinson JD, Rigsby CK, Browne LP, Markl M, Barker AJ. Segmentation of the Aorta and Pulmonary Arteries Based on 4D Flow MRI in the Pediatric Setting Using Fully Automated Multi-Site, Multi-Vendor, and Multi-Label Dense U-Net. J Magn Reson Imaging 2021; 55:1666-1680. [PMID: 34792835 DOI: 10.1002/jmri.27995] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 11/04/2021] [Accepted: 11/05/2021] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Automated segmentation using convolutional neural networks (CNNs) have been developed using four-dimensional (4D) flow magnetic resonance imaging (MRI). To broaden usability for congenital heart disease (CHD), training with multi-institution data is necessary. However, the performance impact of heterogeneous multi-site and multi-vendor data on CNNs is unclear. PURPOSE To investigate multi-site CNN segmentation of 4D flow MRI for pediatric blood flow measurement. STUDY TYPE Retrospective. POPULATION A total of 174 subjects across two sites (female: 46%; N = 38 healthy controls, N = 136 CHD patients). Participants from site 1 (N = 100), site 2 (N = 74), and both sites (N = 174) were divided into subgroups to conduct 10-fold cross validation (10% for testing, 90% for training). FIELD STRENGTH/SEQUENCE 3 T/1.5 T; retrospectively gated gradient recalled echo-based 4D flow MRI. ASSESSMENT Accuracy of the 3D CNN segmentations trained on data from single site (single-site CNNs) and data across both sites (multi-site CNN) were evaluated by geometrical similarity (Dice score, human segmentation as ground truth) and net flow quantification at the ascending aorta (Qs), main pulmonary artery (Qp), and their balance (Qp/Qs), between human observers, single-site and multi-site CNNs. STATISTICAL TESTS Kruskal-Wallis test, Wilcoxon rank-sum test, and Bland-Altman analysis. A P-value <0.05 was considered statistically significant. RESULTS No difference existed between single-site and multi-site CNNs for geometrical similarity in the aorta by Dice score (site 1: 0.916 vs. 0.915, P = 0.55; site 2: 0.906 vs. 0.904, P = 0.69) and for the pulmonary arteries (site 1: 0.894 vs. 0.895, P = 0.64; site 2: 0.870 vs. 0.869, P = 0.96). Qs site-1 medians were 51.0-51.3 mL/cycle (P = 0.81) and site-2 medians were 66.7-69.4 mL/cycle (P = 0.84). Qp site-1 medians were 46.8-48.0 mL/cycle (P = 0.97) and site-2 medians were 76.0-77.4 mL/cycle (P = 0.98). Qp/Qs site-1 medians were 0.87-0.88 (P = 0.97) and site-2 medians were 1.01-1.03 (P = 0.43). Bland-Altman analysis for flow quantification found equivalent performance. DATA CONCLUSION Multi-site CNN-based segmentation and blood flow measurement are feasible for pediatric 4D flow MRI and maintain performance of single-site CNNs. LEVEL OF EVIDENCE 3 TECHNICAL EFFICACY: Stage 2.
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Michelena HI, Corte AD, Evangelista A, Maleszewski JJ, Edwards WD, Roman MJ, Devereux RB, Fernández B, Asch FM, Barker AJ, Sierra-Galan LM, De Kerchove L, Fernandes SM, Fedak PWM, Girdauskas E, Delgado V, Abbara S, Lansac E, Prakash SK, Bissell MM, Popescu BA, Hope MD, Sitges M, Thourani VH, Pibarot P, Chandrasekaran K, Lancellotti P, Borger MA, Forrest JK, Webb J, Milewicz DM, Makkaar R, Leon MB, Sanders SP, Markl M, Ferrari VA, Roberts WC, Song JK, Blanke P, White CS, Siu S, Svensson LG, Braverman AC, Bavaria J, Sundt TM, El Khoury G, De Paulis R, Enriquez-Sarano M, Bax JJ, Otto CM, Schäfers HJ. International Consensus Statement on Nomenclature and Classification of the Congenital Bicuspid Aortic Valve and Its Aortopathy, for Clinical, Surgical, Interventional and Research Purposes. Radiol Cardiothorac Imaging 2021; 3:e200496. [PMID: 34505060 DOI: 10.1148/ryct.2021200496] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This International Consensus Classification and Nomenclature for the congenital bicuspid aortic valve condition recognizes 3 types of bicuspid valves: 1. The fused type (right-left cusp fusion, right-non-coronary cusp fusion and left-non-coronary cusp fusion phenotypes); 2. The 2-sinus type (latero-lateral and antero-posterior phenotypes); and 3. The partial-fusion (forme fruste) type. The presence of raphe and the symmetry of the fused type phenotypes are critical aspects to describe. The International Consensus also recognizes 3 types of bicuspid valve-associated aortopathy: 1. The ascending phenotype; 2. The root phenotype; and 3. Extended phenotypes. © 2021 Jointly between the RSNA, the European Association for Cardio-Thoracic Surgery, The Society of Thoracic Surgeons, and the American Association for Thoracic Surgery. The articles are identical except for minor stylistic and spelling differences in keeping with each journal's style. All rights reserved. Keywords: Bicuspid Aortic Valve, Aortopathy, Nomenclature, Classification.
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Mazzanti S, Manfredi G, Barker AJ, Antonietti M, Savateev A, Giusto P. Carbon Nitride Thin Films as All-In-One Technology for Photocatalysis. ACS Catal 2021. [DOI: 10.1021/acscatal.1c02909] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Maredia A, Guzzardi D, Aleinati M, Iqbal F, Khaira A, Madhu A, Wang X, Barker AJ, McCarthy PM, Fedak PWM, Greenway SC. Aorta-specific DNA methylation patterns in cell-free DNA from patients with bicuspid aortic valve-associated aortopathy. Clin Epigenetics 2021; 13:147. [PMID: 34321094 PMCID: PMC8320174 DOI: 10.1186/s13148-021-01137-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 07/19/2021] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND The dilation of the aorta that occurs as a consequence of a congenitally bicuspid aortic valve (BAV) is associated with a risk of dissection, aneurysm or rupture. With progressive aortopathy, surgery is often recommended, but current patient selection strategies have limitations. A blood-based assay to identify those who would most benefit from prophylactic surgery would be an important medical advance. In a proof-of-concept study, we sought to identify aorta-specific differentially methylated regions (DMRs) detectable in plasma cell-free DNA (cfDNA) obtained from patients undergoing surgery for BAV-associated aortopathy. METHODS We used bioinformatics and publicly available human methylomes to identify aorta-specific DMRs. We used data from 4D-flow cardiac magnetic resonance imaging to identify regions of elevated aortic wall shear stress (WSS) in patients with BAV-associated aortopathy undergoing surgery and correlated WSS regions with aortic tissue cell death assessed using TUNEL staining. Cell-free DNA was isolated from patient plasma, and levels of candidate DMRs were correlated with aortic diameter and aortic wall cell death. RESULTS Aortic wall cell death was not associated with maximal aortic diameter but was significantly associated with elevated WSS. We identified 24 candidate aorta-specific DMRs and selected 4 for further study. A DMR on chromosome 11 was specific for the aorta and correlated significantly with aortic wall cell death. Plasma levels of total and aorta-specific cfDNA did not correlate with aortic diameter. CONCLUSIONS In a cohort of patients undergoing surgery for BAV-associated aortopathy, elevated WSS created by abnormal flow hemodynamics was associated with increased aortic wall cell death which supports the use of aorta-specific cfDNA as a potential tool to identify aortopathy and stratify patient risk.
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Michelena HI, Della Corte A, Evangelista A, Maleszewski JJ, Edwards WD, Roman MJ, Devereux RB, Fernández B, Asch FM, Barker AJ, Sierra-Galan LM, De Kerchove L, Fernandes SM, Fedak PWM, Girdauskas E, Delgado V, Abbara S, Lansac E, Prakash SK, Bissell MM, Popescu BA, Hope MD, Sitges M, Thourani VH, Pibarot P, Chandrasekaran K, Lancellotti P, Borger MA, Forrest JK, Webb J, Milewicz DM, Makkar R, Leon MB, Sanders SP, Markl M, Ferrari VA, Roberts WC, Song JK, Blanke P, White CS, Siu S, Svensson LG, Braverman AC, Bavaria J, Sundt TM, El Khoury G, De Paulis R, Enriquez-Sarano M, Bax JJ, Otto CM, Schäfers HJ. Summary: international consensus statement on nomenclature and classification of the congenital bicuspid aortic valve and its aortopathy, for clinical, surgical, interventional and research purposes. Eur J Cardiothorac Surg 2021; 60:481-496. [PMID: 34292332 DOI: 10.1093/ejcts/ezab039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 01/15/2021] [Indexed: 11/12/2022] Open
Abstract
This International evidence-based nomenclature and classification consensus on the congenital bicuspid aortic valve and its aortopathy recognizes 3 types of bicuspid aortic valve: 1. Fused type, with 3 phenotypes: right-left cusp fusion, right-non cusp fusion and left-non cusp fusion; 2. 2-sinus type with 2 phenotypes: Latero-lateral and antero-posterior; and 3. Partial-fusion or forme fruste. This consensus recognizes 3 bicuspid-aortopathy types: 1. Ascending phenotype; root phenotype; and 3. extended phenotypes.
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Michelena HI, Della Corte A, Evangelista A, Maleszewski JJ, Edwards WD, Roman MJ, Devereux RB, Fernández B, Asch FM, Barker AJ, Sierra-Galan LM, De Kerchove L, Fernandes SM, Fedak PWM, Girdauskas E, Delgado V, Abbara S, Lansac E, Prakash SK, Bissell MM, Popescu BA, Hope MD, Sitges M, Thourani VH, Pibarot P, Chandrasekaran K, Lancellotti P, Borger MA, Forrest JK, Webb J, Milewicz DM, Makkar R, Leon MB, Sanders SP, Markl M, Ferrari VA, Roberts WC, Song JK, Blanke P, White CS, Siu S, Svensson LG, Braverman AC, Bavaria J, Sundt TM, El Khoury G, De Paulis R, Enriquez-Sarano M, Bax JJ, Otto CM, Schäfers HJ. International consensus statement on nomenclature and classification of the congenital bicuspid aortic valve and its aortopathy, for clinical, surgical, interventional and research purposes. J Thorac Cardiovasc Surg 2021; 162:e383-e414. [PMID: 34304896 DOI: 10.1016/j.jtcvs.2021.06.019] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This International Consensus Classification and Nomenclature for the congenital bicuspid aortic valve condition recognizes 3 types of bicuspid valves: 1. The fused type (right-left cusp fusion, right-non-coronary cusp fusion and left-non-coronary cusp fusion phenotypes); 2. The 2-sinus type (latero-lateral and antero-posterior phenotypes); and 3. The partial-fusion (forme fruste) type. The presence of raphe and the symmetry of the fused type phenotypes are critical aspects to describe. The International Consensus also recognizes 3 types of bicuspid valve-associated aortopathy: 1. The ascending phenotype; 2. The root phenotype; and 3. Extended phenotypes.
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Michelena HI, Della Corte A, Evangelista A, Maleszewski JJ, Edwards WD, Roman MJ, Devereux RB, Fernández B, Asch FM, Barker AJ, Sierra-Galan LM, De Kerchove L, Fernandes SM, Fedak PWM, Girdauskas E, Delgado V, Abbara S, Lansac E, Prakash SK, Bissell MM, Popescu BA, Hope MD, Sitges M, Thourani VH, Pibarot P, Chandrasekaran K, Lancellotti P, Borger MA, Forrest JK, Webb J, Milewicz DM, Makkar R, Leon MB, Sanders SP, Markl M, Ferrari VA, Roberts WC, Song JK, Blanke P, White CS, Siu S, Svensson LG, Braverman AC, Bavaria J, Sundt TM, Khoury GE, De Paulis R, Enriquez-Sarano M, Bax JJ, Otto CM, Schäfers HJ. Summary: International consensus statement on nomenclature and classification of the congenital bicuspid aortic valve and its aortopathy, for clinical, surgical, interventional, and research purposes. J Thorac Cardiovasc Surg 2021; 162:781-797. [PMID: 34304894 DOI: 10.1016/j.jtcvs.2021.05.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 01/05/2021] [Indexed: 11/30/2022]
Abstract
This International evidence-based nomenclature and classification consensus on the congenital bicuspid aortic valve and its aortopathy recognizes 3 types of bicuspid aortic valve: 1. Fused type, with 3 phenotypes: right-left cusp fusion, right-non cusp fusion and left-non cusp fusion; 2. 2-sinus type with 2 phenotypes: Latero-lateral and antero-posterior; and 3. Partial-fusion or forme fruste. This consensus recognizes 3 bicuspid-aortopathy types: 1. Ascending phenotype; root phenotype; and 3. extended phenotypes.
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Michelena HI, Della Corte A, Evangelista A, Maleszewski JJ, Edwards WD, Roman MJ, Devereux RB, Fernández B, Asch FM, Barker AJ, Sierra-Galan LM, De Kerchove L, Fernandes SM, Fedak PWM, Girdauskas E, Delgado V, Abbara S, Lansac E, Prakash SK, Bissell MM, Popescu BA, Hope MD, Sitges M, Thourani VH, Pibarot P, Chandrasekaran K, Lancellotti P, Borger MA, Forrest JK, Webb J, Milewicz DM, Makkar R, Leon MB, Sanders SP, Markl M, Ferrari VA, Roberts WC, Song JK, Blanke P, White CS, Siu S, Svensson LG, Braverman AC, Bavaria J, Sundt TM, El Khoury G, De Paulis R, Enriquez-Sarano M, Bax JJ, Otto CM, Schäfers HJ. International consensus statement on nomenclature and classification of the congenital bicuspid aortic valve and its aortopathy, for clinical, surgical, interventional and research purposes. Eur J Cardiothorac Surg 2021; 60:448-476. [PMID: 34293102 DOI: 10.1093/ejcts/ezab038] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
This International Consensus Classification and Nomenclature for the congenital bicuspid aortic valve condition recognizes 3 types of bicuspid valves: 1. The fused type (right-left cusp fusion, right-non-coronary cusp fusion and left-non-coronary cusp fusion phenotypes); 2. The 2-sinus type (latero-lateral and antero-posterior phenotypes); and 3. The partial-fusion (forme fruste) type. The presence of raphe and the symmetry of the fused type phenotypes are critical aspects to describe. The International Consensus also recognizes 3 types of bicuspid valve-associated aortopathy: 1. The ascending phenotype; 2. The root phenotype; and 3. Extended phenotypes.
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Michelena HI, Della Corte A, Evangelista A, Maleszewski JJ, Edwards WD, Roman MJ, Devereux RB, Fernández B, Asch FM, Barker AJ, Sierra-Galan LM, De Kerchove L, Fernandes SM, Fedak PWM, Girdauskas E, Delgado V, Abbara S, Lansac E, Prakash SK, Bissell MM, Popescu BA, Hope MD, Sitges M, Thourani VH, Pibarot P, Chandrasekaran K, Lancellotti P, Borger MA, Forrest JK, Webb J, Milewicz DM, Makkar R, Leon MB, Sanders SP, Markl M, Ferrari VA, Roberts WC, Song JK, Blanke P, White CS, Siu S, Svensson LG, Braverman AC, Bavaria J, Sundt TM, El Khoury G, De Paulis R, Enriquez-Sarano M, Bax JJ, Otto CM, Schäfers HJ. International Consensus Statement on Nomenclature and Classification of the Congenital Bicuspid Aortic Valve and Its Aortopathy, for Clinical, Surgical, Interventional and Research Purposes. Ann Thorac Surg 2021; 112:e203-e235. [PMID: 34304860 DOI: 10.1016/j.athoracsur.2020.08.119] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 08/30/2020] [Indexed: 01/17/2023]
Abstract
This International Consensus Classification and Nomenclature for the congenital bicuspid aortic valve condition recognizes 3 types of bicuspid valves: 1. The fused type (right-left cusp fusion, right-non-coronary cusp fusion and left-non-coronary cusp fusion phenotypes); 2. The 2-sinus type (latero-lateral and antero-posterior phenotypes); and 3. The partial-fusion (forme fruste) type. The presence of raphe and the symmetry of the fused type phenotypes are critical aspects to describe. The International Consensus also recognizes 3 types of bicuspid valve-associated aortopathy: 1. The ascending phenotype; 2. The root phenotype; and 3. Extended phenotypes.
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Chen V, Barker AJ, Golan R, Scott MB, Huh H, Wei Q, Sojoudi A, Markl M. Effect of age and sex on fully automated deep learning assessment of left ventricular function, volumes, and contours in cardiac magnetic resonance imaging. Int J Cardiovasc Imaging 2021; 37:3539-3547. [PMID: 34185211 DOI: 10.1007/s10554-021-02326-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 06/24/2021] [Indexed: 01/03/2023]
Abstract
Deep learning algorithms for left ventricle (LV) segmentation are prone to bias towards the training dataset. This study assesses sex- and age-dependent performance differences when using deep learning for automatic LV segmentation. Retrospective analysis of 100 healthy subjects undergoing cardiac MRI from 2012 to 2018, with 10 men and women in the following age groups: 18-30, 31-40, 41-50, 51-60, and 61-80 years old. Subjects underwent 1.5 T, 2D CINE SSFP MRI. 35 pathologic cases from local clinical exams and the SCMR 2015 consensus contours dataset were also analyzed. A fully convolutional network (FCN) similar to U-Net trained on the U.K. Biobank was used to automatically segment LV endocardial and epicardial contours. FCN and manual segmentation were compared using Dice metrics and measurements of end-diastolic volume (EDV), end-systolic volume (ESV), mass (LVM), and ejection fraction (LVEF). Paired t-tests and linear regressions were used to analyze measurement differences with respect to sex and age. Dice metrics (median ± IQR) for n = 135 cases were 0.94 ± 0.04/0.87 ± 0.10 (ED endocardium/ES endocardium). Measurement biases (mean ± SD) among the healthy cohort were - 0.3 ± 10.1 mL for EDV, - 6.7 ± 9.6 mL for ESV, 4.6 ± 6.4% for LVEF, and - 2.2 ± 11.0 g for LVM; biases were independent of sex and age. Biases among the 35 pathologic cases were 0.1 ± 19 mL for EDV, - 4.8 ± 19 mL for ESV, 2.0 ± 7.6% for LVEF, and 1.0 ± 20 g for LVM. In conclusion, automatic segmentation by the Biobank-trained FCN was independent of age and sex. Improvements in end-systolic basal slice detection are needed to decrease bias and improve precision in ESV and LVEF.
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Melena I, Bjornstad P, Schäfer M, Hunter KS, Barker AJ, Baumgartner A, Chung L, Wiromrat P, Truong U, Reusch JEB, Nadeau KJ. Serum copeptin and NT-proBNP is associated with central aortic stiffness and flow hemodynamics in adolescents with type 1 diabetes: A pilot study. J Diabetes Complications 2021; 35:107883. [PMID: 33712333 PMCID: PMC8957479 DOI: 10.1016/j.jdiacomp.2021.107883] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 01/10/2021] [Accepted: 01/29/2021] [Indexed: 01/17/2023]
Abstract
AIMS Cardiovascular disease (CVD) is the major cause of mortality in type 1 diabetes (T1D). Biomarkers, N-terminal pro-brain natriuretic peptide (NT-proBNP) and copeptin have been linked with measures of CVD, but their relationship in adolescents with T1D remains incompletely understood. Accordingly, we examined the associations between NT-proBNP and copeptin and hemodynamic markers of central aortic stiffness in adolescents with T1D. METHODS In this pilot study, forty-nine pubertal adolescents with T1D (mean age 17 ± 2 years, median [Q1-Q3] Tanner Stage 5 [5, 5] and HbA1c 8.5 ± 1.5%), from the EMERALD study, were assessed for copeptin and NT-proBNP, and indices of central aortic stiffness non-invasively assessed by MRI. Pearson correlations and generalized linear regression models, adjusting for confounders, were applied to examine the relationships between biomarkers and vascular measures. RESULTS Copeptin correlated independently with both ascending aortic (AA) (β ± SE: -4.28 ± 1.87, p = 0.03) and descending aortic (DA) relative area change (RAC) (-3.41 ± 1.55, p = 0.04). NT-proBNP was independently associated with DA time-averaged wall shear stress (WSSTA) (0.87 ± 0.25, p = 0.001) and DA maximum wall shear stress (WSSmax) (2.45 ± 1.00, p = 0.02). CONCLUSIONS Serum copeptin and NT-proBNP may be associated with central aortic stiffness and elevated WSS in youth with T1D, potentially offering a non-invasive way to identify and monitor the development of early CVD in an at-risk population.
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