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Craine A, Scott A, Desai D, Kligerman S, Adler E, Kim NH, Alshawabkeh L, Contijoch F. 3D regional evaluation of right ventricular myocardial work from cineCT. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.07.30.24311094. [PMID: 39132470 PMCID: PMC11312672 DOI: 10.1101/2024.07.30.24311094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
Background Regional myocardial work (MW) is not measured in the right ventricle (RV) due to a lack of high spatial resolution regional strain (RS) estimates throughout the ventricle. We present a cineCT-based approach to evaluate regional RV performance and demonstrate its ability to phenotype three complex populations: end-stage LV failure (HF), chronic thromboembolic pulmonary hypertension (CTEPH), and repaired tetralogy of Fallot (rTOF). Methods 49 patients (19 HF, 11 CTEPH, 19 rTOF) underwent cineCT and right heart catheterization (RHC). RS was estimated from full-cycle ECG-gated cineCT and combined with RHC pressure waveforms to create regional pressure-strain loops; endocardial MW was measured as the loop area. Detailed, 3D mapping of RS and MW enabled spatial visualization of strain and work strength, and phenotyping of patients. Results HF patients demonstrated more overall impaired strain and work compared to the CTEPH and rTOF cohorts. For example, the HF patients had more akinetic areas (median: 9%) than CTEPH (median: <1%, p=0.02) and rTOF (median: 1%, p<0.01) and performed more low work (median: 69%) than the rTOF cohort (median: 38%, p<0.01). The CTEPH cohort had more impairment in the septal wall; <1% of the free wall and 16% of the septal wall performed negative work. The rTOF cohort demonstrated a wide distribution of strain and work, ranging from hypokinetic to hyperkinetic strain and low to medium-high work. Impaired strain (-0.15≤RS) and negative work were strongly-to-very strongly correlated with RVEF (R=-0.89, p<0.01; R=-0.70, p<0.01 respectively), while impaired work (MW≤5 mmHg) was moderately correlated with RVEF (R=-0.53, p<0.01). Conclusions Regional RV MW maps can be derived from clinical CT and RHC studies and can provide patient-specific phenotyping of RV function in complex heart disease patients. Clinical Perspective Evaluating regional variations in right ventricular (RV) performance can be challenging, particularly in patients with significant impairments due to the need for 3D spatial coverage with high spatial resolution. ECG-gated cineCT can fully visualize the RV and be used to quantify regional strain with high spatial resolution. However, strain is influenced by loading conditions. Myocardial work (MW) - measured clinically derived as the ventricular pressure-strain loop area - is considered a more comprehensive metric due to its independence of preload and afterload. In this study, we sought to develop regional RV myocardial work (MW) assessments in 3D with high spatial resolution by combining cineCT-derived regional strain with RV pressure waveforms from right heart catheterization (RHC). We developed our method using data from three clinical cohorts who routinely undergo cineCT and RHC: patients in heart failure, patients with chronic thromboembolic pulmonary hypertension, and adults with repaired tetralogy of Fallot.We demonstrate that regional strain and work provide different perspectives on RV performance. While strain can be used to evaluate apparent function, similar profiles of RV strain can lead to different MW estimates. Specifically, MW integrates apparent strain with measures of afterload, and timing information helps to account for dyssynchrony. As a result, CT-based assessment of RV MW appears to be a useful new metric for the care of patients with dysfunction.
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Craine A, Krishnamurthy A, Villongco CT, Vincent K, Krummen DE, Narayan SM, Kerckhoffs RCP, Omens JH, Contijoch F, McCulloch AD. Successful Cardiac Resynchronization Therapy Reduces Negative Septal Work in Patient-Specific Models of Dyssynchronous Heart Failure. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.13.593804. [PMID: 38798676 PMCID: PMC11118505 DOI: 10.1101/2024.05.13.593804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
In patients with dyssynchronous heart failure (DHF), cardiac conduction abnormalities cause the regional distribution of myocardial work to be non-homogeneous. Cardiac resynchronization therapy (CRT) using an implantable, programmed biventricular pacemaker/defibrillator, can improve the synchrony of contraction between the right and left ventricles in DHF, resulting in reduced morbidity and mortality and increased quality of life. Since regional work depends on wall stress, which cannot be measured in patients, we used computational methods to investigate regional work distributions and their changes after CRT. We used three-dimensional multi-scale patient-specific computational models parameterized by anatomic, functional, hemodynamic, and electrophysiological measurements in eight patients with heart failure and left bundle branch block (LBBB) who received CRT. To increase clinical translatability, we also explored whether streamlined computational methods provide accurate estimates of regional myocardial work. We found that CRT increased global myocardial work efficiency with significant improvements in non-responders. Reverse ventricular remodeling after CRT was greatest in patients with the highest heterogeneity of regional work at baseline, however the efficacy of CRT was not related to the decrease in overall work heterogeneity or to the reduction in late-activated regions of high myocardial work. Rather, decreases in early-activated regions of myocardium performing negative myocardial work following CRT best explained patient variations in reverse remodeling. These findings were also observed when regional myocardial work was estimated using ventricular pressure as a surrogate for myocardial stress and changes in endocardial surface area as a surrogate for strain. These new findings suggest that CRT promotes reverse ventricular remodeling in human dyssynchronous heart failure by increasing regional myocardial work in early-activated regions of the ventricles, where dyssynchrony is specifically associated with hypoperfusion, late systolic stretch, and altered metabolic activity and that measurement of these changes can be performed using streamlined approaches.
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Affiliation(s)
- Amanda Craine
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA
| | - Adarsh Krishnamurthy
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA
- Department of Mechanical Engineering, Iowa State University, Ames, IA 50011, USA
| | | | - Kevin Vincent
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA
| | - David E. Krummen
- Department of Medicine (Cardiology), University of California San Diego, CA 92093, USA
- US Department of Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA
| | | | - Roy C. P. Kerckhoffs
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA
| | - Jeffrey H. Omens
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA
- Department of Medicine (Cardiology), University of California San Diego, CA 92093, USA
| | - Francisco Contijoch
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA
- Department of Radiology, University of California San Diego, CA 92093, USA
| | - Andrew D. McCulloch
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA
- Department of Medicine (Cardiology), University of California San Diego, CA 92093, USA
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Scott A, Chen Z, Kligerman S, Kim P, Tran H, Adler E, Narezkina A, Contijoch F. Regional Strain of Right Ventricle From Computed Tomography Improves Risk Stratification of Right Ventricle Failure. ASAIO J 2024; 70:358-364. [PMID: 38166039 PMCID: PMC11062830 DOI: 10.1097/mat.0000000000002123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2024] Open
Abstract
Patients who undergo implantation of a left ventricular assist device (LVAD) are at a high risk for right ventricular failure (RVF), presumably due to poor right ventricular (RV) function before surgery. Cine computerized tomography (cineCT) can be used to evaluate RV size, function, and endocardial strain. However, CT-based strain measures in patients undergoing workup for LVAD implantation have not been evaluated. We quantified RV strain in the free wall (FW) and septal wall (SW) in patients with end-stage heart failure using cineCT. Compared to controls, both FW and SW strains were significantly impaired in heart failure patients. The difference between FW and SW strains predicted RV failure after LVAD implantation (area-under-the curve [AUC] = 0.82). Cine CT strain can be combined with RV volumetry to risk-stratify patients. In our study, patients with preserved RV volumes and poor strain had a higher rate of RV failure (57%), than those with preserved volume and preserved strain (0%). This suggests that CT could improve risk stratification of patients receiving LVADs and that strain metrics were particularly useful in risk-stratifying patients with preserved RV volumes.
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Affiliation(s)
- Anderson Scott
- Shu Chien-Gene Lay Department of Bioengineering, UC San Diego, La Jolla CA
| | - Zhennong Chen
- Shu Chien-Gene Lay Department of Bioengineering, UC San Diego, La Jolla CA
| | - Seth Kligerman
- Department of Radiology, National Jewish Health, Denver, CO
| | - Paul Kim
- Division of Cardiology, Department of Medicine, UC San Diego, La Jolla CA
| | - Hao Tran
- Division of Cardiology, Department of Medicine, UC San Diego, La Jolla CA
| | - Eric Adler
- Division of Cardiology, Department of Medicine, UC San Diego, La Jolla CA
| | - Anna Narezkina
- Division of Cardiology, Department of Medicine, UC San Diego, La Jolla CA
| | - Francisco Contijoch
- Shu Chien-Gene Lay Department of Bioengineering, UC San Diego, La Jolla CA
- Department of Radiology, UC San Diego, La Jolla CA
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Chen Z, Contijoch F, Kahn AM, Kligerman S, Narayan HK, Manohar A, McVeigh E. Myocardial Regional Shortening from 4D Cardiac CT Angiography for the Detection of Left Ventricular Segmental Wall Motion Abnormality. Radiol Cardiothorac Imaging 2023; 5:e220134. [PMID: 37124646 PMCID: PMC10141330 DOI: 10.1148/ryct.220134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 01/22/2023] [Accepted: 01/30/2023] [Indexed: 05/02/2023]
Abstract
Purpose To investigate whether endocardial regional shortening computed from four-dimensional (4D) CT angiography (RSCT) can be used as a decision classifier to detect the presence of left ventricular (LV) wall motion abnormalities (WMAs). Materials and Methods One hundred electrocardiographically gated cardiac 4D CT studies (mean age, 59 years ± 14 [SD]; 61 male patients) conducted between April 2018 and December 2020 were retrospectively evaluated. Three experts labeled LV wall motion in each of the 16 American Heart Association (AHA) segments as normal or abnormal; they also measured peak RSCT across one heartbeat in each segment. The data set was split evenly into training and validation groups. During training, interchangeability of RSCT thresholding with experts to detect WMA was assessed using the individual equivalence index (γ), and an optimal threshold of the peak RSCT (RSCT*) that achieved maximum agreement was identified. RSCT* was then validated using the validation group, and the effect of AHA segment-specific thresholds was evaluated. Agreement was assessed using κ statistics. Results The optimal threshold, RSCT* of -0.19, when applied to all AHA segments, led to high agreement (agreement rate = 92.17%, κ = 0.82) and interchangeability with experts (γ = -2.58%). The same RSCT* also achieved high agreement in the validation group (agreement rate = 90.29%, κ = 0.76, γ = -0.38%). The use of AHA segment-specific thresholds (range: 0.16 to -0.23 across AHA segments) slightly improved agreement (1.79% increase). Conclusion RSCT thresholding was interchangeable with expert visual analysis in detecting segmental WMA from 4D CT and may be used as an objective decision classifier.Keywords: CT, Left Ventricle, Regional Endocardial Shortening, Wall Motion Abnormality Supplemental material is available for this article. © RSNA, 2023.
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Affiliation(s)
- Zhennong Chen
- From the Departments of Bioengineering (Z.C., F.C., E.M.) and
Mechanical and Aerospace Engineering (A.M.), UC San Diego School of Engineering,
La Jolla, Calif; and Departments of Radiology (F.C., S.K., E.M.), Cardiology
(A.M.K., E.M.), and Pediatrics (H.K.N.), UC San Diego School of Medicine, 9452
Medical Dr, La Jolla, CA 92037
| | - Francisco Contijoch
- From the Departments of Bioengineering (Z.C., F.C., E.M.) and
Mechanical and Aerospace Engineering (A.M.), UC San Diego School of Engineering,
La Jolla, Calif; and Departments of Radiology (F.C., S.K., E.M.), Cardiology
(A.M.K., E.M.), and Pediatrics (H.K.N.), UC San Diego School of Medicine, 9452
Medical Dr, La Jolla, CA 92037
| | - Andrew M. Kahn
- From the Departments of Bioengineering (Z.C., F.C., E.M.) and
Mechanical and Aerospace Engineering (A.M.), UC San Diego School of Engineering,
La Jolla, Calif; and Departments of Radiology (F.C., S.K., E.M.), Cardiology
(A.M.K., E.M.), and Pediatrics (H.K.N.), UC San Diego School of Medicine, 9452
Medical Dr, La Jolla, CA 92037
| | - Seth Kligerman
- From the Departments of Bioengineering (Z.C., F.C., E.M.) and
Mechanical and Aerospace Engineering (A.M.), UC San Diego School of Engineering,
La Jolla, Calif; and Departments of Radiology (F.C., S.K., E.M.), Cardiology
(A.M.K., E.M.), and Pediatrics (H.K.N.), UC San Diego School of Medicine, 9452
Medical Dr, La Jolla, CA 92037
| | - Hari K. Narayan
- From the Departments of Bioengineering (Z.C., F.C., E.M.) and
Mechanical and Aerospace Engineering (A.M.), UC San Diego School of Engineering,
La Jolla, Calif; and Departments of Radiology (F.C., S.K., E.M.), Cardiology
(A.M.K., E.M.), and Pediatrics (H.K.N.), UC San Diego School of Medicine, 9452
Medical Dr, La Jolla, CA 92037
| | - Ashish Manohar
- From the Departments of Bioengineering (Z.C., F.C., E.M.) and
Mechanical and Aerospace Engineering (A.M.), UC San Diego School of Engineering,
La Jolla, Calif; and Departments of Radiology (F.C., S.K., E.M.), Cardiology
(A.M.K., E.M.), and Pediatrics (H.K.N.), UC San Diego School of Medicine, 9452
Medical Dr, La Jolla, CA 92037
| | - Elliot McVeigh
- From the Departments of Bioengineering (Z.C., F.C., E.M.) and
Mechanical and Aerospace Engineering (A.M.), UC San Diego School of Engineering,
La Jolla, Calif; and Departments of Radiology (F.C., S.K., E.M.), Cardiology
(A.M.K., E.M.), and Pediatrics (H.K.N.), UC San Diego School of Medicine, 9452
Medical Dr, La Jolla, CA 92037
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Scott A, Kligerman S, Hernandez DH, Kim P, Tran H, Pretorius V, Adler E, Contijoch F. Preoperative Computed Tomography Assessment of Risk of Right Ventricle Failure After Left Ventricular Assist Device Placement. ASAIO J 2023; 69:69-75. [PMID: 36583772 PMCID: PMC10684273 DOI: 10.1097/mat.0000000000001710] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Identification of patients who are at a high risk for right ventricular failure (RVF) after left ventricular assist device (LVAD) implantation is of critical importance. Conventional tools for predicting RVF, including two-dimensional echocardiography, right heart catheterization (RHC), and clinical parameters, generally have limited sensitivity and specificity. We retrospectively examined the ability of computed tomography (CT) ventricular volume measures to identify patients who experienced RVF after LVAD implantation. Between September 2017 and November 2021, 92 patients underwent LVAD surgery at our institution. Preoperative CT-derived ventricular volumes were obtained in 20 patients. Patients who underwent CT evaluation had a similar demographics and rate of RVF after LVAD as patients who did not undergo cardiac CT imaging. In the study cohort, seven of 20 (35%) patients experienced RVF (2 unplanned biventricular assist device, 5 prolonged inotropic support). Computed tomography-derived right ventricular end-diastolic and end-systolic volume indices were the strongest predictors of RVF compared with demographic, echocardiographic, and RHC data with areas under the receiver operating curve of 0.79 and 0.76, respectively. Computed tomography volumetric assessment of RV size can be performed in patients evaluated for LVAD treatment. RV measures of size provide a promising means of pre-LVAD assessment for postoperative RV failure.
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Affiliation(s)
- Anderson Scott
- Department of Bioengineering, UC San Diego, 9500 Gilman Drive, La Jolla CA, United States
| | - Seth Kligerman
- Department of Radiology, UC San Diego, 9500 Gilman Drive, La Jolla CA, United States
| | | | - Paul Kim
- Department of Medicine, UC San Diego, 9500 Gilman Drive, La Jolla CA, United States
| | - Hao Tran
- Department of Medicine, UC San Diego, 9500 Gilman Drive, La Jolla CA, United States
| | - Victor Pretorius
- Department of Surgery, UC San Diego, 9500 Gilman Drive, La Jolla CA, United States
| | - Eric Adler
- Department of Medicine, UC San Diego, 9500 Gilman Drive, La Jolla CA, United States
| | - Francisco Contijoch
- Department of Bioengineering, UC San Diego, 9500 Gilman Drive, La Jolla CA, United States
- Department of Radiology, UC San Diego, 9500 Gilman Drive, La Jolla CA, United States
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Li H, Chen Z, Kahn AM, Kligerman S, Narayan HK, Contijoch FJ. Deep learning automates detection of wall motion abnormalities via measurement of longitudinal strain from ECG-gated CT images. Front Cardiovasc Med 2022; 9:1009445. [PMID: 36588550 PMCID: PMC9797833 DOI: 10.3389/fcvm.2022.1009445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 11/28/2022] [Indexed: 12/16/2022] Open
Abstract
Introduction 4D cardiac CT (cineCT) is increasingly used to evaluate cardiac dynamics. While echocardiography and CMR have demonstrated the utility of longitudinal strain (LS) measures, measuring LS from cineCT currently requires reformatting the 4D dataset into long-axis imaging planes and delineating the endocardial boundary across time. In this work, we demonstrate the ability of a recently published deep learning framework to automatically and accurately measure LS for detection of wall motion abnormalities (WMA). Methods One hundred clinical cineCT studies were evaluated by three experienced cardiac CT readers to identify whether each AHA segment had a WMA. Fifty cases were used for method development and an independent group of 50 were used for testing. A previously developed convolutional neural network was used to automatically segment the LV bloodpool and to define the 2, 3, and 4 CH long-axis imaging planes. LS was measured as the perimeter of the bloodpool for each long-axis plane. Two smoothing approaches were developed to avoid artifacts due to papillary muscle insertion and texture of the endocardial surface. The impact of the smoothing was evaluated by comparison of LS estimates to LV ejection fraction and the fractional area change of the corresponding view. Results The automated, DL approach successfully analyzed 48/50 patients in the training cohort and 47/50 in the testing cohort. The optimal LS cutoff for identification of WMA was -21.8, -15.4, and -16.6% for the 2-, 3-, and 4-CH views in the training cohort. This led to correct labeling of 85, 85, and 83% of 2-, 3-, and 4-CH views, respectively, in the testing cohort. Per-study accuracy was 83% (84% sensitivity and 82% specificity). Smoothing significantly improved agreement between LS and fractional area change (R 2: 2 CH = 0.38 vs. 0.89 vs. 0.92). Conclusion Automated LV blood pool segmentation and long-axis plane delineation via deep learning enables automatic LS assessment. LS values accurately identify regional wall motion abnormalities and may be used to complement standard visual assessments.
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Affiliation(s)
- Hui Li
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, United States
| | - Zhennong Chen
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, United States
| | - Andrew M. Kahn
- Department of Medicine, Division of Cardiovascular Medicine, University of California, San Diego, La Jolla, CA, United States
| | - Seth Kligerman
- Department of Radiology, University of California, San Diego, La Jolla, CA, United States
| | - Hari K. Narayan
- Department of Pediatrics, University of California, San Diego, La Jolla, CA, United States
| | - Francisco J. Contijoch
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, United States
- Department of Radiology, University of California, San Diego, La Jolla, CA, United States
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Manohar A, Colvert GM, Ortuño JE, Chen Z, Yang J, Colvert BT, Bandettini WP, Chen MY, Ledesma-Carbayo MJ, McVeigh ER. Regional left ventricular endocardial strains estimated from low-dose 4DCT: Comparison with cardiac magnetic resonance feature tracking. Med Phys 2022; 49:5841-5854. [PMID: 35751864 PMCID: PMC9474637 DOI: 10.1002/mp.15818] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 05/31/2022] [Accepted: 06/10/2022] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND Estimates of regional left ventricular (LV) strains provide additional information to global function parameters such as ejection fraction (EF) and global longitudinal strain (GLS) and are more sensitive in detecting abnormal regional cardiac function. The accurate and reproducible assessment of regional cardiac function has implications in the management of various cardiac diseases such as heart failure, myocardial ischemia, and dyssynchrony. PURPOSE To develop a method that yields highly reproducible, high-resolution estimates of regional endocardial strains from 4DCT images. METHODS A method for estimating regional LV endocardial circumferential( ε c c ) $( {{\epsilon }_{cc}} )$ and longitudinal (ε l l ${\epsilon }_{ll}$ ) strains from 4DCT was developed. Point clouds representing the LV endocardial surface were extracted for each time frame of the cardiac cycle from 4DCT images. 3D deformation fields across the cardiac cycle were obtained by registering the end diastolic point cloud to each subsequent point cloud in time across the cardiac cycle using a 3D point-set registration technique. From these deformation fields,ε c c and ε l l ${\epsilon }_{cc}\ {\rm{and\ }}{\epsilon }_{ll}$ were estimated over the entire LV endocardial surface by fitting an affine transformation with maximum likelihood estimation. The 4DCT-derived strains were compared with strains estimated in the same subjects by cardiac magnetic resonance (CMR); twenty-four subjects had CMR scans followed by 4DCT scans acquired within a few hours. Regional LV circumferential and longitudinal strains were estimated from the CMR images using a commercially available feature tracking software (cvi42). Global circumferential strain (GCS) and global longitudinal strain (GLS) were calculated as the mean of the regional strains across the entire LV for both modalities. Pearson correlation coefficients and Bland-Altman analyses were used for comparisons. Intraclass correlation coefficients (ICC) were used to assess the inter- and intraobserver reproducibility of the 4DCT-derived strains. RESULTS The 4DCT-derived regional strains correlated well with the CMR-derived regional strains (ε c c ${\epsilon }_{cc}$ : r = 0.76, p < 0.001;ε l l ${\epsilon }_{ll}$ : r = 0.64, p < 0.001). A very strong correlation was found between 4DCT-derived GCS and 4DCT-derived EF (r = -0.96; p < 0.001). The 4DCT-derived strains were also highly reproducible, with very low inter- and intraobserver variability (intraclass correlation coefficients in the range of [0.92, 0.99]). CONCLUSIONS We have developed a novel method to estimate high-resolution regional LV endocardial circumferential and longitudinal strains from 4DCT images. Except for the definition of the mitral valve and LV outflow tract planes, the method is completely user independent, thus yielding highly reproducible estimates of endocardial strain. The 4DCT-derived strains correlated well with those estimated using a commercial CMR feature tracking software. The promising results reported in this study highlight the potential utility of 4DCT in the precise assessment of regional cardiac function for the management of cardiac disease.
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Affiliation(s)
- Ashish Manohar
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California, USA
| | - Gabrielle M Colvert
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
| | - Juan E Ortuño
- Biomedical Research Networking Centre in Bioengineering, Biomaterials and Nanomedicine, Madrid, Spain
- Biomedical Image Technologies Laboratory, ETSI Telecomunicación, Universidad Politécnica de Madrid, Madrid, Spain
| | - Zhennong Chen
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
| | - James Yang
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
| | - Brendan T Colvert
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
| | - W Patricia Bandettini
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Marcus Y Chen
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - María J Ledesma-Carbayo
- Biomedical Research Networking Centre in Bioengineering, Biomaterials and Nanomedicine, Madrid, Spain
- Biomedical Image Technologies Laboratory, ETSI Telecomunicación, Universidad Politécnica de Madrid, Madrid, Spain
| | - Elliot R McVeigh
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
- Department of Radiology, University of California San Diego, La Jolla, California, USA
- Department of Medicine, Cardiovascular Division, University of California San Diego, La Jolla, California, USA
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8
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Rigolli M, Reeves R, Smitson C, Yang J, Alotaibi M, Mahmud E, Malhotra A, Contijoch F. Right Ventricular and Pulmonary Computed Tomography Assessments in Paradoxical Low-Flow Low-Gradient Aortic Stenosis Undergoing Transcatheter Aortic Valve Replacement. STRUCTURAL HEART : THE JOURNAL OF THE HEART TEAM 2022; 6:100014. [PMID: 36212028 PMCID: PMC9541583 DOI: 10.1016/j.shj.2022.100014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 11/04/2021] [Accepted: 11/09/2021] [Indexed: 06/04/2023]
Abstract
Background Patients with paradoxical low-flow low-gradient aortic stenosis (pLFLG-AS) have high mortality and high degree of TAVR futility. Computed tomography (CT) enables accurate simultaneous right ventricular (RV) and parenchymal lung disease evaluation which may provide useful objective markers of AS severity, concomitant pulmonary comorbidities, and transcatheter aortic valve replacement (TAVR) improvement. However, the prevalence of RV dysfunction and its association with pulmonary disease in pLFLG-AS is unknown. The study objective was to test the hypothesis that pLFLG-AS patients undergoing TAVR have decreased RV function without significant parenchymal lung disease. Methods Between August 2016 and March 2020, 194 consecutive AS patients completed high-resolution computed tomography (CT) imaging for TAVR evaluation. Subjects were stratified based on echocardiographic criteria as the study group, pLFLG (n=27), and two consecutive control groups: classic severe, normal-flow, high-gradient (n=27) and normal-flow, low-gradient (NFLG) (n=27) AS. Blinded biventricular function and lung parenchymal disease assessments were obtained by high-resolution CT imaging. Results Patient demographics were similar between groups. pLFLG-AS had lower RV ejection fraction (49±10%) compared to both classic severe (58±7%, p<0.001) and NFLG AS (55±65%, p=0.02). There were no significant differences on lung emphysema (p=0.19), air fraction (p=0.58), and pulmonary disease presence (p=0.94) and severity (p=0.67) between groups. Conclusion pLFLG-AS patients have lower RV ejection fraction, than classic severe and normal-flow low-gradient AS patients in the absence of significant parenchymal lung disease on CT imaging. These findings support the direct importance of RV function in the pathophysiology of aortic valve disease.
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Affiliation(s)
- Marzia Rigolli
- Department of Bioengineering, UC San Diego, La Jolla, California, USA
| | - Ryan Reeves
- Division of Cardiovascular Medicine, Department of Medicine, UC San Diego, La Jolla, California, USA
| | - Christopher Smitson
- Division of Cardiovascular Medicine, Department of Medicine, UC San Diego, La Jolla, California, USA
| | - Jenny Yang
- Division of Pulmonology, Critical Care, and Sleep Medicine, Department of Medicine, UC San Diego, La Jolla, California, USA
| | - Mona Alotaibi
- Division of Pulmonology, Critical Care, and Sleep Medicine, Department of Medicine, UC San Diego, La Jolla, California, USA
| | - Ehtisham Mahmud
- Division of Cardiovascular Medicine, Department of Medicine, UC San Diego, La Jolla, California, USA
| | - Atul Malhotra
- Division of Pulmonology, Critical Care, and Sleep Medicine, Department of Medicine, UC San Diego, La Jolla, California, USA
| | - Francisco Contijoch
- Department of Bioengineering, UC San Diego, La Jolla, California, USA
- Department of Radiology, UC San Diego, La Jolla, California, USA
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Gupta K, Sekhar N, Vigneault DM, Scott AR, Colvert B, Craine A, Raghavan A, Contijoch FJ. Octree Representation Improves Data Fidelity of Cardiac CT Images and Convolutional Neural Network Semantic Segmentation of Left Atrial and Ventricular Chambers. Radiol Artif Intell 2021; 3:e210036. [PMID: 34870221 PMCID: PMC8637236 DOI: 10.1148/ryai.2021210036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 08/30/2021] [Accepted: 09/13/2021] [Indexed: 11/11/2022]
Abstract
PURPOSE To assess whether octree representation and octree-based convolutional neural networks (CNNs) improve segmentation accuracy of three-dimensional images. MATERIALS AND METHODS Cardiac CT angiographic examinations from 100 patients (mean age, 67 years ± 17 [standard deviation]; 60 men) performed between June 2012 and June 2018 with semantic segmentations of the left ventricular (LV) and left atrial (LA) blood pools at the end-diastolic and end-systolic cardiac phases were retrospectively evaluated. Image quality (root mean square error [RMSE]) and segmentation fidelity (global Dice and border Dice coefficients) metrics of the octree representation were compared with spatial downsampling for a range of memory footprints. Fivefold cross-validation was used to train an octree-based CNN and CNNs with spatial downsampling at four levels of image compression or spatial downsampling. The semantic segmentation performance of octree-based CNN (OctNet) was compared with the performance of U-Nets with spatial downsampling. RESULTS Octrees provided high image and segmentation fidelity (median RMSE, 1.34 HU; LV Dice coefficient, 0.970; LV border Dice coefficient, 0.843) with a reduced memory footprint (87.5% reduction). Spatial downsampling to the same memory footprint had lower data fidelity (median RMSE, 12.96 HU; LV Dice coefficient, 0.852; LV border Dice coefficient, 0.310). OctNet segmentation improved the border segmentation Dice coefficient (LV, 0.612; LA, 0.636) compared with the highest performance among U-Nets with spatial downsampling (Dice coefficients: LV, 0.579; LA, 0.592). CONCLUSION Octree-based representations can reduce the memory footprint and improve segmentation border accuracy.Keywords CT, Cardiac, Segmentation, Supervised Learning, Convolutional Neural Network (CNN), Deep Learning Algorithms, Machine Learning Algorithms© RSNA, 2021.
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Affiliation(s)
- Kunal Gupta
- From the Departments of Computer Science Engineering (K.G., N.S.),
Bioengineering (D.M.V., A.R.S., B.C., A.C., A.R., F.J.C.), and Radiology
(F.J.C.), University of California, San Diego, 9500 Gilman Dr, MC 0412, La
Jolla, CA 92093; and Department of Internal Medicine, Scripps Mercy Hospital,
San Diego, Calif (D.M.V.)
| | - Nitesh Sekhar
- From the Departments of Computer Science Engineering (K.G., N.S.),
Bioengineering (D.M.V., A.R.S., B.C., A.C., A.R., F.J.C.), and Radiology
(F.J.C.), University of California, San Diego, 9500 Gilman Dr, MC 0412, La
Jolla, CA 92093; and Department of Internal Medicine, Scripps Mercy Hospital,
San Diego, Calif (D.M.V.)
| | - Davis M. Vigneault
- From the Departments of Computer Science Engineering (K.G., N.S.),
Bioengineering (D.M.V., A.R.S., B.C., A.C., A.R., F.J.C.), and Radiology
(F.J.C.), University of California, San Diego, 9500 Gilman Dr, MC 0412, La
Jolla, CA 92093; and Department of Internal Medicine, Scripps Mercy Hospital,
San Diego, Calif (D.M.V.)
| | - Anderson R. Scott
- From the Departments of Computer Science Engineering (K.G., N.S.),
Bioengineering (D.M.V., A.R.S., B.C., A.C., A.R., F.J.C.), and Radiology
(F.J.C.), University of California, San Diego, 9500 Gilman Dr, MC 0412, La
Jolla, CA 92093; and Department of Internal Medicine, Scripps Mercy Hospital,
San Diego, Calif (D.M.V.)
| | - Brendan Colvert
- From the Departments of Computer Science Engineering (K.G., N.S.),
Bioengineering (D.M.V., A.R.S., B.C., A.C., A.R., F.J.C.), and Radiology
(F.J.C.), University of California, San Diego, 9500 Gilman Dr, MC 0412, La
Jolla, CA 92093; and Department of Internal Medicine, Scripps Mercy Hospital,
San Diego, Calif (D.M.V.)
| | - Amanda Craine
- From the Departments of Computer Science Engineering (K.G., N.S.),
Bioengineering (D.M.V., A.R.S., B.C., A.C., A.R., F.J.C.), and Radiology
(F.J.C.), University of California, San Diego, 9500 Gilman Dr, MC 0412, La
Jolla, CA 92093; and Department of Internal Medicine, Scripps Mercy Hospital,
San Diego, Calif (D.M.V.)
| | - Adhithi Raghavan
- From the Departments of Computer Science Engineering (K.G., N.S.),
Bioengineering (D.M.V., A.R.S., B.C., A.C., A.R., F.J.C.), and Radiology
(F.J.C.), University of California, San Diego, 9500 Gilman Dr, MC 0412, La
Jolla, CA 92093; and Department of Internal Medicine, Scripps Mercy Hospital,
San Diego, Calif (D.M.V.)
| | - Francisco J. Contijoch
- From the Departments of Computer Science Engineering (K.G., N.S.),
Bioengineering (D.M.V., A.R.S., B.C., A.C., A.R., F.J.C.), and Radiology
(F.J.C.), University of California, San Diego, 9500 Gilman Dr, MC 0412, La
Jolla, CA 92093; and Department of Internal Medicine, Scripps Mercy Hospital,
San Diego, Calif (D.M.V.)
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Chen Z, Rigolli M, Vigneault DM, Kligerman S, Hahn L, Narezkina A, Craine A, Lowe K, Contijoch F. Automated cardiac volume assessment and cardiac long- and short-axis imaging plane prediction from electrocardiogram-gated computed tomography volumes enabled by deep learning. EUROPEAN HEART JOURNAL. DIGITAL HEALTH 2021; 2:311-322. [PMID: 34223176 PMCID: PMC8242184 DOI: 10.1093/ehjdh/ztab033] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 03/01/2021] [Accepted: 03/19/2021] [Indexed: 01/29/2023]
Abstract
AIMS To develop an automated method for bloodpool segmentation and imaging plane re-slicing of cardiac computed tomography (CT) via deep learning (DL) for clinical use in coronary artery disease (CAD) wall motion assessment and reproducible longitudinal imaging. METHODS AND RESULTS One hundred patients who underwent clinically indicated cardiac CT scans with manually segmented left ventricle (LV) and left atrial (LA) chambers were used for training. For each patient, long-axis (LAX) and short-axis planes were manually defined by an imaging expert. A DL model was trained to predict bloodpool segmentations and imaging planes. Deep learning bloodpool segmentations showed close agreement with manual LV [median Dice: 0.91, Hausdorff distance (HD): 6.18 mm] and LA (Dice: 0.93, HD: 7.35 mm) segmentations and a strong correlation with manual ejection fraction (Pearson r: 0.95 LV, 0.92 LA). Predicted planes had low median location (6.96 mm) and angular orientation (7.96 ° ) errors which were comparable to inter-reader differences (P > 0.71). 84-97% of DL-prescribed LAX planes correctly intersected American Heart Association segments, which was comparable (P > 0.05) to manual slicing. In a test cohort of 144 patients, we evaluated the ability of the DL approach to provide diagnostic imaging planes. Visual scoring by two blinded experts determined ≥94% of DL-predicted planes to be diagnostically adequate. Further, DL-enabled visualization of LV wall motion abnormalities due to CAD and provided reproducible planes upon repeat imaging. CONCLUSION A volumetric, DL approach provides multiple chamber segmentations and can re-slice the imaging volume along standardized cardiac imaging planes for reproducible wall motion abnormality and functional assessment.
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Affiliation(s)
- Zhennong Chen
- Department of Bioengineering, UC San Diego School of Engineering, 9500 Gilman Drive, MC 0412, La Jolla, CA 92093, USA
| | - Marzia Rigolli
- Department of Bioengineering, UC San Diego School of Engineering, 9500 Gilman Drive, MC 0412, La Jolla, CA 92093, USA
| | - Davis Marc Vigneault
- Department of Internal Medicine, Scripps Mercy Hospital, 4077 Fifth Ave, San Diego, CA 92103, USA
| | - Seth Kligerman
- Department of Radiology, UC San Diego School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Lewis Hahn
- Department of Radiology, UC San Diego School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Anna Narezkina
- Department of Medicine, Division of Cardiology, UC San Diego School of Medicine, 9500 Gilman Dr, La Jolla, CA 92093, USA
| | - Amanda Craine
- Department of Bioengineering, UC San Diego School of Engineering, 9500 Gilman Drive, MC 0412, La Jolla, CA 92093, USA
| | - Katherine Lowe
- Department of Bioengineering, UC San Diego School of Engineering, 9500 Gilman Drive, MC 0412, La Jolla, CA 92093, USA
| | - Francisco Contijoch
- Department of Bioengineering, UC San Diego School of Engineering, 9500 Gilman Drive, MC 0412, La Jolla, CA 92093, USA
- Department of Radiology, UC San Diego School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093, USA
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11
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Manohar A, Colvert GM, Schluchter A, Contijoch F, McVeigh ER. Anthropomorphic left ventricular mesh phantom: a framework to investigate the accuracy of SQUEEZ using Coherent Point Drift for the detection of regional wall motion abnormalities. J Med Imaging (Bellingham) 2019; 6:045001. [PMID: 31824981 PMCID: PMC6903427 DOI: 10.1117/1.jmi.6.4.045001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 11/18/2019] [Indexed: 11/14/2022] Open
Abstract
We present an anthropomorphically accurate left ventricular (LV) phantom derived from human computed tomography (CT) data to serve as the ground truth for the optimization and the spatial resolution quantification of a CT-derived regional strain metric (SQUEEZ) for the detection of regional wall motion abnormalities. Displacements were applied to the mesh points of a clinically derived end-diastolic LV mesh to create analytical end-systolic poses with physiologically accurate endocardial strains. Normal function and regional dysfunction of four sizes [1, 2/3, 1/2, and 1/3 American Heart Association (AHA) segments as core diameter], each exhibiting hypokinesia (70% reduction in strain) and subtle hypokinesia (40% reduction in strain), were simulated. Regional shortening (RS CT ) estimates were obtained by registering the end-diastolic mesh to each simulated end-systolic mesh condition using a nonrigid registration algorithm. Ground-truth models of normal function and of hypokinesia were used to identify the optimal parameters in the registration algorithm and to measure the accuracy of detecting regional dysfunction of varying sizes and severities. For normal LV function,RS CT values in all 16 AHA segments were accurate to within ± 5 % . For cases with regional dysfunction, the errors inRS CT around the dysfunctional region increased with decreasing size of dysfunctional tissue.
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Affiliation(s)
- Ashish Manohar
- University of California San Diego, Department of Mechanical and Aerospace Engineering, La Jolla, California, United States
| | - Gabrielle M. Colvert
- University of California San Diego, Department of Bioengineering, La Jolla, California, United States
| | - Andrew Schluchter
- University of California San Diego, Department of Bioengineering, La Jolla, California, United States
| | - Francisco Contijoch
- University of California San Diego, Department of Bioengineering, La Jolla, California, United States
- University of California San Diego, Department of Radiology, La Jolla, California, United States
| | - Elliot R. McVeigh
- University of California San Diego, Department of Bioengineering, La Jolla, California, United States
- University of California San Diego, Department of Radiology, La Jolla, California, United States
- University of California San Diego, Cardiology Division, Department of Medicine, La Jolla, California, United States
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Kobayashi K, Wakasa S, Sato K, Kanai S, Date H, Kimura S, Oyama-Manabe N, Matsui Y. Quantitative analysis of regional endocardial geometry dynamics from 4D cardiac CT images: endocardial tracking based on the iterative closest point with an integrated scale estimation. ACTA ACUST UNITED AC 2019; 64:055009. [DOI: 10.1088/1361-6560/ab009a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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13
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Di Salvo G, Miller O, Babu Narayan S, Li W, Budts W, Valsangiacomo Buechel ER, Frigiola A, van den Bosch AE, Bonello B, Mertens L, Hussain T, Parish V, Habib G, Edvardsen T, Geva T, Baumgartner H, Gatzoulis MA, Delgado V, Haugaa KH, Lancellotti P, Flachskampf F, Cardim N, Gerber B, Masci PG, Donal E, Gimelli A, Muraru D, Cosyns B. Imaging the adult with congenital heart disease: a multimodality imaging approach—position paper from the EACVI. Eur Heart J Cardiovasc Imaging 2018; 19:1077-1098. [DOI: 10.1093/ehjci/jey102] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Accepted: 06/28/2018] [Indexed: 12/18/2022] Open
Affiliation(s)
- Giovanni Di Salvo
- Department of Adult Congenital Heart Disease, National Heart and Lung Institute, Imperial College London, Royal Brompton Hospital, Sydney Street, London, UK
| | - Owen Miller
- Department of Congenital Heart Disease, Evelina London Children's Hospital, Guy's and St. Thomas' NHS Foundation Trust, Westminster Bridge Road, London, UK
| | - Sonya Babu Narayan
- Department of Adult Congenital Heart Disease, National Heart and Lung Institute, Imperial College London, Royal Brompton Hospital, Sydney Street, London, UK
| | - Wei Li
- Department of Adult Congenital Heart Disease, National Heart and Lung Institute, Imperial College London, Royal Brompton Hospital, Sydney Street, London, UK
| | - Werner Budts
- Department Cardiovascular Sciences (KU Leuven), Congenital and Structural Cardiology (CSC UZ Leuven), Leuven, Belgium
| | | | - Alessandra Frigiola
- Adult Congenital Heart Disease, Guy's and St Thomas' Hospital, Westminster Bridge Road, London, UK
| | | | - Beatrice Bonello
- Department of Paediatric Cardiology, Great Ormond Street Hospital, London, UK
| | - Luc Mertens
- Division of Cardiology, Labatt Family Heart Centre, Hospital for Sick Children and University of Toronto, SickKids, 555 University Avenue Toronto, Ontario, Canada
| | - Tarique Hussain
- Division of Imaging Sciences and Biomedical Engineering, King's College London, London, UK
- Departments of Paediatrics, University of Texas, Southwestern Medical Center, Dallas, TX, USA
| | | | - Gilbert Habib
- APHM, La Timone Hospital, Cardiology Department, Boulevard Jean Moulin, Marseille, France
| | - Thor Edvardsen
- Department of Cardiology, Sognsvannsveien 20, Oslo, Norvegia
| | - Tal Geva
- Department of Cardiology, 300 Longwood Avenue, Farley, Boston, Massachusetts, USA
| | | | - Michael A Gatzoulis
- Department of Adult Congenital Heart Disease, National Heart and Lung Institute, Imperial College London, Royal Brompton Hospital, Sydney Street, London, UK
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14
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Regional myocardial strain measurements from 4DCT in patients with normal LV function. J Cardiovasc Comput Tomogr 2018; 12:372-378. [PMID: 29784623 DOI: 10.1016/j.jcct.2018.05.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 02/09/2018] [Accepted: 05/03/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND CT SQUEEZ is a new automated technique to evaluate regional endocardial strain by tracking features on the endocardium from 4D cine CT data. The objective of this study was to measure the range of endocardial regional strain (RSCT) values obtained with CT SQUEEZ in the normal human left ventricle (LV) from standard clinical 4D coronary CTA exams. METHODS RSCT was measured over the heart cycle in 25 humans with normal LV function using cine CT from three vendors. Mean and standard deviation of RSCT values were computed in 16 AHA LV segments to estimate the range of values expected in the normal LV. RESULTS Curves describing RSCT vs. time were consistent between subjects. There was a slight gradient of decreasing minimum RSCT value (increased shortening) from the base to the apex of the heart. Mean RSCT values at end-systole were: base = -32% ± 1%, mid = -33% ± 1%, apex = -36% ± 1%. The standard deviation of the minimum systolic RSCT in each segment over all subjects was 5%. The average time to reach maximum shortening was 34% of the RR interval. CONCLUSIONS Regional strain (RSCT) can be rapidly obtained from standard gated coronary CCTA protocols using 4DCT SQUEEZ processing. We estimate that 95% of normal LV end-systolic RSCT values will fall between -23% and -43%; therefore, we hypothesize that an RSCT value higher than -23% will indicate a hypokinetic segment in the human heart.
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15
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Andreini D, Conte E, Mushtaq S. Cardiac-CT in 2017: Over the coronary artery assessment. Int J Cardiol 2017; 249:497-499. [PMID: 28970038 DOI: 10.1016/j.ijcard.2017.09.177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 09/14/2017] [Indexed: 11/24/2022]
Affiliation(s)
- Daniele Andreini
- Centro Cardiologico Monzino, IRCCS, Milan, Italy; Department of Clinical Sciences and Community Health, Cardiovascular Section, University of Milan, Milan, Italy.
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