Detection Of Wall Motion Abnormalities Research Articles

Abstract 17934: Performance of an Electrocardiographic Deep Learning Model for Detecting Wall Motion Abnormalities: An Analysis of Impact From Cardiovascular Comorbidities and Race in an External Validation Study

Introduction: Cardiac wall motion abnormalities (WMA) are key prognostic indicators for major cardiovascular events and mortality (MACE), yet poorly detected by current ECG screening such as for Q waves. Given that race and gender impact the ECG, it is also unknown if ECG screening for WMA could be applied broadly. We hypothesized that deep learning of the ECG could accurately identify WMA in diverse patients with varying comorbidities at 2 Institutions. Methods: We developed a DL Convolutional Neural Network model on N=35,210 ECG records from Stanford University (iECG, Philips), labeled by natural language processing of echocardiography reports within 60 days ( Panel A ). The tested model was then externally validated on an independent set of N=2338 ECGs from Emory University (Muse, GE). Patients with ventricular pacing were excluded. The patient cohort was segmented by cardiovascular comorbidity (<3, >=3) and white vs. non-white race to compare model performance. Results: The Stanford cohort (62.9±16.9 years, 47% female, 58% white, 6% black, 16% Asian, 23% >=3 comorbidities) differed from the Emory cohort (61.9±16.0 years, 48% female, 48% white, 41% black, 6% Asian, 52% >=3 comorbidities). Nevertheless, the Stanford model detected WMA in the Emory cohort with AUC 0.723. For patients with low and high comorbidity burdens, the AUC was 0.71 and 0.69, respectively. For White and Non-White patients, the AUC was 0.74/0.70 and 0.65/0.66, respectively ( Panel B ). Conclusions: Across racial groups and patients with variable burden of comorbidities, a DL model of electrocardiograms robustly identifies WMAs in an external validation cohort despite differences in the populations. The model’s performance across different comorbidity and racial demographic groups underscores its potential for general clinical application, offering an effective tool for clinical screening and enhanced risk stratification.

Abstract 13615: Diagnostic Accuracy of Cardiac MRI for Detecting Wall Motion Abnormalities and Coronary Artery Stenosis - A Systematic Review and Umbrella Meta-Analysis

Introduction: Conventional coronary angiography (CCA) is the gold standard for the diagnosis of coronary artery disease (CAD). It is an invasive test and carries risks. Increased mortality is linked with reduced coronary flow, thus aggressively measuring coronary flow is important. Cardiac MRI (cMRI) is an emerging non-invasive test that can also help in assessing ventricular function, myocardial perfusion, and detecting anomalies. Aim: We aimed to analyze the diagnostic accuracy of cMRI compared to CCA through an umbrella meta-analysis. Methods: We searched PubMed articles comparing the diagnostic accuracy of cMRI with CCA in patients having CAD published from 2000 to 2022 according to PRISMA guidelines. We used the generic inverse variance method to pool sensitivity (SN), specificity (SP), negative likelihood ratio, positive likelihood ratio, and diagnostic odds ratio (DOR) with 95% confidence interval keeping alpha criteria of 0.05 as significant. RevMan 5.4 was used to calculate random effects models. Results: In this umbrella meta-analysis, 9 studies with 14615 patients met inclusion criteria. Overall pooled SN was 0.88 (95% CI: 0.87-0.90), SP was 0.85 (0.81-0.89), PLR was 6.07 (5.02-7.33), NLR was -1.99 (-2.10 to -1.87), and DOR 38.94 (31.96-47.46). (p<0.00001) Conclusion: The diagnostic accuracy of a non-invasive, cMRI is comparable, if not superior to an invasive test like CCA.

FOCUS may detect wall motion abnormalities in patients with ACS

BackgroundChest pain is a common presentation to the Emergency Department (ED) with roughly 6 million visits a year. The primary diagnostic modality for the identification of acute coronary syndrome (ACS) is the electrocardiogram (ECG), which is used to screen for electrocardiographic findings representing acute coronary occlusion. It is known that the ischemia generated by an acutely occluded coronary vessel generates a wall motion abnormality which can be visualized by echocardiogram; however, emergency physician-performed focused cardiac ultrasound (FOCUS) currently does not have a formal role in the diagnosis of OMI within the emergency department. PurposeWe sought to define the characteristics of FOCUS performed by emergency physicians of variable training levels in the identification of RWMA in patients presenting to the emergency department with high suspicion for ACS before undergoing cardiac catheterization or formal echocardiography. We also explored whether RWMA was associated with OMI in these patients. MethodsWe performed a structured, retrospective review of adult patients presenting to a large, academic, tertiary care center with suspected ACS from July 1st, 2019, and October 24th, 2020. Patients were included if they underwent FOCUS in the ED during the time-period above for suspected ACS looking for RWMA and FOCUS images were stored and reviewable in our middleware software. The primary outcome was the accuracy, sensitivity, and specificity of FOCUS compared to formal echocardiography for the detection of RWMA. Secondary outcomes were sensitivity of FOCUS compared to formal echocardiography for detection of RWMA in patients with and without cardiac catheterization proven OMI and sensitivity and specificity of FOCUS operators based on training. ResultsFOCUS for RWMA performed by emergency physicians had a sensitivity of 94% (95% CI, 82–98), specificity 35% (95% CI, 15–61), and overall accuracy of 78% (95% CI, 66–87). Of all subjects, 82% underwent urgent or emergency coronary angiography, of which 71% had OMI at the time of coronary angiography of the procedure. FOCUS identified RWMA in 87% of patients with coronary angiography proven OMI. Residents (PGY-1 - PGY-3) (n = 31) were able to detect RWMA with a sensitivity of 86% (95% CI, 64–96), a specificity of 56% (95% CI, 23–85%), and an accuracy of 77 (95% CI, 58–90%). Emergency ultrasound fellows and attendings (n = 34) were able to detect RWMA with a sensitivity of 85% (95% CI, 64–95%), a specificity of 75% (95% CI, 36–96%), and an accuracy of 82% (95% CI, 65–93%). ConclusionsOur retrospective study concludes FOCUS performed by emergency physicians may be used to detect RWMA in patients with high concern for acute coronary syndrome. This may have its greatest utility in patients presenting without STEMI where the ECG is felt to be equivocal, but the clinician has high concern for OMI, in which the presence of RWMA might result in emergent cath lab activation, though this requires further study. The presence of RWMA in such cases may help to rule in OMI as a cause; however, the absence of RWMA should exclude OMI. Further research is necessary to confirm these findings.

Deep learning automates detection of wall motion abnormalities via measurement of longitudinal strain from ECG-gated CT images.

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). 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. 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). 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.

Value of 3D echocardiography in the diagnosis of arrhythmogenic right ventricular cardiomyopathy.

The 2010 Task Force Criteria (TFC) require that both right ventricular (RV) regional wall-motion abnormalities (WMA) and specific RV size cut-offs be met in order to fulfil one of the major criterion for arrhythmogenic right ventricular cardiomyopathy (ARVC) diagnosis. Currently, 2D echocardiography (2DE) and cardiovascular magnetic resonance imaging (cMRI) are used to determine if these criteria are met. Little is known about the diagnostic value of 3D echocardiography (3DE) in ARVC. The aim of this study was to determine whether a combination of 2DE-3DE is non-inferior to the currently used 2DE-cMRI combination in the diagnosis of patients with ARVC. Thirty-nine individuals (47±15 years) with suspected ARVC underwent evaluation of the RV with cMRI, 2DE, and 3DE. 3DE and cMRI were independently used to obtain RV volumes, ejection fraction (EF) and determine the presence of segmental RV WMA. Studies were blindly classified as meeting criteria for ARVC in accordance with the 2010 TFC. Kappa statistics were used to test the concordance between 2DE-cMRI and 2DE-3DE approaches. Using the 2DE-cMRI approach, 3/39 were not affected, 5/39 possible, 8/39 borderline, and 23/39 definite ARVC. The proposed 2DE-3DE approach yielded 5/39 not affected, 7/39 possible, 8/39 borderline, and 19/39 definite diagnoses. The two approaches were highly concordant (k = 0.71; 95% confidence interval: 0.44-0.84). Although 3DE underestimated RV volumes in comparison with cMRI, interfering, in some instances with the fulfilment of a major criterion, it was able to identify more RV WMA (28/39) than 2DE (11/39), with a detection-rate comparable to cMRI (33/39) highlighting a unique advantage. The combination of 2DE-3DE for ARVC diagnosis is comparable to the conventional 2DE-cMRI approach. 3DE should be performed in all suspected ARVC patients to aide in the detection of WMA.

440 Deep Learning Enables Automated Evaluation Of Global Longitudinal Shortening From Cine CT

Introduction: CineCT is increasingly being used to evaluate cardiac dynamics. However, current evaluation typically depends on visual assessment, 3D segmentation, or evaluation based on wall thickening. Echocardiography and CMR have demonstrated the utility of global longitudinal shortening (GLS). Currently measuring GLS with CT 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 deep learning framework to automatically and accurately measure GLS for detection of wall motion abnormalities (WMA).

Utility of Handheld Ultrasound Performed by Cardiology Fellows in Patients Presenting with Suspected ST-Elevation Myocardial Infarction.

In academic hospitals, cardiology fellows may be the first point of contact for patients presenting with suspected ST-elevation myocardial infarction (STEMI) or acute coronary syndrome (ACS). In this study, we sought to determine the role of handheld ultrasound (HHU) in patients with suspected acute myocardial injury (AMI) when used by fellows in training, its association with the year of training in cardiology fellowship, and its influence on clinical care. This prospective study's sample population comprised patients who presented to the Loma Linda University Medical Center Emergency Department with suspected acute STEMI. On-call cardiology fellows performed bedside cardiac HHU at the time of AMI activation. All patients subsequently underwent standard transthoracic echocardiography (TTE). The impact of the detection of wall motion abnormalities (WMAs) on HHU in regard to clinical decision-making, including whether the patient would undergo urgent invasive angiography, was also evaluated. Eighty-two patients (mean age: 65 years, 70% male) were included. The use of HHU by cardiology fellows resulted in a concordance correlation coefficient of 0.71 (95% confidence interval: 0.58-0.81) between HHU and TTE for left ventricular ejection fraction (LVEF), and a concordance correlation coefficient of 0.76 (0.65-0.84) for wall motion score index. Patients with WMA on HHU were more likely to undergo invasive angiogram during hospitalization (96% vs. 75%, P < 0.01). The time interval between the performance of HHU to initiation of cardiac catheterization (time-to-cath) was shorter in patients with abnormal versus normal HHU examinations (58 ± 32 min vs. 218 ± 388 min, P = 0.06). Finally, among patients who underwent angiography, those with WMA were more likely to undergo angiography within 90 min of presentation (96% vs. 66%, P < 0.001). HHU can be reliably used by cardiology fellows in training for measurement of LVEF and assessment of wall motion abnormalities, with good correlation to findings obtained via standard TTE. HHU-identified WMA at first contact was associated with higher rates of angiography as well as sooner angiography compared to patients without WMA.

Оцінка повздовжньої деформації лівого шлуночка і її зміни при інфаркті міокарда та ішемічній хворобі серця з обструктивним ураженням коронарних артерій

The review provides data on a new method of ultrasound diagnostics – speckle tracking echocardiography in the diagnosis of myocardial infarction and coronary heart disease with obstructive coronary artery lesions, the advantages of the global longitudinal strain (GLS) compared to the existing echocardiographic indicators of global systolic and segmental systolic function. The value of measuring GLS in coronary heart disease is the quantitative detection of wall motion abnormalities, when left ventricular ejection fraction is within normal values and visual assessment does not detect violations of regional contractility. In patients with myocardial infarction without ST-segment elevation, GLS measurement may assist in the selection of patients who need urgent reperfusion therapy. In coronary heart disease, GLS can complement the conventional assessment of wall movement; replace the need for additional non-invasive testing for some patients with suboptimal stress tests. The normal limits of the GLS for various manufacturers of ultrasound scanners and technical characteristics for the correct studying of the GLS are described. The value of the GLS gradually decreases in mild, moderate and severe forms of coronary heart disease, and is the lowest in patients with myocardial infarction with ST segment elevation. The possibilities of detecting infarct-related coronary artery using the amplitude of the segmental strain and the «bull’s eye» diagram in isolated lesions of one of the coronary arteries are described. The analysis of the strain curves is carried out, the characteristics of the strain curve in normal conditions and in ischemia are presented. The probable signs of ischemia are the phenomena of early systolic lengthening and postsystolic shortening on the curves of longitudinal deformation. The conditions when the postsystolic contraction on the strain curve is pathological are described. Key words: global longitudinal strain, myocardial infarction, ischemic heart disease, «bull’s eye», early systolic lengthening, postsystolic shortening.

B-PO01-081 MACHINE LEARNING OF THE ELECTROCARDIOGRAM IDENTIFIES CARDIAC WALL MOTION ABNORMALITIES BEYOND THE Q WAVE

Ventricular wall motion abnormalities (WMA) and desynchrony strongly predict sudden arrhythmic and cardiac death. Q-waves on the 12 lead ECG can aide localization and detection of WMA, but have modest predictive accuracy. We hypothesized that deep learning of the ECG can better identify WMA. To develop a deep convolutional network using the ECG to accurately predict the presence of WMA on the echocardiogram gold standard. We collected ECGs in 36,964 unique patients with echocardiography within 60 days. We identified WMA using a novel scalable approach of natural language processing (NLP) of clinical reports. We developed a convolutional neural network (CNN) matching input ECG digital waveforms to outputs of WMA on NLP-processed echo reports (Fig A). We used 70%, 10%, and 20% for training, validation, and testing cohorts, respectively. We then probed CNN to identify ECG regions that most contributed to identifying WMA. CNN of the ECG detected echocardiographic WMA with a C-statistic of 0.822 (CI 0.806 - 0.837). Conversely, Q waves provided c-statistic of 0.599 (CI: 0.577-0.621; p<0.0001; Fig B). CNN accuracy did not improve with inclusion of demographic data. We probed CNN and found that ECG regions outside the Q-wave, throughout the QRS and T wave (Fig C) were used to identify WMA. Deep learning of the ECG outperforms traditional Q-wave analysis to detect WMA on echocardiography. These data suggest novel digital ECG signatures of normal and abnormal contraction. Further studies could be directed to reveal regional desynchrony or response to resynchronization therapy.

P365 Echocardiographic deformation imaging improves detection of arrhythmogenic right ventricular cardiomyopathy; a head-to-head comparison of deformation imaging and conventional assessment

Abstract Background Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is an inherited cardiomyopathy diagnosed by a complex set of tests defined in the 2010 Task Force Criteria (TFC). For echocardiography, right ventricular (RV) dilatation and function are combined with visual wall motion assessment to obtain diagnostic criteria. However, subtle wall motion abnormalities can be missed by visual assessment, thereby limiting detection of disease. Recent studies have shown that echocardiographic deformation imaging has high sensitivity for detection of wall motion abnormalities. However, the performance of deformation imaging within the 2010 TFC for ARVC diagnosis remains unknown. Objectives To perform a head-to-head comparison of the diagnostic value of visual wall motion assessment versus deformation imaging in a real-world cohort of consecutive patients evaluated for ARVC. Methods We included a consecutive cohort of 163 patients who were referred for ARVC evaluation between 2009-2011, of whom 59 patients underwent an echocardiogram with images available for deformation analysis. Patients were diagnosed by consensus of 3 independent ARVC experts with access to all patient data including a median follow-up of 5.9 years IQR[2.7-7.6 yrs]. The original clinical assessment of RV outflow tract (RVOT) dimensions, fractional area change and wall motion was used. In addition, deformation patterns of the subtricuspid area were scored as normal (type I) or abnormal (type II/III), according to the presence of regional mechanical dysfunction (see figure). We evaluated the effect of replacing visual wall motion assessment with deformation imaging on the sensitivity, specificity and balanced accuracy of the echocardiographic TFC. Results Of 59 patients (age 38 ± 17 yrs, 49% male), the expert panel diagnosed 15 (25%) with ARVC. Conventional TFC, either minor or major, were observed in 10 patients; replacing visual wall motion assessment with deformation imaging led to 5 additional detections of ARVC patients, whereas 0 were lost. Consequently, deformation imaging increased sensitivity from 67% to 100%, whereas specificity decreased from 89% to 73%. The balanced accuracy increased from 0.78 to 0.86. Of the 12 patients with false positive TFC by deformation imaging, half were asymptomatic mutation carriers at risk for developing ARVC. Of the other 6 false positives, 3 were diagnosed with ventricular arrhythmia from the RVOT. There were no false negative diagnoses using deformation imaging. Conclusion All definite ARVC patients were detected when deformation imaging patterns were used to evaluate wall motion abnormalities. This increased sensitivity was accompanied by a slight decrease in specificity. Deformation imaging on its own was not able to reliably distinguish ARVC from other RV related disease. Since no ARVC diagnoses were missed, echocardiographic deformation imaging could be of great value to exclude ARVC in patients referred for ARVC evaluation. Abstract P365 Figure. Deformation patterns and % TFC per group

The role of stress echocardiography in cardiovascular disorders.

Stress echocardiography is a safe, low‑cost, widely available, radiation‑free versatile imaging modality that is becoming increasingly recognized as a valuable tool in the assessment of coronary heart disease. In recent years, there has also been an increasing use of stress echocardiography in the assessment of nonischemic cardiac disease given its unique ability for simultaneous assessment of both functional performance and exercise‑related noninvasive hemodynamic changes, which can help guide treatment and inform about the prognosis of the patients. Today, in the echocardiography laboratory, we can not only detect wall motion abnormalities resulting from coronary artery stenosis, but also detect alterations to the coronary microvessels, left ventricular systolic and diastolic parameters, heart valves, pulmonary circulation, alveolar‑capillary barrier, and right ventricle. The role of stress echo has been well established in several pathologies, such as aortic stenosis and hypertrophic cardiomyopathy; however, other indications, namely the results of diastolic stress testing and pulmonary hypertension, need additional data and research. This paper presents the current evidence for the role of stress testing in mitral regurgitation, aortic stenosis, hypertrophic cardiomyopathy, heart failure with preserved ejection fraction, and pulmonary hypertension.

Improving Visual Detection of Wall Motion Abnormality with Echocardiographic Image Enhancing Methods.

Analysis of wall motion abnormality using echocardiography is an established method for detecting myocardial ischemia. We describe a hybrid approach of enhancing 2D+T echo datasets with border detection and Eulerian motion magnification to improve the visual assessment of wall motion. We implemented a local phase-based approach using the monogenic signal and its derived features, either feature asymmetry (FA) or oriented feature symmetry (OFS), to detect boundaries of the heart structure. We enhanced the 2D+T datasets using either an intensity-based or phase-based Eulerian Motion Magnification (EMM) video processing technique, and identified among eight different types of enhancements the best performing method as OFS with an accuracy of 78% versus the original B-Mode with an accuracy of 71%.

Noninvasive evaluation of global and regional left ventricular function using computed tomography and magnetic resonance imaging: a meta-analysis.

To compare the diagnostic accuracy of computed tomography (CT) in the assessment of global and regional left ventricular (LV) function with magnetic resonance imaging (MRI). MEDLINE, EMBASE and ISI Web of Science were systematically reviewed. Evaluation included: ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and left ventricular mass (LVM). Differences between modalities were analysed using limits of agreement (LoA). Publication bias was measured by Egger's regression test. Heterogeneity was evaluated using Cochran's Q test and Higgins I2 statistic. In the presence of heterogeneity the DerSimonian-Laird method was used for estimation of heterogeneity variance. Fifty-three studies including 1,814 patients were identified. The mean difference between CT and MRI was -0.56 % (LoA, -11.6-10.5 %) for EF, 2.62 ml (-34.1-39.3 ml) for EDV and 1.61 ml (-22.4-25.7 ml) for ESV, 3.21 ml (-21.8-28.3 ml) for SV and 0.13 g (-28.2-28.4 g) for LVM. CT detected wall motion abnormalities on a per-segment basis with 90 % sensitivity and 97 % specificity. CT is accurate for assessing global LV function parameters but the limits of agreement versus MRI are moderately wide, while wall motion deficits are detected with high accuracy. • CT helps to assess patients with coronary artery disease (CAD). • MRI is the reference standard for evaluation of left ventricular function. • CT provides accurate assessment of global left ventricular function.

Left Main Dissection and Pseudoaneurysm Formation After a Road Traffic Accident

We present here the case of a 46-year-old man, a smoker, who was involved in a motor vehicle accident. He was hit by a car while driving his motorcycle. The emergency medical care team found that the patient had a Glasgow Coma Scale score of 3 and quickly developed a bradyasystolic cardiac arrest. After successful advanced resuscitation, the ECG showed right bundle-branch block and anterolateral ST-segment elevation (Figure 1), so the patient was transported to the intensive care unit. Figure 1. ECG after the cardiac arrest showing right bundle-branch block and anterolateral ST-segment elevation. First, a body computed tomography scan and x-ray were done, demonstrating jaw, rib, femur, and tibia fractures without any points of active bleeding. The right bundle-branch block disappeared but the ST-segment elevation persisted on ECG. In addition, an urgent echocardiogram detected wall motion abnormalities with an anteroseptal akinetic area and a moderately depressed ejection fraction without pericardial effusion (Movies I and II in the online-only Data Supplement). Consequently, an emergency coronary angiogram showed a thin radiolucent line in the distal left main coronary artery (LMCA) that suggested intimal flap (dissection) with Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow in the left anterior descending (LAD) artery and left circumflex artery (Figure 2A …

Two-dimentional speckle tracking strain imaging in the assessment of myocardial diastolic function in patients with stable angina pectoris

Article type Systematic review article Introduction: Ischemic heart disease is caused mainly by obstruction of coronary arteries. The ischemic assessment through echocardiography is dependent on wall motion abnormality detection during systole. In patients with ischemic heart disease the diastolic function is impaired before systolic function and measurement of regional diastolic dysfunction if possible will be most sensitive for assessment of obstructed coronary artery region. This study was designed to determine whether regional left ventricular delayed relaxation diagnosis could be detected with strain imaging derived from two-dimensional speckle tracking echocardiography in patients with coronary artery disease. Methods: All the articles reviewed were obtained using MEDLINE & ScienceDirect (up to October 2014). All data extracted by speckle tracking echocardiography. The index which is used is strain imaging diastolic index which is calculated as: (A-B) A×100. A is the amount of strain at the time Aortic value closure and B is the amount of strain in first one-third point of diastolic duration. Result: Four articles were reviewed. Three articles assessed patients with echocardiography at rest and one with stress echocardiography. All articles showed the coronary artery tracking with significant stenosis is possible by regional deformation analysis through two-dimensional strain. Discussion: The usage of strain images obtained through two-dimensional speckle tracking has been validated for the quantitation assessment of regional dysfunction in ischemic heart disease. Regional LV delayed relaxation diagnosis with strain imaging is a reliable method after treadmill stress test. Conclusion: Strain imaging is reasonable for evaluation of ischemia as a low cost noninvasive test with high accuracy.

Three-dimensional cardiac cine imaging using the kat ARC acceleration: Initial experience in clinical adult patients at 3 T

ObjectiveThree-dimensional cardiac cine imaging has demonstrated promising clinical 1.5-Tesla results; however, its application to 3T scanners has been limited because of the higher sensitivity to off-resonance artifacts. The aim of this study was to apply 3D cardiac cine imaging during a single breath hold in clinical patients on a 3T scanner using the kat ARC (k- and adaptive-t auto-calibrating reconstruction for Cartesian sampling) technique and to evaluate the interchangeability between 2D and 3D cine imaging for cardiac functional analysis and detection of abnormalities in regional wall motion. MethodsFollowing institutional review board approval, we obtained 2D cine images with an acceleration factor of two during multiple breath holds and 3D cine images with a net scan acceleration factor of 7.7 during a single breath hold in 20 patients using a 3T unit. Two readers independently evaluated the wall motion of the left ventricle (LV) using a 5-point scale, and the consistency in the detection of regional wall motion abnormality between 2D and 3D cine was analyzed by Cohen's kappa test. The LV volume was calculated at end-diastole and end-systole (LVEDV, LVESV); the ejection fraction (LVEF) and myocardial weight (LVmass) were also calculated. The relationship between functional parameters calculated for 2D and 3D cine images was analyzed using Pearson's correlation analysis. The bias and 95% limit of agreement (LA) were calculated using Bland–Altman plots. In addition, a qualitative evaluation of image quality was performed with regard to the myocardium–blood contrast, noise level and boundary definition. ResultsDespite slight degradation in image quality for 3D cine, excellent agreement was obtained for the detection of wall motion abnormalities between 2D and 3D cine images (κ=0.84 and 0.94 for each reader). Excellent correlations between the two imaging methods were shown for the evaluation of functional parameters (r>0.97). Slight differences in LVEDV, LVESV, LVEF and LVmass were observed, with average values of 1.6±8.9mL, −0.6±5.9mL, 1.4±3.6%, and 1.3±8.7g, respectively. ConclusionsImages obtained using the kat ARC 3D and conventional 2D cine techniques were equivalent in the detection of regional wall motion abnormalities and the evaluation of cardiac functional parameters.

Masked Ischemia on Myocardial Perfusion Imaging: A Case Example

Introduction: Electrocardiography (ECG)-gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) for the diagnosis and prognosis of coronary artery disease (CAD) is the most commonly performed imaging procedure in nuclear cardiology. Case Presentation: A 67-year-old man underwent exercise electrocardiography (ECG)-gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) for evaluating his mild dyspnea on exertion (New York Heart Association class I). Images showed inducible ischemia of severe intensity in the interior walls and moderate intensity in the apicoseptal and anteroseptal segments, but exercise stress to induce coronary hyperemia revealed marked ST-segment depressions in low heart rates and the patient complained of only mild dyspnea during these ECG changes. He subsequently underwent coronary angiography, which revealed left main and severe three-vessel disease. This discrepancy between the SPECT perfusion images and the extent of coronary artery disease in this case represents the masking of one ischemic territory (left system) by another more severely ischemic territory (right system). Discussion: The reason is that we assess the relative and not absolute differences of the tracer uptake in this imaging modality. There may be other findings on MPI images which could help us overcome this pitfall, including detecting wall motion abnormalities, lung uptake of the tracer, or transient ischemic dilation. Another important issue is the ECG changes during exercise stress testing, which could point to a more extensive coronary artery disease than the one detected on MPI images alone.

Myocardial Perfusion, Scarring, and Function in Anomalous Left Coronary Artery From the Pulmonary Artery Syndrome: A Long-Term Analysis Using Magnetic Resonance Imaging

Anomalous left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital heart defect. We aimed to examine the role of cardiac magnetic resonance imaging (MRI) in the long-term surveillance ofrepaired ALCAPA with regard to myocardial scarring, wall motion abnormalities, perfusion deficits, and myocardial function. Twenty-one patients after direct reimplantation of ALCAPA (median age at operation, 2.8 years) wereexamined after a median 10.6 years by MRI at restandunder dobutamine stress conditions, echocardiography, and ergometry. Results were compared with preoperative, immediately postoperative (5 days), and intermediate-term (5.8 years) echocardiography. No early or late deaths occurred. Improvements in indexed left ventricular end-diastolic dimension, ejection fraction, and mitral valve function were observed in all patients. However, MRI at rest showed wall motion abnormalities in 67% and perfusion deficits in 28%. Myocardial scars were seen in 67%. Dobutamine stress MRI detected wall motion abnormalities in 19% and perfusion deficits in 14%, which were not seen on MRI at rest. Exercise testing did not reflect cardiac dysfunction. Although long-term follow-up showed global left ventricular function had improved after ALCAPA repair, MRI showed left ventricular wall motion abnormalities, perfusion deficits, and myocardial scarring were seen in many patients. Dobutamine stress MRI identified deficits that were not evident on MRI at rest, and can therefore be considered a valuable surveillance tool. These results suggest the need for lifelong surveillance of repaired ALCAPA.

Accuracy of ECG in assessment of postmyocardial infarction left ventricular function &amp; its comparison with echocardiography

[4] However, its usage in measuring the size of the infarct and assessing left ventricular function is a relatively new concept. The two dimensional echocardiography made it possible to detect wall motion abnormalities which are used to differentiate reliably between patient with myocardial ischaemia or early infarction and patient with nonischaemic chest pain. [5] The major advantages of the two dimensional echocardiography is its non-invasive use and repeatability of the examination. [6] The wall motion abnormalities detected using the echocardiography can be used safely in the diagnosis of myocardial infarction in the appropriate setting when electrocardiogram is non diagnostic. This technique has shown good correlation with functional infarct size with studies using thallium ventriculography, coronary angiography, peak creatinine phosphokinase levels and nuclear ventriculography. [3] 2D-Echocardiography, because of its ability to determine global and regional ventricular function is suited ideally for determining early and late prognosis in patients with acute myocardial infarction. [5] When performed early in the course of myocardial infarction 2D-echocardiography can help stratify high and low risk groups. Now a days measurement of left ventricular function is made by means of „Ejection Fraction‟. Ejection fraction is global index of extent of ventricular fiber shortening and provides useful measure of overall left ventricular pump function. ECG and 2-D echocardiography both are feasible and acceptable investigation to diagnose LV dysfunction. The outcome may be improved when the results of the two are compared for final evaluation. II. Material And Methods The present study was carried out in fifty cases of acute myocardial infarction patients in the tertiary care Hospital . All the patients who were admitted in the Medical wards who had demonstrated Q waves in their electrocardiogram were included in this study and screened.This also included patients shifted from coronary care units convalescing from acute infarct. Patients who had a history of DIABETES MELLITUS HYPERTENSION, CHRONIC RENAL FAILURE and/or on treatment for the same were excluded from the study as these diseases may affect the myocardium directly. Patients with non- Q wave infarcts, [7] Patient with conduction blocks assessed by electrocardiogram and Patients who showed electrocardiography evidence of Right or Left Ventricular hypertrophy by ESTES criteria were excluded. [8] Also,patients who had echocardiography evidence of valvular heart diseases of any of the four valves were excluded.

Value of strain analysis with feature tracking in dobutamine stress cardiac magnetic resonance imaging for detecting coronary artery disease

Background Dobutamine stress magnetic resonance (DSMR) has been established for the detection of coronary artery disease (CAD) due to its high diagnostic accuracy and prognostic value. The novel technique feature tracking (FT) analyses regional myocardial strain and thereby offers detailed information about myocardial deformation. The purpose of this study was to examine how FT based circumferential strain (CS) compares to visually detected wall motion abnormalities (WMA) during DSMR and whether it adds beneficial information for detecting CAD. Methods A total of 25 patients (72% male; mean age 64 ± 8) with suspected or known CAD underwent a standardized high-dose DSMR protocol at 1.5 T. CMR images were acquired at rest and during stress in three short-axis views (SAX; apical, medial, basal). None of the patients had evidence for WMAs or impaired left ventricular function at rest or scar tissue based on late gadolinium enhancement (LGE). For strain analysis the SAX planes were divided into 16 segments (n = 400 segments). All patients underwent x-ray coronary angiography for clinical reasons. Patients without WMA during DSMR and exclusion of CAD by coronary angiography were defined as normal and served as control (10 patients, 160 segments). 15 patients developed WMA during DSMR (34 segments). Additionally, based on angiographic findings, segments that were supplied by a vessel with >75% were defined as stenotic (64 segments). The remaining segments, which did not develop a WMA or were supplied by a vessel <50% narrowing, were considered as remote segments (161 segments). Results At rest no differences in CS were observed between groups (normal: -28.1 ± 8.9; WMA: -24.8 ± 12.9; stenotic: 25.8 ± 10.6; remote: 27.7 ± 11.7%; p = 0.23). High dose dobutamine stress revealed highly significant differences between normal segments and segments with WMA (normal: -39.3 ± 11.3%; WMA: 19.2 ± 19.1%; p < 0.001) as well as between normal and stenotic and normal and remote segments (stenotic: -23.8 ± 15.9%, p < 0.001; remote: -34.2 ± 14.1%, p < 0.001). Additionally, analysis of the absolute change in CS between rest and stress showed significant differences for normal segments vs. segments with WMA (Δ normal: -11.2 ± 12.6%, Δ WMA: 5.6 ± 22.9%; p = 0.001), as well as between normal and stenotic segments (Δ stenotic: 1.9 ± 18.4%; p < 0.001) and between normal and remote segments (Δ remote: -6.6 ± 16.3%; p = 0.027). CS results are summarized in Figure 1. ROC analysis of CS during maximum DSMR differentiated normal from stenotic segments with a sensitivity of 75% and specificity of 67% using a cutoff -33.2% with an area under the curve of 0.78 (Figure 2). Conclusions FT based CS analysis demonstrated significant differences between normal segments and segments with WMA in DSMR. Additionally, FT detected significantly impaired CS in stenotic segments compared to normal segments. FT based CS may improve the diagnostic accuracy of DSMR for detection of ischemia.