Myocardial Late Gadolinium Enhancement Research Articles

The Feasibility of a Model-Based Iterative Reconstruction Technique Tuned for the Myocardium on Myocardial Computed Tomography Late Enhancement.

This study evaluated the feasibility of a model-based iterative reconstruction technique (MBIR) tuned for the myocardium on myocardial computed tomography late enhancement (CT-LE). Twenty-eight patients who underwent myocardial CT-LE and late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) within 1 year were retrospectively enrolled. Myocardial CT-LE was performed using a 320-row CT with low tube voltage (80 kVp). Myocardial CT-LE images were scanned 7 min after CT angiography (CTA) without additional contrast medium. All myocardial CT-LE images were reconstructed with hybrid iterative reconstruction (HIR), conventional MBIR (MBIR_cardiac), and new MBIR tuned for the myocardium (MBIR_myo). Qualitative (5-grade scale) scores and quantitative parameters (signal-to-noise ratio [SNR] and contrast-to-noise ratio [CNR]) were assessed as image quality. The sensitivity, specificity, and accuracy of myocardial CT-LE were evaluated at the segment level using an American Heart Association (AHA) 16-segment model, with LGE-MRI as a reference standard. These results were compared among the different CT image reconstructions. In 28 patients with 448 segments, 160 segments were diagnosed with positive by LGE-MRI. In the qualitative assessment of myocardial CT-LE, the mean image quality scores were 2.9 ± 1.2 for HIR, 3.0 ± 1.1 for MBIR_cardiac, and 4.0 ± 1.0 for MBIR_myo. MBIR_myo showed a significantly higher score than HIR (P < 0.001) and MBIR_cardiac (P = 0.018). In the quantitative image quality assessment of myocardial CT-LE, the median image SNR was 10.3 (9.1-11.1) for HIR, 10.8 (9.8-12.1) for MBIR_cardiac, and 16.8 (15.7-18.4) for MBIR_myo. The median image CNR was 3.7 (3.0-4.6) for HIR, 3.8 (3.2-5.1) for MBIR_cardiac, and 6.4 (5.0-7.7) for MBIR_myo. MBIR_myo significantly improved the SNR and CNR of CT-LE compared to HIR and MBIR_cardiac (P < 0.001). The sensitivity, specificity, and accuracy for the detection of myocardial CT-LE were 70%, 92%, and 84% for HIR; 71%, 92%, and 85% for MBIR_cardiac; and 84%, 92%, and 89% for MBIR_myo, respectively. MBIR_myo showed significantly higher image quality, sensitivity, and accuracy than the others (P < 0.05). MBIR tuned for myocardium improved image quality and diagnostic performance for myocardial CT-LE assessment.

Expression of Circulating miR-21 and -29 and their Association with Myocardial Fibrosis in Hypertrophic Cardiomyopathy.

Hypertrophic Cardiomyopathy (HCM) is characterized by myocardial hypertrophy, fibrosis, and sarcomeric disarray. To evaluate the expression levels of circulating miR-21 and -29 in patients with HCM and their association with clinical characteristics and myocardial fibrosis. In this case-control study, 27 subjects with HCM, 13 subjects with hypertensive cardiomyopathy, and 10 control subjects were enrolled. Evaluation of patients' functional capacity was made by the six-minute walk test. Echocardiographic measurements of left ventricle systolic and diastolic function were conducted. Cardiac magnetic resonance late gadolinium enhancement (LGE) -through a semiquantitative evaluation- was used in the assessment of myocardial fibrosis extent in HCM patients. The expression of miR-21 and -29 in peripheral blood samples of all patients was measured via the method of quantitative reverse transcription polymerase chain reaction. Circulating levels of miR-21 were higher in both hypertensive and HCM (p<0.001) compared to controls, while expression of miR-29 did not differ between the three studied groups. In patients with HCM and LGE-detected myocardial fibrosis in more than 4 out of 17 myocardial segments, delta CT miR-21 values were lower than in patients with myocardial LGE in 3 or fewer myocardial segments (2.71 ± 1.06 deltaCT vs. 3.50 ± 0.55 deltaCT, p=0.04), indicating the higher expression of circulating miR-21 in patients with more extensive myocardial fibrosis. MiR-21 was overexpressed in patients with HCM and hypertensive cardiomyopathy. Importantly, in patients with HCM, more extensive myocardial fibrosis was associated with higher levels of miR-21.

Manifestation of conduction block zones by substrate mapping evaluated under multidirectional pacing during ventricular tachycardia ablation

Abstract Introduction Catheter ablation (CA) has proven to be effective therapy for ventricular tachycardia (VT) in patients with structural heart disease. However, activation mapping during VT is often limited in case of non-inducible, non-sustained or hemodynamically tolerable. It has been reported that a substrate-based approach for identifying conduction block and slow-conducting sites during sinus rhythm and ventricular pacing is promising strategies for CA. However, detailed analysis on the effectiveness of substrate mapping with multidirectional pacing to identify critical isthmus in unmappable VT have been lacking. Purpose The purpose of the present study was to evaluate the effectiveness of substrate mapping with multidirectional pacing in VT ablation. Methods From April 2022 to July 2023, 7 consecutive patients (4 men, age 62±9years) who underwent CA of VTs at our institute were enrolled. Isochronal late activation mapping (ILAM) was performed during sinus rhythm, right ventricular (RV) and left ventricular (LV) pacing. Cardiovascular magnetic resonance were performed in 3 of 7 cases to assess the distribution of myocardial late gadolinium enhancement. For catheter ablation, 2Fr electrode catheter was inserted into the anterior interventricular vein (AIV) at the distal site of the coronary sinus. LV pacing was performed using an electrode catheter placed in the AIV. ILAM were constructed by annotating the last deflection of each electrogram. Results In the 7 patients, 5 had ischemic cardiomyopathy and 2 had non-ischemic cardiomyopathy (Figure 1). During sinus rhythm, a deceleration zone (DZ) was identified in only 1 of 7 cases, consistent with linear conduction block. RV pacing demonstrated DZ in 3 of 7 cases. LV pacing revealed DZ in 6 of 7 cases, all of which had conduction blocks. U-shaped conduction blocks, which was not detectable in activation mapping during sinus rhythm, was newly identified in 29% of RV pacing, 71% of LV pacing. Combined RV and LV pacing unmasked the U-shaped conduction block in 86% of the cases. Only in case 7, activation mapping of VT with a cycle length of 470ms could be performed, and VT isthmus activation was observed in the area surrounded by the U-shaped conduction block (Figure 2). In other cases, the clinical VTs were unmappable because of the hemodynamic instability with tachycardia cycle length of approximately 300 milliseconds. Eventually, VTs became non-inducible in 3 of 5 cases in which induction was performed after the CA. During the follow-up period of 7±5 months, 6 of 7 cases remained free from any VT episodes. One patient showed small amount of pericardial effusion after CA. However, there were no life-threatening complications in any patients. Conclusion Substrate mapping using several different wavefront vectors in unstable VTs unveiled conduction block zones that might be potential ablation target sites for VT.Figure 1Figure 2

Diagnostic efficacy of complexity metrics from cardiac MRI myocardial segmental motion curves in detecting late gadolinium enhancement in myocardial infarction patients

BackgroundMyocardial segmental motion is associated with cardiovascular pathology, often assessed through myocardial strain features. The stability of the motion can be influenced by myocardial fibrosis. This research aimed to explore the complexity metrics (CM) of myocardial segmental motion curves, observe their correlation with late gadolinium enhancement (LGE) transmural extension (TE), and assess diagnostic efficacy combined with segmental strains in different TE segments. MethodsWe included 42 myocardial infarction patients, dividing images into 672 myocardial segments (208 remote, 384 viable, and 80 unviable segments based on TE). Radial and circumferential segmental strain, along with CM for motion curves, were extracted. Correlation between CM and LGE, as well as the potential distinguishing role of CM, was evaluated using Pearson correlation, univariate linear regression (F-test), multivariate regression analysis (T-test), area under curve (AUC), machine learning models, and DeLong test. ResultsAll CMs showed significant linear correlation with TE (P < 0.001). Six CMs were correlated with TE (r > 0.3), with radial frequency drift (FD) displayed the strongest correlation (r = 0.496, P < 0.001). Radial and circumferential FD significantly differed in higher TE myocardium than in remote segments (P < 0.05). Radial FD had practical diagnostic efficacy (remote vs. unviable AUC = 0.89, viable vs. unviable AUC = 0.77, remote vs. viable AUC = 0.65). Combining CM with segmental strain features boosted diagnostic efficacy than models using only segmental strain features (DeLong test, P < 0.05). ConclusionsThe CM of myocardial motion curves has been associated with LGE infarction, and combining CM with strain features improves the diagnosis of different myocardial LGE infarction degrees.

ENTRECTINIB–INDUCED ACUTE RIGHT HEART FAILURE IN A PATIENT WITH METASTATIC LUNG ADENOCARCINOMA

Abstract We report a case report of a 45–year–old woman with a recent diagnosis of stage IV lung adenocarcinoma (PDL1 60%) with brain metastases, who started entrectinib 600 mg orally once daily. Four days after entrectinib initiation, the patient activated the emergency medical services for acute onset of marked fatigue and hypotension. The ECG performed by the emergency unit showed a marked ST–segment elevation in the infero–lateral leads. Therefore, emergent coronary angiography was performed and no evidence of coronary disease was reported. Subsequently, the patient was admitted to the Coronary Care Unit. Clinical evaluation revealed labile hemodynamics, as the patient presented mental confusion, persistent hypotension (BP 90/50 mmHg) and bradycardia (HR 30 bpm). Laboratory testing showed elevated NT–pro BNP, troponin I and transaminases, normal CRP. The electrocardiogram showed persistent diffuse ST–segment elevation. Transthoracic echocardiogram showed severe dilatation and hypokinesia of the right ventricular (GLS VDx –4.5%), with diastolic “D–shape”, normal left ventricular ejection fraction, no significant valvular disease, circumferential pericardial effusion. Clinical, laboratory and instrumental findings suggested a condition of acute right heart failure. We performed urgent computed tomography pulmonary angiography (CTPA) which resulted negative for acute pulmonary embolism. Hence, supportive therapy with dobutamine, norepinephrine and fluid resuscitation was started, with subsequent hemodynamic stabilization. Since no other etiology was demonstrated by the extensive testing, we attributed the acute right ventricular dysfunction to the recent introduction of entrectinib therapy. Therefore, the drug was discontinued. During the hospitalization we observed a rapid normalization of electrocardiogram and right ventricle function by transthoracic echocardiogram, accompanied by a progressive improvement of laboratory parameters. In order to better define right ventricle function and dimension, the patient underwent cardiac magnetic resonance imaging which showed a normal right ventricle ejection fraction (RV EF 52%), the absence of myocardial edema or late gadolinium enhancement and normal volume of the right ventricle. After six days of hospitalization the patient was discharged. Our case report adds to the limited available literature of cardiac toxicity of entrectinib.

Cardiac Magnetic Resonance Imaging as a Risk Stratification Tool in COVID-19 Myocarditis.

The aim of this retrospective study was to identify myocardial injury after COVID-19 inflammation and explore whether myocardial damage could be a possible cause of the persistent symptoms following COVID-19 infection in previously healthy individuals. This study included 139 patients who were enrolled between January and June 2021, with a mean age of 46.7 ± 15.2 years, of whom 68 were men and 71 were women without known cardiac or pulmonary diseases. All patients underwent clinical work-up, laboratory analysis, cardiac ultrasound, and CMR on a 1.5 T scanner using a recommended protocol for morphological and functional assessment before and after contrast media application with multi-parametric sequences. In 39% of patients, late gadolinium enhancement (LGE) was found as a sign of myocarditis. Fibrinogen was statistically significantly higher in patients with LGE than in those without LGE (4.3 ± 0.23 vs. 3.2 ± 0.14 g/L, p < 0.05, respectively), as well as D-dimer (1.8 ± 0.3 vs. 0.8 ± 0.1 mg/L FEU). Also, troponin was statistically significantly higher in patients with myocardial LGE (13.1 ± 0.4 ng/L) compared to those with normal myocardium (4.9 ± 0.3 ng/L, p < 0.001). We demonstrated chest pain, fatigue, and elevated troponin to be independent predictors for LGE. Septal LGE was shown to be a predictor for arrhythmias. The use of CMR is a potential risk stratification tool in evaluating outcomes following COVID-19 myocarditis.

Evaluating a novel accelerated free-breathing late gadolinium enhancement imaging sequence for assessment of myocardial injury

IntroductionCardiac magnetic resonance imaging (MRI), including late gadolinium enhancement (LGE), plays an important role in the diagnosis and prognostication of ischemic and non-ischemic myocardial injury. Conventional LGE sequences require patients to perform multiple breath-holds and require long acquisition times. In this study, we compare image quality and assessment of myocardial LGE using an accelerated free-breathing sequence to the conventional standard-of-care sequence. MethodsIn this prospective cohort study, a total of 41 patients post Coronavirus 2019 (COVID-19) infection were included. Studies were performed on a 1.5 Tesla scanner with LGE imaging acquired using a conventional inversion recovery rapid gradient echo (conventional LGE) sequence followed by the novel accelerated free-breathing (FB-LGE) sequence. Image quality was visually scored (ordinal scale from 1 to 5) and compared between conventional and free-breathing sequences using the Wilcoxon rank sum test. Presence of per-segment LGE was identified according to the American Heart Association 16-segment myocardial model and compared across both conventional LGE and FB-LGE sequences using a two-sided chi-square test. The perpatient LGE extent was also evaluated using both sequences and compared using the Wilcoxon rank sum test. Interobserver variability in detection of per-segment LGE and per-patient LGE extent was evaluated using Cohen's kappa statistic and interclass correlation (ICC), respectively. ResultsThe mean acquisition time for the FB-LGE sequence was 17 s compared to 413 s for the conventional LGE sequence (P < 0.001). Assessment of image quality was similar between both sequences (P = 0.19). There were no statistically significant differences in LGE assessed using the FB-LGE versus conventional LGE on a per-segment (P = 0.42) and per-patient (P = 0.06) basis. Interobserver variability in LGE assessment for FB-LGE was good for per-segment (= 0.71) and per-patient extent (ICC = 0.92) analyses. ConclusionsThe accelerated FB-LGE sequence performed comparably to the conventional standard-of-care LGE sequence in a cohort of patients post COVID-19 infection in a fraction of the time and without the need for breath-holding. Such a sequence could impact clinical practice by increasing cardiac MRI throughput and accessibility for frail or acutely ill patients unable to perform breath-holding.

Liver T1 Mapping Derived From Cardiac Magnetic Resonance Imaging: A Potential Prognostic Marker in Idiopathic Dilated Cardiomyopathy.

Hepatic alterations are common aftereffects of heart failure (HF) and ventricular dysfunction. The prognostic value of liver injury markers derived from cardiac MRI studies in nonischemic dilated cardiomyopathy (DCM) patients is unclear. Evaluate the prognostic performance of liver injury markers derived from cardiac MRI studies in DCM patients. Prospective. Three hundred fifty-six consecutive DCM patients diagnosed according to ESC guidelines (age 48.7 ± 14.2 years, males 72.6%). Steady-state free precession, modified Look-Locker inversion recovery T1 mapping and phase sensitive inversion recovery late gadolinium enhancement (LGE) sequences at 3 T. Clinical characteristics, conventional MRI parameters (ventricular volumes, function, mass), native myocardial and liver T1, liver extracellular volume (ECV), and myocardial LGE presence were assessed. Patients were followed up for a median duration of 48.3 months (interquartile range 42.0-69.9 months). Primary endpoints included HF death, sudden cardiac death, heart transplantation, and HF readmission; secondary endpoints included HF death, sudden cardiac death, and heart transplantation. Models were developed to predict endpoints and the incremental value of including liver parameters assessed. Optimal cut-off value was determined using receiver operating characteristic curve and Youden method. Survival analysis was performed using Kaplan-Meier and Cox proportional hazard. Discriminative power of models was compared using net reclassification improvement and integrated discriminatory index. P value <0.05 was considered statistically significant. 47.2% patients reached primary endpoints; 25.8% patients reached secondary endpoints. Patients with elevated liver ECV (cut-off 34.4%) had significantly higher risk reaching primary and secondary endpoints. Cox regression showed liver ECV was an independent prognostic predictor, and showed independent prognostic value for primary endpoints and long-term HF readmission compared to conventional clinical and cardiac MRI parameters. Liver ECV is an independent prognostic predictor and may serve as an innovative approach for risk stratification for DCM. 1 TECHNICAL EFFICACY: Stage 2.

Insights into the effects of Friedreich ataxia on the left ventricle using T1 mapping and late gadolinium enhancement.

The left ventricular (LV) changes which occur in Friedreich ataxia (FRDA) are incompletely understood. Cardiac magnetic resonance (CMR) imaging was performed using a 1.5T scanner in subjects with FRDA who are homozygous for an expansion of an intron 1 GAA repeat in the FXN gene. Standard measurements were performed of LV mass (LVM), LV end-diastolic volume (LVEDV) and LV ejection fraction (LVEF). Native T1 relaxation time and the extracellular volume fraction (ECV) were utilised as markers of left ventricular (LV) diffuse myocardial fibrosis and late gadolinium enhancement (LGE) was utilised as a marker of LV replacement fibrosis. FRDA genetic severity was assessed using the shorter FXN GAA repeat length (GAA1). There were 93 subjects with FRDA (63 adults, 30 children, 54% males), 9 of whom had a reduced LVEF (<55%). A LVEDV below the normal range was present in 39%, a LVM above the normal range in 22%, and an increased LVM/LVEDV ratio in 89% subjects. In adults with a normal LVEF, there was an independent positive correlation of LVM with GAA1, and a negative correlation with age, but no similar relationships were seen in children. GAA1 was positively correlated with native T1 time in both adults and children, and with ECV in adults, all these associations independent of LVM and LVEDV. LGE was present in 21% of subjects, including both adults and children, and subjects with and without a reduced LVEF. None of GAA1, LVM or LVEDV were predictors of LGE. An association between diffuse interstitial LV myocardial fibrosis and genetic severity in FRDA was present independently of FRDA-related LV structural changes. Localised replacement fibrosis was found in a minority of subjects with FRDA and was not associated with LV structural change or FRDA genetic severity in subjects with a normal LVEF.

Clinical and Echocardiographic Predictors for the Presence of Late Gadolinium Enhancement on Cardiac Magnetic Resonance Imaging in Patients with Carbon Monoxide Poisoning.

Late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMRI) reflects the burden of myocardial damage in carbon monoxide (CO) poisoning. This study aimed to identify the clinical and echocardiographic parameters that can predict myocardial LGE on CMRI in CO poisoning. This prospective observational study included patients who presented with acute CO poisoning and elevated troponin I and underwent echocardiography and CMRI to identify myocardial damage at a tertiary university hospital between August 2017 and May 2019 and August 2020 and July 2022. Based on the CMRI findings, participants were categorized into LGE and non-LGE groups. The median age of the 155 patients was 51.0 years, and 98 (63.2%) were males. Median times from emergency department arrival to either CMRI or echocardiography were 3.0 days each. The LGE group included 99 (63.9%) patients with LGE positivity on CMRIs. Time from rescue to hyperbaric oxygen therapy >4 h (odds ratio (OR): 3.31, 95% confidence interval (CI): 1.28-8.56, p = 0.01); serum lactate levels >2 mmol/L (OR: 2.62, 95% CI: 1.20-5.73, p = 0.02); and left ventricular global longitudinal strain >-16% (OR: 2.95, 95% CI: 1.35-6.47, p = 0.007) were significant predictors of LGE positivity. The area under the curve of these predictors was 0.711. Our prediction model, which combines the clinical parameters with left ventricular global longitudinal strain, may be helpful in the early detection of LGE positivity.

Deep learning for classification of late gadolinium enhancement lesions based on the 16-segment left ventricular model

PurposeThis study aimed to develop and validate a deep learning-based method that allows for segmental analysis of myocardial late gadolinium enhancement (LGE) lesions. MethodsCardiac LGE data from 170 patients with coronary artery disease and non-ischemic heart disease were used for training, validation, and testing. Short-axis images were transformed to polar space after identification of the left ventricular (LV) center point and anterior right ventricular (RV) insertion point. Images were obtained after dividing the polar transformed images into segments based on the 16-segment LV model. Five different deep convolutional neural network (CNN) models were developed and validated using the labeled data, where the image after the division corresponded to a segment, and the lesion labeling was based on the 16-segment LV model. Unseen testing data were used to evaluate the performance of the lesion classification. ResultsWithout manual lesion segmentation and annotation, the proposed method showed an area under the curve (AUC) of 0.875, and a precision, recall, and F1-score of 0.723, 0.783, and 0.752, respectively for the lesion class when the pretrained ResNet50 model was tested for all slice images. The two pretrained models of ResNet50 and EfficientNet-B0 outperformed the three non-pretrained CNN models in terms of AUCs (0.873–0.875 vs. 0.834–0.841). ConclusionThe proposed method is based on learning a deep CNN model from polar transformed images to predict LGE lesions with good accuracy and does not require time-consuming annotation procedures such as lesion segmentation.

Late gadolinium enhancement following Covid-19 infection does not predict outcome: a single-centre study

Abstract Background Some patients are found to have myocardial scarring after infection with coronavirus-2019 disease (COVID-19) as evidenced by the presence of late gadolinium enhancement on cardiac MRI (CMR). In many types of heart disease, the presence of late gadolinium enhancement (even without symptoms) is associated with a poorer prognosis. However, it is not known whether the presence of scar after COVID-19 is associated with outcome. Purpose This study explores the association between late gadolinium enhancement (LGE) in recovered patients with COVID-19 and of longer-term clinical outcomes. Methods In this single-centre, retrospective, observational cohort study, troponin levels, CMR data, and follow-up outcomes of 169 patients with COVID-19 were collected. The primary outcome was all-cause mortality. The secondary outcome was a composite of myocardial infarction, stroke, and admission for heart failure. The log-rank test was used to compare survival of those with and without late gadolinium enhancement. Results A total of 169 patients (mean age 61 ± 16 years, 54% male) were included. Scans were typically performed in patients with a raised troponin or ongoing cardiac symptoms post COVID-19 infection. The median (IQR) time between COVID-19 diagnosis and CMR was 14 (7-23) weeks. Median follow-up was 28 (IQR 23 to 37) months. Troponin was performed in 92% (n=155) of patients. Of those, 78% (n=121) had a positive result. Late gadolinium enhancement was present in 54 patients (32%). There were no observed differences in comorbidities such as hypertension, known ischaemic heart disease or heart failure, diabetes, obesity, or frailty between in patients with LGE compared to those without LGE. Kaplan-Meier survival analysis showed no significant difference in all cause mortality for patients with COVID-19 with LGE compared to those without LGE (Log-rank P = 0.36). Similarly, the composite secondary endpoint was not significantly different (Log-rank P = 0.48). Conclusion In this single centre study, patients found to have myocardial LGE after COVID-19 did not have an increased risk of mortality or cardiovascular events compared to those without. The overall event rates remain low even after 2-3 years of follow-up. The cause of this is unclear but underlines the importance of larger multicentre studies to follow-up COVID-19 survivors.

Abstract 13074: Incremental Value of Abnormal Quantitative Myocardial Perfusion and Myocardial Infarction Using Cardiovascular Magnetic Resonance as Prognostic Markers in Type 2 Diabetes Mellitus

Introduction: Abnormal myocardial perfusion and MI are each associated with cardiovascular events in individuals with diabetes mellitus (DM). Hypothesis: We hypothesised that, in patients with T2DM, CMR determined quantitative myocardial perfusion and MI are independent predictors of major adverse cardiovascular and cerebrovascular events (MACCE) and that the presence of both offers incremental prognostic value. Methods: A prospective multicentre cohort of individuals with T2DM and healthy controls underwent stress CMR with inline quantitative myocardial perfusion and late gadolinium enhancement (LGE). Adjusted cox proportional hazard models (adjusted for age, sex, LVEF, LV end diastolic volume (LVEDV) and LV mass quantified associations between quantitative myocardial perfusion and MI with MACCE (composite of all-cause death, MI, stroke, heart failure hospitalisation and coronary revascularisation). Results: A total of 572 participants with T2DM from four centres and 52 healthy controls were followed for a median of 851 (IQR 765-935) days, during which 82 (14%) participants accrued at least one MACCE, including 25 (4%) deaths. Presence of either CMR pathology was associated with increased MACCE (normal quantitative myocardial perfusion and no MI: 7% MACCE; abnormal quantitative myocardial perfusion or MI: 13% MACCE (adjusted HR compared with normal 2.06 (95% CI 1.07-3.97, p=0.03)); and both abnormal quantitative myocardial perfusion and MI was associated with the highest event rate: 28% MACCE (adjusted HR compared with normal quantitative myocardial perfusion and no MI 4.55 (95% CI 2.32-8.90, p&lt;0.001)). Conclusion: In individuals with T2DM, the presence of either abnormal quantitative myocardial perfusion or MI is associated with MACCE and the presence of both offers strong incremental prognostic value.

Stress Perfusion Cardiac Magnetic Resonance vs SPECT Imaging for Detection of Coronary Artery Disease

BackgroundGadaCAD2 was 1 of 2 international, multicenter, prospective, Phase 3 clinical trials that led to U.S. Food and Drug Administration approval of gadobutrol to assess myocardial perfusion and late gadolinium enhancement (LGE) in adults with known or suspected coronary artery disease (CAD). ObjectivesA prespecified secondary objective was to determine if stress perfusion cardiovascular magnetic resonance (CMR) was noninferior to single-photon emission computed tomography (SPECT) for detecting significant CAD and for excluding significant CAD. MethodsParticipants with known or suspected CAD underwent a research rest and stress perfusion CMR that was compared with a gated SPECT performed using standard clinical protocols. For CMR, adenosine or regadenoson served as vasodilators. The total dose of gadobutrol was 0.1 mmol/kg body weight. The standard of reference was a 70% stenosis defined by quantitative coronary angiography (QCA). A negative coronary computed tomography angiography could exclude CAD. Analysis was per patient. CMR, SPECT, and QCA were evaluated by independent central core lab readers blinded to clinical information. ResultsParticipants were predominantly male (61.4% male; mean age 58.9 ± 10.2 years) and were recruited from the United States (75.0%), Australia (14.7%), Singapore (5.7%), and Canada (4.6%). The prevalence of significant CAD was 24.5% (n = 72 of 294). Stress perfusion CMR was statistically superior to gated SPECT for specificity (P = 0.002), area under the receiver operating characteristic curve (P < 0.001), accuracy (P = 0.003), positive predictive value (P < 0.001), and negative predictive value (P = 0.041). The sensitivity of CMR for a 70% QCA stenosis was noninferior and nonsuperior to gated SPECT. ConclusionsVasodilator stress perfusion CMR, as performed with gadobutrol 0.1 mmol/kg body weight, had superior diagnostic accuracy for diagnosis and exclusion of significant CAD vs gated SPECT.

Imaging Acute and Chronic Cardiac Complications of COVID-19 and after COVID-19 Vaccination.

COVID-19 is associated with acute and longer-term cardiovascular manifestations including myocardial injury, myopericarditis, stress-induced cardiomyopathy, myocardial infarction, and thromboembolic disease. Although the morbidity and mortality related to acute COVID-19 have decreased substantially, there is growing concern about the longer-term cardiovascular effects of the disease and postacute sequelae. Myocarditis has also been reported after messenger ribonucleic acid (mRNA)-based COVID-19 vaccination, with the highest risk among adolescent boys and young adult men. Noninvasive imaging including cardiac MRI has a key role in identifying the presence of cardiovascular disease, evaluating for potential mechanisms of injury, stratifying risk of future adverse cardiovascular events, and potentially guiding treatment in patients with suspected cardiovascular injury after COVID-19 and vaccination. Patterns of injury identified at cardiac MRI after COVID-19 include myocarditis and pericarditis, myocardial ischemia, and infarction. Myocardial edema and late gadolinium enhancement have been described months after the initial infection in a minority of patients with persistent cardiac symptoms after COVID-19. In patients with myocarditis after receiving a COVID-19 vaccination, the most common pattern of late gadolinium enhancement is subepicardial at the basal inferolateral wall, and patients tend to have milder imaging abnormalities compared with those from other causes of myocarditis. This article describes the role of multimodality cardiac imaging and imaging findings in patients with acute and longer-term cardiovascular manifestations of COVID-19 and in patients with myocarditis after receiving an mRNA-based COVID-19 vaccination. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

Dark papillary muscles sign: a novel prognostic marker for cardiac magnetic resonance

Abstract Funding Acknowledgements Type of funding sources: None. Background the prognostic role of left ventricular (LV) papillary muscle abnormalities in patients with preserved LV systolic ejection fraction (LVEF) is unknown. Aim to evaluate the prevalence and the clinical and prognostic impact of papillary muscle abnormalities by CMR in patients with ventricular arrhythmias, preserved LVEF with no cardiac disease. Methods 391 patients with &amp;gt;500/24h premature ventricular complexes and/or with non-sustained ventricular tachycardia (NSVT), preserved LVEF and no cardiac disease, were enrolled. Different features of LV papillary muscles were considered: supernumerary muscles, papillary thickness, the attachment, late gadolinium enhancement (LGE). The end-systolic hypointensity was defined when its measured signal intensity (SI) was lower than the SI of the septum in early post-contrast cine CMR images. Dark-Paps was defined when both the main papillary muscles had systolic hypointensity. Mitral valve prolapse, mitral annular disjunction (MAD), myocardial LGE were considered. The outcome of hard cardiac events was define as a composite of cardiac death, resuscitated cardiac arrest, and appropriate implantable cardioverter defibrillator (ICD) shock, sustained ventricular tachycardia (lasting ≥30 s at ≥100 beats/min). Results Dark-Paps was found in 79 (20%) patients and was more frequent in females. It was associated with higher prevalence of mitral valve prolapse and MAD. During a median follow-up of 2534 days, 22 hard cardiac events occurred. At Kaplan-Meier curve (Figure) analysis patients with Dark-Paps were at higher risk of events than those without (p&amp;lt;0.0001). Dark-Paps was significantly associated with hard cardiac events in all the multivariate models performed. Dark-Paps improved prognostic estimation when added to NSVT (p = 0.0006), to LGE (p = 0.005) and to a model including NSVT+LGE (p = 0.014). Dark-Paps allowed a significant net reclassification when added to NSVT (NRI 0.30, p =0.03), to LGE (NRI 0.25, p =0.04), and to NSVT + LGE (NRI 0.32, p =0.02). Conclusions Dark-Paps sign could be considered a novel imaging prognostic marker in patients with ventricular arrhythmias and preserved ejection fraction.

CMR reclassifies patients with suspected myocardial infarction with non-obstructive coronary arteries (MINOCA)

Abstract Funding Acknowledgements Type of funding sources: None. Objectives This study sought to assess the role of cardiac magnetic resonance (CMR) in investigating patients presenting with suspected acute coronary syndrome (ACS) and non-obstructed coronary arteries. Methods Consecutive patients presenting to a tertiary cardiology centre with suspected ACS and non-obstructed coronary arteries and referred for CMR were retrospectively identified. A comprehensive imaging protocol was performed to include cines, T2-weighted, and late gadolinium enhancement (LGE) sequences. Final CMR diagnosis was based on established patterns of tissue characterisation from myocardial oedema and LGE imaging, with patients grouped into five: myocardial infarction, myocarditis, Takotsubo syndrome, cardiomyopathy, and a normal CMR. Results A total of 888 patients were identified. The mean age across the cohort was 57 years (SD ±15.9 years) with 51% female patients. Median time to CMR from acute presentation was 21 days (Figure 1). Aetiology of presentation was uncertain in more than half of patients referred for CMR (483, 54.1%). Of patients with an initial uncertain aetiology, CMR was able to identify an underlying diagnosis in 74.9%. Diagnosis across the whole cohort was reclassified in 691 patients (77.8%), with overall diagnostic yield (CMR identified underlying aetiology for presentation) of 75.6%. (Figure 2). Conclusions In a large single-centre cohort of patients presenting with suspected ACS and non-obstructed coronary arteries, diagnostic yield with CMR was high at 76%. CMR reclassified nearly 80% of patients. Our results highlight the importance of CMR in the diagnostic pathway of suspected ACS and potential implications on clinical management.

Cardiac fibroblast activation after acute myocardial infarction: pilot study using technetium 99m-iFAP SPECT

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): Instituto Nacional de Investigaciones Nucleares (ININ). Background/Introduction Excessive fibrosis and persistent active fibroblasts can lead to increased left ventricular stiffness and, thus, heart failure. Cardiac remodeling is an important factor in the prognosis of patients after an acute myocardial infarction (AMI), and fibroblast activation is mandatory for repair and regeneration of the damage. There's an increasing use of molecular imaging in cardiovascular processes, such as molecules targeting fibroblast activation protein (FAP). FAP inhibitors (iFAP) radiolabeled with 68Ga in PET/CT have demonstrated adequate biodistribution and high uptake by activated fibroblasts in patients with cardiovascular risk factors and after acute myocardial infarction. Unfortunately, PET is not always widely available or cost-effective. Purpose This pilot study evaluates the feasibility of imaging activated fibroblast using 99mTc-iFAP SPECT in patients after AMI and its correlation with myocardial perfusion imaging (MPI), cardiac magnetic resonance (CMR) and invasive coronary angiography (ICA). Methods A prospective study with recent first AMI and non-previous known coronary artery disease patients were included. They underwent 99mTc-MIBI MPI SPECT and 99mTc-iFAP SPECT (including whole-body scan and thorax anterior static image acquired at 20, 60, and 120 min for the iFAP) and CMR/ICA within 14 days (+-2) after AMI. Qualitative and quantitative analysis was performed using a 17 segments model using QPS (Cedars Sinai) to determine the infarct extension from MPI and the correlation with the 99mTc-iFAP uptake pattern. A visual grading scale was established to assess localized tracer uptake and segments belonging to the hypoperfused area of the culprit's vessel. CMR yielded an area of injury with late gadolinium enhancement (LGE) and correlated with MPI studies. Results Five patients with STEMI were included (mean age of 63). Localized uptake of 99mTc-iFAP was observed in all patients with according to the affected coronary territory detected by ICA in 100% of patients (four anterior STEMI, one inferior STEMI). No radiotracer uptake was observed in the non-infarcted territories. Agreement between myocardial iFAP uptake, MIBI myocardial perfusion defect, CMR LGE, and ICA findings are presented in figure 1. An agreement of mismatch in polar maps between iFAP and MPI was performed, obtaining an excellent mismatch pattern in all patients, especially in transmural infarct segments. The best quality image was obtained at 60 minutes. Conclusions We successfully carried out the first pilot study with the patented 99mTc-iFAP molecule with SPECT technique. 99mTc-iFAP is a promising novel biomarker in assessing myocardial injury in sites where PET/CT is unavailable. There is an excellent correlation between iFAP uptake with the perfusion defect, LGE, and invasive anatomical obstruction findings. It is feasible and necessary to extend the inclusion of patients to a larger sample.

Diagnostic and Prognostic Value of Stress Cardiovascular Magnetic Resonance Imaging in Patients With Known or Suspected Coronary Artery Disease

The clinical utility of stress cardiovascular magnetic resonance imaging (CMR) in stable chest pain is still debated, and the low-risk period for adverse cardiovascular (CV) events after a negative test result is unknown. To provide contemporary quantitative data synthesis of the diagnostic accuracy and prognostic value of stress CMR in stable chest pain. PubMed and Embase databases, the Cochrane Database of Systematic Reviews, PROSPERO, and the ClinicalTrials.gov registry were searched for potentially relevant articles from January 1, 2000, through December 31, 2021. Selected studies evaluated CMR and reported estimates of diagnostic accuracy and/or raw data of adverse CV events for participants with either positive or negative stress CMR results. Prespecified combinations of keywords related to the diagnostic accuracy and prognostic value of stress CMR were used. A total of 3144 records were evaluated for title and abstract; of those, 235 articles were included in the full-text assessment of eligibility. After exclusions, 64 studies (74 470 total patients) published from October 29, 2002, through October 19, 2021, were included. This systematic review and meta-analysis adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Diagnostic odds ratios (DORs), sensitivity, specificity, area under the receiver operating characteristic curve (AUROC), odds ratio (OR), and annualized event rate (AER) for all-cause death, CV death, and major adverse cardiovascular events (MACEs) defined as the composite of myocardial infarction and CV death. A total of 33 diagnostic studies pooling 7814 individuals and 31 prognostic studies pooling 67 080 individuals (mean [SD] follow-up, 3.5 [2.1] years; range, 0.9-8.8 years; 381 357 person-years) were identified. Stress CMR yielded a DOR of 26.4 (95% CI, 10.6-65.9), a sensitivity of 81% (95% CI, 68%-89%), a specificity of 86% (95% CI, 75%-93%), and an AUROC of 0.84 (95% CI, 0.77-0.89) for the detection of functionally obstructive coronary artery disease. In the subgroup analysis, stress CMR yielded higher diagnostic accuracy in the setting of suspected coronary artery disease (DOR, 53.4; 95% CI, 27.7-103.0) or when using 3-T imaging (DOR, 33.2; 95% CI, 19.9-55.4). The presence of stress-inducible ischemia was associated with higher all-cause mortality (OR, 1.97; 95% CI, 1.69-2.31), CV mortality (OR, 6.40; 95% CI, 4.48-9.14), and MACEs (OR, 5.33; 95% CI, 4.04-7.04). The presence of late gadolinium enhancement (LGE) was associated with higher all-cause mortality (OR, 2.22; 95% CI, 1.99-2.47), CV mortality (OR, 6.03; 95% CI, 2.76-13.13), and increased risk of MACEs (OR, 5.42; 95% CI, 3.42-8.60). After a negative test result, pooled AERs for CV death were less than 1.0%. In this study, stress CMR yielded high diagnostic accuracy and delivered robust prognostication, particularly when 3-T scanners were used. While inducible myocardial ischemia and LGE were associated with higher mortality and risk of MACEs, normal stress CMR results were associated with a lower risk of MACEs for at least 3.5 years.

P403 MITRAL VALVE PROLAPSE AND RISK OF SUDDEN CARDIAC DEATH IN A PATIENT WITH VENTRICULAR ARRHYTHMIAS: THE PROGNOSTIC ROLE OF CARDIAC MAGNETIC RESONANCE IMAGING

Abstract Introduction in most cases mitral valve prolapse is a benign condition, however in 2% of cases it has been associated with the risk of sudden cardiac death (SCD). Basso et al have demonstrated papillary muscle’s and left ventricle’s inferolateral wall fibrosis on cardiac magnetic resonance imaging (MRI), in patients who died from SCD with mitral valve prolapse. Clinical case A 59–year–old patient was admitted to the Cardiology Department of Pertini Hospital (Rome, Italy) for episodes of vertigo and not sustained ventricular tachycardia in two morphologies at 24–hour ECG monitoring. The patient had negative history for cardiovascular risk factors, but an echocardiogram had demonstrated a moderate mitral valve regurgitation, secondary to valve prolapse with mitral annular disjunction (MAD) (Fig.1). Considering patient‘s age associated with low pre–test probability of coronary artery disease, the patient underwent coronary CT that showed a coronary artery tree free from injury. Cardiac MRI showed increased volumes in the left ventricle and slightly reduced systolic function and valve prolapse of both mitral leaflets determining moderate regurgitation. In addition, intra–myocardial Late Gadolinium Enhancement (LGE) showed fibrosis of the inferior and inferolateral wall with extension to the proximal portion of the inferior papillary muscle (Fig.2). Considering such findings, an intracavitary electrophysiological study (EPS) was performed for an evaluation of the arhythmic burden, by administrating the patient a double extra stimulus from the outflow tract of the right ventricle; the treatment induced a polymorphic ventricular tachycardia, starting from the inferior papillary muscle and degenerating into ventricular fibrillation (Fig.3). Discussion considering all the above findings, a mitral valve prolapse at high risk of malignant arrhythmias has been diagnosed and a subcutaneous cardiac defibrillator was implanted. Conclusions in mitral valve prolapse associated with complex ventricular arrhythmias, evaluation with cardiac MRI increasingly plays a crucial role in prognostic stratification for defibrillator implantation in primary prevention.