Early Gadolinium Enhancement Imaging Research Articles

Comprehensive Cardiovascular Magnetic Resonance Tissue Characterization and Cardiotoxicity in Women With Breast Cancer

There is a growing interest in understanding whether cardiovascular magnetic resonance (CMR) myocardial tissue characterization helps identify risk of cancer therapy-related cardiac dysfunction (CTRCD). To describe changes in CMR tissue biomarkers during breast cancer therapy and their association with CTRCD. This was a prospective, multicenter, cohort study of women with ERBB2 (formerly HER2)-positive breast cancer (stages I-III) who were scheduled to receive anthracycline and trastuzumab therapy with/without adjuvant radiotherapy and surgery. From November 7, 2013, to January 16, 2019, participants were recruited from 3 University of Toronto-affiliated hospitals. Data were analyzed from July 2021 to June 2022. Sequential therapy with anthracyclines, trastuzumab, and radiation. CMR, high-sensitivity cardiac troponin I (hs-cTnI), and B-type natriuretic peptide (BNP) measurements were performed before anthracycline treatment, after anthracycline and before trastuzumab treatment, and at 3-month intervals during trastuzumab therapy. CMR included left ventricular (LV) volumes, LV ejection fraction (EF), myocardial strain, early gadolinium enhancement imaging to assess hyperemia (inflammation marker), native/postcontrast T1 mapping (with extracellular volume fraction [ECV]) to assess edema and/or fibrosis, T2 mapping to assess edema, and late gadolinium enhancement (LGE) to assess replacement fibrosis. CTRCD was defined using the Cardiac Review and Evaluation Committee criteria. Fixed-effects models or generalized estimating equations were used in analyses. Of 136 women (mean [SD] age, 51.1 [9.2] years) recruited from 2013 to 2019, 37 (27%) developed CTRCD. Compared with baseline, tissue biomarkers of myocardial hyperemia and edema peaked after anthracycline therapy or 3 months after trastuzumab initiation as demonstrated by an increase in mean (SD) relative myocardial enhancement (baseline, 46.3% [16.8%] to peak, 56.2% [18.6%]), native T1 (1012 [26] milliseconds to 1035 [28] milliseconds), T2 (51.4 [2.2] milliseconds to 52.6 [2.2] milliseconds), and ECV (25.2% [2.4%] to 26.8% [2.7%]), with P <.001 for the entire follow-up. The observed values were mostly within the normal range, and the changes were small and recovered during follow-up. No new replacement fibrosis developed. Increase in T1, T2, and/or ECV was associated with increased ventricular volumes and BNP but not hs-cTnI level. None of the CMR tissue biomarkers were associated with changes in LVEF or myocardial strain. Change in ECV was associated with concurrent and subsequent CTRCD, but there was significant overlap between patients with and without CTRCD. In women with ERBB2-positive breast cancer receiving sequential anthracycline and trastuzumab therapy, CMR tissue biomarkers suggest inflammation and edema peaking early during therapy and were associated with ventricular remodeling and BNP elevation. However, the increases in CMR biomarkers were transient, were not associated with LVEF or myocardial strain, and were not useful in identifying traditional CTRCD risk.

593 Spontaneous coronary artery dissection in young

Abstract Aims We present the case of a 25 years-old patient, presented to the Emergency Department for chest pain and epigastralgia complicated by vomiting. Symptoms started about 30 h before, afterwards an effort. The patient did not have any known cardiovascular risk factors (except for sporadic consumption of cannabis) and family medical history was negative for premature cardiovascular disease or sudden cardiac death. His past medical history was unremarkable. Methods and results Clinical examination was normal. ECG was suggestive for subacute anterior ST-elevation myocardial infarction (QS in V1–V4 leads with ST segment elevation and biphasic T-waves in V4–V6) and was accompanied by significant elevation of myocardial necrosis biomarkers (hsTnT 3416 ng/l, n.v. &amp;lt;15). Echocardiography revealed a severely reduced left ventricular ejection fraction (LVEF = 30%) with regional wall motion abnormalities (apical and septal akinesia, and anterior mid-ventricular segment hypokinesia). Coronary angiography was suggestive for a dissection of the proximal-to-mid left anterior descending artery. Dissection flap, subocclusion of the first septal branch, and intramural thrombosis were noted. Direct stenting with drug-eluting stent was successful, with thrombolysis in myocardial infarction (TIMI) flow grade 3. The patient was started on dual antiplatelet treatment (aspirin and ticagrelor), ACE-inhibitors, beta blockers, and spironolactone. Further testing ruled out other conditions that may be associated with spontaneous coronary artery dissection (autoimmune diseases, including vasculitis, connective tissue disease, coagulative disorders). The clinical course was complicated by pericarditis and the development of LV apical thrombus. So, patient was started on anticoagulation (warfarin) with subsequently downgrading from ticagrelor to clopidogrel. Echocardiographic follow-up documented a progressive improvement of LVEF (50%), and global longitudinal strain (GLS −15%) with persistence of wall motion abnormalities in the apical and septal segments. Partial resolution of intracavitary thrombi was documented. CMR revealed LV apical aneurysm. Moreover, the use of dedicated sequences showed transmural late gadolinium enhancement in akinetic segments, and fatty metaplasia of the apical portion of the anterior wall and anterior septal wall. Finally, early gadolinium enhancement imaging, confirmed the persistence of LV stratified apical thrombus. Conclusions Spontaneous coronary artery dissection (SCAD) is an underdiagnosed and frequent cause of acute coronary syndrome (ACS) in young-to-middle aged patients, particularly women; therefore, even in young people, a chest pain episode suggestive for an ischaemic cause should never be underestimated. Cardiac magnetic resonance is the most accurate method to evaluate the sequelae of myocardial infarction (including LV size and function, presence of fatty metaplasia, extent and transmurality of ischaemic scar, presence of thrombi), to aid in differential diagnosis and to define prognosis and guide the therapeutic management.

Early myocardial gadolinium enhancement in patients with myocarditis: Validation of “Lake Louise consensus” criteria using a single bolus of 0.1 mmol/Kg of a high relaxivity gadolinium-based contrast agent

ObjectivesGlobal early gadolinium enhancement (EGE) is an accepted cardiac magnetic resonance (CMR) criterion for diagnosis of myocarditis. However, recommended enhancement thresholds are based specifically on standard-relaxivity Gd-chelates. We evaluated the performance of a high relaxivity MR contrast agent for detection of myocardial hyperemia in patients referred for endomyocardial biopsy (EMB). MethodsWe retrospectively enrolled 54 patients (mean age: 44.1 years [range=18–77years]; 72% men) with suspected myocarditis who underwent CMR and EMB within four weeks of clinical onset. CMR imaging protocol included T2-weighted short tau inversion-recovery sequence, EGE and late gadolinium enhanced (LGE) imaging.For EGE imaging, free-breathing ECG-gated turbo spin echo T1-weighted (TSE T1w) sequences were acquired before and within the first three minutes after gadobenate dimeglumine (0.1mmol/Kg) administration. The ratio (EGEr) between myocardial and musculoskeletal early enhancement was calculated. Myocardial edema, EGE and late gadolinium enhancement (LGE) were correlated with EMB results. Receiver operating characteristic (ROC) curve analysis of EGE values was applied on the overall population. ResultsEMB revealed myocarditis in 34/54 patients. Sensitivity, specificity and accuracy values of 0.61, 0.85 and 0.70, respectively, were obtained for a standard EGE threshold (EGEr>4.0). ROC analysis revealed an area under the curve of 0.701 for EGEr (IC95%:0.556–0.846, p=0.014) and 0.706 for absolute enhancement (IC95%:0.563–0.849, p=0.012).Sensitivity, specificity and accuracy values were 0.67, 0.80 and 0.72, respectively, for myocardial edema and 0.76, 0.75 and 0.76, respectively, for LGE. ConclusionsHigh relaxivity contrast agents provide comparable results to standard-relaxivity chelates for EGE assessment in diagnosing myocarditis.

Feasibility of detecting myocardial infarction in the sheep fetus using late gadolinium enhancement CMR imaging

BackgroundLate gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging has enabled the accurate assessment of myocardial infarction (MI). However, LGE CMR has not been performed successfully in the fetus, where it could be useful for animal studies of interventions to promote cardiac regeneration. We believe that LGE imaging could allow us to document the presence, extent and effect of MI in utero and would thereby expand our capacity for conducting fetal sheep MI research. We therefore aimed to investigate the feasibility of using LGE to detect MI in sheep fetuses.MethodsSix sheep fetuses underwent a thoracotomy and ligation of a left anterior descending (LAD) coronary artery branch; while two fetuses underwent a sham surgery. LGE CMR was performed in a subset of fetuses immediately after the surgery and three days later. Early gadolinium enhancement (EGE) CMR was also performed in a subset of fetuses on both days. Cine imaging of the heart was performed to measure ventricular function.ResultsThe imaging performed immediately after LAD ligation revealed no evidence of infarct on LGE (n=3). Two of four infarcted fetuses (50%) showed hypoenhancement at the infarct site on the EGE images. Three days after the ligation, LGE images revealed a clear, hyper-enhanced infarct zone in four of the five infarcted fetuses (80%). No hyper-enhanced infarct zone was seen on the one sham fetus that underwent LGE CMR. No hypoenhancement could be seen in the EGE images in either the sham (n=1) or the infarcted fetus (n=1). No regional wall motion abnormalities were apparent in two of the five infarcted fetuses.ConclusionLGE CMR detected the MI three days after LAD ligation, but not immediately after. Using available methods, EGE imaging was less useful for detecting deficits in perfusion. Our study provides evidence for the ability of a non-invasive tool to monitor the progression of cardiac repair and damage in fetuses with MI. However, further investigation into the optimal timing of LGE and EGE scans and improvement of the sequences should be pursued with the aim of expanding our capacity to monitor cardiac regeneration after MI in fetal sheep.

Early Gadolinium Enhancement for Determination of Area at Risk: A Preclinical Validation Study

ObjectivesThe aim of this study was to determine whether early gadolinium enhancement (EGE) by cardiac magnetic resonance (CMR) in a canine model of reperfused myocardial infarction depicts the area at risk (AAR) as determined by microsphere blood flow analysis. BackgroundIt remains controversial whether only the irreversibly injured myocardium enhances when CMR is performed in the setting of acute myocardial infarction. Recently, EGE has been proposed as a measure of the AAR in acute myocardial infarction because it correlates well with T2-weighted imaging of the AAR, but this still requires pathological validation. MethodsEleven dogs underwent 2 h of coronary artery occlusion and 48 h of reperfusion before imaging at 1.5-T. EGE imaging was performed 3 min after contrast administration with coverage of the entire left ventricle. Late gadolinium enhancement imaging was performed between 10 and 15 min after contrast injection. AAR was defined as myocardium with blood flow <2 SD from remote myocardium determined by microspheres during occlusion. The size of infarction was determined with triphenyltetrazolium chloride. ResultsThere was no significant difference in the size of enhancement by EGE compared with the size of AAR by microspheres (44.1 ± 15.8% vs. 42.7 ± 9.2%; p = 0.61), with good correlation (r = 0.88; p < 0.001) and good agreement by Bland-Altman analysis (mean bias 1.4 ± 17.4%). There was no difference in the size of enhancement by EGE compared with enhancement on native T1 and T2 maps. The size of EGE was significantly greater than the infarct by triphenyltetrazolium chloride (44.1 ± 15.8% vs. 20.7 ± 14.4%; p < 0.001) and late gadolinium enhancement (44.1 ± 15.8% vs. 23.5 ± 12.7%; p < 0.001). ConclusionsAt 3 min post-contrast, EGE correlated well with the AAR by microspheres and CMR and was greater than infarct size. Thus, EGE enhances both reversibly and irreversibly injured myocardium.

133 Early vs. Late Microvascular Obstruction Following Primary PCI- Two Pathologies or One?

BackgroundMicrovascular obstruction (MO) is a feature of 20–40% of reperfused acute ST-elevation myocardial infarction (STEMI), and confers adverse prognosis. Cardiovascular magnetic resonance (CMR) can visualise MO with high resolution and...

CMR techniques and findings in children with myocarditis: a multicenter retrospective study

Background CMR is increasingly used to diagnose myocarditis in adults but its use in pediatric-age pts is not well estab- lished. We sought to describe the clinical presentation, CMR imaging protocols, CMR findings, and outcomes in a multicenter cohort of children with myocarditis. Methods 71 studies (66%) and was abnormal in 49 (69%). First pass contrast perfusion (FPP) imaging was performed in 42 studies (45%) and was abnormal in 4 (10%). T1- weighted imaging for early gadolinium enhancement (EGE) was performed in 35 studies (37%) and was abnor- mal in 19 (51%). Late gadolinium enhancement (LGE) imaging was performed in all studies, and was abnormal in 93 (83%) with the following reported distributions: 89% subepicardial or midwall, 6% patchy, 3% sub-endo- cardial, 1% transmural, and 1% diffuse. The CMR study was interpreted as positive for myocarditis in 96 pts (87%), negative in 11 (10%), and equivocal in 4 (4%), yielding a sensitivity of 86% for an ultimate clinical diag- nosis of myocarditis. There was significant practice varia- tion in the use of T2W, FPP, and EGE imaging among the participating institutions (Figure 1). At a median fol- low-up time from CMR of 6 mo (0.2-217), all patients were alive and 3 had undergone cardiac transplantation, all of whom had CMR studies positive for myocarditis. Conclusions This is the largest study to date describing the CMR findings in children with myocarditis. The CMR techni- ques used, from most to least common, were LGE, T2W, FPP, and EGE. Abnormalities were most often seen with LGE followed by T2W, EGE, and FPP. There was significant practice variation in the CMR protocol between institutions. The information from this study should be useful in planning a prospective study to eval- uate the diagnostic and predictive performance of CMR in children with suspected myocarditis. Funding None.

Cardiac MRI in the Assessment of Cardiac Injury and Toxicity From Cancer Chemotherapy

During the past 30 years, there has been a significant decrease in cancer mortality rates, predominantly attributable to improvements in treatment options.1 However, survivors are at increased risk of premature cardiac disease,2 both because of the overlap in risk factors for cancer and cardiovascular disease3 and the cardiotoxic effects of cancer chemotherapy. Two chemotherapeutic agent classes that are commonly associated with cardiotoxicity are the anthracyclines and tyrosine kinase inhibitors, both of which can cause left ventricular (LV) dysfunction and heart failure (HF).4,5 Mechanisms of cardiac injury from cancer therapy have been summarized elsewhere.4,6 Briefly, anthracycline cardiotoxicity has been attributed to reactive oxygen species formation, transcriptional changes in intracellular adenosine triphosphate production in cardiac myocytes, and, more recently, through interaction with cardiac topoisomerase IIβ.4,6 Trastuzumab cardiotoxicity seems to be because of inhibition of cardiomyocyte human epidermal growth factor receptor 2, resulting in ATP depletion and contractile dysfunction.4 Other proposed mechanisms include immune-mediated destruction of cardiomyocytes.4,6 At the tissue level, early anthracycline toxicity has been associated with myocardial inflammation,7–9 vacuolization,9–12 and cell swelling/edema.11,13 These changes seem to occur before myocardial functional abnormalities.11,13 Later stages of toxicity are associated with myocardial fibrosis.14,15 Unfortunately, the use of myocardial biopsy is not feasible for diagnostic purposes in this setting. However, once HF manifests, the 2-year mortality can be as high as 60%.16 This emphasizes the importance of early recognition of cardiac injury and institution of cardioprotective therapy in an effort to prevent development of HF and allow uninterrupted completion of cancer therapy.17 Thus, the diagnosis is dependent on either direct evidence of myocardial damage or functional disturbance. Either signal may be identified …

Contrast-enhanced CMR is equally effective as TEE in the evaluation of left atrial appendage thrombus in patients with atrial fibrillation undergoing pulmonary vein isolation procedure

Patients with atrial fibrillation (AF) routinely undergo transesophageal echocardiography (TEE) for the evaluation of the left atrial appendage (LAA) to rule out thrombus prior to undergoing pulmonary vein isolation (PVI). Cardiac magnetic resonance (CMR) is now increasingly used for the evaluation of patients with AF to define pulmonary vein (PV) anatomy prior to PVI. To hypothesize that a retrospective comparison of 2-dimensional/3-dimensional (2D/3D) contrast-enhanced CMR sequences with TEE for the evaluation of LAA thrombus in patients with AF selected for PVI will demonstrate equivalence. Ninety-seven (N = 97) consecutive patients with AF underwent near-simultaneous TEE and noncontrast and contrast CMR prior to undergoing an initial PVI procedure. The CMR images were analyzed in 2 categories: (1) the 2D noncontrast cine images and early gadolinium enhancement images showing LAA and (2) 3D contrast source images acquired during PV magnetic resonance angiography. CMR variables evaluated were the presence or absence of LAA thrombus and the quality of images, and they were compared with the results of TEE in a blinded fashion. All subjects were analyzed for the presence or absence of LAA thrombus. Thrombus was absent in 98% of the patients on both TEE and CMR and present in 2% on both studies (100% correlation). In 6 subjects, 2D cine CMR images were indeterminate whereas all 2D early gadolinium enhancement images and 3D contrast images were successful in excluding LAA thrombus. There was 100% concordance between CMR and TEE for the final diagnosis of LAA thrombus. In one single examination, CMR offers a comparable alternative to TEE for the complete noninvasive evaluation of LAA thrombus and PV anatomy in patients with AF referred for PVI without obligate need for TEE.

Abstract 16686: Early Gadolinium Enhancement Represents Area at Risk Not Infarct Size: Timing and Kinetics Are Critical in Interpreting MRI of Acute Myocardial Infarction

Background: Recent papers have raised questions about whether gadolinium over-estimates infarct size and have indicated that early gadolinium enhancement (EGE) corresponds to the area at risk (AAR) rather than infarct size.Objective: To determine kinetics, timing, and size of early gadolinium enhancement as related to measurements of area at risk and infarct size in patients with acute myocardial infarction (MI). Methods: MRI was performed on 35 patients within 7 days of acute MI. T2-weighted images were acquired with bright blood methods to measure AAR. EGE images were acquired 1, 3, 5, and 7 minutes post-contrast with single-shot phase sensitive inversion recovery (PSIR). Late gadolinium enhanced (LGE) images were obtained 10-20 minutes post-contrast using segmented PSIR. EGE images were evaluated semi-quantitatively using a 2-SD threshold and with manual planimetry. LGE Infarct size was measured with the previously validated FACT algorithm. Microvascular obstruction was included in the hyperenhanced zone for EGE and LGE. Results: Of the 35 patients (26 were male, age 61±12 years old), 14 had subendocardial MI and 21 had transmural MI. For subendocardial MI, the correlation between EGE and T2-weighted AAR was only fair at 1 minute post contrast (r=0.68), but improved to (r=0.86-0.88) from 3 minutes to 7 minutes post-contrast administration. However, there was significant intersubject variability with regard to the optimal timing for EGE as a measure of AAR. For subendocardial MI, the best agreement between EGE and T2 weighted AAR occurred at 3 minutes in 4 subjects, 5 minutes in 4 subjects, and 7 minutes in 5 subjects. For transmural MI (n=21), the best agreement occurred at 7 minutes post-contrast. The maximal area of hyperenhancement on EGE correlated most closely with T2 AAR for subendocardial MI (r=0.91) and was significantly larger than MI size on LGE images (p&lt;0.001 for all MI and for subendocardial MI). Conclusion: Myocardial gadolinium enhancement kinetics influence the size of the hyperenhanced zone such that early gadolinium enhancement between 3-7 minutes closely correlates with area at risk, and thus can over-estimate infarct size for non-transmural MI. Timing is critical when quantifying acute infarct size with gadolinium enhanced MRI.

Evidence of an increased incidence of myocardial inflammation associated with reduced ventricular function in clinically suspected idiopathic dilated cardiomyopathy - a cardiovascular magnetic resonance study

Background Dilated cardiomyopathy (DCM) occurring due to an unknown etiology or genetic predisposition is termed as idiopathic dilated cardiomyopathy (iDCM), although iDCM may also result from viral exposure. However, the incidence of myocardial inflammation and its relation to left ventricular (LV) function in iDCM remains unknown. Cardiovascular magnetic resonance (CMR) imaging allows for the visualization of myocardial inflammation using early Gadolinium enhancement (EGE). We applied EGE imaging in the setting of clinically suspected iDCM to determine both the incidence and relation of myocardial inflammation to LV function.

Perilesional enhancement of hepatic metastases: correlation between MR imaging and histopathologic findings-initial observations.

To correlate perilesional enhancement on gadolinium-enhanced magnetic resonance (MR) images with histopathologic findings in patients with hepatic metastases. In seven patients with histopathologically proved hepatic metastases, MR images obtained before and early and late after the administration of gadopentetate dimeglumine were retrospectively evaluated for perilesional enhancement. The thickness of hepatic parenchyma with intense perilesional enhancement was calculated. The thickness of the histologic tumor border (the zone separating the outermost border of the tumor nodule from the surrounding hepatic parenchyma) also was measured. In three patients, early gadolinium-enhanced images showed prominent perilesional enhancement, which correlated with a thick tumor border containing peritumoral desmoplastic reaction, peritumoral inflammation, and vascular proliferation at histopathologic examination. In one patient, mild perilesional enhancement was shown. At histopathologic examination, the lesion periphery showed moderate peritumoral changes. In the remaining three patients, no perilesional enhancement was observed, and at histopathologic examination there was a thin tumor border that contained minimal to mild perilesional changes. The thickness of hepatic parenchyma with intense perilesional enhancement on early gadolinium-enhanced images showed a strong positive correlation with tumor border thickness at histopathologic examination (r = 0.99). Intense perilesional enhancement of metastases on early gadolinium-enhanced MR images correlates with histopathologic hepatic parenchymal changes, which include peritumoral desmoplastic reaction, inflammatory cell infiltration, and vascular proliferation.

Pyogenic hepatic abscesses: MRI findings on T1- and T2-weighted and serial gadolinium-enhanced gradient-echo images.

The purpose of this study was to determine the magnetic resonance imaging (MRI) features of pyogenic hepatic abscesses on T1-weighted, T2-weighted, and serial gadolinium (Gd)-enhanced T1-weighted spoiled gradient-echo (SGE) images including images acquired in the immediate, intermediate, and late phases of enhancement. The MRI studies of 20 patients with pyogenic liver abscesses were retrospectively reviewed. All patients were examined on 1.5 (n = 19) and 1.0 (n = 1) T MR scanners. MR studies included T1-weighted, T2-weighted, and serial Gd-enhanced SGE images. The following determinations were made: signal intensity of the abscess cavity and perilesional liver tissue, and the presence of internal septations, layering material, or air in the abscess cavity. The pattern of enhancement of the abscess wall, internal septae and peri-abscess liver were evaluated on serial Gd-enhanced SGE images. A total of 53 abscesses were observed in the 20 patients. Fortyeight abscesses were hypointense on T1-weighted and hyperintense on T2-weighted images. Internal septations were present in four abscesses. Lower signal intensity material was observed in a dependent location on T2-weighted images in one abscess. Signal void foci of air located on the nondependent surface was observed in two abscesses. Two other abscesses contained signal void air that occupied the entire abscess cavity, observed on all imaging sequences. On serial gadolinium-enhanced images, all abscesses revealed early enhancement of the wall, which persisted with negligible change in degree of enhancement or thickness on delayed images. Abscess walls ranged in thickness from 2 to 5 mm. Internal septations ranged in thickness from 2 to 3 mm. Abscess walls and septations were relatively uniform in thickness with no evidence of focal nodularity. Periabscess liver tissue was mildly hypointense on T1-weighted and mildly hyperintense on T2-weighted images in 20 lesions, which were either circumferential (n = 12) or wedge-shaped (n = 8). All these regions enhanced more than the remainder of the liver on immediate post-gadolinium images and remained relatively hyperintense on late phase images. Periabscess liver parenchyma was isointense on both T1- and T2-weighted images in 18 lesions, and in these lesions wedge-shaped subsegmental (n = 6) or segmental (n = 12) enhancement was observed on immediate gadolinium-enhanced images, which faded to isointensity on intermediate phase images. No perilesional signal changes and enhancement difference was observed in 15 lesions. Characteristic features of abscesses include: intense mural enhancement on early gadolinium-enhanced images, which persists with negligible change in thickness and intensity on later post-gadolinium images, and the presence of periabscess increased enhancement on immediate post-gadolinium images. These MRI features may help to distinguish abscesses from other focal liver lesions during differential diagnosis.