Lights and shadows of cardiac magnetic resonance imaging in acute myocarditis. Insights Imaging. 2016;7:99-110. [PMID: 26555392 PMCID: PMC4729715 DOI: 10.1007/s13244-015-0444-7]

Immunosuppressive therapy to treat newly diagnosed primary heart involvement in patients with systemic sclerosis: An Italian cardiac magnetic resonance based study

BACKGROUND

Primary heart involvement (pHI) is frequent in systemic sclerosis (SSc), and is associated with a poor prognosis. Therapeutic strategies to treat SSc-pHI are not yet defined.

OBJECTIVES

To evaluate the efficacy of immunosuppressive therapy on cardiac magnetic resonance (CMR) features in patients with CMR-proven SSc-pHI.

METHODS

The data from SSc patients with CMR-proven pHI who start or modify immunosuppressive therapy as indication for the newly diagnosed pHI and who had a follow-up CMR with parametric mapping after 6 to 18 months were analyzed. All patients underwent a comprehensive baseline evaluation of disease characteristics and organ involvement. In all patients, cardiac involvement was investigated at baseline and at follow up with CMR, evaluating: myocardial edema at STIR images, native-T1 and T2-mapping, extracellular volume fraction (ECV), and late gadoliunum enhancement (LGE). A p value <0.05 was considered as statistically significant.

RESULTS

Out of a cohort of 684 SSc patients, 35 (5.1 %) with SSc-pHI (females 77.1 %; median age 59 [46-64] years; anti-topoisomerase-I positivity 48.6 %; diffuse disease 34.3 %) were selected. In the majority of patients (74.3 %) at baseline CMR, signs of active myocardial inflammation (edema at STIR and/or increased T2-mapping) were found. Mycophenolate mofetil (MMF) was started in 15 (42.9 %) or increased in 7 (20.0 %) cases; 7 patients (20.0 %) received rituximab, 3 (8.6 %) azathioprine, while 3 patients were treated each one with cyclophosphamide (with pulse steroids), tocilizumab and hydroxychloroquine (with steroids). The median duration of immunosuppression was 12.0 [6.0-15.5] months. At follow-up CMR (performed after a median time 12.0 [6.5-16.0] months), increased T2-mapping suggestive for active myocardial inflammation was present in only 14 patients (40 %) (p = 0.003), and edema at STIR was present in 5 cases only (14.3 %) (p = 0.002). A significant reduction of T2-mapping (from 53.0 [49.0-55.0] to 51.0 [50.0-54.0] ms, p < 0.001), native-T1-mapping (from 1050.0 [1007.0-1084.0] to 1039.0 [1020.5-1080.5] ms, p = 0.022) and ECV (from 34.0 [31.0-36.75] to 33.0 [29.0-34.25] %, p = 0.041) was observed, especially in those with baseline increased mapping (T2-mapping from 53.0 [53.0-56.0] to 52.0 [50.0-57.0] ms; T1-mapping from 1066.0 [1050.0-1089.0] to 1057.0 [1027.5-1090.0] ms, p < 0.0001 for both]. The amelioration of the CMR features was paralleled by significant reduction of NT-proBNP (p = 0.008), high-sensitive troponin T (p = 0.003) and C-reactive protein (p = 0.010). No treatment-related adverse events were recorded.

CONCLUSIONS

Our data show that immunosuppression is a therapeutic strategy which has the potentiality to treat newly diagnosed SSc-pHI, by curbing signs of myocardial inflammation at CMR, and by significantly reducing cardiac enzymes, inflammatory markers and overall clinical burden. Larger prospective randomized studies are needed to confirm these data.

Comparison of diagnostic algorithms in clinically suspected viral myocarditis: Agreement between cardiovascular magnetic resonance, endomyocardial biopsy, and troponin T

AIMS

Myocardial inflammation is increasingly detected noninvasively by tissue mapping with cardiovascular magnetic resonance (CMR). Intraindividual agreement with endomyocardial biopsy (EMB) or markers of myocardial injury, high-sensitive cardiac troponin (hs-cTnT) in patients with clinically suspected viral myocarditis is incompletely understood.

METHODS

Prospective multicenter study of consecutive patients with clinically suspected myocarditis who underwent blood testing for hs-cTnT, CMR, and EMB as a part of diagnostic workup. EMB was considered positive based on immunohistological criteria in line with the European Society of Cardiology (ESC) definitions. CMR diagnoses employed tissue mapping using sequence-specific cut-off for native T1 and T2 mapping; active inflammation was defined as T1 ≥2 standard deviation (SD) and T2 ≥2 SD above the mean of normal range. Hs-cTnT of greater than 13.9 ng/L was considered significant.

RESULTS

A total of 114 patients (age (mean ± SD) 54 ± 16, 65% males) were included, of which 79 (69%) had positive EMB criteria, 64 (56%) CMR criteria, and a total of 58 (51%) positive troponin. Agreement between EMB and CMR diagnostic criteria was poor (CMR vs ESC: area under the curve (AUC): 0.51 (0.39-0.62)). The agreement between a significant hs-cTnT rise and CMR-based diagnosis of myocarditis was good (AUC: 0.84 (0.68-0.92); p < 0.001), but poor for EMB (0.50 (0.40-0.61). Hs-cTnT was significantly associated with native T1 and T2, high-sensitive C-reactive protein, and N-terminal pro-hormone brain natriuretic peptide (r = 0.37, r = 0.35, r = 0.30, r = 0.25; p < 0.001), but not immunohistochemical criteria or viral presence.

CONCLUSION

In clinically suspected viral myocarditis, all diagnostic approaches reflect the pathophysiological elements of myocardial inflammation; however, the differing underlying drivers only partially overlap. The EMB and CMR diagnostic algorithms are neither interchangeable in terms of interpretation of myocardial inflammation nor in their relationship with myocardial injury.

Myocarditis in anti-synthetase syndrome: clinical features and diagnostic modalities

OBJECTIVES

Myocarditis is an overlooked manifestation of anti-synthetase syndrome (ASS). Our study describes the clinical and instrumental features of ASS myocarditis and evaluates the performance of cardiac MRI (CMRI) with mapping techniques in assisting diagnosis of ASS myocarditis.

METHODS

Data from patients with ASS were retrospectively analysed. CMRI data for patients diagnosed with myocarditis, including late gadolinium enhancement (LGE), T2 ratio, T1 mapping, extracellular volume (ECV) and T2 mapping, were reviewed. Myocarditis was defined by the presence of symptoms and/or signs suggestive for heart involvement, including increased high-sensitive troponin T (hs-TnT) and/or N-terminal pro-brain natriuretic peptide (NT-proBNP), and at least an instrumental abnormality. The clinical features of patients with ASS with and without myocarditis were compared. A P-value of <0.05 was considered statistically significant.

RESULTS

Among a cohort of 43 patients with ASS [median age 58 (48.0-66.0) years; females 74.4%; anti-Jo1 53.5%], 13 (30%) were diagnosed with myocarditis. In 54% of those 13 patients, myocarditis was diagnosed at clinical onset. All patients with ASS with myocarditis had at least one CMRI abnormality: increased ECV in all cases, presence of LGE in 91%, and increased T1 and T2 mapping in 91%. The 2009 Lake Louise criteria (LLC) were satisfied by 6 patients, and the 2018 LLC by 10 patients. With the updated LLC, the sensitivity for myocarditis improved from 54.6% to 91.0%. Patients with ASS with myocarditis were more frequently males (53% vs 13%; P = 0.009) with fever (69% vs 17%; P = 0.001), and had higher hs-TnT [88.0 (23.55-311.5) vs 9.80 (5.0-23.0) ng/l; P < 0.001], NT-proBNP [525.5 (243.5-1575.25) vs 59.0 (32.0-165.5; P = 0.013) pg/ml; P = 0.013] and CRP [7.0 (1.7-15.75) vs 1.85 (0.5-2.86) mg/l; P = 0.011] compared with those without myocarditis.

CONCLUSION

In ASS, myocarditis is frequent, even at clinical onset. Patients with ASS with myocarditis frequently presented with fever and increased CRP, suggesting the existence of an inflammatory phenotype. The use of novel CMRI mapping techniques may increase diagnostic sensitivity for myocarditis in ASS.

Diagnosis and management of primary heart involvement in systemic sclerosis

PURPOSE OF REVIEW

In systemic sclerosis (SSc) primary heart involvement (pHI) is frequent, even though often unrecognized due to its occult nature and to the lack of a specific diagnostic algorithm. The purpose of this review is to report the state of the art of the evidence in the current literature, as well as the overall diagnostic modalities and therapeutic strategies for primary heart involvement in SSc.

RECENT FINDINGS

SSc-pHI is defined by the presence of cardiac abnormalities that are predominantly attributable to SSc rather than other causes and/or complications; it may be sub-clinical and must be confirmed through diagnostic investigations. Novel electrocardiographic analysis and cardiac magnetic resonance (CMR) with mapping techniques have been recently proposed, showing a great utility in the early identification of SSc-pHI and in the noninvasive characterization of myocardial tissue. Immunosuppressive therapy emerged as fundamental to curb myocardial inflammation, and recent preclinical and clinical data support the role of antifibrotic drugs to treat SSc-pHI.

SUMMARY

our review will help clinicians to properly integrate the available diagnostic modalities for the assessment of SSc-pHI. The ultimate goal is to propose a feasible diagnostic algorithm for the early identification of patients with SSc-pHI, and a schematic therapeutic approach to manage SSc-pHI.

Infarct-like versus Non-Infarct-like Clinical Presentation of Acute Myocarditis: Comparison of Cardiac Magnetic Resonance (CMR) Findings

BACKGROUND

The clinical presentation of acute myocarditis (AM) is widely variable, ranging from a subclinical disease to an infarct-like syndrome. Cardiac magnetic resonance (CMR) has become the reference non-invasive diagnostic tool for suspected AM, allowing the identification of the various hallmarks of myocardial inflammation (edema, fibrosis, and hyperemia). The aim of the study was to investigate any differences in morphological, functional, and tissue characterization CMR parameters between infarct-like AM in patients with unobstructed coronary arteries and non-infarct-like AM, diagnosed according to the original Lake-Louise Criteria (LLC); Methods: We retrospectively selected 39 patients diagnosed with AM according to LLC, divided into 2 groups according to the clinical presentation: infarct-like in group 1 patients and non-infarct-like in group 2 patients. CMR morphologic, functional, and tissue characterization parameters were analyzed and compared.

RESULTS

In group 1, CMR tissue characterization parameters were mainly altereda in septal location with mesocardial myocardial involvement; in group 2, CMR tissue characterization parameters were mainly altered in a lateral location with subepicardial myocardial involvement mainly at the mid-cavity. No significant differences in morphological or functional parameters were observed between the two study groups.

CONCLUSIONS

Our results showed differences in the localization and distribution of myocardial tissue damage assessed by CMR among forms of AM accompanied by an infarct-like clinical presentation compared with non-infarct-like presentations of AM. The mechanisms underlying the different preferential sites of damage observed in our study are not known, and we do not exclude the possibility of their prognostic implications.

Cardiac magnetic resonance of hypertrophic heart phenotype: A review

Hypertrophic heart phenotype is characterized by an abnormal left ventricular (LV) thickening. A hypertrophic phenotype can develop as adaptive response in many different conditions such as aortic stenosis, hypertension, athletic training, infiltrative heart muscle diseases, storage disorders and metabolic disorders. Hypertrophic cardiomyopathy (HCM) is the most frequent primary cardiomyopathy (CMP) and a genetical cause of cardiac hypertrophy. It requires the exclusion of any other cause of LV hypertrophy. Cardiac magnetic resonance (CMR) is a comprehensive imaging technique that allows a detailed evaluation of myocardial diseases. It provides reproducible measurements and myocardial tissue characterization. In clinical practice CMR is increasingly used to confirm the presence of ventricular hypertrophy, to detect the underlying cause of the phenotype and more recently as an efficient prognostic tool. This article aims to provide a detailed overview of the applications of CMR in the setting of hypertrophic heart phenotype and its role in the diagnostic workflow of such condition.

Radiomics analysis of short tau inversion recovery images in cardiac magnetic resonance for the prediction of late gadolinium enhancement in patients with acute myocarditis

RATIONALE AND OBJECTIVES

Cardiac Magnetic Resonance (CMR) imaging is recommended as the reference diagnostic non-invasive modality for myocarditis but is often limited by patients' compliance. The purpose of this study is to evaluate the validity of Radiomics applied to Short Tau Inversion Recovery (STIR) sequences, in predicting the presence of LGE in patients with suspected acute myocarditis.

MATERIALS AND METHODS

171 STIR images on short-axis view were segmented with "MaZda" software ver 4.6, by placing a region of interest (ROI) on the left ventricle by two radiologists in consensus. Images were classified according to the presence of LGE in the equivalent short-axis T1-IR slice. A total of 337 ROI features were extracted for each image. Dataset was then split into two parts (train and test set) with 70:30 ratio.

RESULTS

Eleven classification models were trained. An Ensemble Machine Learning (EML) model was obtained by averaging the predictions of models with accuracy on test set >70%. The EML documented accuracy of 0.75, sensitivity of 0.8 and a specificity of 0.73 with a NPV of 0.81 and a PPV of 0.7, with AUC of 0.79 (95% CI: 0.66-0.92).

CONCLUSION

Radiomics and machine learning analysis could be a promising approach in reducing scan times without reducing diagnostic accuracy in predicting LGE in patients with acute myocarditis.

Cardiac magnetic resonance in systemic sclerosis myocarditis: the value of T2 mapping to detect myocardial inflammation

Objectives

Myocarditis in systemic sclerosis (SSc) is associated with a poor prognosis. Cardiac Magnetic Resonance (CMR) is the non-invasive diagnostic modality of choice for SSc-myocarditis. Our study investigates the performance of the mapping techniques, included in the revised Lake Louise Criteria (LLC), for the identification of SSc-myocarditis.

Methods

CMR data (right and left ventricular function and morphology, early and late gadolinium enhancement [LGE], T2 ratio, and T1 mapping, extra-cellular volume [ECV] and T2 mapping) of SSc patients diagnosed with myocarditis were reviewed. Myocarditis was defined by the presence of symptoms of SSc-heart involvement with increased high-sensitive troponin T(hs-TnT) and/or NT-proBNP and at least an abnormality at 24 h-ECG-Holter and/or echocardiography and/or CMR. A p-value &lt; 0.05 was considered as statistically significant.

Results

19 patients (median age 54 [46–70] years; females 78.9%; diffuse SSc 52.6%; anti-Scl70 + 52.6%) were identified: 11(57.9%) had echocardiographic, and 8(42.8%) 24 h-ECG Holter abnormalities. All patients had at least one CMR abnormality: LGE in 18(94.7%), increased ECV in 10(52.6%), T2 mapping &gt; 50ms in 15(78.9%). Median T1 and T2 mapping were 1085[1069–1110]ms and 53.1[52–54]ms, respectively. T1 mapping directly correlated with NT-proBNP(r = 0.620; p= 0.005), ESR(r = 0.601; p= 0.008), CRP(r = 0.685; p= 0.001) and skin score(r = 0.507; p= 0.027); ECV correlated with NT-proBNP serum levels(r = 0.702; p= 0.001). No correlations emerged between T2 mapping and other parameters. Ten patients satisfied the 2009 LLC, 17 the 2018 LLC. With the new criteria including T2-mapping, the sensitivity improved from 52.6% to 89.5%.

Conclusion

the CMR mapping techniques improve the sensitivity to detect myocardial inflammation in patients with SSc-heart involvement. The evaluation of T2 mapping increases diagnostic accuracy for the recognition of myocardial inflammation in SSc.

Heart Involvement in Systemic Sclerosis: the Role of Magnetic Resonance Imaging

Systemic sclerosis (SSc) is a severe connective tissue disease characterized by diffuse vascular damage and aberrant activation of immune system, resulting in inflammation and fibrosis of skin and internal organs, including the heart. Cardiac involvement is frequent in SSc, even though often unrecognized due to the occult nature at early stages and to the lack of a defined diagnostic algorithm. Once clinically evident, heart involvement is associated with a poor prognosis, representing the leading cause of death in about one third of SSc patients. Thus, its early recognition and monitoring are of crucial importance to allow a prompt therapeutic intervention and to improve patients' outcomes. Cardiac Magnetic Resonance (CMR) is a non-invasive, non-radiating imaging technique of great importance for the assessment of cardiovascular system, and represents the modality of choice for the morpho-functional and structural characterization of the heart. In SSc, CMR allows a precise definition of biventricular and biatrial size and function, and a detailed tissue characterization. CMR has been therefore extensively proposed in SSc as a non-invasive diagnostic tool to characterize heart involvement, particularly myocardial involvement. In this review, we summarize the most recent evidences to support the use of CMR in SSc as an important tool to recognize and characterize scleroderma heart disease. Furthermore, the unmet needs and the future perspectives of a CMR-based approach for the early detection of SSc heart involvement are discussed.

Advanced cardiac imaging in athlete's heart: unravelling the grey zone between physiologic adaptation and pathology

Over the last decades, interest toward athlete's heart has progressively increased, leading to improve the knowledge on exercise-induced heart modifications. Sport may act as a trigger for life-threatening arrhythmias in patients with structural or electrical abnormalities, hence requiring to improve the diagnostic capability to differentiate physiological from pathological remodeling. Pathological alterations are often subtle at the initial stages; therefore, the challenge is to promptly identify athletes at risk of sudden cardiac death during the pre-participation screening protocols. Advanced imaging modalities such as coronary computed tomography angiography (CCTA) and cardiac magnetic resonance (CMR) can non-invasively depict coronary vessels and provide a deep morpho-functional and structural characterization of the myocardium, in order to rule out pathological life threatening alterations, which may overlap with athletes' heart remodeling. The purpose of the present narrative review is to provide an overview of most frequent diagnostic challenges, defining the boundaries between athlete's heart remodeling and pathological structural alteration with a focus on the role and importance of CCTA and CMR.

Machine learning and network medicine: a novel approach for precision medicine and personalized therapy in cardiomyopathies

The early identification of pathogenic mechanisms is essential to predict the incidence and progression of cardiomyopathies and to plan appropriate preventive interventions. Noninvasive cardiac imaging such as cardiac computed tomography, cardiac magnetic resonance, and nuclear imaging plays an important role in diagnosis and management of cardiomyopathies and provides useful prognostic information. Most molecular factors exert their functions by interacting with other cellular components, thus many diseases reflect perturbations of intracellular networks. Indeed, complex diseases and traits such as cardiomyopathies are caused by perturbations of biological networks. The network medicine approach, by integrating systems biology, aims to identify pathological interacting genes and proteins, revolutionizing the way to know cardiomyopathies and shifting the understanding of their pathogenic phenomena from a reductionist to a holistic approach. In addition, artificial intelligence tools, applied to morphological and functional imaging, could allow imaging scans to be automatically analyzed to extract new parameters and features for cardiomyopathy evaluation. The aim of this review is to discuss the tools of network medicine in cardiomyopathies that could reveal new candidate genes and artificial intelligence imaging-based features with the aim to translate into clinical practice as diagnostic, prognostic, and predictive biomarkers and shed new light on the clinical setting of cardiomyopathies. The integration and elaboration of clinical habits, molecular big data, and imaging into machine learning models could provide better disease phenotyping, outcome prediction, and novel drug targets, thus opening a new scenario for the implementation of precision medicine for cardiomyopathies.

Use of the new Lake Louise Criteria improves CMR detection of atypical forms of acute myocarditis

The purpose of our study was to compare diagnostic performance of old and new Lake Louise Criteria (oLLC and nLLC) among different clinical presentations: infarct-like (IL), cardiomyopathic (CM) and arrhythmic (AR). 102 patients with clinical suspicion of acute myocarditis underwent cardiac magnetic resonance (CMR) on a 1.5 T scanner. Protocol included cine-SSFP, T2-weighted STIR, T2 mapping, early and late gadolinium enhancement and T1 mapping acquired before and after gadolinium administration. The degree of agreement has been calculated with Cohen's K test. 42 patients also underwent endomyocardial biopsy (EMB). IL onset was present in 54/102 patients, CM in 28/102 and AR in 20/102. nLLC were positive in 58.3% of the patients, while oLLC in 37.9%, k = 0.57 (IC: 0.428-0.713). The degree of agreement between nLLC and oLLC was 0.49 (IC: 0.111-0.876) for AR onset (nLLC positive in 35% vs oLLC in 15%), 0.25 (IC: 0.035-0.459) for CM pattern (nLLC positive in 60.7% vs oLLC 17.9%) and 0.73 (IC: 0.543-0.912) for IL presentation (nLLC positive in 66.7% vs oLLC in 57.4%). Diagnostic accuracy was 75% for both nLLC and oLLC among IL onset, and 41.6% for oLLC vs 66.7% for nLLC, as regards CM clinical presentation. nLLC have improved diagnostic performance of CMR for the diagnosis of acute myocarditis, in particular for atypical clinical presentation.

The perpetual sword of Damocles: Cardiac involvement in systemic sclerosis and the role of non-invasive imaging modalities in medical decision making

Cardiac involvement in systemic sclerosis (SSc-CI) may be either primary or secondary to pathologic processes in other organs. In contrast to other autoimmune rheumatic diseases, primary SSc-CI preferentially manifests as non-ischemic myocardial fibrosis, with or without myocardial inflammation and minimal involvement of epicardial coronary arteries. Recent developments in cardiovascular (CV) imaging modalities and their increasing availability necessitate the creation of concrete recommendations for use in SSc patients, based on the most recent scientific evidence. Echocardiography offers rapid, effective, multiparametric, and widely available imaging evaluation of SSc patients, owing to its ability to analyze both left and right chambers, as well as pulmonary hemodynamics. However, it is an operator- and acoustic window-dependent modality that cannot perform tissue characterization, which is crucial in these conditions. CV magnetic resonance in SSc patients can accurately evaluate biventricular volumes, ejection fractions, myocardial fibrosis load, and changes suggestive of myocarditis. T2 mapping is the best index of edema indicating acute myocardial inflammation, while late gadolinium enhancement is an index of replacement fibrosis. Extracellular volume fraction (ECV) is an indicator of diffuse myocardial fibrosis only in the absence of significant myocardial inflammation. However, if myocardial inflammation/fibrosis coexist, ECV reflects a combination of the two, but it cannot completely discriminate between them. SSc-CI hangs like the sword of Damocles over physicians managing SSc patients. A constructive partnership between the rheumatologist and the cardiologist is necessary to provide each SSc patient with a comprehensive screening protocol for early detection and treatment of cardiopulmonary pathologic processes.

Cardiovascular magnetic resonance in myocardial infarction with non-obstructive coronary arteries patients: A review

The diagnosis of myocardial infarction with non-obstructive coronary arteries (MINOCA) necessitates documentation of an acute myocardial infarction (AMI), non-obstructive coronary arteries, using invasive coronary angiography or coronary computed tomography angiography and no clinically overt cause for AMI. Historically patients with MINOCA represent a clinical dilemma with subsequent uncertain clinical management. Differential diagnosis is crucial to choose the best therapeutic option for ischemic and non-ischemic MINOCA patients. Cardiovascular magnetic resonance (CMR) is able to analyze cardiac structure and function simultaneously and provides tissue characterization. Moreover, CMR could identify the cause of MINOCA in nearly two-third of patients providing valuable information for clinical decision making. Finally, it allows stratification of patients with worse outcomes which resulted in therapeutic changes in almost half of the patients. In this review we discuss the features of CMR in MINOCA; from exam protocols to imaging findings.

Early T1 Myocardial MRI Mapping: Value in Detecting Myocardial Hyperemia in Acute Myocarditis

Background Hyperemia is a key component of acute myocarditis (AM). Early gadolinium uptake because of myocardial hyperemia may be quantified by using T1 mapping. Purpose To evaluate the value of early enhanced T1 shortening for the diagnosis of acute myocarditis. Materials and Methods Study participants suspected of having AM and healthy control (HC) participants were prospectively enrolled from September 2016 to May 2019. Participants underwent 1.5-T cardiac MRI including Lake Louise criteria, T2 mapping, native T1, and extracellular volume, with the addition of early enhanced T1 mapping (2 minutes after intravenous administration of 0.15 mmol/kg gadobutrol). Color-coded maps of the percentage of T1 shortening from precontrast to early postcontrast were generated. Optimal early T1 shortening cut-off value and its diagnostic performance in the identification of acute myocarditis were calculated. Results Forty-five study participants with AM (median age, 40 years; interquartile range [IQR], 20-46 years; 22 women) diagnosed according to multidisciplinary clinical evaluation, electrocardiography, laboratory test, echocardiography, cardiac MRI, and coronary CT and/or invasive angiography. Findings were confirmed by endomyocardial biopsy in 64% (29 of 45) of participants. MRI parameters were compared with 19 HC participants (median age, 39 years; IQR, 28-46 years; seven women). Median early T1 shortening was 75% (IQR, 72%-78%) in participants with AM versus 65% (IQR, 61%-66%) in HC participants (P < .001). Early T1 shortening showed high diagnostic performance (area under the receiver operating characteristic curve [AUC], 0.97; 95% confidence interval [CI]: 0.94, 1.00) and excellent interobserver reproducibility (intraclass correlation coefficient: 0.98; 95% CI: 0.96, 1.00). Early T1 shortening of 70% or greater identified acute myocarditis with 93% sensitivity, 100% specificity, and 95% diagnostic accuracy. Early T1 shortening had better diagnostic performance than late percentage T1 shortening (AUC, 0.97 vs 0.90, respectively; P = .03) and extracellular volume (AUC, 0.97 vs 0.88, respectively; P = .046), and similar to native T1 (AUC, 0.97 vs 0.93, respectively; P = .63) and T2 mapping (AUC, 0.97 vs 0.97, respectively; P > .99). Conclusion In this proof-of-concept study, percentage of T1 shortening at early enhanced T1 mapping showed high accuracy for the diagnosis of acute myocarditis. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by De Cecco and Monti in this issue.

Association of segmental T2 ratio and late gadolinium enhancement in patients with acute myocarditis: a feasibility study

BACKGROUND

Cardiac magnetic resonance is a valuable tool in the diagnosis of acute myocarditis, but dyspnea or chest pain often reduce patient's compliance, so definition of faster magnetic resonance protocols is of paramount importance.

METHODS

Short tau inversion recovery (STIR) and phase sensitive inversion recovery images for the assessment of late gadolinium enhancement (LGE)of 22 patients with clinical suspicion of acute myocarditis were retrospectively evaluated. Signal intensity in STIR images was measured by 2 readers by placing region of interests (ROIs) within the area of maximal signal intensity in each myocardial segment derived from the ACC/AHA segmental scheme. Segmental T2 ratio was assessed with the formula: signal intensity of myocardium/signal intensity of muscle. Receiver operating characteristic (ROC) curves were used to compare diagnostic performance of T2 Signal intensity and T2 ratio in predicting the presence of LGE in each myocardial segment. Bland-Altman analysis was used to assess inter reader agreement.

RESULTS

Signal intensity in STIR images showed an area under the curve (AUC) of 0.54 (95% CI: 0.44-0.63) for reader 1 and 0.53(95% CI: 0.44-0.63) for reader 2. Segmental T2 ratio showed an AUC of 0.8 (95% CI: 0.73-0.87) for reader 1 and 0.77 (95% CI: 0.71-0.84) for reader 2. Bland-Altman analysis showed good agreement for both T2 signal intensity (mean difference =-18.5 reader1 vs. reader 2 and 2SD=247.3) and T2 ratio (mean difference=0.03 vs. reader2 and 2SD=0.9).

CONCLUSIONS

Segmental T2 ratio showed a good diagnostic accuracy in predicting the presence of LGE in patients with clinical suspicion of acute myocarditis and might be a promising approach in reducing scan times with no reduction in diagnostic accuracy.

Aortic valvular imaging with cardiovascular magnetic resonance: seeking for comprehensiveness

Cardiovascular magnetic resonance (CMR) has an emerging role in aortic valve disease evaluation, becoming an all-in-one technique. CMR evaluation of the anatomy and flow through the aortic valve has a higher reproducibility than echocardiography. Its unique ability of in vivo myocardial tissue characterization, significantly improves the risk stratification and management of patients. In addition, CMR is equivalent to cardiac CT angiography for trans-aortic valvular implantation and surgical aortic valve replacement planning; on the other hand, its role in the evaluation of ventricular function improving and post-treatment complications is undisputed. This review encompasses the existing literature regarding the role of CMR in aortic valve disease, exploring all the aspects of the disease, from diagnosis to prognosis.

Assessment of acute myocarditis by cardiac magnetic resonance imaging: Comparison of qualitative and quantitative analysis methods

BACKGROUND

To compare cardiac magnetic resonance (CMR) qualitative and quantitative analysis methods for the noninvasive assessment of myocardial inflammation in patients with suspected acute myocarditis (AM).

METHODS

A total of 61 patients with suspected AM underwent coronary angiography and CMR. Qualitative analysis was performed applying Lake-Louise Criteria (LLC), followed by quantitative analysis based on the evaluation of edema ratio (ER) and global relative enhancement (RE). Diagnostic performance was assessed for each method by measuring the area under the curves (AUC) of the receiver operating characteristic analyses. The final diagnosis of AM was based on symptoms and signs suggestive of cardiac disease, evidence of myocardial injury as defined by electrocardiogram changes, elevated troponin I, exclusion of coronary artery disease by coronary angiography, and clinical and echocardiographic follow-up at 3 months after admission to the chest pain unit.

RESULTS

In all patients, coronary angiography did not show significant coronary artery stenosis. Troponin I levels and creatine kinase were higher in patients with AM compared to those without (both P < .001). There were no significant differences among LLC, T2-weighted short inversion time inversion recovery (STIR) sequences, early (EGE), and late (LGE) gadolinium-enhancement sequences for diagnosis of AM. The AUC for qualitative (T2-weighted STIR 0.92, EGE 0.87 and LGE 0.88) and quantitative (ER 0.89 and global RE 0.80) analyses were also similar.

CONCLUSIONS

Qualitative and quantitative CMR analysis methods show similar diagnostic accuracy for the diagnosis of AM. These findings suggest that a simplified approach using a shortened CMR protocol including only T2-weighted STIR sequences might be useful to rule out AM in patients with acute coronary syndrome and normal coronary angiography.

Two-dimensional and three-dimensional cardiac magnetic resonance feature-tracking myocardial strain analysis in acute myocarditis patients with preserved ejection fraction

To explore the potential role of two- (2D) and three-dimensional (3D) cardiac magnetic resonance (CMR) feature tracking (FT) myocardial strain analysis in identifying sub-clinical myocardial systolic and diastolic dysfunction in acute myocarditis patients with preserved ejection fraction (EF). Prospective two centre study-control study. Thirty patients (9 female, 37.2 ± 11.8 years.) with a CMR diagnosis of acute myocarditis according to the Lake Louise Criteria and preserved EF (≥ 55%) were included in the analysis. CMR data from 24 healthy volunteers (11 female, 36.2 ± 12.5 years.) served as control. 2D and 3D LV tissue tracking analysis were performed in a random fashion by two double-blinded operators. Variables were checked for normality and analysed with parametric test. The baseline characteristics of myocarditis patients with preserved EF and the healthy volunteers were perfectly comparable, except for the LV mass index and T1 and T2 mapping values (p < 0.001). The results of the interobserver variability in the 2D and 3D LV CMR FT myocardial strain analysis were p > 0.42, ICC > 0.80 and η² > 0.98. There was no statistical difference in 2D and 3D global radial, circumferential and longitudinal strain peak (%) and both systolic and diastolic strain rate (1/s) between acute myocarditis with preserved EF and healthy volunteers (all p = ns). There were no difference in 2D and 3D global radial, circumferential and longitudinal strain peak and both systolic and diastolic strain rate of the LV between acute myocarditis patients with preserved ejection fraction and healthy volunteers.

Oedema-fibrosis in Duchenne Muscular Dystrophy: Role of cardiovascular magnetic resonance imaging

Duchenne muscular dystrophy (DMD) is an X-linked muscle disorder characterized by progressive, irreversible loss of cardiac and skeletal muscular function. Muscular enlargement in DMD is attributed to oedema, due to the increased cytoplasmic Na+ concentration. The aim of this review was to present the current experience and emphasize the role of cardiovascular magnetic resonance (CMR) in the diagnosis of this condition. DMD patients' survival depends on ventilatory assistance, as respiratory muscle dysfunction was the most common cause of death in the past. Currently, due to improved ventilatory assistance, cardiomyopathy has become the main cause of death, even though clinically overt heart failure may be absent. CMR is the technique of choice to assess the pathophysiologic phenomena taking place in DMD, such as myocardial oedema and subepicardial fibrosis. The classic index to assess oedema is the T2-weighted short-tau inversion recovery (T2w-STIR), as it suppresses the signal from flowing blood and resident fat and enhances sensitivity to tissue fluid. Furthermore, CMR is the most reliable technique to detect and quantify fibrosis in DMD. Recently, the new indices T2, T1 mapping (native and postcontrast) and the extracellular volume (ECV) allow a more accurate approach of myocardial oedema and fibrosis. To conclude, the assessment of cardiac oedema and subepicardial fibrosis in the inferolateral wall of the left heart ventricle are the most important early finding in DMD with preserved ventricular function, and CMR, using both the classic and the new indices, is the best technique to detect and monitor these lesions.

Clinical and magnetic resonance evolution of "infarct-like" myocarditis

AIMS

To analyse the clinical and magnetic resonance evolution of myocarditis in patients with an "infarct-like" presentation pattern.

METHODS

The study is a retrospective analysis of 52 patients with clinical diagnosis of "infarct-like" myocarditis confirmed by CMR as acute myocarditis according to Lake Louise criteria and 6 months follow-up. The CMR protocol included T2-weighted (oedema), early (hyperaemia) and late (fibrosis/necrosis) gadolinium enhancement sequences, according to Lake Louise criteria. Clinical and radiological follow-up by CMR was performed after a median time interval of 6 months (interquartile range 5-8). Quantitative outcomes were checked for normality and compared with the non-parametric Wilcoxon's test for matched data.

RESULTS

At the clinical follow-up all patients were free of symptoms and reported no cardiac complications. The CMR follow-up evidenced a significant increase of the ejection fraction (from 53 ± 6 to 55 ± 4%, p = 0.03), a decrease of the ventricular mass [from 67.0 (58.8-79.0) to 61.0 (54.0-67.0), p < 0.0001] without significant modification of the cardiac volume index (p = 0.26). No patient had residual oedema or capillary leakage: the T2 ratio decreased from 3.94 (3.00-4.86) to 0.98 (0.75-1.17) with p < 0.0001 and the Early gadolinium enhancement (EGE) ratio from 5.7 (4.8-6.5) to 2.9 (2.4-3.2) with p < 0.0001. Late gadolinium enhancement (LGE) persisted over the course of the follow-up in 48/52 patients, but with a significant reduction in every patient (LGE % from 34.3 ± 9.1 to 19.4 ± 6.6%; p < 0.0001).

CONCLUSION

Patients diagnosed with "infarct-like" myocarditis, according to both clinical and CMR examinations may look forward to a positive evolution with a good prognosis.