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

COVID-19 mRNA vaccine-related myocarditis: A PRISMA systematic review, imaging approach and differential diagnoses

We present a case involving a young individual who developed acute myocarditis on the fourth day following administration of a COVID-19 mRNA vaccine. The patient's condition was managed conservatively, resulting in a favorable outcome. This paper extensively discusses the pathogenesis, clinical manifestations, imaging characteristics of COVID-19 mRNA vaccine-related myocarditis and includes a comprehensive review of pertinent literature. Additionally, a systematic review of COVID-19 mRNA vaccine-related myocarditis, conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) principles, is presented. Healthcare professionals should maintain a clinical suspicion for COVID-19 mRNA vaccine-related myocarditis when encountering patients with confirmed myocarditis who have received recent COVID-19 mRNA vaccination, after ruling out other potential causes. The diagnosis of acute myocarditis primarily relies on adherence to the Lake Louise Criteria (LLC) for cardiac magnetic resonance (CMR). Nevertheless, specific CMR features or distinctive patterns indicative of COVID-19 mRNA vaccine-related myocarditis are currently undefined. Among patients with vaccine-related myocarditis, common CMR findings encompass subepicardial late gadolinium enhancement and T2-based myocardial edema, although these findings lack specificity and may resemble other medical conditions. Supportive care involving a short-term regimen of NSAIDs, colchicine, and steroids represents the cornerstone of treatment for this variant of myocarditis, which tends to be self-limiting with favorable short-term prognoses. Timely diagnosis is paramount for optimizing patient care.

Cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) imaging in the diagnosis and follow-up of patients with acute myocarditis and chronic inflammatory cardiomyopathy : A review paper with practical recommendations on behalf of the European Society of Cardiovascular Radiology (ESCR)

Advanced cardiac imaging techniques such as cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) are widely used in clinical practice in patients with acute myocarditis and chronic inflammatory cardiomyopathies (I-CMP). We aimed to provide a review article with practical recommendations from the European Society of Cardiovascular Radiology (ESCR), in order to guide physicians in the use and interpretation of CMR and PET in clinical practice both for acute myocarditis and follow-up in chronic forms of I-CMP.

The association of myocardial strain with cardiac magnetic resonance and clinical outcomes in patients with acute myocarditis

Introduction

The role of myocardial strain in risk prediction for acute myocarditis (AMC) patients, measured by cardiac magnetic resonance (CMR), deserves further investigation. Our objective was to evaluate the association between myocardial strain measured by CMR and clinical events in AMC patients.

Material and methods

This was a prospective single-center study of patients with AMC. We included 100 patients with AMC with CMR confirmation. The primary outcome was the composite of all-cause mortality, heart failure and AMC recurrence in 24 months. A subgroup analysis was performed on a sample of 36 patients who underwent a second CMR between 6 and 18 months. The association between strain measures and clinical events or an increase in left ventricular ejection fraction (LVEF) was explored using Cox regression analysis. Global peak radial, circumferential and longitudinal strain in the left and right ventricles was assessed. ROC curve analysis was performed to identify cutoff points for clinical event prediction.

Results

The mean follow-up was 18.7 ± 2.3 months, and the composite primary outcome occurred in 26 patients. The median LVEF at CMR at baseline was 57.5% (14.6%). LV radial strain (HR = 0.918, 95% CI: 0.858-0.982, p = 0.012), LV circumferential strain (HR = 1.177, 95% CI: 1.046-1.325, p = 0.007) and LV longitudinal strain (HR = 1.173, 95% CI: 1.031-1.334, p = 0.015) were independently associated with clinical event occurrence. The areas under the ROC curve for clinical event prediction were 0.80, 0.79 and 0.80 for LV radial, circumferential, and longitudinal strain, respectively. LV longitudinal strain was independently correlated with prognosis (HR = 1.282, CI 95%: 1.022-1.524, p = 0.007), even when analyzed together with ejection fraction and delayed enhancement. LV and right ventricle (RV) strain were not associated with an increase in LVEF. Finally, when the initial CMR findings were compared with the follow-up CMR findings, improvements in the measures of LV and RV myocardial strain were observed.

Conclusion

Measurement of myocardial strain by CMR can provide prognostic information on AMC patients. LV radial, circumferential and longitudinal strain were associated with long-term clinical events in these patients.

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.

Quantitative Assessment of Late Gadolinium Enhancement and Edema at Cardiac Magnetic Resonance in Low-Risk Myocarditis Patients

In this study, we aimed to quantify LGE and edema at short-tau inversion recovery sequences on cardiac magnetic resonance (CMR) in patients with myocarditis. We retrospectively evaluated CMR examinations performed during the acute phase and at follow-up. Forty-seven patients were eligible for retrospective LGE assessment, and, among them, twenty-five patients were eligible for edema evaluation. Both groups were paired with age- and sex-matched controls. The median left ventricle LGE was 6.4% (interquartile range 5.0−9.2%) at the acute phase, 4.4% (3.3−7.2%) at follow-up, and 4.3% (3.0−5.3%) in controls, the acute phase being higher than both follow-up and controls (p < 0.001 for both), while follow-up and controls did not differ (p = 0.139). An optimal threshold of 5.0% was obtained for LGE with 87% sensitivity and 48% specificity; the positive likelihood ratio (LR) was 1.67, and the negative LR was 0.27. Edema was 12.8% (9.4−18.1%) at the acute phase, 7.3% (5.5−8.8%) at follow-up, and 6.7% (5.6−8.6%) in controls, the acute phase being higher than both follow-up and controls (both p < 0.001), while follow-up and controls did not differ (p = 0.900). An optimal threshold of 9.5% was obtained for edema with a sensitivity of 76% and a specificity of 88%; the positive LR was 6.33, and the negative LR was 0.27. LGE and edema thresholds are useful in cases of suspected mild myocarditis.

More than 50% of Persistent Myocardial Scarring at One Year in "Infarct-like" Acute Myocarditis Evaluated by CMR

BACKGROUND

Cardiac magnetic resonance (CMR) has emerged as a reference tool for the non-invasive diagnosis of myocarditis. However, its role in follow-up (FU) after the acute event is unclear. The objectives were to assess the evolution of CMR parameters between the acute phase of infarct-like myocarditis and 12 months thereafter and to identify the predictive factors of persistent myocardial scarring at one year.

METHODS

All patients with infarct-like acute myocarditis confirmed by CMR were included. CMR was performed within 8 days following symptom onset, at 3 months and at one year. One-year FU included ECG, a cardiac stress test, Holter recording, biological assessments, medical history and a quality-of-life questionnaire. Patients were classified according to the presence or absence of complete recovery at one year based on the CMR evaluation.

RESULTS

A total of 174 patients were included, and 147 patients had three CMR. At one year, 79 patients (54%) exhibited persistent myocardial scarring on CMR. A multivariate analysis showed that high peak troponin at the acute phase (OR: 3.0-95%CI: 1.16-7.96-p = 0.024) and the initial extent of late gadolinium enhancement (LGE) (OR: 1.1-95%CI: 1.03-1.19-p = 0.006) were independent predictors of persistent myocardial scarring. Moreover, patients with myocardial scarring on the FU CMR were more likely to have premature ventricular contractions during the cardiac stress test (25% versus 9%, p = 0.008).

CONCLUSION

Less than 50% of patients with infarct-like acute myocarditis showed complete recovery at one year. Although major adverse cardiac events were rare, ventricular dysrhythmias at one year were more frequent in patients with persistent myocardial scarring.

[IRM et myocardite infectieuse]

Au cours des dix dernières années, l’IRM cardiaque est devenue un outil incontournable pour le diagnostic de myocardite aiguë. Elle peut, sous certaines conditions, permettre de surseoir à la coronarographie initiale dans de nombreuses situations. Son utilisation est préconisée en classe I, dans la situation du MINOCA, dans les recommandations de l’ESC de septembre 2020, pour permettre d’établir un diagnostic de certitude entre infarctus aigu, myocardite, Tako-Tsubo, ou autres cardiopathies en permettant d’améliorer la prise en charge thérapeutique et le suivi. Cet article reprend les principes techniques de l’IRM dans la myocardite (critères diagnostiques de Lake Louise et critères basés sur la cartographie tissulaire myocardique), les principaux diagnostics différentiels et la valeur pronostique, ainsi que la myocardite associée au COVID-19.

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.

Coronary artery disease (CAD) extension-derived risk stratification for asymptomatic diabetic patients: usefulness of low-dose coronary computed tomography angiography (CCTA) in detecting high-risk profile patients

BACKGROUND

As one of the most frequent risk factors for cardiovascular disease, type 2 diabetes mellitus (T2DM) is one of the largest causes of death. However, an acute cardiac presentation is not uncommon in diabetic patients, and the current investigative approach remains often inadequate. The aim of our study was to retrospectively stratify the risk of asymptomatic T2DM patients using low-dose 640-slice coronary computed tomography angiography (CCTA).

MATERIALS AND METHODS

CCTA examinations of 62 patients (mean age, 65 years) with previous diagnosis of type 2 diabetes and without cardiac symptoms were analyzed. Image acquisition was performed using a 640-slice CT. Per-patient, per-vessel and per-plaque analyses were performed. Stratification risk was evaluated according to the ESC guidelines. The patients were followed up after 2.21 ± 0.56 years from CCTA examination.

RESULTS

Coronary artery disease (CAD) was found in 58 patients (93.55%) presenting 290 plaques. Analysis of all samples showed severe-to-occlusive atherosclerosis in 24 patients (38.7% of cases). However, over the degree of stenosis, 23 patients were evaluated at high risk considering the extension of CAD. Good agreement was shown by the correlation of CAD extension/risk estimation and MACE incidence, according to a Kaplan-Meier survival analysis (p value = 0.001), with a 7.25-fold increased risk (HR 7.25 CI 2.13-24.7; p value = 0.002).

CONCLUSION

Our study confirms the high capability of CCTA to properly stratify the CV risk of asymptomatic T2DM patients. Its use could be recommended if we consider how current investigative strategies to correctly assess these patients often seem inadequate.

Cardiovascular Magnetic Resonance in Nonischemic Myocardial Inflammation: Expert Recommendations

This JACC Scientific Expert Panel provides consensus recommendations for an update of the cardiovascular magnetic resonance (CMR) diagnostic criteria for myocardial inflammation in patients with suspected acute or active myocardial inflammation (Lake Louise Criteria) that include options to use parametric mapping techniques. While each parameter may indicate myocardial inflammation, the authors propose that CMR provides strong evidence for myocardial inflammation, with increasing specificity, if the CMR scan demonstrates the combination of myocardial edema with other CMR markers of inflammatory myocardial injury. This is based on at least one T2-based criterion (global or regional increase of myocardial T2 relaxation time or an increased signal intensity in T2-weighted CMR images), with at least one T1-based criterion (increased myocardial T1, extracellular volume, or late gadolinium enhancement). While having both a positive T2-based marker and a T1-based marker will increase specificity for diagnosing acute myocardial inflammation, having only one (i.e., T2-based OR T1-based) marker may still support a diagnosis of acute myocardial inflammation in an appropriate clinical scenario, albeit with less specificity. The update is expected to improve the diagnostic accuracy of CMR further in detecting myocardial inflammation.

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.

Diagnostic Accuracy of Cardiovascular Magnetic Resonance in Acute Myocarditis: A Systematic Review and Meta-Analysis

OBJECTIVES

The purpose of this systematic review was to explore the diagnostic accuracy of various cardiovascular magnetic resonance (CMR) index tests for the diagnosis of acute myocarditis in adult patients.

BACKGROUND

Acute myocarditis remains one of the most challenging diagnoses in cardiology. CMR has emerged as the diagnostic tool of choice to detect acute myocardial injury and necrosis in patients with suspected myocarditis.

METHODS

We considered all diagnostic cohort and case-control studies. We searched MEDLINE, EMBASE, Cochrane Library, SCOPUS, and Web of Science up to April 21, 2017. We used the Quality Assessment of Diagnostic Accuracy Studies-2 tool to assess the quality of included studies. PROSPERO registration number CRD42017055778 was used.

RESULTS

Twenty-two studies were included in the systematic review. Because significant heterogeneity exists among the studies, we only present hierarchical receiver operator curves. The areas under the curve (AUC) for each index test were for T1 mapping 0.95 (95% confidence interval [CI]: 0.93 to 0.97), for T2 mapping 0.88 (95% CI: 0.85 to 0.91), for extracellular volume fraction (ECV) 0.81 (95% CI: 0.78 to 0.85), for increased T2 ratio/signal 0.80 (95% CI: 0.76 to 0.83), for late gadolinium enhancement (LGE) 0.87 (95% CI: 0.84 to 0.90), for early gadolinium enhancement (EGE) 0.78 (95% CI: 0.74 to 0.81), and for the Lake Louise criteria (LLC) 0.81 (95% CI: 0.77 to 0.84). Native T1 mapping had superior diagnostic accuracy across all index tests. The AUC of T2 mapping was greater than the AUC of increased T2 ratio/signal and EGE, whereas ECV showed no superiority compared with other index tests. LGE had better diagnostic accuracy compared with the classic CMR index tests, similar accuracy with T2 mapping and ECV, and only T1 mapping surpassed it.

CONCLUSIONS

Novel CMR mapping techniques provide high diagnostic accuracies for the diagnosis of acute myocarditis and constitute promising successors of the classic elements of the LLC for routine diagnostic protocols.