Infarct-like Myocarditis Research Articles

Cardiac MRI in infarct-like myocarditis: transmural extension of late gadolinium enhancement is associated with worse outcomes

ObjectivesTo assess the prognostic value of cardiac MRI (CMR) parameters for the occurrence of major adverse cardiac events (MACE) in patients with infarct-like myocarditis.MethodsIn this retrospective single-center study, patients with CMR-confirmed acute myocarditis with infarct-like presentation were identified (2007–2020). Functional and structural parameters were analyzed including late gadolinium enhancement (LGE). The primary endpoint was the occurrence of MACE up to 5 years after discharge.ResultsIn total, 130 patients (mean age, 40 ± 19 years; 97 men, 75%) with infarct-like myocarditis were included. CMR was conducted a median of 3 days (interquartile range [IQR], 1–5) after symptom onset. MACE occurred in 18/130 patients (14%) during a median follow-up of 19.3 months (IQR, 4.5–53). The median extent of LGE was 7% (IQR, 4–10). LGE affected the subepicardium in 111/130 patients (85%), the midwall in 45/130 patients (35%), and both the subepicardium and midwall in 27/130 patients (21%). Transmural extension of non-ischemic LGE lesions was observed in 15/130 patients (12%) and septal LGE in 42/130 patients (32%). In univariable Cox regression analysis, a significant association was found between the occurrence of MACE and both, quantified LGE extent and transmural LGE pattern. In multivariable analysis, transmural extension of LGE was an independent predictor for MACE (hazard ratio, 6.34; 95% confidence interval: 2.29–17.49; p < 0.001). Patients with the transmural extension of LGE had a shorter event-free time on Kaplan–Meier analysis (log-rank p < 0.001).ConclusionsMACE occurred in 14% of patients with infarct-like myocarditis during follow-up. A transmural extension of non-ischemic LGE was associated with a worse long-term prognosis.Critical relevance statementCMR-based assessment of transmural extension of non-ischemic LGE holds the potential to serve as an easily assessable marker for risk stratification in patients with infarct-like myocarditis.Key PointsThe prognostic value of CMR was studied in patients with infarct-like myocarditis.The extent of LGE and transmural extension were linked to adverse cardiac events.Transmural non-ischemic LGE can serve as an easily assessable prognostic marker.Graphical

Serum Concentrations of Matrix Metalloproteinase-1 and Procollagen Type I Carboxy Terminal Propeptide Discriminate Infarct-Like Myocarditis and Non-ST-Segment-Elevation Myocardial Infarction.

Biomarkers simplifying the diagnostic workup by discriminating between non-ST-segment-elevation myocardial infarction (NSTEMI) and infarct-like myocarditis are an unmet clinical need. A total of 105 subjects were categorized into groups as follows: ST-segment-elevation myocardial infarction (n=36), NSTEMI (n=22), infarct-like myocarditis (n=19), cardiomyopathy-like myocarditis (n=18), and healthy control (n=10). All subjects underwent cardiac magnetic resonance imaging, and serum concentrations of matrix metalloproteinase-1 (MMP-1) and procollagen type I carboxy terminal propeptide (PICP) were measured. Biomarker concentrations in subjects presenting with acute coronary syndrome and non-ST-segment-elevation, for example NSTEMI or infarct-like myocarditis, categorized as the non-ST-segment-elevation acute coronary syndrome-like cohort, were of particular interest for this study. Compared with healthy controls, subjects with myocarditis had higher serum concentrations of MMP-1 and PICP, while no difference was observed in individuals with myocardial infarction. In the non-ST-segment-elevation acute coronary syndrome-like cohort, MMP-1 concentrations discriminated infarct-like myocarditis and NSTEMI with an area under the receiver operating characteristiccurve (AUC) of 0.95 (95% CI, 0.89-1.00), whereas high-sensitivity cardiac troponin Tperformed inferiorly (AUC, 0.74 [95% CI, 0.58-0.90]; P=0.012). Application of an optimal MMP-1 cutoff had 94.4% sensitivity (95% CI, 72.7%-99.9%) and 90.9% specificity (95% CI, 70.8%-98.9%) for the diagnosis of infarct-like myocarditis in this cohort. The AUC of PICP in this context was 0.82 (95% CI, 0.68-0.97). As assessed by likelihood ratio tests, incorporating MMP-1 or PICP with age and C-reactive protein into composite prediction models enhanced their diagnostic performance. MMP-1 and PICP could potentially be useful biomarkers for differentiating between NSTEMI and infarct-like myocarditis in individuals with non-ST-segment-elevation acute coronary syndrome-like presentation, though further research is needed to validate their clinical applicability.

Differentiation of acute non-ST elevation myocardial infarction and acute infarct-like myocarditis by visual pattern analysis: a head-to-head comparison of different cardiac MR techniques

ObjectivesParametric cardiac magnetic resonance (CMR) techniques have improved the diagnosis of pathologies. However, the primary tool for differentiating non-ST elevation myocardial infarction (NSTEMI) from myocarditis is still a visual assessment of conventional signal-intensity-based images. This study aimed at analyzing the ability of parametric compared to conventional techniques to visually differentiate ischemic from non-ischemic myocardial injury patterns.MethodsTwenty NSTEMI patients, twenty infarct-like myocarditis patients, and twenty controls were examined using cine, T2-weighted CMR (T2w) and late gadolinium enhancement (LGE) imaging and T1/T2 mapping on a 1.5 T scanner. CMR images were presented in random order to two experienced fully blinded observers, who had to assign them to three categories by a visual analysis: NSTEMI, myocarditis, or healthy.ResultsThe conventional approach (cine, T2w and LGE combined) had the best diagnostic accuracy with 92% (95%CI: 81–97) for NSTEMI and 86% (95%CI: 71–94) for myocarditis. The diagnostic accuracies using T1 maps were 88% (95%CI: 74–95) and 80% (95%CI: 62–91), 84% (95%CI: 67–93) and 74% (95%CI: 54–87) for LGE, and 83% (95%CI: 66–92) and 73% (95%CI: 53–87) for T2w. The accuracies for cine (72% (95%CI: 52–86) and 60% (95%CI: 38–78)) and T2 maps (62% (95%CI: 40–79) and 47% (95%CI: 28–68)) were significantly lower compared to the conventional approach (p < 0.001 and p < 0.0001).ConclusionsThe conventional approach provided a reliable visual discrimination between NSTEMI, myocarditis, and controls. The diagnostic accuracy of a visual pattern analysis of T1 maps was not significantly inferior, whereas the diagnostic accuracy of T2 maps was not sufficient in this context.Clinical relevance statementThe ability of parametric compared to conventional CMR techniques to visually differentiate ischemic from non-ischemic myocardial injury patterns can avoid potentially unnecessary invasive coronary angiography and help to shorten CMR protocols and to reduce the need of gadolinium contrast agents.Key Points•A visual differentiation of ischemic from non-ischemic patterns of myocardial injury is reliably achieved by a combination of conventional CMR techniques (cine, T2-weighted and LGE imaging).•There is no significant difference in accuracies between visual pattern analysis on native T1 maps without providing quantitative values and a conventional combined approach for differentiating non-ST elevation myocardial infarction, infarct-like myocarditis, and controls.•T2 maps do not provide a sufficient diagnostic accuracy for visual pattern analysis for differentiating non-ST elevation myocardial infarction, infarct-like myocarditis, and controls.

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.

Assessment of Coronary Inflammation by Pericoronary Fat Attenuation Index in Clinically Suspected Myocarditis with Infarct-Like Presentation

Background: The pathophysiology of angina-like symptoms in myocarditis is still unclear. Perivascular fat attenuation index (pFAI) by coronary computed tomography angiography (CCTA) is a non-invasive marker of coronary inflammation (CI) in atherosclerosis. We explored the presence of CI in clinically suspected myocarditis with infarct-like presentation. Methods: We retrospectively included 15 consecutive patients (67% male, age 30 ± 10 years) with clinically suspected infarct-like myocarditis who underwent CCTA to rule out coronary artery disease. Right coronary artery (RCA) pFAI mean value was compared with that of healthy volunteers. Results: Mean RCA pFAI value was −92.8 ± 8.4 HU, similar to that of healthy volunteers (−95.2 ± 6.0, p = 0.8). We found no correlation between RCA pFAI mean values and peak Troponin I (r = −0.43, p = 0.11) and C-reactive protein at diagnosis (r = −0.25, p = 0.42). Patients with higher pFAI values showed higher biventricular end-systolic volumes (ESV) (p = 0.038 for left and p = 0.024 for right ventricle) and lower right ventricular ejection fraction (RVEF) (p = 0.038) on cardiovascular magnetic resonance. Conclusions: In clinically suspected myocarditis with infarct-like presentation, RCA pFAI values are lower than those validated in atherosclerosis. The correlation between higher pFAI values, higher biventricular ESV and lower RVEF, may suggest a role of pFAI in predicting non-atherosclerotic CI (i.e., infective/immune-mediated “endothelialitis”).

More than 50% of non-healing at one year in “infarct-like” acute myocarditis evaluated by cardiac magnetic resonance

Cardiac magnetic resonance (CMR) has emerged as a reference for the non-invasive diagnosis of myocarditis, but its role in follow-up (FU) after the acute event is unknown. The objectives of our study were to assess the evolution of CMR parameters at 12 months after infarct-like myocarditis. All patients with acute myocarditis confirmed by CMR [i.e. typical non-ischemic late gadolinium enhancement (LGE)] were prospectively included from 2012 to 2018 at Dijon University Hospital. CMR was performed < 7 days following symptom onset, at 3 months and 1 year after the acute event. FU included ECG, cardiac stress test, Holter recording, biological assessments, medical history and a QoL questionnaire. Patients were classified according to complete healing at CMR. In total, 111 patients were included. At one year, 59 patients (53%) exhibited persistent myocarditis on CMR. The predominant location of LGE was inferolateral in 76% of the patients. The baseline predictive factors of persistent myocarditis at one year were a higher troponin peak (3.8 ug/L vs. 9.3 ug/L, P < 0.001) and a higher initial extent of LGE based on CMR “SQS score” (4.41 vs. 8.82, P < 0.001). On clinical FU, one patient experienced cardiac death before the one-year CMR control and had precisely persistent myocarditis at three months. Moreover, patients with persistent myocarditis were more likely than patients with complete recovery to have premature ventricular contractions during the cardiac stress test (25% versus 7%, P = 0.014). Less than 50% of patients with infarct-like acute myocarditis showed complete healing at one year. We found minor ventricular dysrhythmia at one year and especially a cardiac death in the FU. These results thus highlight the importance of maintaining long-term FU in patients with infarct-like myocarditis, and may lead to modifications in the clinical and therapeutic management of acute myocarditis in routine practice.

More than 30% of symptomatic patients at one year in “infarct like” acute myocarditis

The persistence of symptoms after infarct-like acute myocarditis remains unclear. The objectives of this study were to identify the predictive factors of persistent symptomatic patients at one year in “infarct like” myocarditis. All patients with infarct-like acute myocarditis confirmed by CMR (with typical non-ischemic late gadolinium enhancement (LGE)) were included from 2012 to 2018 at Dijon University Hospital. CMR was performed in the acute phase, at 3 months and 1 year after the acute event. One-year FU included ECG, cardiac stress test, Holter recording, biological assessments, medical history and a QoL questionnaire. Patients were classified according to symptoms (chest pain or dyspnea) at one year. 111 patients were included. At one year, 31% of the patients report symptoms while 53% of them had persistent myocarditis on CMR. Among symptomatic patients, 23% reported intermittent chest pain and 20% reported dyspnea. One patient experienced cardiac death before the one-year CMR control and had persistent myocarditis at 3 months. The predictive factors of persistent symptoms at 1 year were left ventricular dysfunction ( P = 0,005) and wall abnormalities ( P = 0,005) on one year CMR, and hospitalization in the year ( P = 0,002). Nevertheless, symptomatic patients more often had beta blocker treatment than asymptomatic patients (17% vs. 48%, P = 0,001). The initial extent of LGE and persistent myocarditis on CMR at one year didn’t seem to be predictors of the persistence of symptoms. On third of patients with “infarct like” acute myocarditis reported persistent symptoms at 1 year while less than 50% of patients showed complete healing at one year. Persistent symptoms appear to be more related to left ventricular dysfunction than persistent myocarditis, and are associated with greater cardio-protective therapy. These results thus highlight the importance of maintaining long-term FU in patients with infarct-like myocarditis.

More than 50% of non-healing at one year in “infarct like” acute myocarditis evaluated by cardiac magnetic resonance

Cardiac Magnetic Resonance (CMR) has emerged as a reference tool for the diagnosis of myocarditis but its role in follow-up (FU) after the acute event is unknown. The objectives of our study 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 myocarditis at one year and the long-term prognosis of this infarct-like form. All patients with infarct-like acute myocarditis confirmed by CMR were included from April 2012 to January 2018 in this prospective study at Dijon University Hospital. CMR was performed within 7 days following symptom onset, at 3 months and one year after the acute event. One-year FU included ECG, a cardiac stress test, Holter recording, biological assessments and medical history. Patients were classified according to the presence or absence of complete healing at one-year, based on the CMR evaluation. One hundred and eleven patients were included. At one year, 59 patients (53%) exhibited persistent myocarditis on CMR. The baseline predictive factors of persistent myocarditis at one year were a higher troponin peak (3,8 ug/L vs. 9,3 ug/L, P < 0,001) and a higher initial extent of LGE based on CMR “SQS score” (4,41 vs. 8,82, P < 0,001). On clinical FU, one patient experienced cardiac death before the one-year CMR control and had precisely persistent myocarditis at three months. Moreover, patients with persistent myocarditis were more likely than patients with complete recovery to have premature ventricular contractions during the cardiac stress test (25% versus 7%, P = 0.014). Less than 50% of patients with infarct-like acute myocarditis showed complete healing at one year and one patient experienced cardiac death. These results thus highlight the importance of maintaining long-term FU in patients with infarct-like myocarditis.

P1381 The utility of left ventricle deformation in patients with myocarditis with midle-range and preserved ejection fraction

Abstract Background Predicting malignant ventricular arrhythmias and heart failure in patients (pts) with acute myocarditis and middle-range and preserved EF is challenge Aim: to define whether quantification of myocardial mechanics in early, acute phase of myocarditis offers more information to predict six months outcome of patients.Methods: In the 36 consecutive pts with myocarditis, middle age 32.86 ± 12.04yr, 75% males, echocardiography exam was done 1-3 day of diseases, including conventional parameters and comprehensive speckle tracking LV deformation analysis with longitudinal (L), circumferential (C) strain (S;%), strain rate (SR, 1/sec) and rotational LV mechanics. Results: The most patients were present as infarct-like myocarditis (80.56%), the others patients were present as heart failure-like (11.11%) and arrhythmia-like myocarditis (8.33%). At admission 27 (90%) pts had chest pain, 20 (66.7%) pts had ECG changes, 15 (50%) pts had symptoms of heart failure, 5 (16.7%) pts had arrhythmias. Amount of edema and fibrosis assessed by cardiovascular magnetic resonance (CMR) and echo correlate significantly. Classical and conventional parameters of LV systolic function, and deformation were not significantly different between groups. However, mechanical dispersion index (IMD) of global LS and systolic S were significantly different between groups (p &amp;lt; 0.05). Conclusion: Myocardial deformation imaging, like speckle tracking echocardiography, offers deeper insight into complex mechanical abnormalities during not only LV contraction but LV relaxation in longitudinal directions in patients with acute myocarditis. Infarct-like Arrhythmia-like Heart failure-like p EF (%) 57.5 ± 5.42 54.7 ± 12.9 58.3 ± 6.8 NS GLS endo (%) -20.8 ± 2.59 -19.78 ± 2.27 -17.36 ± 5.65 NS GLS (mid (%) -18.31 ± 2.4 -17.31 ± 1.52 -15.3 ± 5.10 NS GLS epi (%) -16.15 ± 2.28 -15.20 ± 0.92 -13.55 ± 4.68 NS IMD LS (ms) 37.04 ± 7.71 33.04 ± 6.58 60.75 ± 38.56 0.008 CS endo (%) -26.39 ± 6.93 -21.59 ± 3.88 -25.17 ± 6.48 NS CS mid (%) -17.32 ± 6.77 -13.03 ± 2.07 -15.95 ± 4.41 NS CS epi (%) -10.99 ± 6.89 -7.13 ± 0.72 -9.53 ± 2.73 NS IMD CS (ms) 47.69 ± 8.86 41.43 ± 23.92 41.01 ± 20.51 NS IMD SL peak S* 12.27 (21) 13.96 (4) 20.28 (84) 0.042 *Median and range values are presented.

Different Myocardial Perfusion Status in Acute Myocardial Infarction and Infarct-like Myocarditis: A Novel Intravoxel Incoherent Motion Diffusion-weighted Imaging based MRI Study

The following study evaluated the diagnostic value of myocardial perfusion in patients with acute myocardial infarction (AMI) and "infarct-like myocarditis" using Intravoxel Incoherent Motion-Diffusion Weighted Imaging (IVIM-DWI imaging). CMR data from 20 patients with suspected AMI, 20 patients with "infarct-like myocarditis" and 20 volunteers were retrospectively analyzed. IVIM-DWI data were acquired using multi-b value single-shot spin-echo echo-planar imaging sequence. IVIM-DWI data were generated according to the 16-segments AHA-model. Cine sequences covering left and right ventricle in short axis and three long axis were analyzed using a dedicated tissue-tracking algorithm. Overall, the AMI T2+ segments exhibited decreased apparent diffusion coefficient (ADC), ADCslow, ADC fast and f values (1.39 ± 0.23 μm2/ms, 1.36 ± 0.23 μm2/ms, 70.77 ± 7.04 μm2/ms, and 0.1243 ± 0.01, respectively) compared to infarct-like myocarditis T2+ (1.48 ± 0.11 μm2/ms, 1.44 ± 0.11 μm2/ms, 87.66 ± 12.50 μm2/ms, and 0.1411 ± 0.02, respectively) and normal controls (1.55 ± 0.07 μm2/ms, 1.52 ± 0.06 μm2/ms, 108.84 ± 4.06 μm2/ms, and 0.1599 ± 0.01, respectively) (all p < 0.05). In addition, AMI LGE+ segments showed significantly lower IVIM-DWI associated parameters (1.34 ± 0.21 μm2/ms, 1.31 ± 0.21 μm2/ms, 68.75 ± 6.33μm2/ms, and 0.1198 ± 0.01) compared to infarct-like myocarditis LGE+ (1.42 ± 0.06 μm2/ms, 1.38 ± 0.08 μm2/ms, 79.12 ± 5.70 μm2/ms, and 0.1313 ± 0.02) (p < 0.05). Moreover, left ventricular peak subendo and subepi radial, circumferential, and longitudinal strain were lower in AMI T2+ segments than in infarct-like myocarditis T2+ segments and normal controls (p < 0.05); AMI LGE+ segments exhibited the lowest strain in three orientations compared to other subgroups (p < 0.05). These findings prove that IVIM-DWI may be used as a reliable sequence for evaluation of different myocardial perfusion patterns in AMI and infarct-like myocarditis. AMI may exhibit lower myocardial perfusion status compared to infarct-like myocarditis due to different pathophysiological process.

More than 50% of non-healing at one year in “infarct-like” acute myocarditis evaluated by Cardiac Magnetic Resonance

Cardiac Magnetic Resonance (CMR) has emerged as a reference tool for the non-invasive diagnosis of myocarditis but its role in follow-up (FU) after the acute event is unknown. We aimed 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 myocarditis at one year and the long-term prognosis of this infarct-like form. All patients with infarct-like acute myocarditis confirmed by CMR (with typical non-ischemic late gadolinium enhancement (LGE)) were included from April 2012 to January 2017 in this prospective single-center study at Dijon University Hospital. CMR was performed within 7 days following symptom onset, at 3 months and one year after the acute event. 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 healing at one year, based on the CMR evaluation. A total of 85 patients were included. At one year, 44 patients (52%) exhibited persistent myocarditis on CMR. Multivariate analysis showed that high peak troponin at the acute phase (OR 8.2, 95%CI 1.63–41.20, P = 0.011) and the initial extent of LGE (OR 1.1, 95%CI 1.02–1.23, P = 0.019) were independent predictors of persistent myocarditis at one year. No patients experienced major adverse cardiac events (cardiac death or serious rhythm disorders). Moreover, patients with persistent myocarditis were more likely than patients with complete recovery to have premature ventricular contractions during the cardiac stress test (31% versus 6%, P = 0.006). Less than 50% of patients with infarct-like acute myocarditis showed complete healing at one year. Although no MACE were found, these results thus highlight the importance of maintaining long-term FU in patients with infarct-like myocarditis.

More than 50% of non-healing at one year in “infarct like” acute myocarditis evaluated by Cardiac Magnetic Resonance

Cardiac Magnetic Resonance (CMR) has emerged as a reference tool for the non-invasive diagnosis of myocarditis but its role in follow-up (FU) after the acute event is unknown. 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 myocarditis at one year and the long-term prognosis of this infarct-like form. All patients with infarct-like acute myocarditis confirmed by CMR (with typical non-ischemic late gadolinium enhancement (LGE)) were included from April 2012 to January 2017 in this prospective single-center study at Dijon University Hospital. CMR was performed within 7 days following symptom onset, at 3 months and one year after the acute event. 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 healing at one-year, based on the CMR evaluation. In total, 85 patients were included. At one year, 44 patients (52%) exhibited persistent myocarditis on CMR. Multivariate analysis showed that high peak troponin at the acute phase (OR 8.2–95%CI 1.63–41.20– P = 0.011) and the initial extent of LGE (OR 1.1–95%CI 1.02–1.23– P = 0.019) were independent predictors of persistent myocarditis at one year. No patients experienced major adverse cardiac events (cardiac death or serious rhythm disorders). Moreover, patients with persistent myocarditis were more likely than patients with complete recovery to have premature ventricular contractions during the cardiac stress test (31% versus 6%, P = 0.006). Less than 50% of patients with infarct-like acute myocarditis showed complete healing at one year. Although no MACE were found, these results thus highlight the importance of maintaining long-term FU in patients with infarct-like myocarditis.

Cardiac MRI Texture Analysis of T1 and T2 Maps in Patients with Infarctlike Acute Myocarditis.

Purpose To assess the diagnostic potential of texture analysis applied to T1 and T2 maps obtained with cardiac MRI for the diagnosis of acute infarctlike myocarditis. Materials and Methods This prospective study from August 2012 to May 2015 included 39 participants (overall mean age ± standard deviation, 34.7 years ± 12.2 [range, 18-63 years]; mean age of women, 46.1 years ± 10.8 [range, 24-63 years]; mean age of men, 29.8 years ± 9.2 [range, 18-56 years]) from the Magnetic Resonance Imaging in Myocarditis (MyoRacer) trial with clinical suspicion of acute myocarditis and infarctlike presentation. Participants underwent biventricular endomyocardial biopsy, cardiac catheterization, and cardiac MRI at 1.5 T, in which native T1 and T2 mapping as well as Lake Louise criteria (LLC) were assessed. Texture analysis was applied on T1 and T2 maps by using a freely available software package. Stepwise dimension reduction and texture feature selection was performed for selecting features enabling the diagnosis of myocarditis by using endomyocardial biopsy as the reference standard. Results Endomyocardial biopsy confirmed the diagnosis of acute myocarditis in 26 patients, whereas 13 participants had no signs of acute inflammation. Mean T1 and T2 values and LLC showed a low diagnostic performance, with area under the curve in receiver operating curve analyses as follows: 0.65 (95% confidence interval [CI]: 0.45, 0.85) for T1, 0.67 (95% CI: 0.49, 0.85) for T2, and 0.62 (95% CI: 0.42, 0.79) for LLC. Combining the texture features T2 run-length nonuniformity and gray-level nonuniformity resulted in higher diagnostic performance with an area under the curve of 0.88 (95% CI: 0.73, 1.00) (P < .001) and a sensitivity and specificity of 89% [95% CI: 81%, 93%] and 92% [95% CI: 77%, 93%], respectively. Conclusion Texture analysis of T2 maps shows high sensitivity and specificity for the diagnosis of acute infarctlike myocarditis. © RSNA, 2018 Online supplemental material is available for this article.

Should we fear infarct-like myocarditis?

IntroductionInfarct-like myocarditis is the common presentation of acute myocarditis with a good prognosis, mentioned in the literature. The restriction of physical activity for up to 6 months is usually recommended. The aim of our study was to show the characteristic features and specificity of this particular presentation of myocarditis and to evaluate its prognosis, relative to physical activity, after hospital discharge. MethodsFrom 2012 to 2016, 93 patients were hospitalized with acute myocarditis at the University Hospital of Pilsen, 73 (78%) of them had infarct-like myocarditis and were evaluated by basic diagnostic parameters.Thirty-two patients with infarct-like myocarditis were involved in our prospective observational study where echocardiography (ECHO), magnetic resonance imaging (MRI) including late gadolinium enhancement (LGE) volume, bicycle ergometry (BE) as well as troponin screening tests were regularly performed. None of the patients were professional athletes.One month after hospital discharge, all patients underwent bicycle ergometry without any load limitation. After the 1-month follow-up, patients were allowed to increase physical exertion gradually to included job performance. ResultsInitially, mild left ventricular systolic dysfunction was found in 43.8%, that was normalized before the first outpatient follow-up. Other patients had normal systolic function. Initially, all of the patients had significantly elevated troponin level. After 1 and 6 months, hypersensitive troponin values were under the 99th percentile of the healthy population. All of the patients had positive LGE in subepicardial localization. After 1 month, the LGE volume median had decreased by up to 53% and after 6 months it had decreased by up to 40% of the original value. The achieved exertion during BE, at the 6-month follow-up (9.7±2.2 METs) was statistically significantly better than after the 1-month follow-up (8.9±2.1 METs, p=0.0023). On the last BE follow-ups (9.3±2.1 METs), no significant change was seen (p=0.2331). The average follow-up time was 2 years. ConclusionInfarct-like myocarditis was the most common presentation of acute myocarditis during the observation time. No patient had an early recurrence of the disease (i.e., within 1 year) and no left ventricular (LV) systolic dysfunction was developed. Infarct-like myocarditis has a specific feature that differs from other types of myocarditis. It has good prognosis, which is independent of physical exertion starting 1 month after hospital discharge.

Evolution of CMR late gadolinium enhancement extent 3 months after “infarct-like” acute myocarditis

The role of cardiac magnetic resonance (CMR in the follow-up after the acute myocarditis is unknown. The objectives of our study were to assess the evolution of CMR parameters between the acute phase of infarct-like myocarditis and 3 months thereafter. All patients with chest pain associated with acute myocarditis confirmed by CMR [with typical delayed myocardial enhancement after gadolinium injection (LGE)] were included from April 2012 to October 2016. CMR was performed within 7 days following symptom onset and 3 months thereafter. Eighty-five patients were included. The predominant location of LGE was anteroseptoapical in nine patients, infero-lateral in 63 patients and diffuse in 13 patients. Twenty-one patients (25%) had no significant (< 10%) regression in LGE extent between the acute phase and 3 months The baseline factors significantly associated with absence of LGE regression were previous hypertension, a lower peak troponin value and a higher initial extent of LGE. Moreover, there was a trend toward significantly older patients and lower creatinine clearance in the group without LGE regression. After multivariate analysis, only an initial LGE extent > 10% of the LV was significantly associated with absence of significant LGE regression at 3-month follow-up ( OR : 3.52, 95%CI: 1.06–11.72, P = 0.041). Moreover, when compared with patients experiencing significant LGE regression, those without significant LGE regression 3 months after the first CMR more often had adverse remodeling of the left ventricle as assessed by a delta end-systolic volume > 10% (43% vs 16%, P = 0.012). Three months after acute “infarct-like” myocarditis, a high proportion of patient had no significant reduction in LGE extent. The relationship between 3-month CMR findings and the onset of clinical and functional outcomes at one-year follow-up will be evaluated soon.

Functional and Morphological Parameters with Tissue Characterization of Cardiovascular Magnetic Imaging in Clinically Verified "Infarct-like Myocarditis".

Cardiac magnetic resonance (CMR) has increasingly proved to be a valuable diagnostic tool for evaluating patients with suspected myocarditis. The objective of this study was to evaluate the diagnostic value of functional and morphological parameters including tissue characterization in patients with "infarct-like myocarditis". 43 patients with clinically verified cases of "infarct-like myocarditis" (median time to MRI scanning after admission for acute symptoms 3 days) and 35 control patients matched by age and sex were included in this retrospective case control study. In this study we used a 1.5 T MRI scanner conducting steady-state-free-precession sequences, T2-weighted imaging, T1-weighted imaging before and after contrast administration and late gadolinium enhancement sequences. According to the recommendations for CMR diagnosis of myocarditis (Lake Louise consensus criteria), a scan was positive for acute myocarditis if 2 of 3 CMR criteria were present. 30 % of the patients with "infarct-like myocarditis" had a reduced left ventricular ejection fraction, 11 % had an increased LV end-diastolic volume index and 35 % had an increased LV mass index. The sensitivity of wall motion abnormalities was 63 % with a regional distribution in 49 %. In 47 % of cases regional wall motion abnormalities were present in the lateral left ventricular segments. Pericardial effusions were discovered in 65 % of cases with a circular appearance in 21 % and focal manifestation in 44 %. The diagnostic sensitivity, specificity, and accuracy of CMR in patients with "infarct-like myocarditis" were 67 %, 100 % and 82 %, respectively. The LGE alone was the most sensitive test parameter with 86 %, providing a specificity of 100 % and accuracy of 92 %. Our study results can be applied to the subgroup of patients with "infarct-like myocarditis", where we found that LGE alone was the most sensitive test parameter. In addition to tissue characterization, the functional and morphological analysis of patients with acute myocarditis provides a useful further diagnostic tool. •Infarct-like myocarditis can be diagnosed by CMR with high validity and reliability. •LGE allone performed best with a sensitivity of 86 %. •Functional and morphological CMR parameters in addition to tissue characterization are useful tool in the diagnosis of acute myocarditis.

Infarct‐like Acute Myocarditis: Relation Between Electrocardiographic Findings and Myocardial Damage as Assessed by Cardiac Magnetic Resonance Imaging

Acute myocarditis (AM) may occasionally have an infarct-like presentation. The aim of the present study was to investigate the relation between electrocardiographic (ECG) findings in this group of patients and myocardial damage assessed by cardiac magnetic resonance imaging (MRI) with the late gadolinium enhancement (LGE) technique. Myocardial damage may be associated with ECG changes in infarct-like AM. Forty-one consecutive patients (36 males; mean age, 36 ± 12 years) with diagnosis of AM according to cardiac MRI Lake Louise criteria and infarct-like presentation were included. The relation between site of ST-segment elevation (STE), sum of STE (sumSTE), time to normalization of STE, and development of negative T wave with the extent of LGE (expressed as % of left ventricular mass [%LV LGE]), was evaluated. Most (80%) patients presented with inferolateral STE; mean sumSTE was 5 ± 3 mm. Normalization of STE occurred within 24 hours in 20 (49%) patients. Development of negative T wave occurred in 28 (68%) patients. Cardiac MRI showed LGE in all patients; mean %LV LGE was 9.6 ± 7.2%. Topographic agreement between site of STE and LGE was 68%. At multivariate analysis, sumSTE (β = 0.42, P < 0.001), normalization of STE >24 hours (β = 0.39, P < 0.001), and development of negative T wave (β = 0.49, P < 0.001) were independently related to %LV LGE. Analysis of the site of STE underestimates the extent of myocardial injury among patients with infarct-like myocarditis. However, some ECG features (ie, sumSTE, normalization of STE >24 hours, and development of negative T wave) may help to identify patients with larger areas of myocardial damage.