Eosinophilic myocarditis: from etiology to diagnostics and therapy.

Eosinophilic myocarditis (EM) is a rare, potentially life-threatening, form of inflammatory heart disease characterized by eosinophilic infiltration of the myocardium. Different diseases are involved in its etiopathogeneses, such as eosinophilic granulomatosis with polyangiitis (or Churg-Strauss Syndrome), hypereosinophilic syndromes, parasitic infections, drug reactions, paraneoplastic syndromes and primary immunodeficiencies (e.g. Omenn Syndrome). There is a wide spectrum of clinical pictures at presentation ranging from chronic restrictive cardiomyopathy (Loeffler cardiomyopathy) to acute necrotizing myocarditis with cardiogenic shock. The genetic contribution and the environmental interplay, such as SARS-CoV-2 infection and related vaccines, are fields not well studied yet. Many non-invasive tools, mainly echocardiography and cardiac magnetic resonance imaging, along with invasive procedures, such as endomyocardial biopsy, are the crucial steps in the diagnostic workup. The correct diagnosis is a challenge but mandatory for timely and appropriate immunosuppressive therapy.

Late gadolinium enhancement by cardiovascular magnetic resonance is complementary to left ventricle ejection fraction in predicting prognosis of patients with stable coronary artery disease.

BACKGROUND: Late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) predicts adverse prognosis in patients with stable coronary artery disease (CAD). However, the interaction with conventional risk factors remains uncertain. Our aim was to assess whether the extent of LGE is an independent predictor of adverse cardiac outcome beyond conventional risk factors, including left ventricle ejection fraction (LVEF). METHODS: We enrolled 376 patients (88% males, 64 ± 11 years) with stable CAD, who underwent LGE assessment and a detailed conventional evaluation (clinical and pharmacological history, risk factors, ECG, Echocardiography). During a follow-up of 38 ± 21 months, 56 events occurred (32 deaths, 24 hospitalizations for heart failure). RESULTS: LGE and LVEF showed the strongest univariate associations with end-points (HR: 13.61 [95%C.I.: 7.32-25.31] for LGE ≥ 45% of LV mass; and 12.34 [6.80-22.38] for LVEF ≤ 30%; p < 0.0001). Multivariate analysis identified baseline LVEF, loop diuretic therapy, moderate-severe mitral regurgitation and pulmonary hypertension as significant predictors among conventional risk factors. According to a step-wise approach, LGE showed strong association with prognosis as well (5.25 [2.64-10.43]; p < 0.0001). LGE significantly improved the model predictability (chi-square 239 vs 221, F-test p < 0.0001) with an additive effect on the prognostic power of LVEF, which however retained its prognostic power (4.89 [2.50-09.56]; p < 0.0001). Patients with LGE ≥ 45% and/or LVEF ≤ 30% had much worse prognosis compared to patients without risk factors (annual event rates of 43% vs 3%; p < 0.0001). Interestingly LGE was a significant predictor when all cause mortality was analyzed as the only endpoint. CONCLUSIONS: This study demonstrates that LGE assessed by CMR is a robust independent non-invasive marker of prognosis in stable CAD patients. LGE can integrate the available metrics to substantially improve risk stratification.

Magnetic resonance investigations in Brugada syndrome reveal unexpectedly high rate of structural abnormalities.

AIMS: Recent data suggest that sub-clinical structural abnormalities may be part of the Brugada syndrome (BrS) phenotype, a disease traditionally thought to occur in the structurally normal heart. In this study, we carried out detailed assessment of cardiac morphology and function using cardiac magnetic resonance imaging (CMRI). METHODS AND RESULTS: Thirty consecutive patients with BrS were compared with 30 sex- (26/4 male/female), body surface area- (+/-0.2 m(2)), and age-matched (+/-5 years) normal volunteers. CMRI exam included long- and short-axis ECG-gated breath-hold morphological T1-TSE sequences for fatty infiltration and cine-SSFP sequences for kinetic assessment. Fatty infiltration was not found in any subject. Patients with BrS compared with normal subjects showed higher incidence of mild right ventricle (RV) wall-motion abnormalities [15 (50%) vs. 5 (17%) subjects (P = 0.006) with reduced radial fractional shortening in more than two segments], reduction of outflow tract ejection fraction (49 +/- 11% vs. 55 +/- 10%; P = 0.032), enlargement of the inflow tract diameter (46 +/- 4 vs. 41 +/- 5 mm, P < 0.001 in short-axis; 46 +/- 4 vs. 42 +/- 5 mm, P = 0.001 in four-chamber long-axis view) and area (22 +/- 2 vs. 20 +/- 3 cm(2); P = 0.050), and of global RV end-systolic volume (34 +/- 10 vs. 30 +/- 6 mL/m(2); P = 0.031) but comparable outflow tract dimensions, global RV end-diastolic volume, left ventricle parameters, and atria areas. CONCLUSION: CMRI detects a high prevalence of mild structural changes of the RV, and suggests further pathophysiological complexity in BrS. Prospective studies to assess the long-term evolution of such abnormalities are warranted.

Intra-observer and interobserver reproducibility of right ventricle volumes, function and mass by cardiac magnetic resonance.

OBJECTIVES: Cardiac magnetic resonance (CMR) allows quick and non-invasive evaluation both of right ventricle (RV) volume and function, which are important in many heart diseases. We have evaluated CMR intra- and interobserver reproducibility in different conditions of RV dimension and function. METHODS: We have analysed CMR exams of 45 subjects, randomly selected from our database according to RV end-diastolic volume (EDV; 15-subject groups with EDV < 25th, 25-75th and > 75th percentiles of a normal control population). Selected subjects were of both sexes (male/female 33/12) and of variable age (8-83 years) and body surface (0.9-2.3 m). RV end-diastolic and end-systolic volumes (ESV), ejection fraction (EF) and mass were blindly evaluated by two operators. Bland-Altman bias and coefficient of variability (CoV) were used to assess intra- and interobserver reproducibility. RESULTS: A wide range of EDV (range = 46-239 ml), ESV (20-129 ml) and EF (6-64%) was observed. The intra-observer bias was -5 ml for EDV, -2 ml for ESV, -1% for EF and 5 g for mass, with a CoV of 7-12%. The interobserver bias was 5 ml for EDV, 2 ml for ESV, 2% for EF and 6 g for mass, with a CoV of 8-13%. Analysis by tertiles showed EF assessment variability to be higher in the lower tertiles at intra-observer (P < 0.036) and, above all, at interobserver (P < 0.000) analysis. Mass assessment variability was higher in the upper tertile (P < 0.004) at intra-observer analysis. CONCLUSIONS: Intra- and interobserver reproducibility of RV parameters assessed by CMR are adequate in a wide range of RV dimensions and function. However, caution is required with respect to the significance of small changes of EF and mass in the case of poor function and hypertrophy of the RV, respectively.

Contrast-enhanced cardiac magnetic resonance in a patient with chemotoxic cardiomyopathy.

Gadolinium-enhanced cardiac magnetic resonance was performed in a patient with chemotoxic cardiomyopathy. Intramyocardial midwall linear delayed hyperenhancement was found. Such a finding is consistent with midwall fibrosis and/or myocardial cell loss due to cardiotoxic effect of chemotherapy.

Improved reproducibility of right ventricular volumes and function estimation from cardiac magnetic resonance images using level-set models.

This study aims to assess whether an alternative method, that is based on volumetric surface detection (VoSD) without tracing and is totally free of geometric assumptions, can improve the reproducibility of right ventricular (RV) volume quantification from cardiac magnetic resonance (CMR) images, in comparison with a conventional disk-area technique. In a sample of 23 patients, with wide variability of RV end-diastolic volume (EDV: 47-131 ml), end-systolic volume (ESV: 20-76 ml), and ejection fraction (EF: 29-73%), using the standard method (Argus, Siemens) as the reference, the VoSD method showed good agreement for EDV, ESV, and EF estimations (correlation coefficient: 0.91, 0.94, and 0.94; Bland-Altman biases: 1 ml, 1 ml, and 0%; limits of agreement: +/-16 ml, +/-11 ml, and +/-11%, respectively). An analysis of the reproducibility of the two methods showed lower intraobserver variability for the VoSD method than for the conventional method, as evidenced by the coefficient of variability (CoV) values (2-6% vs. 8-15%; P < 0.05). In addition, the VoSD method showed improved interobserver reproducibility (7-10% vs. 8-15%), but the difference was statistically significant only for EF estimation variability (8 vs. 15%, P < 0.05). In conclusion, the newly developed VoSD technique allows accurate measurements of RV volumes and function, and appears to be more reproducible than the conventional methodology.

Contrast-enhanced magnetic resonance imaging assessment of scar size in patients with chronic myocardial infarction.

BACKGROUND: In the assessment of myocardial infarction (MI) mass, contrast-enhanced magnetic resonance imaging (CE-MRI) is comparable to single-photon emission computed tomography (SPECT). The aim of the present study was to determine whether the MI area, as assessed at CE-MRI and SPECT, is comparable to mass evaluation. We also compared CE-MRI and SPECT estimates of the MI area with functional evaluations made at echocardiography and kinetic MRI (cine-MRI). METHODS: We used a 1.0 Tesla MRI scanner and an inversion-recovery turboFLASH sequence, a tomographic gamma-camera and second-harmonic ultrasound systems. Two blinded operators assessed the extent of scarring, expressed as a percentage of the whole left ventricle (LV), using a 16-segment model. We studied 55 consecutive patients with a clinically stable healed MI (50 Q wave, 5 non-Q wave). RESULTS: The scar mass was 19+/-23% of the LV at CE-MRI and 21+/-25% at SPECT; the scar area was 29+/-23% of the LV at CE-MRI, 41+/-28% at SPECT, 29+/-31% at cine-MRI, and 32+/-29% at echocardiography. The Bland-Altman bias between CE-MRI and SPECT mass estimations was -2% of the LV with a+/-23% limit of agreement (LOA), while the bias between the area assessments was -12% with a+/-42% LOA. Bias between CE-MRI and functional evaluation by cine-MRI and echocardiography was 0% with a+/-39% LOA and -3% with a+/-36% LOA respectively. Comparing SPECT with cine-MRI and echocardiography the bias was 12% with a+/-52% LOA and 9% with a+/-56% LOA respectively. CONCLUSIONS: CE-MRI has proved to be comparable to SPECT in the assessment of the healed MI mass. Conversely, a high systematic error (high bias and LOA) renders CE-MRI and SPECT assessments of the MI area incomparable. Similarly (high bias and/or LOA) CE-MRI and SPECT estimations of the MI area cannot be compared with functional evaluation by echocardiography or cine-MRI.