[Diagnostic and prognostic utility of cardiac magnetic resonance imaging in myocarditis]. / Apports diagnostique et pronostique de l'imagerie par résonance magnétique cardiaque dans la myocardite.

Cardiac magnetic resonance imaging (CMR) became over the last 30 years an essential tool in the management of patients with myocarditis. Noninvasive diagnosis of acute myocarditis relies on a clinical picture compatible with myocarditis and fulfilling of the updated 2018 Lake Louise criteria. These criteria include highlights of myocardial edema by conventional T2-weighted sequences or by T2 mapping in one hand and evidence of myocardial injury using late gadolinium enhancement sequences, T1 mapping or extra-cellular volume measurement in the other hand. It is recommended to perform basal examination in the 2 or 3 weeks following acute episode and to repeat CMR during follow-up. The literature reports excellent diagnostic accuracy, between 80% and 90%, making CMR a robust and reliable noninvasive alternative to endomyocardial biopsy. Besides, beyond its diagnostic performance, CMR can also help to identify patients with unfavourable long-term outcome. For instance, medio-ventricular and septal location of late gadolinium enhancement, degree of late gadolinium enhancement extent or high T2 mapping values are independent predictive factors of major cardio-vascular events.

Prevalence, Characteristics, and Outcomes of COVID-19-Associated Acute Myocarditis.

BACKGROUND: Acute myocarditis (AM) is thought to be a rare cardiovascular complication of COVID-19, although minimal data are available beyond case reports. We aim to report the prevalence, baseline characteristics, in-hospital management, and outcomes for patients with COVID-19-associated AM on the basis of a retrospective cohort from 23 hospitals in the United States and Europe. METHODS: A total of 112 patients with suspected AM from 56 963 hospitalized patients with COVID-19 were evaluated between February 1, 2020, and April 30, 2021. Inclusion criteria were hospitalization for COVID-19 and a diagnosis of AM on the basis of endomyocardial biopsy or increased troponin level plus typical signs of AM on cardiac magnetic resonance imaging. We identified 97 patients with possible AM, and among them, 54 patients with definite/probable AM supported by endomyocardial biopsy in 17 (31.5%) patients or magnetic resonance imaging in 50 (92.6%). We analyzed patient characteristics, treatments, and outcomes among all COVID-19-associated AM. RESULTS: AM prevalence among hospitalized patients with COVID-19 was 2.4 per 1000 hospitalizations considering definite/probable and 4.1 per 1000 considering also possible AM. The median age of definite/probable cases was 38 years, and 38.9% were female. On admission, chest pain and dyspnea were the most frequent symptoms (55.5% and 53.7%, respectively). Thirty-one cases (57.4%) occurred in the absence of COVID-19-associated pneumonia. Twenty-one (38.9%) had a fulminant presentation requiring inotropic support or temporary mechanical circulatory support. The composite of in-hospital mortality or temporary mechanical circulatory support occurred in 20.4%. At 120 days, estimated mortality was 6.6%, 15.1% in patients with associated pneumonia versus 0% in patients without pneumonia (P=0.044). During hospitalization, left ventricular ejection fraction, assessed by echocardiography, improved from a median of 40% on admission to 55% at discharge (n=47; P<0.0001) similarly in patients with or without pneumonia. Corticosteroids were frequently administered (55.5%). CONCLUSIONS: AM occurrence is estimated between 2.4 and 4.1 out of 1000 patients hospitalized for COVID-19. The majority of AM occurs in the absence of pneumonia and is often complicated by hemodynamic instability. AM is a rare complication in patients hospitalized for COVID-19, with an outcome that differs on the basis of the presence of concomitant pneumonia.

Clinical characterization of dysautonomia in long COVID-19 patients.

Increasing numbers of COVID-19 patients, continue to experience symptoms months after recovering from mild cases of COVID-19. Amongst these symptoms, several are related to neurological manifestations, including fatigue, anosmia, hypogeusia, headaches and hypoxia. However, the involvement of the autonomic nervous system, expressed by a dysautonomia, which can aggregate all these neurological symptoms has not been prominently reported. Here, we hypothesize that dysautonomia, could occur in secondary COVID-19 infection, also referred to as "long COVID" infection. 39 participants were included from December 2020 to January 2021 for assessment by the Department of physical medicine to enhance their physical capabilities: 12 participants with COVID-19 diagnosis and fatigue, 15 participants with COVID-19 diagnosis without fatigue and 12 control participants without COVID-19 diagnosis and without fatigue. Heart rate variability (HRV) during a change in position is commonly measured to diagnose autonomic dysregulation. In this cohort, to reflect HRV, parasympathetic/sympathetic balance was estimated using the NOL index, a multiparameter artificial intelligence-driven index calculated from extracted physiological signals by the PMD-200 pain monitoring system. Repeated-measures mixed-models testing group effect were performed to analyze NOL index changes over time between groups. A significant NOL index dissociation over time between long COVID-19 participants with fatigue and control participants was observed (p = 0.046). A trend towards significant NOL index dissociation over time was observed between long COVID-19 participants without fatigue and control participants (p = 0.109). No difference over time was observed between the two groups of long COVID-19 participants (p = 0.904). Long COVID-19 participants with fatigue may exhibit a dysautonomia characterized by dysregulation of the HRV, that is reflected by the NOL index measurements, compared to control participants. Dysautonomia may explain the persistent symptoms observed in long COVID-19 patients, such as fatigue and hypoxia. Trial registration: The study was approved by the Foch IRB: IRB00012437 (Approval Number: 20-12-02) on December 16, 2020.

IRMA study: Prevalence of subdiaphragmatic visceral infarction in ischemic stroke and atrial fibrillation.

Background Occult atrial fibrillation (AF) may, in part, explain cryptogenic stroke. A 22% prevalence of subdiaphragmatic visceral infarction (SDVI) among patients with ischemic stroke (IS) due to AF has been reported, using abdominal MRI. We sought to assess the reproducibility of this method and to confirm that SDVI is more prevalent in cases of AF-caused IS than in IS of other etiologies. Methods In consecutive patients admitted to our hospital, we compared SDVI prevalence in three groups: patients with IS due to AF (IS+/AF+ group), patients with stroke of another determined cause (IS+/AF- group) and patients with AF without stroke (IS-/AF+ group). Results A total of 111 patients were included. The median time between inclusion and abdominal MRI was six days. SDVI was more frequent in the IS+/AF+ group ( n = 10; 21.3%), than in IS+/AF- ( n = 1; 3.3%) and IS-/AF+ ( n = 0) groups, p = 0.002. The most frequent localization was the kidney. Conclusions The prevalence of SDVI was higher among patients with AF-caused IS. In cases of cryptogenic stroke, a positive abdominal MRI may suggest occult AF as the cause and identify a high risk of AF in this subgroup of patients.

Diagnostic Yield of Venous Thrombosis and Pulmonary Embolism by Combined CT Venography and Pulmonary Angiography in Patients with Cryptogenic Stroke and Patent Foramen Ovale.

BACKGROUND: Paradoxical embolism via a patent foramen ovale (PFO) has been suggested as a potential stroke mechanism. Combined CT venography and pulmonary angiography (CVPA) is a simple, validated and accurate technique to diagnose deep venous thrombosis (DVT) or pulmonary embolism (PE). We sought to assess the prevalence of DVT or PE among patients with PFO and cryptogenic stroke (CS) by CVPA. METHODS: Patients were identified retrospectively from a clinical registry of consecutive patients with stroke admitted to our Stroke Unit. The following criteria were required for inclusion in this study: CS, PFO identified by transthoracic echography using contrast medium and CVPA performed during the hospitalization following stroke. RESULTS: A total of 114 patients with PFO underwent a CVPA within 7 days (interquartile range 4-9) from stroke symptom onset. On cerebral imaging, 11% had multiple infarcts. CVPA documented deep vein thrombosis (DVT) in 10 patients (8.8%) and PE in 5 patients (4.4%), that is, a total of 12 patients with prevalence of 10.5% (95% CI 5.5-17.7). Patients with PE-DVT had higher D-dimers and C reactive protein level than patients without PE-DVT (p < 0.05). CONCLUSION: CVPA may be used by the stroke team in the work-up of suspected paradoxical embolism among cryptogenic ischemic stroke patients with PFO.

Relationship between the ischemic threshold at the onset of wall-motion abnormality on semisupine exercise echocardiography and the extent of coronary artery disease.

Semisupine exercise echocardiography (SSEE) provides the unique opportunity of continuous monitoring of segmental wall motion during physiologic stress. We evaluated the relationship between the ischemic threshold at the onset of wall-motion abnormality on SSEE and the extent of coronary artery disease (CAD) in a consecutive series of 224 patients who underwent coronary angiography. Ischemic threshold was significantly lower for patients with multivessel disease compared with single-vessel disease: maximal workload was 102 versus 135 W (P = 1.3.10(-6)); percentage of maximal predicted heart rate achieved was 64 versus 70% (P =.004); and double product was 21,335 versus 23,389 (P =.03), respectively. Sensitivity, specificity, and positive and negative predictive values of SSEE for the detection of significant CAD (> or =60% diameter stenosis) were 81%, 74%, 90%, and 56%, respectively. SSEE is an accurate tool to diagnose CAD and the ischemic threshold at the onset of wall-motion abnormality is inversely related to the extent of CAD.