Acute myocardial infarction related to coronary artery embolism: A systematic cardiac and cerebral magnetic resonance imaging study.

BACKGROUND: Coronary artery embolism (CAE) is a rare, non-atherosclerotic cause of acute myocardial infarction (MI). Atrial fibrillation (AF) is the most frequent cause of CAE, and can be associated with multiple embolisms, particularly in the brain. AIMS: To characterize CAE-related myocardial injury, assess the proportion of cardiocerebral infarction and characterize brain injuries associated with dual embolism. METHODS: In this prospective study, patients with CAE-associated MI underwent (1) cardiac magnetic resonance imaging (MRI) to assess the extent of infarct transmurality and myocardial necrosis size and (2) brain MRI to assess the proportion of simultaneous cardiocerebral infarction. We screened 1401 consecutive patients with de novo acute MI from January 2019 to June 2021. CAE was diagnosed based on clinical, angiographic and diagnostic imaging criteria. RESULTS: Overall, 29/1401 patients presented with CAE (2.1%), of whom 21 underwent cardiac and cerebral MRI. Of these, nine (43%) had an ischaemic stroke, and AF was the leading cause of CAE in 14 patients (67%). Multiple CAE were common at coronary angiography (33%). Four patients (19%) had left atrial appendage thrombus - 4/9 patients (44%) with a stroke but 0/12 patients without a stroke. On cardiac MRI, the median (interquartile range) number of segments with acute infarction was 3 (0-11) in patients with stroke and 3 (1-6) in those without. Most acute ischaemic strokes (78%) were localized in the superficial sylvian territory and only 2/21 patients (10%) had stroke sequelae. CONCLUSION: MI-related to CAE was associated with infarctions of average size but multiple locations. Systematic brain MRI revealed that 33% of cases were associated with a stroke, which was generally asymptomatic. Further studies are required to better characterize the pathophysiology, clinical course and prognostic value of CAE. Moreover, optimal management strategies remain to be determined.

Detection of Myocardial Infarction by Cardiac Magnetic Resonance in Embolic Stroke Related to First Diagnosed Atrial Fibrillation.

INTRODUCTION: Elevated troponin levels are found in a significant number of patients who are diagnosed with acute embolic stroke (AES) after first diagnosed atrial fibrillation (AF). These myocardial injuries, which are known as cardiocerebral infarction (CCI), are potentially caused by coronary embolism and correspond to simultaneous cardiac and cerebral embolisms. However, this severe condition remains poorly understood. In this prospective study, we aimed to investigate the prevalence and the cardiac magnetic resonance (CMR) characteristics of CCI. MATERIALS AND METHODS: Consecutive patients with first diagnosed AF hospitalized for AES in a neurovascular intensive care unit from 2019 to 2020 were included. Troponin Ic kinetic were measured <72 h, MRI and coronary angiography or CT scan were performed <7 days after admission. Patients with significant coronary lesions were excluded. RESULTS: During the study period, 1150 patients with strokes were hospitalized in the neurovascular intensive care unit (ICU). Of these patients, 955 had an ischemic stroke and 97 had a transient ischemic attack. Among the 44 patients with AES and with first diagnosed AF, 34 patients underwent CMR and CMR analysis identified 12 MI. A significant rise in troponin (>0.10 µg/L) was observed in 35% of the total population (12/34 patients). More specifically, a rise was seen in 23% of the AES without MI group, 58% of the AES with MI. In addition, coronary embolism was identified in 3 patients who underwent coronary angiography (3/12) and MI was often (30%) localized in infero-latero-medial and infero-apical segments. Most AES were localized in the superficial sylvian territory. CONCLUSION: We found a high prevalence of CMR-confirmed double embolization sites in the acute phase of an embolic stroke. Further studies are required to better characterize the pathophysiology, clinical course and prognostic value of CCI. Moreover, optimal management strategies, including antiplatelet therapy, remain to be determined.

Cerebral microbleeds and acute myocardial infarction: Screening and disease progression.

INTRODUCTION: Cerebral microbleeds (CMB) are associated with intracerebral haemorrhage. Therefore they may represent a concern if anticoagulant and/or antiplatelet therapy is needed. The aim of this study was to determine the prevalence of CMB in patients with acute myocardial infarction (AMI), and to follow their progression at 3 months under dual antiplatelet therapy (DAPT). METHODS: This prospective study included patients aged over 60 hospitalized in intensive cardiac care unit in our city for AMI. These patients underwent a first brain Magnetic resonance imaging (MRI) within 72 h of admission, that was repeated 3 months. RESULTS: 108 patients were included between November 2016 and December 2018. The prevalence of CMB was 21.3%, with a female predominance of 65.2% vs 32.1% (p = 0.004). Diabetes is significantly associated with the presence of CMB, 45.5% vs 21.2% (p = 0.021). Patients with at least one acute CMB had higher haemorrhagic risk as evaluated with CRUSADE score (40.5 ± 13.6 vs 31.2 ± 14.8 (p = 0.004).Multivariate analysis showed that only female sex was associated with the presence of a CMB on the initial MRI. On repeated MRI, an increase in CMB was observed in 6% of patients.Our results suggest that discharge treatment with anticoagulant in combination with antiplatelet therapy may be an independent predictor of early progression of CMB. CONCLUSION: Our study confirms the high prevalence of CMB in patients over 60 years with AMI. The association of anticoagulant with DAPT, 3 months after stenting, may be an independent factor of CMB progression.