Stroke is a serious complication after acute myocardial infarction (AMI) and is associated with an increased risk of death. Though the pathophysiological mechanisms are not exactly known, increased inflammation and platelet reactivity could play an important role in the occurrence of stroke during AMI. We aimed to investigate the relationship between both mean platelet volume (MPV), a parameter of platelet function, and C-reactive protein (CRP) and the occurrence of in-hospital ischemic stroke (IHS) after AMI. Data were obtained from a French regional survey for AMI that included 5976 patients admitted to an intensive care unit (ICU) between 2001 and 2010. Patients were divided into two groups according to the occurrence of IHS. MPV, platelet count (PC), and CRP were routinely measured at admission to the ICU; 99 (1.6%) IHSs were recorded during hospitalization after admission for AMI. In multivariate analysis, IHS was independently associated with a history of stroke (OR: 1.99%, CI: 1.1-3.49, p = 0.01), impaired left ventricular ejection fraction <40% (OR: 1.88, 95% CI: 1.20-2.94, p = 0.006), impaired renal function (OR: 1.94, 95% CI: 1.27-2.95, p = 0.002), CRP > 10 mg/l (OR: 2.19, 95% CI: 1.44-3.33, p < 0.001), and MPV/PC ratio (OR: 1.04, 95% CI: 1.01-1.08, p = 0.023). Compared with the first to fourth quintiles, the last quintile of the MPV/PC ratio was associated with higher rates of IHS on survival curve analysis (p = 0.014). At hospital admission, a high MPV/PC ratio and a high level of CRP might help to identify patients at increased risk of IHS. Moreover, these results provide new insights into the potential role played by increased inflammation and platelet reactivity in the occurrence of stroke after AMI.

Background Detection of left atrial appendage thrombus (LAAt) in acute stroke patients can be improved by cardiac computed tomography using prospective electrocardiogram-gated volume acquisition, which was added to the acute stroke computed tomography protocol in our institution in 2018. Aims To evaluate the factors and clinical management associated with LAAt in patients with acute ischemic stroke. Methods We retrospectively included 324 consecutive patients with ischemic stroke from November 2018 to October 2019. Clinical data and post-stroke management were compared in LAAt and no-LAAt patients. Results Thirty-five patients (10.8%; 95%CI 7.4–14.2) had LAAt and 289 had no-LAAt. LAAt patients were significantly older (82 ± 12 vs. 74 ± 14 yo for no-LAAt, p = 0.002), predominantly female (71% vs. 45%, p = 0.004), and were more likely to have previous atrial fibrillation (63% vs. 15%, p < 0.001) and previous stroke (32% vs. 14%, p = 0.005). There was no significant difference between groups in stroke localization or severity scales at admission or at hospital discharge. After multivariable analysis, female sex (odds ratio 2.51; 95%CI 1.09–5.77, p = 0.031), previous atrial fibrillation (odds ratio 4.87; 95%CI 2.11–11.22, p < 0.001), and left atrial volume >86 ml (odds ratio 5.33; 95%CI 1.70–16.69, p = 0.004) were independently associated with LAAt. More than a third of LAAt patients (37%) received acute heparin therapy compared to 13% of no-LAAt patients (p < 0.001). Moreover, despite comparable stroke severity at admission, the mortality rate was markedly higher in the LAAt group than in the no-LAAt group (37% vs. 13%, p < 0.001). Conclusions Cardiac computed tomography for left atrial appendage thrombus evaluation in routine acute stroke imaging protocol could be beneficial for decision-making with regard to the initiation of early anticoagulation.

No abstract

Late gadolinium enhancement (LGE) MRI is the gold standard technique for myocardial viability assessment. Although the technique accurately reflects the damaged tissue, there is no clinical standard to quantify myocardial infarction (MI). Moreover, commercial software used in clinical practice are mostly semi-automatic, and hence require direct intervention of experts. In this work, a new automatic method for MI quantification from LGE-MRI is proposed. Our novel segmentation approach is devised for accurately detecting not only hyper-enhanced lesions, but also microvascular obstruction areas. Moreover, it includes a myocardial disease detection step which extends the algorithm for working under healthy scans. The method is based on a cascade approach where firstly, diseased slices are identified by a convolutional neural network (CNN). Secondly, by means of morphological operations a fast coarse scar segmentation is obtained. Thirdly, the segmentation is refined by a boundary-voxel reclassification strategy using an ensemble of very light CNNs. We tested the method on a LGE-MRI database with healthy (n = 20) and diseased (n = 80) cases following a 5-fold cross-validation scheme. Our approach segmented myocardial scars with an average Dice coefficient of 77.22 ± 14.3% and with a volumetric error of 1.0 ± 6.9 cm3. In a comparison against nine reference algorithms, the proposed method achieved the highest agreement in volumetric scar quantification with the expert delineations (p< 0.001 when compared to the other approaches). Moreover, it was able to reproduce the scar segmentation intra- and inter-rater variability. Our approach was shown to be a good first attempt towards automatic and accurate myocardial scar segmentation, although validation over larger LGE-MRI databases is needed.

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.