[Management of acute myocardial infarction with ST-segment elevation: Update 2013]

This article gives an update on the management of ST-segment elevation myocardial infarction (STEMI) according to guidelines released in 2012 by the European Society of Cardiology. To ensure a reliable diagnosis the updated universal definition of myocardial infarction will also be covered which is defined by myocardial necrosis. Criteria for diagnosis are a rise or fall of cardiac biomarkers, preferably troponin, in conjunction with symptoms of myocardial ischemia, new repolarisation disorders or left bundle branch block, development of pathological Q-waves, new hypokinesia/akinesia or loss in viability or the detection of intracoronary thrombi during cardiac catheterization or autopsy. The current recommendations for primary diagnosis and treatment by the first medical contact will also be discussed and contains decision-making for the optimal reperfusion strategy. Primary percutaneous coronary intervention remains the preferred reperfusion strategy; however, specifications with respect to time for diagnosis and reperfusion have been introduced. Furthermore, establishing a STEMI network has been emphasized in more detail. Special attention is paid to the new antiplatelet agents and anticoagulation therapy where prasugrel and ticagrelor are currently preferred over clopidogrel.

[Treatment of cardiogenic shock: what is proven?]

This review will address the pathophysiology, incidence, current outcome and treatment options of patients with cardiogenic shock complicating acute myocardial infarction. The major focus will be on the current evidence based on randomized clinical trials and the current guideline recommendations for the treatment of cardiogenic shock.

Reperfusion strategies in ST-segment elevation myocardial infarction

ST-elevation myocardial infarction (STEMI) is a major cause of morbidity and mortality worldwide. Emergent reperfusion of the infarct related artery is the cornerstone of STEMI treatment in order to salvage myocardium and improve cardiovascular outcome. Basically, reperfusion strategies include fibrinolysis, primary percutaneous coronary intervention (PCI) or the combination of both methods. Clinical studies indicate that primary PCI is superior to fibrinolytic therapy when performed rapidly at experienced centers. However, physicians are often faced with the decision to either accept PCI-related delays due to transfer or to administer fibrinolysis immediately. A well structured regional system of STEMI care helps to select the appropriate reperfusion strategy and guarantee timely restoration of coronary blood flow. This article reviews the evidence behind the respective reperfusion therapies and summarizes current guidelines for STEMI management.

[MRI for myocarditis]

Cardiovascular magnetic resonance imaging (CMRI) has become the primary tool for the non-invasive assessment in patients with suspected myocarditis, especially after exclusion of acute coronary syndrome (ACS) for the differential diagnosis. Various MRI parameters are available which have different accuracies. Volumetric and functional ventricular assessment and the occurrence of pericardial effusion alone demonstrate only a poor sensitivity and specificity. The calculation of the T2-ratio (edema assessment), the early or global relative myocardial enhancement (gRE) and the late gadolinium enhancement (LGE), which represents irreversibly injured myocardium, are more specific parameters. All MRI parameters demonstrate the best accuracy in infarct-like acute myocarditis, whereas in chronic myocarditis sensitivity and specificity are less accurate. Therefore, a multisequential (at least two out of three parameters are positive) approach is recommended. The assessment of the value of newer, more quantitative MRI sequences, such as T1 and T2-mapping is still under investigation.

[Diagnostic work-up of coronary artery disease: Clinical value of different imaging methods]

This continuing medical education (CME) article describes the different non-invasive imaging methods with the exception of positron emission tomography for ischemia and viability testing. While stress methods, such as myocardial scintigraphy, stress echo or stress magnetic resonance imaging can detect the functional relevance of coronary artery stenosis, multislice computed tomography allows the visualization of the coronary anatomy and potential stenoses. Recently developed hybrid imaging allows the coronary anatomy and simultaneous functional testing of ischemia to be depicted. The different imaging methods for ischemia and viability testing are described.

Exploring three-dimensional matrix-assisted laser desorption/ionization imaging mass spectrometry data: three-dimensional spatial segmentation of mouse kidney

Three-dimensional (3D) imaging has a significant impact on many challenges of life sciences. Three-dimensional matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) is an emerging label-free bioanalytical technique capturing the spatial distribution of hundreds of molecular compounds in 3D by providing a MALDI mass spectrum for each spatial point of a 3D sample. Currently, 3D MALDI-IMS cannot tap its full potential due to the lack efficient computational methods for constructing, processing, and visualizing large and complex 3D MALDI-IMS data. We present a new pipeline of efficient computational methods, which enables analysis and interpretation of a 3D MALDI-IMS data set. Construction of a MALDI-IMS data set was done according to the state-of-the-art protocols and involved sample preparation, spectra acquisition, spectra preprocessing, and registration of serial sections. For analysis and interpretation of 3D MALDI-IMS data, we applied the spatial segmentation approach which is well-accepted in analysis of two-dimensional (2D) MALDI-IMS data. In line with 2D data analysis, we used edge-preserving 3D image denoising prior to segmentation to reduce strong and chaotic spectrum-to-spectrum variation. For segmentation, we used an efficient clustering method, called bisecting k-means, which is optimized for hierarchical clustering of a large 3D MALDI-IMS data set. Using the proposed pipeline, we analyzed a central part of a mouse kidney using 33 serial sections of 3.5 μm thickness after the PAXgene tissue fixation and paraffin embedding. For each serial section, a 2D MALDI-IMS data set was acquired following the standard protocols with the high spatial resolution of 50 μm. Altogether, 512 495 mass spectra were acquired that corresponds to approximately 50 gigabytes of data. After registration of serial sections into a 3D data set, our computational pipeline allowed us to reveal the 3D kidney anatomical structure based on mass spectrometry data only. Finally, automated analysis discovered molecular masses colocalized with major anatomical regions. In the same way, the proposed pipeline can be used for analysis and interpretation of any 3D MALDI-IMS data set in particular of pathological cases.

Proteomic pattern analysis discriminates among multiple sclerosis-related disorders

OBJECTIVE

To use a new, unbiased biomarker discovery strategy to obtain and assess proteomic data from cerebrospinal fluid (CSF) of patients with multiple sclerosis (MS)-related disorders.

METHODS

CSF protein profiles were analyzed from 107 patients with either MS-related disorders (including relapsing remitting MS [RRMS], primary progressive MS [PPMS], anti-aquaporin4 antibody seropositive-neuromyelitis optica spectrum disorder [SP-NMOSD], and seronegative-NMOSD with long cord lesions on spinal magnetic resonance imaging [SN-NMOSD]), amyotrophic lateral sclerosis (ALS), or other inflammatory neurological diseases (used as controls). CSF peptides/proteins were purified with magnetic beads, and directly measured by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The obtained spectra were analyzed with multivariate statistics and pattern matching algorithms. These analyses were replicated in an independent sample set of 84 patients composed of those with MS-related disorders or with other neurological diseases (the second cohort).

RESULTS

MS-related disorders differed considerably in terms of CSF protein profiles. SP-NMOSD and SN-NMOSD, both of which fit within the NMO spectrum, were distinguishable from RRMS with high cross-validation accuracy on a support vector machine classifier, especially in relapse phases. Some peaks derived from samples of relapsed SP-NMOSD can discriminate RRMS with high area under curve scores (>0.95) and this was reproduced on the second cohort. The similarity of proteomic patterns between selected neurological diseases were demonstrated by pattern matching analysis. To our surprise, the spectral differences between RRMS and PPMS were much larger than those of PPMS and ALS.

INTERPRETATION

Our findings suggest that CSF proteomic pattern analysis can increase the accuracy of disease diagnosis of MS-related disorders and will aid physicians in appropriate therapeutic decision-making.

Abstract 1272: MALDI imaging and next generation sequencing for dissecting prostate cancer heterogeneity

Prostate cancer is often heterogeneous with multiple tumor foci within the same prostate. MALDI (Matrix-Assisted Laser Desorption/Ionization) mass spectrometry imaging (MSI) allows for a comprehensive profiling of the molecular phenotype on the protein, peptide, lipid, and metabolite level across entire tissue slides without prior enrichment of tumor cells. This study aims in a MALDI-based discrimination of cancer areas that are heterogeneous with respect to morphology and molecular features. We established a method for cryopreservation of entire prostates from cancer patients, and build tissue microarrays from individual cancerous prostates representing >30 different areas of the primary tumor as well as multiple lymph node metastases. We analyzed these arrays for ERG fusion by FISH and for peptide signatures by MALDI MSI. In addition, 2 selected tumor areas and 4 different lymph node metastases from one prostate were subjected to paired end next generation sequencing. MALDI identified 5 masses that were specific for epithelial cells. One particular mass was strongly related to presence of ERG fusion. In one prostate, we identified another mass that was present only in 2/35 tissue spots from the primary tumor as well as in 4/10 lymph nodes. Deep sequencing of different tumor areas of this case identified distinct patterns of structural genetic alterations. A cluster analysis showed that all samples were clonally related, and identified the area inside the primary tumor that gave rise to the metastases. In conclusion, these data suggest that MALDI imaging and next generation sequencing allow for identification of genetic and proteome patterns that correspond to metastatic spread of prostate cancer cells. A combination of both techniques is suited to dissect the genetic background of distinct MALDI signatures.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1272. doi:1538-7445.AM2012-1272