A hybrid of light-field and light-sheet imaging to study myocardial function and intracardiac blood flow during zebrafish development

Biomechanical forces intimately contribute to cardiac morphogenesis. However, volumetric imaging to investigate the cardiac mechanics with high temporal and spatial resolution remains an imaging challenge. We hereby integrated light-field microscopy (LFM) with light-sheet fluorescence microscopy (LSFM), coupled with a retrospective gating method, to simultaneously access myocardial contraction and intracardiac blood flow at 200 volumes per second. While LSFM allows for the reconstruction of the myocardial function, LFM enables instantaneous acquisition of the intracardiac blood cells traversing across the valves. We further adopted deformable image registration to quantify the ventricular wall displacement and particle tracking velocimetry to monitor intracardiac blood flow. The integration of LFM and LSFM enabled the time-dependent tracking of the individual blood cells and the differential rates of segmental wall displacement during a cardiac cycle. Taken together, we demonstrated a hybrid system, coupled with our image analysis pipeline, to simultaneously capture the myocardial wall motion with intracardiac blood flow during cardiac development.

CMR for myocardial characterization in ischemic heart disease: state-of-the-art and future developments

Ischemic heart disease and its sequelae are one of the major contributors to morbidity and mortality worldwide. Over the last decades, technological developments have strengthened the role of noninvasive imaging for detection, risk stratification, and management of patients with ischemic heart disease. Cardiac magnetic resonance (CMR) imaging incorporates both functional and morphological characterization of the heart to determine presence, acuteness, and severity of ischemic heart disease by evaluating myocardial wall motion and function, the presence and extent of myocardial edema, ischemia, and scarring. Currently established clinical protocols have already demonstrated their diagnostic and prognostic value. Nevertheless, there are emerging imaging technologies that provide additional information based on advanced quantification of imaging biomarkers and improved diagnostic accuracy, therefore potentially allowing reduction or avoidance of contrast and/or stressor agents. The aim of this review is to summarize the current state of the art of CMR imaging for ischemic heart disease and to provide insights into promising future developments.

Markers of Autolysis in Acute ST Elevation Myocardial Infarction – A Comparative Analysis

Introduction: The availability of reliable noninvasive markers for infarct-related artery patency status are very limited, otherwise could allow early identification of patients with patent IRA, for whom repeat thrombolysis or rescue percutaneous coronary intervention are not necessary. Methods: We conducted a single centered retrospective study of STEMI patients undergoing primary PCI to determine how various factors such as demographic characteristics, risk markers of coronary heart disease, clinical and blood parameters present differently in patients with higher coronary flow and patent infarct related artery from patients with total occlusion at the time of initial angiography and how they affect in outcome of the disease. Results: MPV level (11.96 fL vs. 10.92 fL, P < 0.001), Lp (a) level (179.57 nmol/l vs 141.16 nmol/l , p < 0.001), CK-MB (290.2 vs. 190.98, P < 0.001), total cholesterol level (4.11 mmol/L vs. 3.8 mmol/L, p < 0.02) in total occlusion group were higher than in the patent IRA group. Wall motion abnormality was 77.2% for 203 patients with total occlusion group and 54.2% for 83 patients with patent IRA group (P<0.01). Mean hospital stay days were higher in total occlusion group as compared to the patent IRA group P < 0.01. Conclusions: MVP, Lp (a), TC, and CK-MB levels and myocardial wall motion at the presentation may play the role of markers for IRA patency status that will help in early identification of patients with IRA, for whom repeat thrombolysis or rescue PCI may not be required. Keywords: acute coronary syndrome; infarct related artery; myocardial infarction.