In This Issue of the Journal.

Abstract

January 2021 2 Robert J. Gropler , MD Editor in Chief, Circulation: Cardiovascular Imaging O n behalf of the entire Editorial Team at Circulation: Cardiovascular Imaging, I want to wish you a happy New Year and welcome you to our January 2021 issue of the journal. We provide a host of offerings that highlight advances in cardiovascular imaging to improve disease risk stratification in various cardiovascular diseases, enhance our understanding of coronavirus disease 2019 (COVID-19)–induced myocardial injury, and provide important perspectives on the ISCHEMIA trial (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches). In patients with heart failure and reduced ejection fraction, left atrial enlargement and poor left atrial function assessed with a variety of indices such as phasic volume changes or strain-based measurements of reservoir, conduit, and booster pump function, are associated with poorer prognosis. Benfari et al add to this repertoire by reporting in patients with heart failure and reduced ejection fraction that the echocardiographically measured left atrial volumetric/mechanical coupling index is associated with higher grades of functional mitral regurgitation and is independently associated with mortality. In their editorial, Vidula and Chirinos clearly describe the physiological relevance of this measurement and where it may be the most useful in evaluation of the heart failure patient. In COVID-19 patients, elevated troponin levels, indicating myocardial injury, are frequently observed and are associated with adverse outcomes. The etiology of the myocardial injury is not clear, but it appears myocardial inflammation is a key contributor. Weckbach and colleagues assessed a small cohort of COVID-19 patients with elevated troponin levels using transthoracic echocardiography, cardiac magnetic resonance imaging, and endomyocardial biopsy and report myocardial injury was associated with reduced by left ventricular strain, myocarditis patterns, and a macrophage (not lymphocytic)-dominated myocarditis, respectively. In their commentary, Verma and Vader concisely summarize our current understanding of COVID-19–induced myocardial injury and the strengths and weaknesses of the current study, as well as identify the logical next investigational steps. An Agatston coronary artery calcium (CAC) score of zero is well established as a biomarker of low cardiovascular risk. However, it is increasingly being recognized that the accurate detection of low levels of CAC are susceptible to slice thickness and thresholding effects. To help address this concern, Shea et al provide evidence that in patients with an Agatston CAC score of zero, a spatially weighted CAC score can provide further risk stratification and progression to the development of CAC. In their editorial, Bittencourt and Nasir nicely position the study findings with respect to current literature and raise the important question of the clinical importance of further risk stratification of this already low-risk patient population. Given the marked prognostic variability in patients with heart failure and reduced ejection fraction, there continues to be great interest in identifying biomarkers that © 2021 American Heart Association, Inc. EDITOR’S NOTE