This week's episode features author Torbjørn Omland and Senior Guest Editor Vera Bittner as they discuss the artile "Growth Differentiation Factor-15 Provides Prognostic Information Superior to Established Cardiovascular and Inflammatory Biomarkers in Unselected Patients Hospitalized with COVID-19." TRANSCRIPT BELOW: Dr. Carolyn Lam: Welcome to Circulation on the Run, your weekly podcast summary, and backstage pass to the journal and its editors. We are your co-hosts, I'm Dr. Carolyn Lam, associate editor from the National Heart Center and Duke National University of Singapore. Dr. Greg Hundley: I'm Dr. Greg Hundley, Director of the Pauley Heart Center at VCU Health in Richmond, Virginia. Well, Carolyn our feature this week gets into inflammatory biomarkers in patients that have been hospitalized with COVID-19, but before we get to that, how about we grab a cup of coffee and work through some of the papers in the issue. Would you like to go first? Dr. Carolyn Lam: Absolutely. With both the coffee and the papers. So great, for this first paper, have you thought about concentric versus eccentric cardiac hypertrophy? We traditionally associate them with pressure versus volume overload respectively in cardiovascular disease, both though conferring an increased risk of heart failure. These contrasting forms of hypertrophy are characterized by asymmetric growth of the cardiac myocytes in mainly width or length respectively. However, the molecular mechanisms determining myocyte preferential growth in width versus length remain poorly understood. Dr. Carolyn Lam: That is until today's paper, and it is from Dr. Kapiloff from Stanford University, and Dr. Rosenfeld from UCSD, School of Medicine and their colleagues, and what they did was used primary adult rat ventricular myocytes, as well as Adeno associated virus mediated gene delivery in mice, to define a regulatory pathway controlling pathological myocyte hypertrophy, and they found that asymmetric cardiac myocyte hypertrophy is modulated by serum response factor phosphorylation, constituting an epigenomic switch balancing the growth in width versus length of adult ventricular myocytes In vitro, and In vivo. Dr. Carolyn Lam: Serum response factor phosphorylation was bi-directionally regulated at signalosomes organized by the scaffold protein muscle, A kinase anchoring protein beta. This newly identified molecular switch controlled a transcriptional program responsible for modulating changes in cardiomyocyte morphology that occurs secondary to pathological stressors. Dr. Greg Hundley: Very nice, Carolyn. So switches controlling this transcriptional program. Tell us a little bit, and bring us back to the clinical relevance of this and starting with that concentric versus eccentric hypertrophy? Dr. Carolyn Lam: I thought you may ask. The identification of a molecular mechanism regulating that asymmetric cardiomyocyte growth, really provides a new target for the inhibition of pathological cardiac hypertrophy. Studies in mice using these Adeno associated virus based gene therapies to modulate that signalosome, really provided proof of concept for translational potential in the treatment of pathological cardiac remodeling and prevention of heart failure. Dr. Greg Hundley: Oh, wow. Very nice, Carolyn. Well, my first paper comes to us from Professor Dirk Westermann from Hamburg, and focuses on cardiogenic shock patients, and veno-arterial ECMO, the results from the international multicenter cohort study. So Carolyn this study evaluated data from 686 consecutive patients with cardiogenic shock treated with VA ECMO with or without left ventricular unloading using an Impella, and they conducted this at 16 tertiary care centers across four countries. They examined the association between left ventricular unloading and 30 day mortality. Dr. Carolyn Lam: Huh, so what did they find? Dr. Greg Hundley: Okay. Carolyn. Well, left ventricular unloading was used in 337 of the 686 patients enrolled, and a