For this week's Feature Discussion, please join authors Igor Klem, Pasquale Santangeli, Mark N.A. Estes III, and Associate Editor Victoria Delgado as they discuss, in a panel forum, the articles: " The Relationship of LVEF and Myocardial Scar to Long-Term Mortality Risk and Mode of Death in Patients with Non-Ischemic Cardiomyopathy," "Prognostic Value of Non-Ischemic Ring-Like Left Ventricular Scar in Patients with Apparently Idiopathic Non-Sustained Ventricular Arrhythmias," and "Cardiac Magnetic Resonance Imaging in Nonischemic Cardiomyopathy: Prediction Without Prevention of Sudden Death." Dr. Carolyn Lam: Welcome to Circulation on the run, your weekly podcast summary and backstage pass to the journal and its editors. We're your co-hosts. I'm Dr. Carolyn Lam, Associate editor from the National Heart Center and Duke National University of Singapore. Dr. Greg Hundley: And I'm Dr. Greg Hundley, Associate editor, Director of the Pauley Heart Center in Richmond, Virginia. Well Carolyn, this week we've got another sort of double feature with a forum and our focus is going to be on myocardial scar that's observed with late gadolinium enhancement during cardiovascular magnetic resonance and the two author groups we'll be discussing the impact of that scar on the development of ventricular arrhythmias. But before we get to that, how about we grab a cup of coffee and jump into the other articles in the issue? Would you like to go first? Dr. Carolyn Lam: I certainly would. Although I have to say, can't wait for the double feature. I love those, and this is right up your alley too. All right. But first, the first paper I want to talk about provides new randomized trial information regarding the benefits of catheter ablation in atrial fibrillation in patients who also have heart failure. Now, this is a sub-study of the CABANA trial. Dr. Greg Hundley: So Carolyn, remind us a little bit about the CABANA trial first. Dr. Carolyn Lam: I thought you might ask. Well, CABANA randomized 2,204 patients with atrial fibrillation who were 65 years or older or less than 65 with one or more risk factors for stroke at, it was huge at 126 sites, and they were randomized to ablation with pulmonary vein isolation or drug therapy. Now of these, 35% of 778 patients had New York Heart Association Class II or higher at baseline, and really formed the subject of the current paper. Although this sub-study was not specifically designed to evaluate patients with heart failure with preserved ejection fraction, about 91% of the patients with a clinical diagnosis of heart failure participating in CABANA for whom such data on injection fraction were available, really had an ejection fraction of above 40% and fully 79% had an ejection fraction above 50%. So excitingly, this is really majority talking about, have HFpEF. Now, what did they find well in patients with New York heart Association Class II or III heart failure at trial entry, most of whom did not have a reduced ejection fraction. Dr. Carolyn Lam: There was substantial clinical outcome benefits with the ablation over drug therapy with a 36% relative reduction in the primary composite endpoint of death, disabling stroke, serious bleeding or cardiac arrest. Benefits were evident for both all-cause mortality and atrial fibrillation reduction. However, the effects on heart failure hospitalization were small and not significant. Authors also caution that these results should not be viewed as practice changing until they are reproduced in a confirmatory trial of ablation in the same population. And this is beautifully discussed in an editorial by Lynda Rosenfeld and Alan Enriquez from Yale University School of Medicine. Dr. Greg Hundley: Oh, wow. Thanks Carolyn. Well, my first paper comes from the world of basic science and it's from Professor Thomas Braun, from the Max Planck Institute for Heart and Lung Research. So Carolyn, vascular smooth muscle cells show a remarkable phenotypic plasticity allowing acquisitio