On fibrosis, prognosis, and the unique role of CMR: a paradigm shift from "bright is dead" to "bright is bad".

W ith an increasingly aging population, aortic stenosis (AS) has become the most frequent valvular heart disease in North America and Europe. It is a progressive condition characterized by a long latent asymptomatic period, followed by a shorter symptomatic stage associated with increased morbidity and higher mortality. Surgical aortic valve replacement (AVR) and transcatheter aortic valve replacement (TAVR) are the only effective treatments for severe AS. Currently, the timing for AVR and TAVR is based on the severity of AS, the presence of symptoms, and/or the presence of left ventricular (LV) systolic dysfunction (LV ejection fraction <50%). Asymptomatic patients tend to be treated conservatively. Nevertheless, despite these well-established criteria on the appropriateness of AVR intervention, the management of asymptomatic patients with preserved LV systolic function continues to be controversial (2). Registry data indicate that 15% of patients undergoing AVR are asymptomatic at the time of surgery (3). Novel markers to improve risk stratification would be valuable in identifying asymptomatic patients who would benefit from AVR.