PROJECT ABSTRACT OF ADMINISTRATIVE EXTENSION We propose to build on the existing infrastructure of the University of Southern California (USC) and Saint Luke’s Mid America Heart Institute in Kansas City (MAHI) Linked Clinical Research Center to perform a series of analyses to better understand the health status outcomes after mitral valve surgery. The two treatment goals of mitral valve surgery are to prolong survival and improve patients’ symptoms, function, and quality of life. Despite the frequency of mitral valve surgery and its intended treatment benefits, little is known about the health status outcomes of patients who undergo valve surgery. There have been 3 trials involving mitral valve surgery conducted by the CTSN in which longitudinal disease-specific health status were collected. This proposed project will leverage the CT surgical expertise at USC and the methodological expertise in health status assessment at MAHI to assemble a team uniquely positioned to answer important questions about health status after mitral surgery. The specific aims of this administrative extension are to (1) leverage the data collected by the CTSN as a part of 3 multicenter clinical trials to expand our understanding of the trajectories of health status improvement after mitral valve surgery; 2) identify the patient factors that are associated with health status improvement (or lack of improvement) after mitral valve surgery, to better define the heterogeneity treatment benefit based on patient demographic and clinical factors; 3) explore the impact of post-operative atrial fibrillation—the most common complication of surgery—to health status recovery; and 4) examine the impact of less common surgical complications on the long-term health status of patients. The cardiothoracic surgical team at USC will provide critical guidance on the clinical aspects of surgery, important complications, and expected recovery. The cardiology and statistical team at MAHI will primarily construct the analytic plans and execute the analyses. This team has decades of experience in analyzing disease-specific health status measures in all forms of cardiac conditions, with Dr. Arnold having specific expertise in the health status of patients with valve disease undergoing interventions. The CTSN team will also provide methodological insight on the analysis of health status around the time of valve surgery and will be responsible for collating and harmonizing the data across the 3 trials. The results from these analyses are expected to greatly enrich the shared decision-making process prior to surgery, providing key insights about improvement in symptoms, function, and quality of life based on individual patient factors and the potential impact that complications may have on this recovery.