MUNICH, May 21, 2012 /PRNewswire/ -- SERVE-HF, the largest study to investigate if treatment of predominant central sleep apnea (CSA) improves survival and outcomes of patients with stable heart failure, has enrolled its 1,000 th participant. The study, sponsored by ResMed Ltd., is the largest of its kind. This milestone brings the SERVE-HF study, which began in 2008, one step closer to its target of approximately 1,250 participants. Principal investigator Prof. Martin Cowie, of the Royal Brompton Hospital in London said, "SERVE-HF is the world's largest study for any aspect of sleep-disordered breathing [SDB], and it has involved significant collaboration among sleep physicians, respiratory physicians and cardiologists across Europe." Co-principal investigator, Prof. Helmut Teschler, Medical Director at the Department of Pneumology, Ruhrland Clinic, Essen, added, "This study is so important because SDB in heart failure patients is a very common occurrence, particularly in men. Given that at least 50% of men with heart failure also suffer from moderate to severe SDB, treatment of SDB could be vital to improving heart failure outcomes in the future." Patients with heart failure may have an abnormal waxing and waning breathing pattern called Cheyne-Stokes respiration (CSR) with CSA. Previous studies have demonstrated that such patients have a poor quality of life as well as increased mortality, but that they may do better and live longer if they are treated with assisted ventilation during sleep. The SERVE-HF study hopes to provide more conclusive evidence of the health benefits of treating SDB in heart failure patients, and on a much larger scale. The study is being conducted at more than 80 sites in Germany, France, the UK, Norway, Sweden, Denmark, Finland, Australia and the Czech Republic. The primary goal of the study is to determine whether managing CSR-CSA with ResMed's proprietary adaptive servo-ventilation technology (found in its AutoSet CS™ and VPAP™ Adapt devices) increases survival rates and decreases the burden of hospitalizations in this patient population. Adaptive servo-ventilation is an intelligent method of non-invasive ventilation that continuously monitors and stabilizes the breathing patterns of individuals with SDB throughout the night.