Sleep related breathing disorders and effects of adaptive servo-ventilation in patients with heart failure

Sleep related breathing disorders as obstructive apnea, central apnea and cheyne-stokes respiration (CSR) can be seen in patients with chronic heart failure. These sleep related disorders can influence prognosis in heart failure patients.Aim of the study, was to investigate sleep related breathing disorders in patients with heart failure and to display the effects of adaptive servo-ventilation (ASV) as a new therapy modality on these respiratory disorders. In this prospective study, between February 2011 ? July 2012, 32 patients with heart failure from Cardiology and Pulmonology outpatient clinics of Gaziantep University Hospital were included. One night polysomnography (PSG) was done. According to the results of PSG, sleep related breathing disorders ratio was 96.7% in our patients. 90% of these were obstructive sleep apnea syndrome (OSAS), 6.7% central apnea syndrome and only 3.3% was normal. Continuous positive airway pressure (CPAP) and adaptive servo-ventilation (ASV) applications were offered to all patients with apnea-hypopnea index (AHI) > 5, each one in different night and 3 days between the two modality. Demographics and clinical properties, symptoms, sleep efficiency, apnea-hypopnea indexes, distribution of respiratory events, minimum SpO2 measurements, presence of CSR, echocardiography results were recorded. Before and after ASV titration, pulmonary function tests, 6 minutes walking tests were performed, concentrations of transferrin and pro-BNP were determined. In the groups we determine severe OSAS in 18 of 30 patients, 4 moderate OSAS, 5 mild OSAS and 2 central sleep apnea (CSA). One patient was assessed as normal (AHI<5). PSG and CPAP, ASV titrations done in 7 male and 1 female patients that obstructive apnea, central apnea, AHI, arousal and SpO2 min values had significant improvements (p=0,001 p=0,016 p=0,001 p=0,015 p=0,008 respectively). All CSRs were eliminated with ASV. In eight patients, after ASV titration pro-BNP, walking distance and FVC values changed significantly (in order p=0,036 p=0,018 p=0,018).As a result, we determined CSR and central apneas persisted with CPAP but eliminated with one-night ASV application. One night ASV application decreased serum values of pro-BNP and increased FVC and 6 minutes walking distance values significantly. ASV supressed obstructive apneas and AHI more than CPAP but there were no significant difference.Keywords: Central apnea syndrome, Heart Failure, Pro-BNP, Adaptive servo-ventilation (ASV), Cheyne-Stokes respiration (CSR).