Possibilities of treatment of patients with long nocturnal asystoles and obstructive sleep apnea syndrome by creating constant positive air pressure in upper respiratory tract

Aim. To study prevalence of obstructive sleep apnea syndrome (OSAS) in patients with nocturnal asystoles, and assess therapeutic efficiency of constant positive air pressure (CPAP) applied to upper respiratory tract in this category of patients. Methods. The study incorporated 37 patients (33 men and 4 women, average age 50±11 years) with nocturnal heart beat interruptions of over 3 seconds. Baseline examination revealed grade Il-III arterial hypertension in 67.5%, coronary heart disease - in 19%, diabetes mellitus in 8% and no cardiovascular disease - in 5.5% of patients. Sinus rhythm was registered in 30 (81%) of patients, 7 (19%) patients had permanent atrial fibrillation. Causes of deteriorated cardiac conduction were as follows: sinoatrial blocks and sinoatrial arrests (n=18), grade Il-III atrio-ventricular block (n=10), combination of these forms of bradyarrhythmias (n=2) and block of conduction to ventricles in permanent atrial fibrillation (n=7). According to intra-esophageal cardiac pacing, the function of sinus node and atrio-ventricular conduction appeared to be undisturbed in all patients with sinus rhythm. All patients have undergone Polysomnographic (PSG) examination. For patients with OSAS, an individual selection of therapeutic pressure was carried out using the CPAP apparatuses. CPAP therapy was considered effective against OSAS if normalization of apnea/hypopnea index (AHI) was observed. Results. OSAS was registered in 25 cases (68%) (mean AHI 54.9±28.7), 20 patients (80%) had severe grade of the syndrome. CPAP therapy appeared to be effective in all patients. At the background of treatment AHI decreased from 60.7 to 5.5 episodes per hour of sleep, mean oxygen saturation of arterial blood rose from 74 to 90%. Effect of CPAP therapy relative to cardiac conduction abnormalities was attained in all 19 patients with sinus rhythm and only in one patient with permanent atrial fibrillation. Conclusion. OSAS was revealed in 68% of patients with nocturnal bradyarrhythmias. Individually selected therapy with constant positive pressure in patients with nocturnal asystoles and OSAS efficiently eliminated in-sleep asystoles and made it possible to avoid pacemaker implantation in some patients.