Influence of continuous positive airway pressure (CPAP) on the left ventricular function, in patients with obstructive sleep apnoea syndrom (OSAS)
Ryszarda Chazan, Maria Jakubowska-Najniger, Elżbieta Chazan-Polanowska, Tadeusz Przybyłowski, Danuta Liszewska-Pfeifer, Wacław Droszcz
Med Sci Monit 1998; 4(2): CR250-254
The aim of this study was to evaluate left ventricular function in patients with OSAS and arterial hypertension following the use of n-CPAP. Twenty-two patients with (OSAS) obstructive sleep apnoea syndrome were divided into two groups: one group comprised patients with OSAS and without arterial hypertension, the other, patients with OSAS and hypertension. The influence of CPAP (continuous positive airway pressure) on left ventricular function was evaluated using 2D and Doppler echocardiography. The systolic left ventricular function (ejection fraction) was normal in all patients. At the beginning of this study both groups demonstrated a decrease in peak mitral flow velocity during early diastole E (m/sec), an increase of atrio-systolic contraction A (m/sec), an increase in E/A and a prolonged isovolemic relaxation time (IVRT). After three months treatment with CPAP, an increase in the E/A, ratio of 1.38±0.23m/sec vs 0.98±0.28 (p<0.05) and a reduction in IVRT, of 79.0±6.8msec vs 91.3±6.3 (p<0.05) in the second group (patients with OSAS and hypertension) could be seen. In the first group (patients with OSAS and without hypertension) we only observed a statistically significant reduction in IVRT, 77.8±5.4 vs 83.7±5.15 msec p<0.05.
Keywords: CPAP (continuous positive airway pressure), OSAS (obstructive sleep apnoea syndrome), Echocardiography