PURPOSE: The present study was designed to determine the effect of positive airway pressure (PAP) treatment of obstructive sleep apnea (OSA) on systemic blood pressure (BP) and left atrial (LA) volume.
METHODS: A retrospective review was done on patients with OSA receiving PAP who had echocardiograms (echo) pre & post polysomnography. Echo parameters, compliance to PAP & BP were assessed. Forty-seven patients were eligible for analysis. Patients were divided into two groups. Group I: compliant, using PAP > 5 nights/week and > 5 hrs/night. Group II: non-compliant not using PAP or using <5 nights/week & <5 hrs/night.
RESULTS: Group I (n=23) and Group II (n=24) showed no significant differences in AHI, BMI, BSA & BP. A decrease (mm Hg) in systolic BP of 5.3 ± 15.7 (NS), diastolic BP of 4.4 ± 8.9 (p<0.05) & MAP of 4.7 ± 10.3 (p<0.05) was seen in group I. In group II there was a decrease (mm Hg) in systolic BP of 2.1 ± 17.6 (NS), diastolic BP of 1.4 ± 12.9 (NS) and MAP of 1.6 ± 13.8 (NS). Group I patients had a decrease in left atrial (LA) volume (ml) of 3.54 ± 16.6 (n=13,NS). Group II had an average increase in LA volume of 15.47 ± 22.3 (p< 0.006). Group I, the compliant patients had a decrease in LA Index of 1.76 ± 7.37 (NS) while the non-compliant group, group II, had an increase in LA index of 6.27 ± 9.46 (p < 0.015).
CONCLUSION: Treatment of OSA was associated with a decrease in DBP & MAP in compliant patients without statistically significant change in the LA volume. The noncompliant patients had an increase in left atrial volume and index.
CLINICAL IMPLICATIONS: The increased left atrial volume may indicate an increased risk of atrial arrhythmias and LV dysfunction in inadequately treated OSA patients.
DISCLOSURE: Akram Khan, None.