To assess the acute effects of oxygen (O2), continuous positive airway pressure (CPAP) and noninvasive positive pressure ventilation (NIPPV) on sleep apnea (SA) in stable congestive heart failure (CHF).
The subjects were 11 patients (pts) with stable CHF (6; dilated cardiomyopathy, 4; old myocardial infarction, 1; valvular disease). These pts were examined with SpO2, nasal air flow sensor, chest wall and abdominal motion and ECG monitoring system (Morpheus C; Teijin), urinary noradrenaline concentration and next morning mood index during sleep at night under room air (Control), O2, CPAP and NIPPV.
Although 9 pts completed all 4 studies, 2 pts completed only Control and O2 study. Apnea hypopnea index (AHI; /hr) improved from 24±10 (mean±SD) in Control to 18±10 with O2, 15±11 with CPAP and 11±10 with NIPPV. Central apnea index (CAI; /hr) improved from 9±9 in Control to 5±7 with O2, 7±8 with CPAP and 2±2 with NIPPV. In 4 pts with CAI≥15, CAI improved most with NIPPV but not so effective with CPAP (from 20±4 in Control to 12±9 with O2, 14±7 with CPAP and 3±1 with NIPPV). In 5 pts with CAI<15, CPAP also improved CAI (3±3, 1±1, 0.6±1 and 0.1±0.3, Control, O2, CPAP and NIPPV, respectively). Ventricular ectopic beats decreased 1,000±1,176 in Control to 432±513 with NIPPV in pts with CAI≥15, but in pts with CAI<15 CPAP was the most effective (810±1,788 in Control to 167±345 with CPAP). No significant difference was seen in urinary noradrenaline concentration and next morning mood index.CONCLUSIONS: O2, CPAP and NIPPV are effective in improving SA, and NIPPV is the most effective in pts with stable CHF and dominance of central SA. CPAP is effective in pts with CHF and dominance of obstructive SA.
O2, CPAP and NIPPV are useful methods for improving SA, and might be useful complementary therapies for treating stable CHF .
H. Koito, None.