Abstract
Background and study objectives: Noninvasive positive airway pressure may play a significant role in treating patients with congestive heart failure (CHF). We tested our hypothesis that noninvasive bilevel positive airway pressure improves left ventricular performance in patients with chronic CHF secondary to severe systolic dysfunction. Objectives: To determine the cardiac performance of patients using bilevel positive airway pressure, and to describe the hemodynamic effects of bilevel positive airway pressure and its use as a therapeutic adjunct in these patients. Design: Prospective, cohort, nonrandomized study. Setting: Outpatient medicine clinic. Patients: Fourteen patients (9 men and 5 women) with stable chronic CHF with left ventricular ejection fraction ≤ 35%; mean age was 60.6 years (range, 43 to 87 years). Interventions: Bilevel positive airway pressure via nasal mask at an inspiratory pressure of 5 cm H2O and an expiratory pressure of 3 cm H2O on spontaneous mode at room air for 1 h. Measurements and results: Myocardial performance and changes were measured using clinical and echocardiographic parameters. Baseline clinical and echocardiographic parameters were compared with the same parameters after 1 h of bilevel positive airway pressure. Statistically significant (p <0.05, Wilcoxon matched pair signed-rank test) decreases were noted in these mean values: systolic BP from 136.21 to 124.14 mm Hg (p = 0.008), heart rate from 85.07 to 74.71 beats/min (p = 0.002), respiratory rate from 23.07 to 15.43 breaths/min (p = 0.001), and systemic vascular resistance from 1671.46 to 1236.27 dyne · s · cm3 (p = 0.001). Statistically significant increases were noted in these mean values: cardiac output from 5.09 to 6.37 L/min (p = 0.004), ejection fraction from 28.71% to 34.36% (p = 0.001), and end-diastolic volume from 224.36 to 246.21 mL (p = 0.045). Conclusion: Bilevel positive airway pressure has excellent potential for improving left ventricular performance of patients with chronic CHF secondary to severe systolic dysfunction.