Acetazolamide and Inhaled Carbon Dioxide Reduce Periodic Breathing During Exercise in Patients With Chronic Heart Failure

作者：Apostolo Anna; Agostoni Piergiuseppe^*; Content Mauro; Antonioli Laura; Swenson Erik R

来源：Journal of Cardiac Failure, 2014, 20(4): 278-288.

DOI：10.1016/j.cardfail.2014.01.007

• Oscillatory ventilation
• cardiopulmonary exercise test
• polysomnography

Background: Periodic breathing (PB) during sleep and exercise in heart failure (HF) is related to respiratory acid-base status, CO2 chemosensitivity, and temporal dynamics of CO2 and O-2 sensing. We studied inhaled CO2 and acetazolamide to alter these factors and reduce PB.
Methods and Results: We measured expired and arterial gases and PB amplitude and duration in 20 HF patients during exercise before and after acetazolamide given acutely (500 mg intravenously) and prolonged (24 hours, 2 g orally), and we performed overnight polysomnography. We studied CO2 inhalation (1%-2%) during constant workload exercise. PB disappeared in 19/20 and 2/7 patients during 2% and 1% CO2. No changes in cardiorespiratory parameters were observed after acute acetazolamide. With prolonged acetazolamide at rest: ventilation +2.04 +/- 4.0 L/min (P = .001), tidal volume +0.11 +/- 1.13 L (P = .003), respiratory rate +1.24 +/- 4.63 breaths/min (NS), end-tidal PO2 +4.62 +/- 2.43 nun Hg (P = .001), and end-tidal PCO2 -2.59 +/- 9.7 mm Hg (P < .001). At maximum exercise: Watts -10% (P < .02), VO2 -61 +/- 109 mL/min (P = .04) and VCO2 101 +/- 151 mL/min (P < .02). Among 20 patients, PB disappeared in 1 and 7 subjects after acute and prolonged acetazolamide, respectively. PB was present 80% +/- 26, 65% +/- 28, and 43% +/- 39 of exercise time before and after acute and prolonged acetazolamide, respectively. Overnight apnea/hypopnea index decreased from 30.8 +/- 83.8 to 21.1 +/- 16.9 (P = .003).
Conclusions: In HF, inhaled CO2 and acetazolamide reduce exercise PB with additional benefits of acetazolamide on sleep PB.

• 出版日期2014-4