Predicting Successful Sleep Apnea Treatment With Acetazolamide in Heart Failure Patients

Physiological Study to Predict Successful Sleep Apnea Treatment With Acetazolamide in Heart Failure Patients

The ultimate goal is to improve our understanding of the pathophysiology and resistance to effective treatment of sleep disordered breathing in patients with heart failure, with a focus on selecting patients that will benefit specifically from acetazolamide treatment.

The study addresses three primary hypotheses: 1) Acetazolamide treatment will reduce the apnea-hypopnea index and improve markers of heart-failure severity in heart-failure patients with sleep apnea. 2) Acetazolamide will provide the greatest improvement in patients with the most severe ventilatory control instability (strongest chemoreflex response to carbon dioxide; highest loop gain). 3) Acetazolamide will act primarily via stabilizing ventilatory control (reducing loop gain), rather than via improvement to upper airway anatomy, pulmonary congestion, and cardiac function.

Inclusion Criteria (Heart failure patients)

• Left ventricular ejection fraction (EF) <50%, or heart failure with preserved EF
• Age 18-89

Exclusion Criteria:

• severe obstructive respiratory disease
• unstable heart failure status
• recent use of positive airway pressure therapy
• current use of opioids, benzodiazepines
• severe kidney disease
• severe anemia