Conditions: Heart Failures
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 29
Healthy volunteers: no

Brief summary:
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.

Detailed description:

Arms:
arm 1: None arm 2: None

Interventions: intervention 1: Acetazolamide intervention 2: Placebo
Intervention descriptions: intervention 1: 4 mg/kg, once daily before bed, for 7 days intervention 2: 4 mg/kg, once daily before bed, for 7 days

Protocol document: