Adherence to ASV Therapy in Heart Failure With Preserved Ejection Fraction Feasibility Study

This study is designed to demonstrate feasibility of study conduct and that acceptable adherence to adaptive servo-ventilation (ASV) therapy can be achieved in recently hospitalized HFpEF patients with moderate to severe sleep apnea. All subjects meeting the criteria will receive ASV therapy.

Cardiovascular Improvements with Minute Ventilation-targeted ASV Therapy in Heart Failure Study (CAT-HF) was a randomized controlled clinical trial in the United States and Germany. It was designed to evaluate the effect of ASV in hospitalized heart failure (HFrEF and HFpEF) patients on a global rank endpoint of survival free from CV hospitalization and improvement in functional capacity measured by 6-minute walk distance. Analysis of the 126 subjects that were randomized showed a neutral result for the primary endpoint; however, in the pre-specified analysis of the primary endpoint by LVEF strata, there was a favorable statistically significant difference in the HFpEF subgroup (p=0.036).

Although the CAT-HF study showed a positive signal in the HFpEF subgroup, these patients represented a small percentage of the randomized subjects in the study. The current study aims to show that by applying newer technologies to support adherence, as well as focusing on the lessons learned in CAT-HF to identify and recruit HFpEF patients, acceptable adherence to ASV therapy can be achieved in HFpEF patients.

Eligibility Criteria:
Inclusion Criteria:

1. Patients 18 years or older
2. Patients with heart failure with preserved ejection fraction (HFpEF; LVEF ≥50%)
3. Hospital admission or equivalent (such as ER visit alone or clinic visit alone) and acute decompensated HF as determined by:

   1. Dyspnea at rest or with minimal exertion AND
   2. Treatment with at least one dose of IV diuretic or ultrafiltration AND
   3. At least two of the following signs and symptoms:

   i. Orthopnea ii. Pulmonary rales that do not clear with cough iii. Congestion on chest X-ray iv. Local BNP or NT pro-BNP level: A. No current atrial fibrillation (AFib): BNP≥100 pg/mL or NT pro- BNP≥300 pg/mL OR B. Current AFib: BNP≥150 pg/mL or NT pro-BNP≥450 pg/mL
4. Sleep disordered breathing (SDB) documented by screening polygraphy with an AHI≥15 events/hour (e/hr)
5. Patient is able to fully understand study information and sign informed consent

Exclusion Criteria:

1. Right-sided heart failure without left-sided failure
2. Current chronic use (within 4 weeks of study entry) of any PAP therapy (eg, CPAP, APAP, or bi-level) or contraindicated for PAP therapy
3. Sustained systolic blood pressure \<80 mmHg at baseline
4. Complex congenital heart disease
5. Constrictive pericarditis
6. Chronic hypoxemia as evidenced by sustained oxygen saturation ≤ 85% at rest during the day or at start of nocturnal oximetry recording or regular use of oxygen therapy (day or night)
7. Transient ischemic attack (TIA) or Stroke within 3 months prior to study entry
8. Definite clinically evident acute myocardial infarction within 3 months of study entry
9. Known amyloidosis, hypertrophic obstructive cardiomyopathy, or arteriovenous fistulas
10. Moderate or greater valvular heart disease as the primary reason for heart failure
11. Pregnant, or planning to become pregnant during the study period
12. In the opinion of the investigator, the index acute decompensated HF event was due primarily to uncontrolled AFib with fast ventricular response rate
13. Inability to comply with planned study procedures