Please assess the completion status of the following clinical trial:

Trial Title: A Study of the Effectiveness of Sitaxsentan Sodium in Patients With Diastolic Heart Failure

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: TRIPLE
- Phase: PHASE2
- Number of Arms: 2.0

Eligibility Criteria:
Inclusion Criteria:~* 18 or older with chronic heart failure and evidence of diastolic dysfunction on echocardiogram, heart imaging, and a minimum exercise tolerance average time of 120 seconds on two treadmill tests within 2 weeks of enrollment~Exclusion Criteria:~* unstable cardiovascular disease within 4 weeks of screening, history of heart attack, cardiac by-pass surgery or percutaneous intervention, stent placement, within 3 months of screening or amyloidosis, hypertrophic obstructive or restrictive cardiomyopathy, or constrictive pericarditis

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: None
- Healthy Volunteers: f

Study Arms:
- Sitaxsentan sodium (Type: EXPERIMENTAL): None
- Placebo (Type: PLACEBO_COMPARATOR): None

Based on this trial design, predict the completion outcome and termination type (if applicable).