Exercise Oscillatory Breathing and Sildenafil in Heart Failure

University of Milan

Status and phase: Completed; Phase 2

Conditions: Heart Failure

Treatments: Drug: Sildenafil; Drug: Placebo

Study type: Interventional

Funder types: Other

Identifiers

NCT01185925

14a

444-14

Details and patient eligibility

About

Exercise oscillatory breathing (EOB) is a ventilatory abnormality that occurs in approximately 20% of heart failure (HF) patients and carries a very unfavourable prognosis.

Pathophysiology seems quite complex and putative mechanisms include increased pulmonary capillary pressure and pulmonary vasoconstriction, circulatory blood-flow fluctuations in the pulmonary arterial system and instability of ventilatory control.

Inhibition of the phosphodiesterase 5 (PDE5) isoenzyme favourably regulates pulmonary vascular tone and permeability through over signaling of the endothelial nitric oxide pathway. The investigators tested the hypothesis that sildenafil would reverse the EOB pattern in patients with HF and pulmonary hypertension.

Enrollment: 32 patients

Sex: Male

Ages: 30 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• consent to participate in the study after detailed information about benefits and risks
• negative exercise stress test prior to study initiation
• forced expiratory volume in 1 sec/forced vital capacity ratio >70%;
• LVEF < 45%.

Exclusion criteria

• inability to complete a maximal exercise test
• resting systolic blood pressure > 140 or <110 mmHg
• therapy with nitrate preparations
• history of sildenafil intolerance
• significant lung or valvular diseases
• neuromuscular disorders or peripheral vascular disease

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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32 participants in 2 patient groups, including a placebo group

Placebo

Placebo Comparator group

Description:

Control Group

Treatment:

Drug: Placebo

sildenafil, pde5 inhibitor

Active Comparator group

Description:

treatment group; sildenafil 50 mg three times a day for 1 year

Treatment:

Drug: Sildenafil