Exercise Oscillatory Breathing and Sildenafil in Heart Failure

PDE5-Inhibition With Sildenafil Reverses Exercise Oscillatory Breathing in Chronic Heart Failure: a Long-Term Cardiopulmonary Exercise Testing Placebo-Controlled Study

Status

Completed

Phases

Phase 2

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT01185925

Enrollment

Registered

2010-08-20

Start date

2008-04-30

Completion date

2010-06-30

Last updated

2011-08-05

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Heart Failure

Keywords

PDE5-inhibition, exercise ventilation, heart failure, sildenafil, pulmonary hemodynamics

Brief summary

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.

Interventions

DRUGSildenafil

Sildenafil, 50 mg 3 times/day

DRUGPlacebo

Placebo

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

TRIPLE (Subject, Caregiver, Investigator)

Eligibility

Sex/Gender

MALE

Age

30 Years to 80 Years

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

Design outcomes

Primary

Measure	Time frame
Drug Effect on Oscillatory Breathing during Exercise	1 year follow-up

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026