Effects of Viagra on Heart Function in Patients With Heart Failure

NCT ID: NCT00781508

Last Updated: 2014-07-02

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE4
• Total Enrollment: 10 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2006-12-31
• Study Completion Date: 2009-11-30

Brief Summary

Sildenafil (Viagra) is known to reduce pulmonary hypertension. Heart failure patients also have pulmonary hypertension and several recent reports have shown that sildenafil leads to an improvement in their exercise capacity. In these studies sildenafil caused a reduction in the pulmonary and systemic vascular resistances, improved pulmonary gas diffusion and perhaps increased cardiac output. It is uncertain if left ventricular filling pressures are reduced and whether there is improvement in left ventricular relaxation. The investigators hypothesize that in heart failure patients the improvement in exercise capacity associated with sildenafil is related to a significant reduction in left ventricular filling pressures. The investigators propose to study 20 patients with stable but moderately symptomatic heart failure. The study design is a randomized cross-over trial of the administration of a single dose of sildenafil 50 mg or a matching placebo. Exercise capacity will be determined before and after the oral administration of sildenafil 50 mg or placebo. Left ventricular filling pressures will be assessed by Doppler echocardiography and the serum level of B-type natriuretic peptide (BNP is known to increase with higher left ventricular filling pressures). After an initial echocardiogram and performing a 6 minute walk test, the patient will then be given either sildenafil or a matching placebo in a randomized double-blind fashion. One hr later a blood sample for serum BNP, the echocardiogram and the 6 minute walk test will be repeated.

Detailed Description

Sildenafil (Viagra) has been extensively studied in patients with idiopathic pulmonary hypertension. It reduces pulmonary vascular resistance, improves exercise capacity and is now an approved therapy for this condition. Heart failure (HF) patients also have pulmonary hypertension and several recent reports have shown that sildenafil leads to an improvement in their exercise capacity. In HF sildenafil causes a reduction in the pulmonary and systemic vascular resistances, improves pulmonary gas diffusion and perhaps increases cardiac output. It is uncertain if left ventricular filling pressures are reduced and whether there is improvement in left ventricular relaxation. We hypothesize that in HF patients the improvement in exercise capacity associated with sildenafil is related to a significant reduction in left ventricular filling pressures. We propose to study 10 patients with stable, symptomatic HF Class III. The study design is a randomized cross-over assignment of the administration of a single oral dose of sildenafil 50 mg or a matching placebo. Patients will be excluded if walking is impaired due to non-cardiac conditions or if they are taking nitrates. Exercise capacity will be determined before and 60 minutes after the oral administration of sildenafil 50 mg or placebo. The difference in the standardized 6 minute walk test (distance patient is able to walk over a 6 minute interval) will be used to assess exercise capacity. Left ventricular filling pressures will be assessed by Doppler echocardiography and the serum level of B-type natriuretic peptide (BNP). Evaluation of left ventricular relaxation will be determined by Doppler echocardiography techniques. Each patient will have a blood sample for BNP, an initial echocardiogram and perform a 6 minute walk test. They will then be given a single dose of either sildenafil or a matching placebo in a randomized double-blind fashion. The randomization was performed so that half of the group would receive the placebo on the initial test and sildenafil on the subsequent test and the other half would have the reverse sequence. One hr after the medication/placebo administration a blood sample for serum BNP, the echocardiogram and the 6 minute walk test will be repeated. After completion of the above protocol, the patient will return in 48 hrs and the protocol will be repeated with the predetermined assignment of either placebo or sildenafil.

Conditions

Heart Failure; Left Ventricular Dysfunction

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

sildenafil

Effect of oral administration of a single dose of sildenafil 50 mg on left ventricular filling pressures as evaluated 1 hr after sildenafil administration in patients with heart failure

Group Type: EXPERIMENTAL

sildenafil

Intervention Type: DRUG

Changes in left ventricular filling pressure 1 hour after the administration of a single oral dose of sildenafil 50 mg.

Placebo

Intervention Type: OTHER

Changes in left ventricular filling pressure 1 hour after oral administration of placebo

placebo

Inactive placebo prepared to mimic the appearance of sildenafil.

Group Type: PLACEBO_COMPARATOR

sildenafil

Intervention Type: DRUG

Changes in left ventricular filling pressure 1 hour after the administration of a single oral dose of sildenafil 50 mg.

Placebo

Intervention Type: OTHER

Changes in left ventricular filling pressure 1 hour after oral administration of placebo

Interventions

sildenafil

Changes in left ventricular filling pressure 1 hour after the administration of a single oral dose of sildenafil 50 mg.

Intervention Type: DRUG

Placebo

Changes in left ventricular filling pressure 1 hour after oral administration of placebo

Intervention Type: OTHER

Other Intervention Names

Viagra

Eligibility Criteria

Inclusion Criteria

• Adults with Class III congestive heart failure and impaired left ventricular systolic function.
• A prior BNP level ≥ 200 pg/mL.
• Previously documented systolic pulmonary artery pressure >40 mmHg.
• Clinically stable for a minimum of 6 weeks.
• Able to give informed consent,

Exclusion Criteria

• Unable to give informed consent.
• Currently taking nitrates.
• A HF exacerbation within the past 6 weeks.
• Co-morbid conditions that could limit their walking.
• Have a resting systolic blood pressure < 110 mmHg

• Minimum Eligible Age: 25 Years
• Maximum Eligible Age: 75 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

National Center for Research Resources (NCRR)

NIH

Sponsor Role: collaborator

MetroHealth Medical Center

OTHER

Sponsor Role: lead

Responsible Party

Robert Bahler

Cardiologist Professor of Medicine CWRU

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Robert C Bahler, MD

Role: PRINCIPAL_INVESTIGATOR

MetroHealth Medical Center

Locations

MetroHealth Medical Center

Cleveland, Ohio, United States

Countries

United States

Other Identifiers

Grant Number UL1 RR024989

Identifier Type: OTHER_GRANT

Identifier Source: secondary_id

ULI RR024989

Identifier Type: OTHER_GRANT

Identifier Source: secondary_id

MO1RR000080

Identifier Type: -

Identifier Source: org_study_id