Clonidine to Prevent Implantable Cardiovertor Defibrillator Firing

James Martins

Status: Withdrawn

Conditions: Ventricular Tachycardia

Treatments: Drug: metoprolol; Drug: clonidine

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT00585871

200602703

study is over no ID is needed

Details and patient eligibility

About

Cardiac arrest or sustained VT (ventricular tachycardia) in patients with heart disease is best treated with an ICD (implantable cardioverter defibrillator). However, the ICD alone is not appropriate therapy for patients with frequent VT episodes. In fact frequent shocks for VT may predict a poorer prognosis. Anti-arrhythmic drugs are co-administered with ICDs in up to 50% of patients to prevent VT episodes, but antiarrhythmic drugs may have harmful effects. Thus improved drugs to prevent VT without interfering with ICD function are needed. Recent data including our own suggest that clonidine may be a new therapy to prevent ICD shocks. It may act centrally on sympathetic outflow and peripherally and selectively on cardiac Purkinje, to suppress and control VT occurring in patients. Our purpose is to test the hypothesis that clonidine reduces frequent VT better than beta blocker in patients with ICDs. After informed consent patients will be randomized in a single blind fashion to either clonidine or metoprolol given three times per day. Other prescribed drugs may be adjusted to promote toleration of the study drug. ICD interrogations of episodes of VT will be the primary endpoint. Device based NIPS (non-invasive programmed stimulation) testing in a subset of these patients will allow mechanistic understanding of the clonidine effect. All of the procedural techniques are in place as performed clinically; preliminary data are given showing feasibility of the project.

Full description

we had wanted very commonly occurring VT episodes on ICD interrogation: 5 episodes/ 3 months. We could not enroll more than 2 patients most of which have interventions to prevent episodes. Thus we could not enroll patients and discontinued the study in the first year.

Sex: All

Ages: 18 to 85 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Implantable defibrillator treated patients with 5 episodes of ventricular tachycardia per 3 month period

Exclusion criteria

• No more than one shock/3 months
• No contraindication to clonidine
• Non-compliance
• Asthma

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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0 participants in 2 patient groups

Clonidine therapy group

Experimental group

Description:

clonidine 0.1 TID

Treatment:

Drug: clonidine

Metoprolol control group

Active Comparator group

Description:

metoprolol 25 TID

Treatment:

Drug: metoprolol