Cardiac Resynchronization Therapy, Dyspnea and Exercise Tolerance in Patients With Congestive Heart Failure (CHF)

Queen's University

Status and phase: Terminated; Phase 4

Conditions: Congestive Heart Failure

Treatments: Device: Active Cardiac Resynchronization Therapy (CRT)

Study type: Interventional

Funder types: Other

Identifiers

NCT00700700

DMED-1082-07

Details and patient eligibility

About

A new therapy for patients with advanced heart failure (HF) involves the implantation of a specialized pacemaker device (Cardiac Resynchronization Therapy, CRT) that attempts to restore the synchronized contraction of the ventricular chambers of the heart. In some people, CRT improves exertional breathlessness and allows them to exercise for longer periods. However, to date, the mechanisms by which CRT improves symptoms and exercise tolerance is unknown. This study will use in-depth cardiopulmonary exercise testing and pulmonary function testing to explore these mechanisms in greater detail.

Enrollment: 2 patients

Sex: All

Ages: 18 to 90 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• clinically stable
• being considered for implantation of biventricular pacemaker for CRT
• LVEF <35%
• QRS duration >120 msec
• NYHA III-IV functional class
• optimized pharmacologic management of CHF
• no recent (<1 month) episodes of decompensated CHF

Exclusion criteria

• inability to perform cycle ergometry or comply with testing
• uncontrolled ischemic heart disease
• coronary revascularization within 3 months of study entry
• concurrent primary lung disease
• current use of ambulatory oxygen
• rhythm other than sinus
• dependency on pacemaker therapy as a consequence of bradyarrhythmias
• severe valvulopathy

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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2 participants in 2 patient groups

CRT-ON/CRT-OFF

Active Comparator group

Description:

Group initially randomized to CRT-ON, then cross-over to CRT-OFF

Treatment:

Device: Active Cardiac Resynchronization Therapy (CRT)

CRT-OFF/CRT-ON

Active Comparator group

Description:

Group initially randomized to CRT-OFF, then cross-over to CRT-ON

Treatment:

Device: Active Cardiac Resynchronization Therapy (CRT)