Cardiac Resynchronisation Study

A Study of the Effect of Cardiac Resynchronisation Therapy (CRT) on Chemosensitivity in Patients With Chronic Heart Failure With and Without Sleep Disordered Breathing.

This study aims to investigate the effect of a pacemaker device used in heart failure patients which is called Cardiac Resynchronisation Therapy (CRT). Specifically the investigators aim to investigate if the CRT pacemaker has an effect on breathing stability in these patients and particularly breathing stability at night. Our theory is that the CRT pacemaker may improve the stability of breathing in patients with heart failure.

Study Overview

• Status: Completed
• Conditions: Heart Failure

Detailed Description

AIM To investigate the effect of Cardiac Resynchronisation Therapy (CRT) on chemosensitivity in patients with Chronic Heart Failure with and without Sleep Disordered Breathing (SDB).

OBJECTIVE To conduct a physiological observational study to measure hypercapnic ventilatory responses in a group of CHF patients before and 3 months after implantation of clinically indicated CRT devices. Additionally to conduct nocturnal polysomnography to establish if any change in chemosensitivity is related to the presence of SDB at baseline and, where present, any change in SDB after implantation.

HYPOTHESIS Primary hypothesis: CRT implantation will be associated with a reduction in the hypercapnic ventilatory response from baseline to 3 months post implantation.

Additional hypothesis: This reduction in hypercapnic ventilatory response after CRT implantation will be greatest in those CHF patients with SDB at baseline.

• Study Type: Observational
• Enrollment (Actual): 182

Contacts and Locations

Study Locations

• United Kingdom
  • London, United Kingdom, SW3 6NP
    • Royal Brompton Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Patients with Chronic Heart Failure who fulfil the current national guidelines for CRT insertion (see inclusion criteria)

Description

Inclusion Criteria:

1. Age ≥18 years old
2. Fulfil the current guidance for the implantation of a CRT device; optimal medical treatment for heart failure, broad QRS complex on electrocardiogram with or without evidence of cardiac dyssynchrony as appropriate, LVEF <35%, functional impairment as defined by an NYHA class of III-IV
3. Clinically stable with no unplanned admission to hospital for preceding 4 weeks
4. No changes in medications for heart failure in preceding 4 weeks
5. Able to read and understand patient information sheet and give informed consent

Exclusion Criteria:

1. On positive pressure treatment for known sleep disordered breathing at the time of inclusion
2. Other known condition (untreated) likely to significantly disturb sleep eg. Restless legs syndrome, pain from any cause etc.
3. Pregnancy

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Patients undergoing clinically indicated CRT implantation; Patients may be included in the study if they fulfil the following; Age ≥18 years old; Fulfil the current guidance for the implantation of a CRT device; optimal medical treatment for heart failure, broad QRS complex on electrocardiogram with or without evidence of cardiac dyssynchrony as appropriate, LVEF <35%, functional impairment as defined by an NYHA class of III-IV; Clinically stable with no unplanned admission to hospital for preceding 4 weeks; No changes in medications for heart failure in preceding 4 weeks; Able to read and understand patient information sheet and give informed consent Patients must be excluded from the study if they fulfil they the following; On positive pressure treatment for known sleep disordered breathing at the time of inclusion; Other known condition (untreated) likely to significantly disturb sleep eg. Restless legs syndrome, pain from any cause etc.; Pregnancy

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in chemosensitivity before and after CRT implantation	We will look primarily at the effect of CRT implantation on chemosensitity which we will measure using the ventilatory sensitivity to carbon dioxide.	3 months

Collaborators and Investigators

• Sponsor: Imperial College London

Publications and helpful links

Helpful Links

• National Institute of Clinical Excellence; technology appraisal about CRT devices

Study record dates

Study Major Dates

• Study Start: October 1, 2010
• Primary Completion (Actual): October 1, 2011
• Study Completion (Actual): October 1, 2011

Study Registration Dates

• First Submitted: October 1, 2010
• First Submitted That Met QC Criteria: October 1, 2010
• First Posted (Estimate): October 4, 2010

Study Record Updates

• Last Update Posted (Estimate): October 22, 2015
• Last Update Submitted That Met QC Criteria: October 21, 2015
• Last Verified: October 1, 2015

More Information

Terms related to this study

• Keywords: Heart failure
• Additional Relevant MeSH Terms: Heart Diseases; Cardiovascular Diseases; Heart Failure
• Other Study ID Numbers: 10/H0706/5