BACKGROUND

Heart failure is a complex syndrome that can result from any structural or functional cardiac disorder that impairs the heart's ability to function efficiently as a pump to support physiological circulation. This project's focus is on an interventional treatment for people with heart failure caused by left ventricular systolic dysfunction, in which the left ventricle fails to pump in synchrony with some or all of the other chambers of the heart.
There are about 707,000 men and women aged 45 and over living in the UK with definite heart failure. Heart failure has a poor prognosis, with about 40% of patients dying within 1 year of diagnosis. More severely ill patients are more likely to die because of pump failure (congestive heart failure), while those with less severe heart failure are more likely to experience sudden cardiac death.

Despite numerous national and local initiatives, prognosis from heart failure continues to be relatively poor and worse than those for many cancers and the true number of annual deaths from heart failure in the UK is estimated to be at least 24,000. This means at least 4% of all deaths in the UK can be attributed to heart failure with a direct medical cost each year of over £625 million.

Recent Healthcare Commission reviews have indicated that there continues to be variation in patient outcomes and significant room for improvement in the levels of care offered to patients with heart failure.

THE TECHNOLOGY

The aim of CRT (also known as biventricular pacing) is to improve the heart's pumping efficiency by resynchronising the pumping action of the chambers. CRT involves implantation in the upper chest of a pulse generator from which three leads descend via veins into the heart. Leads are placed in the right atrium and the right ventricle, and a third lead (the left ventricular lead) is usually placed via the coronary sinus. CRT pacing (CRT-P) devices allow both regulation of atrioventricular delay and restoration of synchronous contraction by pacing the right atrium and both ventricles. A cardioverter defibrillator function can be included with the pulse generator to defibrillate the heart internally should an acute arrhythmic event occur, and in this case the device is known as a CRT-D device.

Clinical Evidence

CRT-P

Four RCTs (CARE-HF, COMPANION, MIRACLE and MUSTIC-SR) evaluate the effectiveness of CRT-P compared with optimal pharmacological therapy (OPT) alone and reported on the incidence of all-cause mortality. The three large RCTs (CARE-HF, COMPANION and MIRACLE) demonstrated a statistically significant reduction in all-cause mortality for CRT-P compared with OPT. The MUSTIC-SR trial reported no significant difference. A meta analysis of all four trials demonstrated a statistically significant reduction in all cause mortality for CRT-P compared with OPT.

CARE-HF and COMPANION reported on the rate of death from heart failure. Pooled analysis demonstrated a statistically significant reduction in death from heart failure for CRT-P compared with OPT alone

All four RCTs reported the incidence of sudden cardiac death. CARE-HF, the RCT with the longest follow-up, found a statistically significant difference between CRT-P and OPT. Meta-analysis of all four RCTs demonstrated no significant difference in the rate of sudden cardiac death for CRT-P compared with OPT.

CARE-HF, MUSTIC-SR and MIRACLE showed a statistically significant reduction in the rate of hospitalisation for CRT-P compared with OPT alone.
MIRACLE and CARE-HF found a statistically significant reduction in the risk of worsening heart failure for CRT-P compared with OPT. Three RCTs (CARE-HF, COMPANION and MIRACLE) reported statistically significant improvements in NYHA class with CRT-P compared with OPT.
All four RCTs showed consistent improvements in exercise capacity and health-related quality of life for CRT-P compared with optimal pharmacological therapy alone.

CRT-D versus optimal pharmacological therapy alone

Two RCTs (COMPANION and CONTAK-CD) evaluated the effectiveness of CRT-D compared with OPT alone. COMPANION and CONTAK-CD reported on the effect of CRT-D on all-cause mortality, which was statistically significant in one of the trials. Meta-analysis demonstrated a statistically significant reduction in all-cause mortality for CRT-D compared with OPT. COMPANION also reported improvements in the effectiveness of CRT-D compared with OPT alone for rate of death from heart failure , rate of sudden cardiac death and NYHA class COMPANION reported a significant improvement in the number of patients hospitalised due to heart failure with CRT-D. CRT-D was associated with a statistically significant reduction in the incidence of both cardiac death and sudden cardiac death compared with CRT-P.

Indications for CRT

Cardiac resynchronisation therapy with a pacing device (CRT-P) is recommended as a treatment option for people who meet all of the following criteria:

• Patients who have moderate to sever symptoms of heart failure (NYHA) class III-IV symptoms., despite lifestyle changes and optimal medication .
• People with a weakened and enlarges heart muscle (left ventricular ejection fraction of 35% or less)
• A significant electrical delay in the lower pumping chambers of the heart - QRS duration of 150 ms or longer estimated by standard electrocardiogram (ECG).

Some CRT candidates also have a high risk of Sudden Cardiac Death. For these patients, a CRT-D device can stop potentially life-threatening arrhythmias by delivering an electrical shock. This device incorporates a standard implantable cardioverter defibrillator (ICD) with a CRT pacemaker NICE published guidance on the use of CRT (TA120) in May 2007, recommending that Trusts should offer CRT to suitable patients.
http://www.nice.org.uk/Guidance/TA120/NiceGuidance/pdf/English) An implementation plan was agreed with the local PCT-based NICE Commissioning College including funding approval for increased CRT implementation but implantation rates continue to be significantly below what should be expected for various catchment populations across England.

IMPLEMENTATION PROJECT

This project is taking place at the following host NHS Trusts:

• University Hospitals Bristol NHS Trust
• Blackpool and Fylde NHS Foundation Trust
• Barnet and Chase Farm NHS Trust
• Oldham Primary Care Trust

Two mentor Trusts are working with the host Trusts to ensure successful implementation

• Liverpool Heart and Chest Hospital NHS Trust
• Southampton University Hospitals NHS Trust

Although rates of CRT device implementation have been increasing in the United Kingdom, they have generally remain lower than in Western Europe despite guidance being issued by the National Institute for Health and Clinical Excellence (NICE). Further, there is evidence of variation in the diagnosis and treatment of heart failure in women and in ethnic communities.

The cardiac resyncronisation therapy (CRT) project is a national initiative directed by the National Technology Adoption Centre (NTAC) with the purpose of improving the care of patients with heart failure through better access to fair and efficient CRT services.

The project aims to understand the barriers to adopting CRT at a local level in more detail and will share this learning in order to achieve the best possible implementation of this and other technologies.

The project is being undertaken at four healthcare organisations across England with two hospitals being nominated as mentor sites to provide advice and training to the project implementation sites.

The 4 implementation sites consist of 2 tertiary care providers , a secondary care provider and a commissioning organisation to ensure collaboration across primary, secondary and tertiary care cardiac services.

The project will investigate the local heart failure populations and current service provision in order to outline an effective, efficient and integrated model (pathway) of health care for patients with heart failure and CRT devices.

The main objective of this project is to improve CRT service provision and to capture the learning through the optimal implementation of this technology and then share this learning nationally to improve adoption of this (and other) technologies.

The benefits will include be improved access to CRT for a greater number of suitable patients, post procedure care and follow up and improved service efficiency.

Additional benefits will be an improved understanding of the barriers to technology adoption at the local level.

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