Authors' objectives:

This study aims to assess the effectiveness or cost effectiveness of biventricular (BiV) pacemakers in patients with severe chronic heart failure (HF).

Authors' results and conclusions: Randomized controlled trials [Level 1 evidence]assessed chronic heart failure patients for up to six months. The trials reported improved cardiac function and quality of life up to 6 months of BiV pacemaker treatment. Therefore there is some evidence that patients in ventricular dyssynchrony, and who are still symptomatic after medication may benefit from this technology. There is no evidence regarding the long term efficacy or safety of this device. Some studies have evaluated single left ventricular pacing for patients with severe, chronic HF and ventricular dyssynchrony. The benefit of BiV versus single left ventricular pacing for HF is unknown. BiV pacing is the predominant mode of pacing being studied. One study failed to demonstrate any advantage for BiV over single left ventricular pacing. Implantation and maintenance of a resynchronization device are associated with risks that are greater than those of a conventional pacing device. There is insufficient evidence to support the routine use of combined BiV/ICD devices in patients with chronic HF. Much uncertainty still exists in BiV pacing : - There are a small number of completed trials evaluating BiV pacing in chronic HF patients. - It is not known if BiV pacing reduces symptoms or outcomes in patients 3-9 months after first diagnosis of HF. - The length of follow-up has been of a short duration. - Long-term benefits and effects on mortality are unknown. - Inability to identify patients who will not improve clinically following resynchronization therapy. - Soft subjective nature of many of the endpoints (symptoms, exercise capacity, quality of life); paucity of harder endpoints (mortality, implant success, lead complication rates). - Lack of economic analyses. - The role of the combination BiV and implantable cardioverter defibrillator (ICD) device in HF patients. For both of these devices, implantation procedures are more complex than either the implantation of traditional pacemakers or ICDs alone. These devices would need to be implanted in select centres to maintain adequate patient volumes as well as further refine the surgical technique as the technology evolves.

Authors' recommendations: There is sufficient evidence of short-term effectiveness for BiV in patients with chronic severe HF, ventricular dyssynchrony, and refractory to exhaustive drug therapy. Currently, due to limited follow-up in studies evaluating BiV pacemakers, there is insufficient evidence to confirm the long-term (>6 months) safety, effectiveness and cost-effectiveness of this device in the treatment of patients with chronic severe HF. To date, there is insufficient evidence to support the routine use of combined ICD/BiV devices in patients with chronic severe HF. Several large randomized studies are being carried out or have recently been completed which should provide new evidence. The results of this assessment will need to be updated once results from these trials have been fully reported.

Authors' methods: Systematic review

Project Status: Completed

URL for project: http://www.health.gov.on.ca/english/providers/program/mas/tech/techlist_ mn.html

Year Published: 2004

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: Canada

Organisation Name: Medical Advisory Secretariat

Contact Address: Medical Advisory Secretariat, 20 Dundas Street West, 10th Floor, Toronto, ON M5G 2N6 CANADA. Tel: 416-314-1092l; Fax: 416-325-2364;

Contact Name: MASinfo.moh@ontario.ca

Contact Email: MASinfo.moh@ontario.ca

Copyright: Medical Advisory Secretariat, Ontario Ministry of Health and Long-Term Care