Cardiac pumps in treating chronic heart failure

Findings by SBU Alert

Version: 4

Technology and target group

Chronic heart failure can be treated mechanically with cardiac pumps (left ventricular assist device, LVAD). Different types of pump systems are available. To date, cardiac pumps have been used temporarily as a bridge-to-transplant in patients with heart failure. These patients have advanced disease, and pharmacological treatment has been insufficient. The need for organs in heart transplantation is greater than their availability. The development of new types of pumps that are substantially smaller may enable permanent treatment. These axial-flow left ventricular assist devices have recently been tested within the framework of scientific assessments. The target group for permanent treatment include patients with advanced heart failure who are either not suitable for transplantation or for whom organs are not available. An estimated 1 percent to 2 percent of all patients with severe heart failure and who are not candidates for transplantation, ie, 2000 to 4000 patients, comprise a potential target group for permanent treatment with this new type of cardiac pump.

Patient benefit

To date, somewhat over 3500 patients worldwide have received temporary mechanical support from implanted cardiac pumps (mainly displacement pumps). Several uncontrolled studies of patient series have reported that between 60 percent and 80 percent of patients survived until transplantation. Many of these patients could spend periods of time at home, and in some cases return to work. There is one randomized controlled trial comparing the long-term use of displacement pumps with pharmacological treatment for 129 patients with end stage heart failure who were ineligible for cardiac transplantation. The median survival was 408 days in the cardiac pump group compared to 150 days in the pharmacological group. Mechanical failures, all of which occurred after the initial 12 months, were responsible for 7 of 41 deaths in the cardiac pump group.

Scientific evidence

There is moderate* scientific documentation concerning the effects of using displacement pumps. The greatest interest is associated with the new axial-flow pumps which have recently been tested for both temporary and permanent treatment. Currently, there is no* scientific documentation on neither the patient benefits nor the costs associated with this type of cardiac pumps.

If the planned assessments show that the new axial-flow pumps have positive effects on patient survival and quality of life at a reasonable cost in relation to current methods, this new type of cardiac pumps may have a major impact on health care.

*This assessment by SBU Alert uses a 4-point scale to grade the quality and evidence of the scientific documentation. The grades indicate: (1) good, (2) moderate, (3) poor, or (4) no scientific evidence on the subject.

This summary is based on a report prepared at SBU in collaboration with Urban Lönn, MD PhD, Uppsala University Hospital and Henrik Casimir-Ahn, MD PhD, The University Hospital of Linköping. It has been reviewed by Assoc Prof Torkel Åberg, Norrland University Hospital, Umeå and Assoc Prof Ulf Dahlström, The University Hospital of Linköping.

The complete report is available only in Swedish.

Alert is a joint effort by the Swedish Council on Technology Assessment in Health Care (SBU), the Medical Products Agency, the National Board of Health and Welfare, and the Federation of Swedish County Councils.

References

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