The answer is yes. Although a pacemaker can reduce the risk of dying
from heart failure, a person with heart failure can still die even if
she or he has a pacemaker that is working properly.
Pacemakers are usually used to treat problems with electrical
conduction in the heart, called arrhythmias. A normal heart creates
its own electrical impulse that spreads through the heart muscle and
leads to muscle contraction and beating of the heart, which provides
blood flow to the brain and all other tissues of the body. An
artificial pacemaker provides an external impulse (or "discharge")
that can stimulate the heart, thus restoring or maintaining a regular
heartbeat for patients with abnormalities in cardiac impulse formation
and/or transmission. For patients with heart failure, a pacemaker that
provides a discharge in the large chambers (a bi-ventricular pacer)
can correct the timing of the electrical signals in the heart,
allowing the heart to contract in a coordinated fashion and thus
improve the contraction of the heart and the amount of blood that is
pumped to the body.
However, a pacemaker, even if functioning correctly, cannot always
prevent worsening heart failure and death. The pacemaker will continue
to deliver electical impulses to the heart, but if the heart muscle is
not responding, or the impulses are not being transmittted normally in
the heart, the heart may stop beating altogether or may be unable to
beat strongly enough to provide enough blood flow to the brain, and
death can result. Other problems with heart failure that can lead to
death include a build-up of fluid in the lungs called pulmonary edema,
which can prevent oxygen from getting into the blood from the lungs.
The bottom line is that a pacemaker can help a sick heart to beat more
effectively, but it cannot replace a sick heart.
I hope this helps to understand the issue. Please let me know if you
have any further questions or need any clarification. My reading was
done on www.uptodate.com, which requires a membership subscription,
but other good resources are free online.
For example:
Pacemaker Therapy Halves Heart Failure Deaths
http://www.hopkinshospital.org/health_info/Heart/Reading/pacemaker_therapy.html
A very good review article on the topic of mortality and pacemakers,
which would be available at any science library:
Cardiac resynchronization and death from progressive heart failure: a
meta-analysis of randomized controlled trials. Bradley DJ; Bradley EA;
Baughman KL; Berger RD; Calkins H; Goodman SN; Kass DA; Powe NR. JAMA
2003 Feb 12;289(6):730-40. CONCLUSIONS: Cardiac resynchronization
reduces mortality from progressive heart failure in patients with
symptomatic left ventricular dysfunction. This finding suggests that
cardiac resynchronization may have a substantial impact on the most
common mechanism of death among patients with advanced heart failure.
Cardiac resynchronization also reduces heart failure hospitalization
and shows a trend toward reducing all-cause mortality.
Best regards,
RMH
Search strategy:
Uptodate.com "cardiac pacemakers"
Google.com pacemaker heart failure death
://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GGLD,GGLD:2004-03,GGLD:en&q=pacemaker+heart+failure+death |
