michael s
(Michael S)
#1
56 Which patients with heart failure should have a
beta blocker? How do I start it and how should I
monitor therapy?
Rakesh Sharma
More than 25 years ago it was proposed that beta blockers may be
of benefit in heart failure^1 and yet, until recently, there has been a
general reluctance amongst the medical profession to prescribe
them for this indication. This is not entirely surprising, as not too
long ago heart failure was widely considered to be a major
contraindication for the use of beta blockers. There is now consid-
erable evidence from major clinical trials that beta blockers are
capable of improving both the symptoms and prognosis of
patients with congestive heart failure (CHF).
The results from the second Cardiac Insufficiency Bisoprolol
Study (CIBIS-II) and the Metoprolol CR/XL Randomised
Intervention Trial in Heart Failure (MERIT-HF) have shown that
selective 1 antagonists (i.e. bisoprolol and metoprolol
respectively) can improve survival in patients with CHF.2,3
Carvedilol, a relatively new agent, is a non-selective beta blocker,
which also has antioxidant effects and causes vasodilatation. A
multi-centre US study showed there to be a 65% mortality
reduction with carvedilol as compared with placebo.^4 At present
it is not clear whether 1 selectivity is important with respect to
therapy in CHF, and this question is currently being addressed in
the Carvedilol and Metoprolol European Trial (COMET).
In the UK, carvedilol has been licensed for the treatment of
mild to moderate CHF (NYHA class II or III) and bisoprolol is
also likely to be approved in the near future. Prior to
commencement with beta blockers, patients should be clinically
stable and maintained on standard therapy with diuretics, ACE
inhibitors +/– digoxin. There is insufficient evidence at present to
recommend the treatment of unstable or NYHA class IV patients.
The Carvedilol Prospective Randomised Cumulative Survival
Trial (COPERNICUS), which is recruiting patients with severe
CHF, (NYHA class IIIB-IV) will hopefully be able to answer this
question in the future.
Treatment should be initiated at a low dose and be increased
gradually under supervised care. The patient should be
monitored for 2–3 hours after the initial dose and after each
