subsequent dose increase to ensure that there is no deterioration
in symptoms, significant bradycardia, or hypotension. In patients
with suspected or known renal impairment, it is recommended
that serum biochemistry is also monitored. A suggested protocol
is as follows: initiate carvedilol at 3.125mg twice daily; the dose
may be doubled at intervals of two weeks to a maximum of 25mg
twice daily, depending upon tolerance.
It is clear that beta blockers are of prognostic benefit in patients
with stable CHF who are in NYHA class II to III. However, there
are several important areas in which the effect of beta blocker
therapy is unknown. For example, should we be using beta
blockers to treat asymptomatic patients with evidence of systolic
ventricular dysfunction and is there a role for beta blocker
therapy in the patient post-myocardial infarction who has
ventricular impairment? Clinical trials are currently being
performed to answer these questions.
Evidence of a beneficial effect of beta blockers on the syndrome
of heart failure is accumulating. The use of beta blockers in this
context may prove to be one of the most important pharmaco-
logical “re-discoveries” in cardiology in recent years.
RReeffeerreenncceess
1 Swedberg K. History of beta-blockers in congestive heart failure. Heart
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2 The Cardiac Insufficiency Bisoprolol Study II (CIBIS-II): a randomised
trial. Lancet1999; 335533 : 9–13.
3 Effect of metoprolol CR/XL in chronic heart failure: Metoprolol CR/XL
Randomised Intervention Trial in Congestive Heart Failure (MERIT-
HF). Lancet1999; 335533 : 2001–7.
4 Packer M, Colucci WS, Sackner-Bernstein JD et al. Double-blind,
placebo-controlled study of the effects of carvedilol in patients with
moderate to severe heart failure. The PRECISE Trial. Prospective
Randomized Evaluation of Carvedilol on Symptoms and Exercise.
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