Congestive Heart Failure
How to Use a Beta Blocker
The addition of beta-blocker therapy to standard triple therapy for HF
(digoxin, diuretic and ACE inhibitor) such as in the U.S. Carvedilol
Trials1 (LVEF £ 35%; carvedilol
12.5-100mg/day) have shown a further 65% RRR in CV mortality (7.8% to
3.2 % ARR) in patients with NYHA class II-IV symptomatic HF. Carvedilol
has also been shown to produce a dose related increase in LVEF which averaged
8% and to lead to a 27% relative risk reduction in cardiovascular hospitalizations.
Similar benefits were obtained in other trials of beta-blockers in Heart
Failure (MERIT2 -metoprolol and CIBIS
II3 - bisoprolol). The Copernicus
trial has extended the benefit of b-blockade to Class IV HF patients4.
Despite this many physicians are reluctant to utilize beta-blockers in
heart failure for fear of provoking clinical deterioration. Physicians
should bear in mind that they already have many patients in their practice
with silent or asymptomatic LV dysfunction who are tolerating beta-blockers
very well (post MI patients). Judicious initiation of beta blockade will
not provoke sudden severe heart failure. Most patients tolerate the addition
of a beta-blocker very well. The key is to START LOW AND GO SLOW
utilizing the beta-blocker medications and doses used in the clinical
trials.
In addition the close monitoring required is a clinical deterrent to beta-blocker
usage. In many instances patients can be initiated on beta-blockers and
up-titrated with less frequent clinical visits. In this case a START
LOWER AND GO SLOWER strategy is advised and is particularly useful
in a busy primary care setting. Patients can up-titrate themselves and
backtrack if symptoms develop. It is recommended to start with the START
LOWER AND GO SLOWER beta-blocker protocol until you are familiar and
comfortable with beta-blocker therapy.
The accompanying beta-blocker titration protocols are recommended as
advice and do not replace clinical judgment or appropriate consultation.
Beta-blockers should be initiated in the stable HF patient, free of clinical
congestion. ACE inhibition should be optimized prior or simultaneous with
beta-blocker titration. Dietary, lifestyle and exercise interventions
should be carried out concurrently. All cardiac risk factors should be
modified aggressively. Treatable causes of HF should be identified. Reversible
triggers of HF should be dealt with.
See Beta-blocker titration protocols for both
the standard START LOW AND GO SLOW
and the START LOWER AND GO SLOWER protocols.
See the Guide for Heart Failure (HF) Management
for further guidance in this regard.
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