Cardiovascular Journal of Africa: Vol 30 No 3 (May/June 2019)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 30, No 3, May/June 2019 178 AFRICA
25% of AM-treated patients are forced to discontinue treatment
due to its side effects.
As an alternative, short-burst therapy with oral AM appears
to significantly improve six-week and six-month sinus rhythm
maintenance rates following cardioversion, without exposing
patients to the adverse effects of long-term AM therapy.60
In patients regaining sinus rhythm after the first episode of
persistent AF, three months of AM therapy after reversion is a
reasonable option for rhythm control, with significantly lower
recurrences after 18 months.61
The superior efficacy of this drug is partially overshadowed
by the adverse effects that occur in 15 to 50% of cases, from
the first year of treatment to prolonged treatment. Cardiac,
pulmonary, thyroid and hepatic side effects are well known. For
safe use, the following are recommended: semi-annual thyroid
function and transaminase tests, an annual chest X-ray, as well
as an annual ECG in all AM patients.62
Conclusions
Once installed, AF can induce irreversible electrophysiological,
histopathological or immunological changes. With the
pharmacological advances of the last decades, despite its
adverse reactions, AM is one of the most commonly used anti-
arrhythmic agents. It remains the most effective medication for
the maintenance of sinus rhythm in patients with AF and the
most used drug for pharmacological cardioversion. This is due
to its multivalent profile, with a complex electrophysiological
activity combined with an anti-inflammatory and vasodilatory
effect.
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