Maurizio Gasparini, Fabrizio
Pizzetti*, Massimo Mantica, Maurizio Lunati°, Augusto Foresti.
Operative Unit of Cardiology, Clinical Institute Humanitas, Rozzano (MI), * Division of
Cardiology,
S. Spirito Hospital, Casale Monferrato (AL), ° Department of Cardiology "A. De
Gasperis", Niguarda Hospital, Milan, Italy
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Atrial fibrillation (AF) is the most common and
important clinical arrhythmia. In the Framingham Study1
the population examined had a 2% chance of developing chronic AF during the 22 years of
observation; in the elderly (59-79 years) incidence of AF was 539 new cases per year per
100.000 inhabitants2. AF usually followed the
development of overt cardiovascular disease and, most importantly, was associated with a
doubling of total mortality and cardiovascular mortality. AF is often a precipitating
cause of worsening of health conditions and of sense of well being. In addition, it can
determine heart failure, thromboembolism and syncope. Consequently AF has a high economic
cost, in terms of hospitalization, need for drugs or medical examinations and loss of
working capacity.
The traditional therapy for AF has been using antiarrhythmic drugs to control heart
rate or to restore and maintain sinus rhythm, but their efficacy, tolerability and safety
are very far from being satisfactory; thus new therapeutical approaches have been
investigated in order to better control, or treat, this arrhythmia. The first attempts to
control atrial fibrillation without the use of drugs were made with surgical techniques,
such as the corridor technique proposed by Guiraudon3,
but the most effective, the Maze intervention, was described by Cox and his group4 a few years later. The obvious limitations due to
invasivity and the possible complications, caused the research to direct itself towards
the goal of reducing, or interrupting, atrio-ventricular (AV) nodal conduction, with a non
surgical approach, in order to regularize the heart rate. For the last 15 years a
transcatheter interventional technique has been used which has produced increasingly
positive results, starting with AV nodal ablation with direct current (DC) shock, then
with RF delivery (both followed by pacemaker implantation), up to the newest techniques of
radio frequency (RF) AV node modulation. The most recent attempts suggest the opportunity
of eliminating the arrhythmic circuit of AF, without damaging the AV node, mimicking the
surgical Maze procedure.
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