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Contact catheters provide information over localised areas when used
in the conventional mapping of cardiac arrhythmias. Spatial and temporal changes of cardiac activation can be
identified by the introduction of multiple catheters or sequential point-by- point acquisition over multiple cardiac
cycles. However, there is a limit to the number of catheters that can be used and such sequential acquisition of
data is time consuming. These limitations may be particularly important when mapping arrhythmias that are
poorly tolerated by patients, such as haemodynamically unstable ventricular tachycardia (VT)1 or where the
arrhythmia is non-sustained which precludes sequential mapping techniques. What is required for mapping
complex arrhythmias is a rapid high- resolution mapping system, capable of providing global information of the
entire cardiac chamber simultaneously. The complex 3-dimensional geometry of the cardiac chamber, often in
the presence of structural heart disease with the geometric changes in chamber size during cardiac contraction
poses further problems for accurate endocardial contact mapping. The development of non-contact mapping,
using a catheter mounted multi-electrode array capable of reconstructing entire endocardial activation maps
when positioned inside the cardiac chamber, has overcome a number of limitations encountered by
conventional techniques. Results of the clinical utility of the non-contact system in treating patients with cardiac
arrhythmias have been published recently2,3.
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