Introduction
Catheter ablation is a safe and effective treatment strategy of cardiac
arrhythmias and is increasingly performed world-wide. Beside the fact
that cardiac arrhythmias are very versatile atrial fibrillation (AF) is
the most common form which affects increasing numbers of patients.
Pulmonary vein isolation (PVI) by catheter ablation has shown high
success rates for treatment of paroxysmal (PAF) and persistent AF
(PersAF). Novel single-shot ablation devices implementing diverse energy
sources (cryothermal, laser, pulse field ablation (PFA), radiofrequency
(RF)) have shown excellent acute and long-term success rates with
decreased procedure time compared to RF based 3D mapping and
point-by-point PVI. Due to the fact that single-short devices are mainly
designed for PVI they have several limitations concerning versatility,
flexibility and adaptability to different anatomies.
Recently 3D mapping and point-by-point based catheter ablation achieved
several improvements by implementing contact force (CF), ablation index
(AI) or lesion size index (LSI)
guided RF ablation which have been shown to decrease procedure time,
improving safety and patients outcome. Latest achievements are
high-power short-duration (HP-SD) ablation with a maximum of 50W and
very HPSD (vHPSD) ablation with maximum of 70-90W which have been
introduced to clinical practice. In CF guided ablation procedures power
is limited to 50W, while in a power-controlled ablation mode without CF
sensing catheter power is limited to 70W. Although these concepts seem
to be safe and effective, no real time temperature monitoring is
possible because conventional catheters were utilized in those studies.
However, it has been shown that real-time subendocardial tissue
temperature monitoring during RF energy delivery is a direct indicator
of lesion formation but measurements by temperature sensors embedded in
the catheter tip have been shown to be not an accurate indicator of
actual tissue temperature.