Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Ablation Techniques D-PO02 - Poster Session II (ID 47) Poster

D-PO02-169 - Optical Spectroscopy-integrated Catheters For On-line Monitoring Of Rf Ablation Efficacy (ID 1041)

Disclosure
 R.P. Singh-Moon: Nothing relevant to disclose.

Abstract

Background: Suboptimal lesions have been reported as a major causal factor in arrhythmia recurrence following RFA therapy despite validating their acute electrical effects. Tissue structural and biomolecular changes undergone during thermal treatment have been shown detectable by optical spectroscopy and could potentially serve as complementary guidance for intra-procedural evaluation of lesion adequacy.
Objective: We evaluated the use of optical spectroscopic tissue interrogation available at the catheter tip to assess catheter contact and directly monitor RFA delivery.
Methods: Various optically-integrated RF catheters were designed and tested ex vivo in both swine (n=40) and human donor (n=16) cardiac wedges. Additionally, a set of non-survival pilot experiments were conducted to test in vivo deployment and RFA monitoring in pigs (n=7). Both Optical measurements were sampled simultaneously alongside standard RF parameters for comparison. The extent of lesion formation was evaluated either using TTC staining (swine) or trichrome histology (human). Lesion optical indices (LOIs), designed to capture spectral changed induced by treatment, were derived from optical measurements and compared to treatment.
Results: LOIs values were well correlated (up to r = 0.895, n=39) with irrigated lesion size as determined by TTC. In vivo optical contact was clearly discernible by an increase in spectral reflectance signal and was in agreement with bipolar electrogram recordings. In overtreated lesions (n = 5) created ex vivo, there was an increase by an average of 17.3% before fall of 10.87% in LOI values prior to steam pop cavitation. Similar spectral features were observed in both irrigated and non-irrigated lesions.
Conclusion: Optical spectroscopic signatures detectable by fiber-optic integrated catheters are demonstrated to provide meaningful information regarding tissue-contact and prediction of lesion size and steam pop. Such insight could be integrated with conventional parameters to enhance tissue characterization for safe and effective lesion delivery.
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