Near-Infrared Spectroscopic Mapping of the Human Epicardium

Area of Science:

• Cardiovascular Interventions
• Biomedical Optics
• Medical Imaging

Background:

• Epicardial catheter ablation is crucial for ventricular tachycardia (VT) but faces challenges from epicardial adipose tissue and coronary vessels.
• These anatomical structures can impede ablation delivery and complicate procedures, potentially reducing efficacy and safety.

Purpose of the Study:

• To evaluate the feasibility of catheter-based near-infrared spectroscopy (NIRS) for identifying epicardial adipose tissue and coronary blood vessels.
• To develop and validate optical indices derived from NIRS for improved detection of these ablation obstacles.

Main Methods:

• Ex vivo mapping of 18 human ventricles using NIRS catheters with varying optical source-detector separations (0.6 and 0.9 mm).
• Development of a logistic regression model for adipose detection and novel optical indices for both adipose and blood vessel detection.
• Performance evaluation using area under the receiver operating characteristic curve (AUROC) for binary classification tasks.

Main Results:

• The logistic regression model achieved high AUROCs for adipose detection (0.907 at 0.6 mm SDS, 0.911 at 0.9 mm SDS).
• Novel optical indices demonstrated strong performance for adipose detection (AUROCs of 0.881 and 0.873) and blood vessel detection (AUROC of 0.859 at 0.9 mm SDS).

Conclusions:

• Catheter-based NIRS is a promising technology for real-time identification of epicardial adipose tissue and coronary vessels.
• This capability can significantly enhance the efficacy and safety of catheter ablation procedures for ventricular tachycardia.