Electrical superior vena cava isolation using photodynamic therapy in a canine model

Area of Science:

• Cardiovascular Interventions
• Medical Device Technology
• Photodynamic Therapy

Background:

• The shift towards multi-tip ablation catheters necessitates exploring innovative technologies for cardiac procedures.
• Electrical isolation of the superior vena cava (SVC) is crucial for treating certain arrhythmias.
• Existing point-to-point ablation strategies have limitations that newer technologies aim to overcome.

Purpose of the Study:

• To assess the feasibility of a ring-laser catheter for photodynamic therapy (PDT)-mediated electrical isolation of the SVC.
• To explore the advantages of a customizable catheter tip size in ablation procedures.
• To evaluate the safety and efficacy of this novel PDT laser-ring catheter technology.

Main Methods:

• Developed a prototype circular-laser-mapping catheter integrated with a Lasso™ mapping catheter.
• Administered talaporfin sodium as a photosensitizer followed by laser irradiation in canine models.
• Monitored for electrical isolation of the SVC, phrenic nerve injury, sinus node injury, and SVC stenosis acutely and chronically.

Main Results:

• Successfully achieved complete electrical SVC isolation in all seven canines using PDT-mediated ablation.
• No instances of sinus node injury, phrenic nerve palsy, or SVC stenosis were observed in acute or chronic evaluations.
• Isolation was achieved with a mean laser irradiation of 70.4 ± 71.4 J/cm and photosensitizer concentration of 30.9 ± 5.0 µg/mL.

Conclusions:

• The PDT laser-ring catheter provides a safe and effective method for immediate electrical SVC isolation.
• This technology offers a complication-free alternative for SVC isolation, potentially advancing cardiac ablation techniques.