Confirming pericardial access by using impedance measurements from a micropuncture needle

Area of Science:

• Medical Devices
• Biomedical Engineering
• Interventional Cardiology

Background:

• Pericardial access is challenging due to difficulties in confirming needle placement and avoiding organ injury.
• Conventional imaging lacks the soft-tissue guidance needed for safe pericardial access.
• A system is required to confirm needle tip location and prevent inadvertent organ damage.

Purpose of the Study:

• To develop and evaluate a novel bioimpedance monitoring system for enhanced pericardial access.
• To assess the system's ability to differentiate between various tissues during needle insertion.
• To improve the safety and efficiency of pericardial access procedures.

Main Methods:

• A 21G micropuncture needle was modified with two electrodes at its tip for continuous bioimpedance monitoring.
• The modified needle was used for pericardial access in porcine models.
• Electroanatomical mapping was employed for in vivo visualization, and bioimpedance data were analyzed retrospectively.

Main Results:

• Significant differences in bioimpedance (P < .01) were observed across various tissues, including subcutaneous space, mediastinum, pericardial space, myocardium, and blood.
• Phase data in the frequency domain correlated well with the needle's position within the pericardial space.
• Threshold analysis effectively distinguished lung and blood tissues from others, with specific thresholds identified.

Conclusions:

• Continuous bioimpedance monitoring from a modified needle can reliably differentiate tissues during pericardial access.
• This system, when combined with traditional imaging, confirms pericardial space entry and prevents inadvertent organ puncture.
• The developed system offers a safer and more efficient approach to needle-access procedures in the pericardium.