How does a passive fixation lead secure itself?

A passive fixation lead secures itself primarily by the tines being lodged into the trabeculae, which are small, beam-like structures found in the heart muscle, particularly within the right ventricle. These tines, or prongs, are designed to expand once they are in place, gripping the inner wall of the heart and preventing movement. This mechanical retention allows the lead to remain stable, ensuring consistent pacing and proper function.

This method of fixation is advantageous because it doesn't require additional energy sources or complicated mechanisms, making the lead easier to implant and reliable over time. The structural integrity provided by the engagement with the trabecular network minimizes the risk of dislodgement from usual physiological activity, ensuring continued effective pacing support. The design effectively exploits the natural anatomy of the heart to maintain lead position, demonstrating a blend of engineering and biological compatibility.