passive fixation
A lead attachment mechanism using soft tines or fins that lodge in cardiac trabeculations for anchoring.
Full Definition
Passive fixation utilizes soft, flexible tines or fins attached to the lead tip that become entangled in the natural trabeculations and structures within the heart chambers to provide lead stability. Unlike active fixation, this mechanism does not penetrate the myocardium but relies on the anatomical features of the cardiac chambers for anchoring. Passive fixation leads are typically easier to remove if extraction becomes necessary and may have lower acute thresholds initially. However, they may be less suitable in smooth-walled chambers or in patients with dilated cardiomyopathy where adequate trabeculations are absent.
Usage
Usage note: Hyphenate when used as a compound modifier: 'passive-fixation lead'.
In Context
- "Passive fixation provided adequate lead stability in the heavily trabeculated right ventricle." — Implant procedure report
- "The passive fixation mechanism showed stable positioning throughout the maturation period." — Follow-up device check