Invasive Cardiology Practice Test 2026 - Free Invasive Cardiology Practice Questions and Study Guide

Active fixation involves a screw-in mechanism, a retractable helix at the lead tip that is rotated into the endocardial myocardium. This direct engagement with heart tissue provides secure, stable anchoring, allowing precise placement and reducing the chance of lead dislodgement after implantation. It also lets you reposition by unscrewing if the lead isn’t ideally seated. By contrast, tines offer passive fixation by catching on trabeculae, which is less controllable. Suturing the lead to the chest wall isn’t how transvenous leads are anchored, and saying there is no fixation mechanism is incorrect because the screw-in helix is the fixation method.