WCD Compliance and Limitations — EECC MCQ

Correct answer: B — WCD requires near-continuous wear (>22 hours/day for maximum protection) — compliance is the major limitation; the device cannot provide anti-tachycardia pacing (ATP) or bradycardia pacing, and the patient must remain conscious to either confirm or abort therapy (response buttons)

WCD (LifeVest) limitations per ESC 2022 VA/SCD Guidelines: (1) COMPLIANCE: must be worn ≥22 hours/day (during showering/bathing it is removed — vulnerable period); the VEST trial showed average daily wear was only ~18 hours, reducing effectiveness; (2) NO ATP capability: WCD can only deliver shocks, not anti-tachycardia pacing (which terminates 80% of monomorphic VT painlessly in ICD patients); (3) NO bradycardia pacing: no backup pacing for bradycardia/asystole; (4) CONSCIOUS patient interaction: when VT/VF is detected, the device alerts the patient (vibration + alarm); the patient must press response buttons to ABORT therapy if they are conscious (to prevent inappropriate shocks) or allow therapy if they are unresponsive — this system can fail if the patient is incapacitated but able to involuntarily press buttons; (5) SKIN contact: requires good electrode-skin contact; poor contact increases artefact detection and inappropriate alerts; (6) FALSE ALARMS: ~1-2/day requiring patient response (can be distressing).

Reference: ESC (2022): VA/SCD Guidelines; VEST Trial