Patient Alert to detect ICD lead failure: efficacy, limitations, and implications for future algorithms

Area of Science:

• Cardiology
• Biomedical Engineering
• Medical Device Technology

Background:

• Implantable cardioverter-defibrillators (ICDs) are crucial for managing cardiac arrhythmias.
• Lead dysfunction is a significant complication affecting ICD performance and patient safety.
• Early detection of lead failures is essential for timely intervention and improved patient outcomes.

Purpose of the Study:

• To evaluate the effectiveness of the Patient Alert algorithm in detecting implantable cardioverter-defibrillator (ICD) lead failures.
• To assess the utility of Patient Alert for identifying lead dysfunction in a prospective cohort.
• To compare the performance of Patient Alert with continuous lead integrity monitoring (SIC).

Main Methods:

• A prospective study involving 360 ICD patients followed for 22 months.
• Patient Alert algorithm monitored lead impedance for abnormal values.
• Sensing Integrity Counter (SIC) was used for retrospective analysis of lead integrity.
• Performance metrics including sensitivity and positive predictive value (PPV) were calculated.

Main Results:

• Patient Alert detected 3 of 10 ICD lead failures.
• The Sensing Integrity Counter (SIC) identified an additional 4 lead defects retrospectively.
• Combined use of Patient Alert and SIC detected 100% of ICD lead failures.
• The combination also identified 71.4% of severe lead complications.

Conclusions:

• Patient Alert alone detects approximately one-third of ICD lead failures.
• Integrating SIC with Patient Alert significantly enhances sensitivity for lead failure detection.
• False positives with SIC may occur with integrated bipolar leads.
• Further improvements in Patient Alert could incorporate SIC and automated threshold measurements for better complication detection.