Canadian Lead ExtrAction Risk Score Study (Retrospective Arm)

Nickname: CLEAR Score

Principal Investigators

Dr. Jamil Bashir, UBC Division of Cardiovascular Surgery, St. Paul’s Hospital

Dr. Marc Dubuc, Montreal Heart Institute

Dr. Jason Andrade, UBC Division of Cardiology

Participating centres

To be confirmed


The use of cardiac implantable electronic devices (CIEDs) continues to increase dramatically due to the combination of changing population demographics and multiple studies demonstrating improved quality of life and survival. However, coupled with the increased CIED implantation and intervention rate is the need for safe and effective methods for removing CIED systems, most commonly due to infection.

The Excimer laser sheath was introduced as a method of removal in 1992 and was first used in Canada at Vancouver General Hospital in 1996. Although laser lead extractions (LLE) have a high success rate with respect to lead removal, they carry a significant risk, with major complication rates ranging from 1% to 4%.

Despite widespread and growing utilization, current data on CIED extraction outcomes are largely limited to case series from high-volume centres with experienced operators, with virtually no population-based data. Further, no systematic analysis of the outcomes of LLE has been undertaken in Canada.

Primary Objectives

  1. To collect, report, analyse and benchmark the historical outcomes of laser lead extraction in order to establish the acute and long-term safety of transvenous LLE.
  2. To develop and validate a risk prediction score to aid in clinical decision making around LLE, and to help inform patients of the risks and benefits of LLE.

Secondary Objectives

  1. To describe demographic and clinical characteristics of patients who have undergone LLE.
  2. To describe the characteristics of leads that have undergone extraction.
  3. To evaluate the impact of lead advisories on historical extraction practices.
  4. To evaluate historical indications for LLE procedures as well as provincial variability in volume and indications for procedures.

Methodological Approach

This is a national, retrospective, multi-centre, observational study of consecutive patients that underwent LLE procedures across Canada (participating sites to be confirmed).  The study population will consist of all the patients who have undergone LLE between January 1, 1996 and December 31, 2013. A database containing information on clinical indications and demographics, extraction procedure, observed complications, and clinical success rates will be created.

Primary Outcome: Composite measure of efficacy and safety of LLE, including intra-procedural, post-procedural, short-term (30 days), and long-term (1 year) complications.

  • Major complication: Any outcome related to the procedure that causes persistent or significant disability, requires surgical reintervention, is life threatening or results in death within 30 days.
  • Minor complication: Any outcome related to the procedure that requires medical intervention but does not cause persistent or significant disability, nor threaten life or cause death.


The results of the study will provide valuable data regarding the success and complications rates for contemporary LLE procedures. This information will help refine the indications for LLE, inform the training and maintenance of competency standards, guide the development of new extraction tools and techniques, and potentially impact the way LLE is approached.