Early mortality in prophylactic implantable cardioverter-defibrillator recipients: development and validation of a clinical risk score

Area of Science:

• Cardiology
• Medical Devices
• Predictive Analytics

Background:

• Implantable cardioverter-defibrillators (ICDs) are crucial for reducing sudden cardiac death in patients with cardiomyopathy.
• Current guidelines limit ICD use in patients with a life expectancy under 1 year due to low benefit.
• Early mortality after ICD implantation remains a concern in primary prevention populations.

Purpose of the Study:

• To identify predictors of early mortality (within 1 year) after ICD implantation.
• To develop and validate a risk score for early mortality in primary prevention patients.
• To aid in risk assessment for selecting appropriate ICD candidates.

Main Methods:

• A prediction cohort of 861 primary prevention ICD recipients was analyzed.
• A risk score was developed using multivariate analysis, incorporating age, left ventricular ejection fraction (LVEF), atrial fibrillation, and estimated glomerular filtration rate (eGFR).
• The risk score was validated in a separate cohort of 706 patients.

Main Results:

• A risk score based on age (≥75), LVEF (≤20%), atrial fibrillation, and eGFR (≤30) identified low, intermediate, and high-risk groups.
• 1-year mortality rates were 3.4% (low risk), 10.9% (intermediate risk), and 38.9% (high risk) in the prediction cohort.
• Validated 1-year mortality rates were 2.5% (low risk), 13.2% (intermediate risk), and 46.3% (high risk), confirming the score's predictive power.

Conclusions:

• A simple risk score effectively stratifies patients for early mortality risk post-ICD implantation.
• The identified predictors (age, LVEF, eGFR, atrial fibrillation) are key factors in early mortality.
• This risk score can assist clinicians in evaluating ICD candidacy and optimizing patient selection.