Regional differences in survival after ICD implantation.

Area of Science:

• Cardiology
• Public Health
• Health Services Research

Background:

• The implantable cardioverter-defibrillator (ICD) is crucial for preventing sudden cardiac death.
• Significant unexplained variations in 3-year mortality post-ICD implantation exist in Belgium.
• Center volume and socio-economic factors are potential contributors to these survival differences.

Purpose of the Study:

• To investigate the unexplained variations in 3-year mortality following first-time ICD implantation in Belgium.
• To determine the impact of center volume and socio-economic factors on patient survival after ICD implantation.

Main Methods:

• Retrospective analysis of 9647 patients undergoing first ICD implantation in Belgium (2010-2016).
• Comparison of demographics, 30-day, and 3-year mortality between low- and high-volume centers.
• Statistical analysis including Chi-squared, Mann-Whitney U, Kaplan-Meier, and multivariable Cox models.

Main Results:

• Low-volume centers treated patients with more comorbidities and higher rates of ischemic heart disease and primary prevention.
• Kaplan-Meier analysis revealed significantly higher 3-year mortality in low-volume centers (16.3% vs. 11.4%).
• Center volume remained an independent predictor of 3-year mortality (HR 1.300), but similar 30-day mortality suggests other factors are involved. Socio-economic factors were also associated with survival differences.

Conclusions:

• Substantial survival disparities exist post-ICD implantation across Belgian centers, extending beyond a simple volume-outcome relationship.
• Center characteristics and patient populations vary significantly and are influenced by socio-economic variables.
• Further research is warranted to explore the association between socio-economic factors and long-term survival after ICD implantation.