Relationship Between the Completeness of Revascularization and Myocardial Injury in Patients Treated With Percutaneous Coronary Intervention.

BACKGROUND

Clinical outcomes of patients suffering periprocedural myocardial injury and undergoing incomplete revascularization (IR) following percutaneous coronary intervention (PCI) has never been investigated.

OBJECTIVE

To investigate the relationship between different thresholds of post-PCI cardiac troponin (cTn) elevation and revascularization completeness in determining long-term clinical outcomes.

METHODS

Patients were stratified in tertiles according to preprocedural SYNTAX score (SS) (low: 0-6; medium: >6-11; high: >11) and residual SS (low: 0-4; medium: >4-8; high: >8). IR was defined by a rSS value >4. Three thresholds of myocardial injury were pre-specified: 5×, 35× and 70× 99th percentile upper reference limit (URL) increase of baseline cTn. Primary outcome was a composite of major adverse cardiac events (MACE) at two years of follow-up.

RESULTS

1061 patients undergoing PCI for stable coronary artery disease were enrolled. IR occurred in 249 (23.4 %) and major myocardial injury in 540 (50.9 %). Patients belonging to the highest tertile of SS showed an increased risk of experiencing IR and periprocedural myocardial injury. Two-year follow-up was available in 869. At multi-variate Cox's regression analysis, patients undergoing IR + cTn > 35 × URL and IR + cTn > 70 × URL showed an increased risk of MACE [HR 2.30 (1.19-4.41) and HR 3.20 (1.38-7.41); respectively].

CONCLUSIONS

Periprocedural myocardial injury is critically associated with MACE at two-year follow-up in patient treated with PCI who achieve IR. Despite conflicting evidence exists regarding the influence of periprocedural myocardial injury on clinical outcomes, patients undergoing IR seem to represent a high-risk subgroup.