OBJECTIVES

This study sought to determine the frequency and impact of coronary calcification among patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndromes (ACS).

BACKGROUND

Small studies in patients with stable coronary artery disease have suggested a worse prognosis after PCI of calcified compared with noncalcified lesions. Little is known about the impact of coronary calcification on outcomes after PCI for patients presenting with non-ST-segment elevation and ST-segment elevation ACS.

METHODS

Data from 6,855 patients presenting with ACS in whom PCI was performed were pooled from 2 large-scale randomized, controlled trials, ACUITY (Acute Catheterization and Urgent Intervention Triage Strategy) and HORIZONS-AMI (Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction). One-year outcomes were analyzed according to the severity of PCI target lesion calcification (none/mild, moderate, or severe) as assessed by an independent angiographic core laboratory.

RESULTS

Target lesion calcification was severe in 402 patients (5.9%), moderate in 1,788 (26.1%), and none/mild in 4,665 (68.1%). Moderate/severe target lesion calcification was more frequent in older patients, men, hypertensive patients, and those presenting with ST-segment elevation myocardial infarction (STEMI). The unadjusted 1-year rates of death, cardiac death, definite stent thrombosis, and ischemic target lesion revascularization (TLR) and target vessel revascularization were significantly increased in patients with moderate/severe target lesion calcification. By multivariable analysis, the presence of moderate/severe target lesion calcification was an independent predictor of 1-year definite stent thrombosis (hazard ratio [HR]: 1.62; 95% confidence interval [CI]: 1.14 to 2.30; p = 0.007) and ischemic TLR (HR: 1.44; 95% CI: 1.17 to 1.78; p = 0.0007).

CONCLUSIONS

Moderate/severe lesion calcification was relatively frequent in patients with non-ST-segment elevation ACS and STEMI and was strongly predictive of stent thrombosis and ischemic TLR at 1 year. (Comparison of Angiomax Versus Heparin in Acute Coronary Syndromes [ACS]; NCT00093158; Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction; NCT00433966).