[The impact of coronary artery calcification on the long-term outcomes after chronic total occlusion percutaneous coronary intervention].

Objective

Investigate the impact of calcification on the long-term outcomes of patients with coronary chronic total occlusion (CTO) after percutaneous coronary intervention (PCI).

Methods

A retrospective cohort study was conducted. Patients who underwent PCI and had at least one CTO lesion at Fuwai Hospital between January 2010 and December 2013 were consecutively enrolled. Calcification was evaluated by coronary angiography, and patients were divided into two groups: moderate/severe calcification group and non/mild calcification group. Clinical follow-up was completed up to 5 years. Incidence of PCI-related complications and immediate procedural outcomes were compared between two groups, and the primary endpoint was the target lesion failure (TLF) at 5 years after PCI. Clinical follow-up endpoint events were analyzed using Kaplan-Meier survival analysis with log-rank test, and Cox multivariate regression model was used to evaluate the relationship between calcification and TLF.

Results

The study included 2 659 CTO patients with an age of (57.2±10.5) years, of whom 442 (16.6%) were female, and among whom 13.5% (360/2 659) had moderate/severe calcification. Compared with the non/mild calcification group, the moderate/severe calcification group had a higher incidence of PCI-related complications (43.2% (156/361) vs. 32.5% (772/2 374), P<0.001) and procedural failure (34.3% (124/361) vs. 24.3% (577/2 374), P<0.001). Additionally, the moderate/severe calcification group showed a higher risk of the primary endpoint event (TLF) during the 5-year follow-up (19.8% vs. 15.3%, log-rank P=0.028). Higher incidence of cardiac death was observed in moderate/severe calcification group (5.7% vs. 2.7%, log-rank P=0.003). Cox multivariate regression analysis revealed that moderate/severe calcified plaques remained an independent risk factor for 5-year TLF after CTO-PCI (HR=1.34, 95%CI: 1.01-1.79, P=0.043).

Conclusion

Compared with CTO patients with non/mild calcification, those with moderate/severe calcification have higher procedural failure and complication rates, as well as poorer long-term prognosis, mainly due to an increase in cardiac death.