Cardiovascular and bleeding risks of inactive cancer in patients with acute myocardial infarction who received primary percutaneous coronary intervention using drug-eluting stent and dual/triple antithrombotic therapy.

Background: Active cancer associates with increased cardiovascular and bleeding risks in patients with acute myocardial infarction (AMI). Recent chemotherapeutic agents have improved survival rate which enables to induce inactive status of cancer. However, whether cardiovascular and bleeding risks still exist in AMI patients with inactive cancer remains unknown.

Methods: The current study is a retrospective cross-sectional study including 712 AMI patients receiving primary percutaneous coronary intervention (PCI) with drug-eluting stent between 2007 and 2017. Primary PCI in ST-segment elevation myocardial infarction and non-ST-segment elevation myocardial infarction subjects was defined as PCI performed within 48 and 72 hours of symptom onset, respectively. Cardiovascular (= all-cause death + non-fatal MI + stroke) and bleeding events were compared in AMI patients with and without inactive cancer.

Results: Inactive cancer was identified in 11.1% of study subjects. Patients with inactive cancer were older (P<0.001) with atrial fibrillation (P<0.001), chronic kidney disease (P<0.001), anemia (P<0.001) and a higher prevalence of Killip class IV (P<0.001). Dual (82.3% 86.7%) and triple (17.7% 13.3%, P=0.34) antithrombotic therapies were commenced. Nearly 80% of subjects switched to single antithrombotic therapy around 1.5 years after dual/triple antithrombotic therapies (77.2% 77.3%, P=0.994). During the 2.9-year observational period, inactive cancer was associated with 3.59-fold elevated risk for experiencing a composite of cardiovascular and bleeding events (95% CI: 2.13-6.04, P<0.001). Furthermore, after adjusting clinical characteristics, inactive cancer was an independent predictor for bleeding events (HR: 3.98, 95% CI: 1.90-8.34, P<0.001). Of particular interests, even after switching to single antithrombotic therapy, an elevated bleeding risk was still observed in inactive cancer subjects (P<0.001).

Conclusions: Inactive cancer worsened clinical outcome, especially bleeding risks in AMI subjects, underscoring to further optimize their antithrombotic managements.