Angiographic predictors of adverse outcomes after percutaneous coronary intervention in patients with radiation associated coronary artery disease

OBJECTIVES: To determine procedural predictors of long-term outcomes for patients with radiation associated coronary artery disease (CAD) treated with percutaneous coronary intervention (PCI). BACKGROUND: Patients who develop CAD after external beam radiation therapy (XRT) for cancer are at high-risk for adverse events following PCI. It is unknown if specific angiographic features can predict outcomes in this population. METHODS: This is an observational study of 157 patients with malignancy who received XRT prior to PCI. Rates of major adverse cardiovascular and cerebrovascular events (MACCEs; all-cause mortality, myocardial infarction, repeat revascularization, or stroke) were compared across patient characteristics over time with the Cox proportional hazards and Kaplan-Meier's analyses. RESULTS: During follow-up of 5.4 ± 4.5 years, 91 (58%) patients had MACCE. On Kaplan-Meier's analysis of angiographic characteristics, MACCE was more frequent in patients with at least moderate target vessel calcification (P = 0.023), ostial stenosis (P = 0.049), target vessel diameter ≥ 3.0 mm (P = 0.018), a SYNTAX score ≥ the median of 11 (P = 0.014), or bare metal stenting (BMS)/balloon angioplasty (BA) compared to drug-eluting stenting (DES) (P = 0.006). Cardiac death was more frequent in patients with SYNTAX score ≥ 11 (P = 0.028) or BMS (P = 0.043). After multivariable adjustment for both angiographic and clinical characteristics, independent predictors of MACCE were BMS placement (P = 0.013), chronic kidney disease ≥ stage 3 (P = 0.019), New York Heart Association (NYHA) heart failure class ≥3 (P = 0.034), and SYNTAX score ≥ 11 (P = 0.041). CONCLUSIONS: In patients previously exposed to XRT treated with PCI, independent angiographic predictors of MACCE include SYNTAX score ≥ 11 and BMS placement, suggestive that DES should be preferred in this population.