Symptom-to-Balloon Time is a Strong Predictor of Adverse Events Following Primary Percutaneous Coronary Intervention: Results From the Australian Capital Territory PCI Registry

Background Notwithstanding improvements in door-to-balloon time, adverse event rates after primary PCI have remained steady. We analysed the effect of symptom-to-balloon (STB) time, a reflection of total ischaemic time, on major adverse cardiovascular events (MACE) and explored predictors of prolonged STB time. Methods The study population included 1002 consecutive patients (22.4% women) with a mean age of 62.3 +/- 13.2 years, who underwent primary PCI during 2008-2014. Groups were compared for STB <= and > 240 min. Primary endpoint was one-year MACE, a composite of death, reinfarction, stent thrombosis or target vessel revascularisation. Results Symptom-to-balloon time was available in 893 patients of which 588 (65.8%) had STB <= 240 min and 305 (34.2%) had STB > 240 min. The incidence of one-year MACE increased significantly in a stepwise manner with increasing STB time (p for trend=0.003). Symptom-to-balloon time was an independent predictor of one-year MACE along with age > 70 years, final TIMI flow < 3, three vessel disease, cardiogenic shock and out-of-hospital cardiac arrest. We also performed a multivariate analysis to determine predictors of delayed treatment. Predictors of STB time > 240 min were age > 70 years, female gender, diabetes, absence of prehospital catheter laboratory activation and presentation to a non-PCI centre. Conclusion Incidence of MACE was strongly correlated with STB time and STB time was an independent predictor of MACE. We have identified specific subgroups with prolonged STB times (age > 70, female gender, absence of prehospital activation and presentation to a non-PCI centre). This information should inform future studies and strategies to minimise delays in these subgroups for improved outcomes.diabetes,