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 >240min. 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 ≤240min and 305 (34.2%) had STB >240min. 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 >240min 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, diabetes, 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.

Efficacy of non-compliant balloon post-dilation in optimization of contemporary stents: A digital stent enhancement study.

BACKGROUND: There is no evidence from randomized trials for the benefit of routine non-compliant balloon (NCB) post-dilation after stent deployment. Despite being the gold standard, intravascular ultrasound is infrequently performed due to time and cost constraints and a suitable alternative technology is required for routine assessment of stent expansion. The purpose of this study was to assess the contribution of NCB post-dilation in optimizing contemporary stents by using digital stent enhancement (DSE). METHODS: We treated 120 patients with stent insertion and assessed the stents with DSE before and after NCB use. Optimal expansion was defined as the minimum stent diameter (MSD) ≥ 90% of the nominal stent diameter, an adaptation of the MUSIC and POSTIT trial criteria. Stent deployment was performed at 12 atm pressure followed by routine NCB post-dilation at ≥ 14 atm. RESULTS: The mean reference diameter on QCA was 2.75 mm (SD 0.63) and mean stent diameter was 3.15 mm (SD 0.46). At a mean stent deployment pressure of 11.7 atm (SD 2.4), only 21% of stents were optimally expanded. After NCB inflation at a mean of 16.9 atm (SD 2.8), MSD increased by 0.26 mm (SD 0.24), optimal stent expansion increased from 21% to 58% and mean stent symmetry ratio increased from 0.83 to 0.87 (p < 0.0001). CONCLUSIONS: Contemporary stents are sub-optimally expanded in the majority of cases after standard deployment compared with nominal sizes. Adjunctive NCB post-dilation optimized an additional 37% of stents. DSE analysis can assist in qualitative and quantitative stent assessments and can potentially facilitate a selective NCB post-dilation strategy to achieve optimal stent expansion.

Prehydration alone is sufficient to prevent contrast-induced nephropathy after day-only angiography procedures--a randomised controlled trial.

BACKGROUND: Contrast agents used in angiography procedures for patients with cardiovascular disease are known to cause contrast-induced nephropathy (CIN), which may be partially due to the production of nephrotoxic oxygen-free radicals. It is uncertain whether administration of intravenous (IV) anti-oxidant, N-acetylcysteine (NAC), can prevent reduction in renal function and whether this is a cost-effective approach. METHODS: Sixty-five day-only patients with renal impairment (mean serum creatinine concentration 0.16+/-0.03 mmol/l) due to undergo coronary or peripheral angiography and/or stenting were randomly assigned to IV NAC 300 or 600 mg immediately before and after the procedure or IV fluid alone. RESULTS: Of the 60 patients with complete data, none had acute CIN (increase in serum creatinine concentration > or = 0.044 mmol/l, 48 h after administration of contrast agent). Eight patients (13%) have demonstrated an increase in their serum creatinine concentration > or = 0.044 mmol/l 30 days after administration of contrast agent: 2/19 (11%) in the control group, 2/21 (10%) in the 600 mg NAC group and 4/20 (20%) the 300 mg NAC group (p = 0.66). The mean volumes of contrast agent used and prehydration given for each of the three groups did not differ significantly (p > 0.83). There was significant improvement in creatinine clearance within each group from baseline to 30 days (p < or = 0.03), but no significant difference between the groups at 48 h and 30 days (p > or = 0.43). Considering the cost of NAC and its administration, we estimate that this would translate to a saving of dollar 26,637 per annum. CONCLUSION: For day-stay patients with mild-to-moderate chronic renal impairment undergoing angiography and/or intervention, prehydration alone is less complicated and more cost-effective than a combination of IV NAC (at doses used) and hydration.