Double-Dose Versus Standard-Dose Clopidogrel According to Smoking Status Among Patients With Acute Coronary Syndromes Undergoing Percutaneous Coronary Intervention

Background: Prior Studies have suggested better outcomes in smokers compared with nonsmokers receiving clopidogrel (“smoker's paradox”). The impact of a more intensive clopidogrel regimen on ischemic and bleeding risks in smokers with acute coronary syndromes requiring percutaneous coronary interventions remains unclear. Methods and Results: We analyzed 17 263 acute coronary syndrome patients undergoing percutaneous coronary intervention from the CURRENT‐OASIS 7 (Clopidogrel and Aspirin Optimal Dose Usage to Reduce Recurrent Events—Seventh Organization to Assess Strategies in Ischemic Symptoms) trial, which compared double‐dose (600 mg day 1;150 mg days 2–7; then 75 mg daily) versus standard‐dose (300 mg day 1; then 75 mg daily) clopidogrel in acute coronary syndrome patients. The primary outcome was cardiovascular death, myocardial infarction, or stroke at 30 days. Interactions between treatment allocation and smoking status (current smokers versus nonsmokers) were evaluated. Overall, 6394 patients (37.0%) were current smokers. For the comparison of double‐ versus standard‐dose clopidogrel, there were significant interactions in smokers and nonsmokers for the primary outcome (P=0.031) and major bleeding (P=0.002). Double‐ versus standard‐dose clopidogrel reduced the primary outcome among smokers by 34% (hazard ratio [HR] 0.66, 95% confidence interval [CI], 0.50–0.87, P=0.003), whereas in nonsmokers, there was no apparent benefit (HR 0.96, 95% CI, 0.80–1.14, P=0.61). For major bleeding, there was no difference between the groups in smokers (HR 0.77, 95% CI, 0.48–1.24, P=0.28), whereas in nonsmokers, the double‐dose clopidogrel regimen increased bleeding (HR 1.89, 95% CI, 1.37–2.60, P<0.0001). Double‐dose clopidogrel reduced the incidence of definite stent thrombosis in smokers (HR 0.41, 95% CI, 0.24–0.71) and nonsmokers (HR 0.63, 95% CI, 0.42–0.93; P for interaction=0.19). Conclusions: In smokers, a double‐dose clopidogrel regimen reduced major cardiovascular events and stent thrombosis after percutaneous coronary intervention, with no increase in major bleeding. This suggests that clopidogrel dosing in patients with acute coronary syndromes should be personalized, taking into consideration both ischemic and bleeding risk. Clinical Trial Registration URL: https://www.clinicaltrials.gov. Unique identifier: NCT00335452

Insight into capacity planning for cardiac catheterization services: Policy lessons learned from "Looking in the Mirror" over a decade

Background Cardiac catheterization (CATH) is key in the diagnosis and management of coronary artery disease. Increasing demand coupled with limited resources in a publicly funded system (e.g. Ontario, the largest province in Canada) resulted in a waitlist for this procedure. Our province has recommended maximum wait times (RMWT) for patients referred to CATH. The purpose of this study is to describe our experience over the past decade in attempting to meet RMWTs for patients needing CATH at our centre, and to discuss issues concerning capacity planning in providing timely service.Methods We measured the proportion of patients undergoing a procedure within the RWMT, and calculated both the mean number of patients and mean length of time on the wait list for each year over a decade for those referred to CATH using prospectively collected registry data. We identified factors that increased referrals or improved capacity. Wait time was compared to community standard RMWTs in order to establish if and how RMWTs were achieved.Results Despite a number of systematic and capacity improvements, RMWTs were not achieved until after the addition of a 4th laboratory.Interpretation Improving access to CATH in our centre was reactive to the increasing need of the community rather than based on anticipation of need and continuity of service within RMWTs. Registry data can help monitor key indicators (e.g. RMWT). Prudent use of this information should help policy makers with future expansion in our region.Cardiac catheterization Service delivery Wait times Capacity

Impact of clinical urgency, physician supply and procedural capacity on regional variations in wait times for coronary angiography

Abstract Background Despite universal health care, there continues to be regional access disparities to coronary angiography in Canada. Our objective was to evaluate the extent to which demand-side factors such as clinical urgency/need, and supply-side factors, as reflected by differences in physician and procedural supply account for these inequalities. Methods Our cohort consisted of 74,254 consecutive patients referred for coronary angiography in Ontario, Canada between April 1st 2005 and March 31st 2006, divided into three urgency strata based on a clinical urgency scale. Cox-proportional hazard models were developed, adjusting for age, gender, socioeconomic status (SES), region, and urgency score, with greater hazard ratios (HR) indicating shorter wait times. To evaluate mediators of any residual wait-time differences, we examined the influence of the regional supply of cath lab facilities, invasive cardiologists and general practitioners (GP). Results We found that the urgency score was a significant predictor of wait time in all three strata (urgent patients: HR 1.61 for each unit increase in patient urgency (95% Confidence interval (CI) 1.55-1.67); semi-urgent patients: HR 1.55 (95% CI 1.44-1.68); elective patients: HR 1.13 (95% CI 1.08-1.18)). After accounting for clinical need/urgency, regional wait time differences persisted; these were most consistently associated with variation in cath lab supply. The impact of invasive cardiologist supply was restricted to urgent patients while that of GP supply was confined to semi-urgent and elective patients. Conclusion We found that there remained significant regional disparities in access to coronary angiography after accounting for clinical need. These disparities are partially explained by variations in supply of both procedural capacity and physician services, most notably in elective and semi-urgent patients