Mauri, Laura

Background: Randomized clinical trials are often criticized for not reflecting real-world practice. To understand the effect of site and patient selection on trial generalizability, we examined US patient and hospital participation within the Dual Antiplatelet Therapy (DAPT) Study, a broadly inclusive trial of PCI patients, using a linked analysis with the CathPCI Registry®. Methods: Within the CathPCI Registry, we identified patients undergoing PCI between September 1, 2009 and July 1, 2011 - the period of DAPT Study enrollment. We compared US patients enrolled in DAPT to CathPCI Registry patients meeting DAPT inclusion criteria. Characteristics of US DAPT sites were also compared to those of hospitals not participating in DAPT. Standardized differences (%) for all variables were estimated, with those greater than 10% considered significant. Results: Among 1,139,932 NCDR patients undergoing PCI, 748374 (65.7%) met the enrollment criteria for DAPT, and 23495 (2.1%) were enrolled. Enrolled patients were younger and had lower rates of prior stroke, CHF and peripheral vascular disease, but were similar with respect to race and gender compared with eligible patients (Table). Of the 1276 hospitals within the NCDR, 309 (24.2%) participated in DAPT. Hospital characteristics differed markedly, with DAPT-participating hospitals being larger (mean beds 468 vs. 311), more often located in urban settings (61.2% vs. 42.6%), more often affiliated with training programs (53.7% vs. 34.1%), and with higher annual PCI volumes (mean annual hospital volume 858 vs. 378 PCIs) compared with non-DAPT hospitals. Conclusions: While liberal inclusion criteria may allow randomized trials to better simulate “real-world” clinical practice, the process of site selection may encourage participation of higher volume, urban hospital settings. These findings are relevant to clinical trial interpretation and implementation of evidence-based practice throughout the healthcare system.

The optimal antithrombotic treatment regimen for patients with atrial fibrillation undergoing percutaneous coronary intervention with stent implantation represents a challenge in clinical practice. In 2016, an updated opinion of selected experts from the United States and Canada on the treatment of patients with atrial fibrillation undergoing percutaneous coronary intervention was reported. After the 2016 North American consensus statement on the management of antithrombotic therapy in patients with atrial fibrillation undergoing percutaneous coronary intervention, results of pivotal clinical trials assessing the type of oral anticoagulant agent and the duration of antiplatelet treatment have been published. On the basis of these results, this focused update on the antithrombotic management of patients with atrial fibrillation undergoing percutaneous coronary intervention recommends that a non–vitamin K antagonist oral anticoagulant be preferred over a vitamin K antagonist as the oral anticoagulant of choice. Moreover, a double-therapy regimen (oral anticoagulant plus single antiplatelet therapy with a P2Y 12 inhibitor) by the time of hospital discharge should be considered for most patients, whereas extending the use of aspirin beyond hospital discharge (ie, triple therapy) should be considered only for selected patients at high ischemic/thrombotic and low bleeding risks and for a limited period of time. The present document provides a focused updated on the rationale for the new expert consensus–derived recommendations on the antithrombotic management of patients with atrial fibrillation treated with oral anticoagulation undergoing percutaneous coronary intervention.

Background— Observed rates of restenosis after drug-eluting stenting are low (<10%). Identification of a reliable and powerful angiographic end point will be useful in future trials. Methods and Results— Late loss (postprocedural minimum lumen diameter minus 8-month minimum lumen diameter) was measured in the angiographic cohorts of the SIRIUS (n=703) and E-SIRIUS (n=308) trials. Two techniques, the standard normal approximation and an optimized power transformation, were used to predict binary angiographic restenosis rates and compare them with observed restenosis rates. The mean in-stent late loss observed in the SIRIUS trial was 0.17±0.45 mm (sirolimus) versus 1.00±0.70 mm (control). If a normal distribution was assumed, late loss accurately estimated in-stent binary angiographic restenosis for the control arm (predicted 35.4% versus observed 35.4%) but underestimated it in the sirolimus arm (predicted 0.6% versus observed 3.2%). Power transformation improved the reliability of the estimate in the sirolimus arm (predicted 3.2% [CI 1.0% to 6.7%]) with similar improvements in the E-SIRIUS trial (predicted 4.0% [CI 1.2% to 7.0%] versus observed 3.9%). In the sirolimus-eluting stent arm, in-stent late loss correlated better with target-lesion revascularization than in-segment late loss (c-statistic=0.915 versus 0.665). Conclusions— Because distributions of late loss with a low mean are right-skewed, the use of a transformation improves the accuracy of predicting low binary restenosis rates. Late loss is monotonically correlated with the probability of restenosis and yields a more efficient estimate of the restenosis process in the era of lower binary restenosis rates.