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Introduction: Carotid bifurcation stenosis may co-exist simultaneously with more proximal common carotid artery (CCA) atherosclerotic plaquing, primarily at the vessel origin in the aortic arch. This scenario is relatively infrequent and its' management does not have quality randomized data to support medical vs surgical treatment. It is logical to treat any high grade common carotid lesions proximal to a carotid bifurcation endarterectomy (CEA) site both to prevent perioperative emboli or thrombosis as well as future embolization. Prior long-term investigations of the combined treatment paradigm have been low volume analysis. Further, prior studies focus on perioperative outcomes with respect to stroke prevention. The only prior VQI study investigating mid-term outcomes following simultaneous CEA with proximal CCA endovascular therapy provided data on less than 10 patients beyond 1.5 years. The long-term follow-up (LFTU) component initiative within VQI has been emphasized in recent years, now allowing for much more robust LTFU analysis. Methods: Four cohorts were created for perioperative outcome analysis and Kaplan Meier freedom from event analysis: CEA in isolation for asymptomatic disease; CEA in isolation for symptomatic patients; CEA with proximal CCA endovascular intervention for asymptomatic; and, CEA with proximal CCA intervention for symptomatic patients. Binary logistic multivariable regression was performed for perioperative neurological event and 90-day mortality risk determination and Cox multivariable regression analysis was performed for long term freedom from cumulative ischemic neurological event and long-term mortality analysis. Symptomatology and type of surgery (CEA with or without CCA intervention) were individual variables in the multivariable analysis. Neurological ischemic event in this study encompassed transient ischemic attack (TIA) and stroke combined. Results: We noted a statistically significant (P <.001) escalation in rates of perioperative neurological event, myocardial infarction (MI), carotid re-exploration, 90 day mortality and combined neurological event and 90 day mortality moving from: A) asymptomatic CEA in isolation to B) symptomatic CEA in isolation to C) asymptomatic CEA combined with proximal CCA intervention to D) symptomatic CEA in combination with proximal CCA intervention. The positivity rate for the combined outcome of perioperative ischemic neurological event and 90 day mortality was 2.2% amongst asymptomatic CEA in isolation, 4.1% amongst symptomatic CEA in isolation, 4.4% amongst asymptomatic CEA in combination with proximal CCA intervention; and 8.8% in patients with symptomatic lesions undergoing combined CEA with proximal CCA intervention. On multivariable analysis patients undergoing CEA with proximal CCA endovascular intervention experienced greater risk for perioperative neurological ischemic event (aOR 2.03, 1.43-2.90, P <.001), combined perioperative neurological ischemic event and 90 day mortality (aOR 2.13, 1.62-2.80, P <.001), long term mortality (HR 1.62, 1.12-2.29, P <.001), and cumulative neurological ischemic event in long term follow up (HR 1.62, 1.12-2.29, P =.007). Amongst 4395 cumulative ischemic neurological events in all study patients, 34% were TIA. Conclusions: Carotid bifurcation endarterectomy in combination with proximal endovascular common carotid artery intervention caries an over two fold higher perioperative risk of neurologic ischemic event and 90 day mortality relative to CEA in isolation for asymptomatic and symptomatic cohorts respectively. After surgery, freedom from cerebral ischemia and mortality for patients undergoing dual intervention is closely aligned with patients undergoing CEA in isolation. Despite high adverse perioperative event rates for the combined CEA and CCA treatment, there is likely long term stroke reduction and mortality benefit to this approach in symptomatic patients based on the event free rates seen herein after initial hospital discharge. The benefit of treating asymptomatic tandem ICA and CCA lesions remains vague but the 4.4% perioperative neurologic event and death rate suggests that these patients would be better managed with medical therapy. [ABSTRACT FROM AUTHOR]

We develop a class of new multivariate procedures for monitoring quality by detecting a change in the level of a multivariate process. Following the ideas of S.N. Roy, we first consider a linear combination statistic which results from projecting the multivariate observations onto a unit vector and then maximizing a selected univariate statistic over all directions. An application to a sheet metal assembly process is discussed in Section 3. Comparisons are made between one of our new procedures and other major multivariate quality monitoring schemes in Section 4. A small simulation study compares the average run lengths of the different procedures both when the process is in-control and after a shift has occurred. Some large sample properties are discussed in Section 5 and some computational details in Section 6. [Copyright &y& Elsevier]