Total Cardiovascular and Limb Events and the Impact of Polyvascular Disease in Chronic Symptomatic Peripheral Artery Disease.

Background Peripheral artery disease (PAD) is associated with heightened risk for major adverse cardiovascular and limb events, but data on the burden of risk for total (first and potentially subsequent) events, and the association with polyvascular disease, are limited. This post hoc analysis of the EUCLID (Examining Use of Ticagrelor in Peripheral Artery Disease) trial evaluated total cardiovascular and limb events among patients with symptomatic PAD, overall and by number of symptomatic vascular territories. Methods and Results In the EUCLID trial, patients with symptomatic PAD (lower extremity revascularization >30 days before randomization or ankle-brachial index ≤0.80) were randomized to treatment with ticagrelor or clopidogrel. Relative effects on total events (cardiovascular death; nonfatal myocardial infarction and ischemic stroke; acute limb ischemia, unstable angina, and transient ischemic attack requiring hospitalization; coronary, carotid, and peripheral revascularization procedures; and amputation for symptomatic PAD) were summarized by hazard ratios (HRs), whereas absolute risks were estimated by incidence rates and mean cumulative functions. Among 13 885 randomized patients, 7600 total cardiovascular and limb events occurred during a median 2.7 years of follow-up, translating to 60.0 and 62.5 events per 100 patients through 3 years for the ticagrelor and clopidogrel groups, respectively (HR, 0.96; 95% CI, 0.89-1.03; P=0.27). Among 1393 patients with disease in 3 vascular territories, event accrual rates through 3 years for the ticagrelor and clopidogrel groups were 87.3 and 97.7 events per 100 patients, respectively. Absolute risk reductions for ticagrelor relative to clopidogrel at 3 years were -0.2, 6.7, and 10.3 events per 100 patients for 1, 2, and 3 affected vascular territories, respectively (Pinteraction=0.09). Conclusions Patients with symptomatic PAD have nearly double the number of total events than first events, with rates reflecting the number of affected vascular territories. These findings highlight the clinical relevance of quantifying disease burden in terms of total events and the need for long-term preventive treatments in high-risk patient populations. Registration URL: https://clinicaltrials.gov/; Unique identifier: NCT01732822

Total Cardiovascular and Limb Events and the Impact of Polyvascular Disease in Chronic Symptomatic Peripheral Artery Disease

BACKGROUND: Peripheral artery disease (PAD) is associated with heightened risk for major adverse cardiovascular and limb events, but data on the burden of risk for total (first and potentially subsequent) events, and the association with polyvascular disease, are limited. This post hoc analysis of the EUCLID (Examining Use of Ticagrelor in Peripheral Artery Disease) trial evaluated total cardiovascular and limb events among patients with symptomatic PAD, overall and by number of symptomatic vascular territories.METHODS AND RESULTS: In the EUCLID trial, patients with symptomatic PAD (lower extremity revascularization >30 days before randomization or ankle-brachial index CONCLUSIONS: Patients with symptomatic PAD have nearly double the number of total events than first events, with rates reflecting the number of affected vascular territories. These findings highlight the clinical relevance of quantifying disease burden in terms of total events and the need for long-term preventive treatments in high-risk patient populations.</p

Complexity, Interation, and Epistemology: Mixtecs, Zapotecs, and Olmecs in Early Formative Mesoamerica

Interaction between the Gulf Coast Olmecs and various regions of Early Formative Mesoamerica remains debated and poorly understood. In Oaxaca, models have been dominated by neoevolutionary epistemology; interaction between the Valley of Oaxaca and San Lorenzo has been characterized by emulation or peer polity models. Data from the Valley of Oaxaca, the Nochixtlán Valley, and the Gulf Coast demonstrate that San Lorenzo was at a different level of sociopolitical complexity than its contemporaries. Previous comparisons between Olmec-style pottery in the Gulf Coast and Valley of Oaxaca are found to be problematic, and have led to the impression that Oaxaca villagers produced more of this pottery than did the Olmecs. Neutron activation analysis demonstrates the Gulf Coast Olmecs exported ceramics to Mixtecs and Zapotecs in Oaxaca, while receiving few if any pots in return, suggesting that new models and theoretical perspectives must be applied to understanding the relationships between Oaxacan chiefdoms and the nascent Olmec state at San Lorenzo. An agency perspective explores what Mixtec, Zapotec, and Olmec groups may have taken from these interactions and relationships and acknowledges both local and Gulf Coast understandings of “Olmec.” Such relationships may be characterized more by acquisition between regions, with San Lorenzo as a superordinate center

Impact of chronic kidney disease on hemoglobin among patients with peripheral artery disease treated with P2Y12 inhibitors: Insights from the EUCLID trial.

Patients with chronic kidney disease may develop new or more severe anemia when treated with antiplatelet agents due to blood loss in conjunction with impaired erythropoiesis. Because anemia independently predicts limb amputation and mortality among patients with peripheral artery disease (PAD), we evaluated the relationship between estimated glomerular filtration rate (eGFR) and hemoglobin (Hb) levels in the EUCLID trial in which patients with symptomatic PAD were randomized to ticagrelor or clopidogrel. At baseline, 9025, 1870, and 1000 patients had eGFR ⩾ 60, 45-59, and < 45 mL/min/1.73 m2, respectively. The mean fall in Hb during the trial was 0.46 ± 1.68 g/dL and did not differ by baseline eGFR category, although Hb fall ⩾ 10% was more frequent among patients with lower eGFR (p for trend < 0.0001). On-study treatment with iron, erythropoiesis-stimulating agents, and/or red blood cell transfusion was reported for 479 (5.3%), 165 (8.8%), and 129 (12.9%) patients in the three eGFR categories, respectively (p for trend < 0.0001). After adjustment for baseline and post-randomization effects, those not receiving anemia treatment had a smaller reduction in Hb from baseline than those receiving anemia treatment (p < 0.0001). Other determinants of Hb reduction included absence of on-study myocardial infarction, coronary or peripheral revascularization, residence outside North America, male sex, and baseline eGFR. We conclude that among patients with PAD treated with P2Y12 inhibitors, lower baseline eGFR was associated with a greater reduction in Hb. ClinicalTrials.gov Identifier: NCT01732822

Ankle-Brachial Index for Risk Stratification in Patients With Symptomatic Peripheral Artery Disease With and Without Prior Lower Extremity Revascularization: Observations From the EUCLID Trial.

Background: A reduced ankle-brachial index (ABI) is a measure of atherosclerosis and is associated with ischemic risk in the general population. Whether this relationship is maintained in peripheral artery disease after lower extremity revascularization (LER), which can modify ABI, is unknown. Methods: The EUCLID (Examining Use of Ticagrelor in Peripheral Artery Disease) enrolled 13 885 patients with symptomatic peripheral artery disease; 57% with prior LER, and 43% with ABI ≤0.80. The primary major adverse cardiovascular events (MACE) outcome was a composite of cardiovascular death, myocardial infarction, or ischemic stroke. Major adverse limb events (MALE) included acute limb ischemia and major amputation. An adjusted Cox proportional hazards model demonstrated a nonlinear relationship between ABI and outcomes. A restricted cubic spline model with 4 knots was developed to identify the best fitting model to describe the relationship between ABI and MACE and MALE risk. Results: Baseline ABI (mean±SD) was 0.77±0.21 in participants with prior LER and 0.63±0.14 in those without prior LER (P<0.0001). There was no statistical interaction between prior LER and ABI, meaning the shapes of the cubic spline models were similar between groups. In those with prior LER, for every 0.10 unit lower ABI below an ABI of 1.00, the hazard ratio for MACE was 1.08 (95% CI, 1.04–1.12; P<0.0001), below an ABI of 0.80 the hazard ratio for MALE was 1.32 (95% CI, 1.21–1.43; P<0.0001). In patients without prior LER, every 0.10 unit lower ABI below an ABI of 0.70 was associated with increased risk for MACE (hazard ratio, 1.14 [95% CI, 1.06–1.23]; P=0.0004) and MALE (hazard ratio, 1.27 [95% CI, 1.08–1.49]; P=0.003). Conclusions: Patients with established peripheral artery disease, particularly those with prior LER, have an increased risk of MACE and MALE. The ABI remains a strong predictor of MACE and MALE ischemic events with an inverse relationship below an ABI threshold for patients with and without prior LER

Etiology and Outcomes of Amputation in Patients With Peripheral Artery Disease: Insights From the EUCLID Trial.

OBJECTIVE Amputation remains a frequent and feared outcome in patients with peripheral artery disease (PAD). Although typically characterized as major or minor on the extent of tissue loss, the etiologies and outcomes after amputation by extent are not well-understood. In addition, emerging data suggest that the drivers and outcomes of amputation in patients with PAD may differ in those with and without diabetes mellitus (DM). METHODS The EUCLID trial randomized 13,885 patients with symptomatic PAD, including 5345 with concomitant diabetes, to ticagrelor or clopidogrel and followed them for long-term outcomes. Amputations were prospectively reported by trial investigators. Their primary and contributing drivers were adjudicated using safety data, including infection, ischemia, or multifactorial etiologies. Outcomes following major and minor amputations were analyzed, including recurrent amputation, major adverse limb events, adverse cardiovascular events, and mortality. Multivariable logistic regression models were used to identify independent predictors of minor amputations. Analyses were performed overall and stratified by the presence or absence of DM at baseline. RESULTS Of the patients randomized, 398 (2.9%) underwent at least one lower extremity nontraumatic amputation, for a total of 511 amputations (255 major and 256 minor) over a median of 30 months. A history of minor amputation was the strongest independent predictor for a subsequent minor amputation (odds ratio, 7.29; 95% confidence interval, 5.17-10.30; P < .001) followed by comorbid DM (odds ratio, 4.60; 95% confidence interval, 3.16-6.69; P < .001). Compared with patients who had a major amputation, those with a minor amputation had similar rates of subsequent major amputation (12.2% vs 13.6%), major adverse limb events (15.1% vs 14.9%), and major adverse cardiovascular events (17.6% vs 16.3%). Ischemia alone was the primary driver of amputation (51%), followed by infection alone (27%), and multifactorial etiologies (22%); however, infection was the most frequent driver in those with DM (58%) but not in those without DM (15%). CONCLUSIONS Outcomes after amputation remain poor regardless of whether they are categorized as major or minor. The pattern of amputation drivers in PAD differs by history of DM, with infection being the dominant etiology in those with DM and ischemia in those without DM. Greater focus is needed on the prognostic importance of minor amputation and of the multifactorial etiologies of amputation in PAD. Nomenclature with anatomical description of amputations and eliminating terms "major" or "minor" would seem appropriate