Faculty Bibliography

BACKGROUND:Rates and predictors of major bleeding in patients with peripheral artery disease (PAD) treated with antiplatelets have not been well studied. This post hoc analysis of EUCLID aimed to determine the incidence of major/minor bleeding, predictors of major bleeding, and risk of major adverse cardiovascular events (MACE) following major bleeding events. METHODS:EUCLID, a multicenter randomized controlled trial of 13,885 patients with symptomatic PAD, compared ticagrelor with clopidogrel for the prevention of MACE. The primary safety end point was Thrombolysis in Myocardial Infarction (TIMI) major bleeding. Baseline characteristics were used to develop a multivariable model to determine factors associated with TIMI major bleeding. The occurrence and timing of MACE relative to a first major bleeding event were determined. RESULTS:TIMI major bleeding occurred in 2.3% of participants overall (0.94 event/100 patient-years). There was no significant difference in major bleeding rates by treatment assignment. Factors associated with TIMI major bleeding included older age, geographic region, Rutherford class, and β-blocker use. Patients with TIMI major bleeding postrandomization had an increased risk of MACE (hazard ratio [HR] 4.46; 95% CI 3.40-5.84; P < .0001) compared with those without major bleeding; the association was strongest within 30 days after a bleeding event. CONCLUSIONS:In patients with symptomatic PAD, 0.94 major bleeding event/100 patient-years was observed and associated with older age, residing in North America, disease severity, and β-blocker use. Patients who had a major bleeding event were significantly more likely to experience MACE, especially within the first 30 days, when compared with patients who did not have major bleeding.

BACKGROUND AND AIMS/OBJECTIVE:An independent association of body mass index (BMI) with atherosclerotic cardiovascular disease is somewhat controversial and may differ by vascular bed. Sex-specific risk factors for atherosclerosis may further modify these associations. Obesity and peripheral artery disease (PAD) are both more prevalent in women. We sought to determine the association between PAD and BMI using a very large population-based study. METHODS:Self-referred individuals at >20,000 US sites completed medical questionnaires including height and weight, and were evaluated by screening ankle brachial indices (ABI) for PAD (ABI<0.9). RESULTS:). CONCLUSIONS:Our study suggests that increasing BMI is a robust independent risk factor for PAD only in women. This observation requires validation, but highlights the need for further research on sex-specific risk and mechanisms of atherosclerosis.

BACKGROUND:The relationship between invasive vascular procedures and bleeding in patients with peripheral artery disease has not been well described in the literature. This post hoc analysis from the EUCLID trial (Examining Use of Ticagrelor in Peripheral Artery Disease) aimed to describe the incidence of major and minor postprocedural bleeding and characterize the timing and severity of bleeding events relative to the procedure. METHODS:EUCLID was a multicenter, randomized controlled trial of 13 885 patients with symptomatic peripheral artery disease that tested the efficacy and safety of ticagrelor compared with clopidogrel for the prevention of major adverse cardiovascular events. A total of 2661 patients underwent 3062 coronary revascularization, peripheral revascularization, and amputation during the study. The primary safety end point was Thrombolysis in Myocardial Infarction major or minor bleeding. All bleeding events were formally adjudicated by a clinical end point classification group. RESULTS:Major bleeding events most often occurred ≤7 days following the procedure. The incidence of Thrombolysis in Myocardial Infarction major or minor bleeding ≤7 days following peripheral revascularization (3.3%; 95% CI, 2.5%-4.1%) was similar to rates after coronary revascularization (4.0%; 95% CI, 2.6%-5.4%) and lower extremity amputation (2.3%; 95% CI, 0.8%-3.8%). The severity of bleeding events (as graded by drop in hemoglobin, need for transfusion, bleeding in a critical location, and fatal bleeding) was also similar following peripheral, coronary revascularization, and lower extremity amputation. CONCLUSIONS:The incidence of Thrombolysis in Myocardial Infarction major/minor bleeding following peripheral revascularization is comparable to rates after coronary revascularization and lower extremity amputation, and the majority of bleeding events occur within 7 days following the procedure. The severity of periprocedural bleeding is also similar after procedures, with the most frequently adjudicated reason being a drop in hemoglobin ≥2 g/dL. Future studies should be performed to enhance our understanding of bleeding risk related to revascularization and amputation procedures in peripheral artery disease patients.

Platelets are best known as mediators of hemostasis and thrombosis; however, their inflammatory effector properties are increasingly recognized. Atherosclerosis, a chronic vascular inflammatory disease, represents the interplay between lipid deposition in the artery wall and unresolved inflammation. Here, we reveal that platelets induce monocyte migration and recruitment into atherosclerotic plaques, resulting in plaque platelet-macrophage aggregates. In Ldlr^-/- mice fed a Western diet, platelet depletion decreased plaque size and necrotic area and attenuated macrophage accumulation. Platelets drive atherogenesis by skewing plaque macrophages to an inflammatory phenotype, increasing myeloid suppressor of cytokine signaling 3 (SOCS3) expression and reducing the Socs1:Socs3 ratio. Platelet-induced Socs3 expression regulates plaque macrophage reprogramming by promoting inflammatory cytokine production (Il6, Il1b, and Tnfa) and impairing phagocytic capacity, dysfunctions that contribute to unresolved inflammation and sustained plaque growth. Translating our data to humans with cardiovascular disease, we found that women with, versus without, myocardial infarction have up-regulation of SOCS3, lower SOCS1:SOCS3, and increased monocyte-platelet aggregate. A second cohort of patients with lower extremity atherosclerosis demonstrated that SOCS3 and the SOCS1:SOCS3 ratio correlated with platelet activity and inflammation. Collectively, these data provide a causative link between platelet-mediated myeloid inflammation and dysfunction, SOCS3, and cardiovascular disease. Our findings define an atherogenic role of platelets and highlight how, in the absence of thrombosis, platelets contribute to inflammation.

BACKGROUND:Despite robust cholesterol lowering, cardiovascular disease risk remains increased in patients with diabetes mellitus. Consistent with this, diabetes mellitus impairs atherosclerosis regression after cholesterol lowering in humans and mice. In mice, this is attributed in part to hyperglycemia-induced monocytosis, which increases monocyte entry into plaques despite cholesterol lowering. In addition, diabetes mellitus skews plaque macrophages toward an atherogenic inflammatory M1 phenotype instead of toward the atherosclerosis-resolving M2 state typical with cholesterol lowering. Functional high-density lipoprotein (HDL), typically low in patients with diabetes mellitus, reduces monocyte precursor proliferation in murine bone marrow and has anti-inflammatory effects on human and murine macrophages. Our study aimed to test whether raising functional HDL levels in diabetic mice prevents monocytosis, reduces the quantity and inflammation of plaque macrophages, and enhances atherosclerosis regression after cholesterol lowering. METHODS:mice were transplanted into either wild-type, diabetic wild-type, or diabetic mice transgenic for human apolipoprotein AI, which have elevated functional HDL. Recipient mice all had low levels of low-density lipoprotein cholesterol to promote plaque regression. After 2 weeks, plaques in recipient mouse aortic grafts were examined. RESULTS:Diabetic wild-type mice had impaired atherosclerosis regression, which was normalized by raising HDL levels. This benefit was linked to suppressed hyperglycemia-driven myelopoiesis, monocytosis, and neutrophilia. Increased HDL improved cholesterol efflux from bone marrow progenitors, suppressing their proliferation and monocyte and neutrophil production capacity. In addition to reducing circulating monocytes available for recruitment into plaques, in the diabetic milieu, HDL suppressed the general recruitability of monocytes to inflammatory sites and promoted plaque macrophage polarization to the M2, atherosclerosis-resolving state. There was also a decrease in plaque neutrophil extracellular traps, which are atherogenic and increased by diabetes mellitus. CONCLUSIONS:Raising apolipoprotein AI and functional levels of HDL promotes multiple favorable changes in the production of monocytes and neutrophils and in the inflammatory environment of atherosclerotic plaques of diabetic mice after cholesterol lowering and may represent a novel approach to reduce cardiovascular disease risk in people with diabetes mellitus.

BACKGROUND:Prior registry data suggest that 4%-20% of patients require noncardiac surgery (NCS) within 2 years of percutaneous coronary intervention (PCI). Contemporary data on NCS after PCI in the United States among women and men are limited. We determined the rate of early hospital readmission for NCS and associated outcomes in a large cohort of patients who underwent PCI in the United States. METHODS:Adults undergoing PCI between January 1 and June 30, 2014, were identified from the Nationwide Readmission Database. Patients readmitted for NCS within 6 months of PCI were identified. Outcomes of interest were in-hospital death, myocardial infarction (MI), and bleeding defined by International Classification of Diseases, Ninth Revision, codes. RESULTS:Among 221,379 patients who underwent PCI and survived to hospital discharge, 3.5% (n = 7,696) were readmitted for NCS within 6 months post-PCI, and 41% of these hospitalizations were elective. Early NCS was complicated by MI in 4.7% of cases, and 21% of perioperative MIs were fatal. Bleeding was recorded in 32.0% of patients. All-cause mortality occurred in 4.4% of patients (n = 339) readmitted for surgery. The risk of death or MI was greatest when NCS was performed within the first month after PCI. CONCLUSIONS:Despite clear guidelines to avoid surgery early after PCI, NCS was performed in 1 of every 29 patients with recent PCI, corresponding to as many as ~30,000 patients each year nationwide. Surgical mortality and perioperative MI were high in this setting. Strategies to minimize perioperative thrombotic and bleeding risks during readmission for NCS after PCI are necessary.

Stroke is a serious complication of noncardiac surgery. Congenital defects of the interatrial septum may be a potent risk factor for perioperative stroke. The aim of the present study was to determine the association between atrial septal defect (ASD) or patent foramen ovale (PFO) and in-hospital perioperative ischemic stroke after non-cardiac surgery in a large nationwide cohort of patients hospitalized in the United States. Patients undergoing noncardiac surgery between 2004 and 2014 were identified using the Healthcare Cost and Utilization Project's National Inpatient Sample. Patients without an in-hospital echocardiogram were excluded. The presence of an ostium secundum-type ASD or PFO was identified by ICD-9 diagnosis code 745.5. The primary study outcome was perioperative acute ischemic stroke. Between 2004 and 2014, there were 639,985 admissions for noncardiac surgery with an in-hospital echocardiogram. An ASD or PFO was documented in 9,041 (1.4%) hospitalizations. Perioperative ischemic stroke occurred more frequently in patients with an ASD or PFO compared with those without an ASD or PFO (35.1% vs 6.0%, p <0.001). The association between ASD or PFO and ischemic stroke persisted after adjustment for demographics and clinical covariates (adjusted odds ratio 6.30, 95% confidence interval, 5.59 to 7.10) and in all non-cardiac surgery subtypes. In conclusion, in a large, nationwide analysis of patients undergoing noncardiac surgery, a diagnosis of ASD or PFO was associated with an increased risk of acute ischemic stroke overall and in all surgical subtypes. Additional measures are necessary to mitigate stroke risk in patients with septal defects who are planned for non-cardiac surgery.