Faculty Bibliography

AIM/OBJECTIVE:To investigate how psychosocial stress contributes to accelerated thrombosis, focusing on platelet activation and hyperreactivity. The specific objective was to identify novel platelet regulators involved in stress-mediated thrombosis, with a particular emphasis on the tetraspanin CD37. METHODS AND RESULTS/RESULTS:To explore how stress contributes to platelet hyperreactivity, platelets were isolated from (1) mice that experienced chronic variable stress and stress-free controls (n=8/group) and (2) human subjects with self-reported high and no stress levels (n=18/group), followed by RNA-sequencing. By comparing mutually expressed transcripts, a subset of genes differentially expressed following psychosocial stress was identified in both human and mouse platelets. In both mice and humans, platelet CD37 positively associates with platelet aggregation responses that underlie thrombosis, with Cd37-/- platelets exhibiting impaired integrin αIIbβ3 signaling, characterized by reduced platelet fibrinogen spreading and decreased agonist-induced αIIbβ3 activation. Consistent with a role for CD37 in regulating platelet activation responses, chimeric mice that received Cd37-/- bone marrow experienced a significantly increased time to vessel occlusion in the carotid artery FeCl3 model compared to mice reconstituted with wild-type bone marrow. CD37 deficiency did not alter hemostasis, as platelet count, coagulation metrics, prothrombin time, and partial thromboplastin time did not differ in Cd37-/- mice relative to wild-type mice. Consistent with this, bleeding time did not differ between wild-type and Cd37-/- mice following tail tip transection. CONCLUSIONS:This study provides new insights into the platelet-associated mechanisms underlying stress-mediated thrombosis. Identifying CD37 as a novel regulator of platelet activation responses offers potential therapeutic targets for reducing the thrombotic risk associated with psychosocial stress. The findings also contribute to understanding how psychosocial stress accelerates thrombotic events and underscore the importance of platelet activation in this process.

Although platelets play a critical pathogenic role in myocardial infarction (MI), few studies have characterized the MI platelet transcriptome in the acute or chronic setting in women. We report that transcripts associated with the actin cytoskeleton, Rho family GTPases, mitochondrial dysfunction, and inflammatory signaling are enriched in platelets from MI patients in the acute setting (n = 40, MI; n = 38, control) and do not significantly change over time. Furthermore, 79 platelet genes chronically elevated or suppressed after MI are associated with future cardiovascular events in an independent high-risk cohort (n = 135). Compared with women with MI with nonobstructive coronary arteries, platelets from women with MI and obstructive coronary artery disease were enriched in neutrophil activation and proinflammatory signaling pathways driven by increased tumor necrosis factor (TNF)-α signaling. Hierarchic clustering of the MI transcriptomic profile identified 3 subgroups with distinctive biological pathways and MI correlates. Our data demonstrate that platelets from MI patients are phenotypically different from MI-naïve patients in the acute and chronic settings and reveal a platelet transcriptomic signature with distinct clinical features.

BACKGROUND:Randomized trials of chronic total occlusion (CTO) revascularization vs medical therapy have yielded inconsistent results. OBJECTIVES/OBJECTIVE:The aim of this study was to evaluate outcomes with an initial invasive strategy (INV) vs an initial conservative strategy (CON) in patients with coronary computed tomographic angiography (CCTA)-determined CTO in the ISCHEMIA (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches) trial. METHODS:Participants in ISCHEMIA who underwent CCTA evaluated for CTO by the core laboratory (3,113 of 5,179 randomized patients [60%]) were categorized into subgroups with (100% stenosis) and without (<100% stenosis) CTO. Primary analysis compared outcomes in those randomized to INV vs CON using an intention-to-treat approach. Secondary analyses compared outcomes using inverse probability weighting to model successful CTO revascularization (REV) in all INV participants vs CON participants. RESULTS:Of the 3,113 CCTA-evaluable participants, 1,470 had at least 1 CTO (752 INV and 718 CON). INV did not reduce cardiovascular (CV) death or myocardial infarction (MI) (5-year difference -3.5%; 95% CI: -7.8% to 0.8%) and resulted in more procedural MIs (2.5%; 95% CI: 1.0%-4.0%) but fewer spontaneous MIs (-6.3%; 95% CI: -9.7% to -3.2%) than CON. CTO REV modeled across INV had a high probability (>90%) of any lower CV death or MI, MI, spontaneous MI, unstable angina, and heart failure counterbalanced by a higher rate of procedural MI. CTO REV significantly improved angina-related quality of life (mean difference 4.6 points), Rose Dyspnea Scale score (rescaled) (mean difference 5.3 points), and EQ-5D visual analog scale score (4.6 points). CONCLUSIONS:In the ISCHEMIA trial, the risks and benefits of INV compared with CON were similar among patients with and without CCTA-determined CTO (more frequent procedural MI, less frequent spontaneous MI, and significantly improved angina and dyspnea-related quality of life). In an observational comparison, successful CTO REV was associated with a high probability of lower CV death or MI (driven by lower MI) compared with CON. (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches [ISCHEMIA]; NCT01471522).

BACKGROUND:This study examined stress echocardiography (SE) in relation to coronary artery anatomy, and outcome in subjects randomized in the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) Trial. METHODS:Of 5,179 patients randomized to initial invasive or conservative strategy, SE was performed in 1,079. Coronary computed tomographic angiogram (CCTA) excluded left main disease and quantified coronary lesions. Degree of ischemia was defined by number of segments with stress-induced wall motion abnormalities (WMA) (mild < 3, moderate = 3 and severe > 3). Transient ischemic dilation (TID) was defined as a 10% increase in stress left ventricular (LV) end systolic volume. Primary end point was a composite of cardiovascular death (CVD), nonfatal myocardial infarction (MI), or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. RESULTS:On CCTA, 607/715 (84%) with CCTA evaluable for ≥70% lesion had one such lesion. Features associated with coronary lesions ≥ 70% were number of ischemic/infarcted segments, 3 or more ischemic segments in the anterior territory and inability to augment LV ejection fraction 10 percentage points . TID, present in 28.5%, was significantly associated with severity of ischemia. For every 0.10 increase in peak wall motion score index (WMSI), there was 12% increased risk of CVD or MI (adjusted HR=1.12 (95% CI: 1.04, 1.21), p=0.003. CONCLUSION/CONCLUSIONS:In patients with chronic coronary disease and moderate or severe myocardial ischemia receiving contemporary therapies, stress echocardiography identified subjects with significant CAD and WMSI provided prognostic value.

BACKGROUND:Women with chronic coronary disease have more frequent angina and worse health status than men, despite having less coronary artery disease (CAD). We examined whether perceived stress and depressive symptoms mediate sex differences in angina, and whether this relationship differs in the setting of obstructive CAD or ischemia with no obstructive coronary artery disease (INOCA). METHODS:We analyzed the association between sex, stress (Perceived Stress Scale-4) and depressive symptoms (Patient Health Questionnaire-8) on angina-related health status (Seattle Angina Questionnaire [SAQ]) at enrollment in the ISCHEMIA (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches) trial and CIAO-ISCHEMIA (Changes in Ischemia and Angina Over 1 Year Among ISCHEMIA Trial Screen Failures With No Obstructive CAD on Coronary CT [Computed Tomography] Angiography) ancillary study. RESULTS:=0.012). Higher stress and depressive symptoms were associated with worse angina in both cohorts. Female sex, Perceived Stress Scale-4 score, and Patient Health Questionnaire-8 score were each independently associated with lower SAQ summary score, but CAD versus INOCA cohort was not. There was no interaction between sex and stress (-0.39 [95% CI, -1.01 to 0.23]) or sex and depression (-0.00 [95% CI, -0.53 to 0.53]) on SAQ summary score. CONCLUSIONS:High stress and depressive symptoms were independently associated with worse angina and poorer health status, without interaction with sex with or without obstructive CAD. Factors other than stress or depression contribute to worse health status in women with obstructive CAD or INOCA. REGISTRATION/BACKGROUND:URL: https://www.clinicaltrials.gov; Unique identifiers: NCT02347215, NCT01471522.

Cardiogenic shock (CS) is critical end-organ hypoperfusion attributable to reduced cardiac output. Acute ST-segment-elevation myocardial infarction with CS (AMI-CS) has high mortality. Clinical research is challenging in such patients as they often cannot provide consent, lack available legal representatives, and require initiation of therapy. Multiple trials have enrolled patients with AMI-CS outside the United States under deferred consent. Trials in the United States have enrolled patients with out-of-hospital cardiac arrest under exception from informed consent (EFIC). However, AMI-CS has a longer therapeutic window to initiate treatment than out-of-hospital cardiac arrest, and more patients or their representatives can engage in treatment decisions. We provide a rationale for how a trial enrolling patients with AMI-CS could qualify for conduct using EFIC by meeting each criterion specified in US human subject regulations. AMI-CS is a life-threatening situation, available treatments are unsatisfactory, and collection of valid evidence is necessary. Obtaining informed consent is often not feasible, and trial participation could benefit subjects. Only enrolling consented patients is impracticable and could reduce the study's generalizability. We propose a therapeutic window of 30 minutes within the study intervention must be initiated, with consent sought within 15 minutes, respecting any refusal or objection to enrollment, and otherwise enrollment under EFIC. A trial could enroll patients with AMI-CS under EFIC and can involve both patients and their representatives. Successful use of EFIC in trials of other interventions in patients with CS or enrolling patients with other acute cardiovascular conditions could increase the available evidence base to improve care.

BACKGROUND/UNASSIGNED:The appropriate use criteria for revascularization of stable ischemic heart disease have not been evaluated using randomized data. Using data from the randomized ISCHEMIA trial (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches; July 2012 to January 2018, 37 countries), the health status benefits of an invasive strategy over a conservative one were examined within appropriate use criteria scenarios. METHODS/UNASSIGNED:Among 1833 participants mapped to 36 appropriate use criteria scenarios, symptom status was assessed using the Seattle Angina Questionnaire-7 at 1 year for each scenario and for each of the 6 patient characteristics used to define the scenarios. Coronary anatomy and SYNTAX(Synergy between percutaneous coronary intervention with Taxus and cardiac surgery) scores were measured using coronary computed tomography angiography. Treatment effects are expressed as an odds ratio for a better health status outcome with an invasive versus conservative treatment strategy using Bayesian hierarchical proportional odds models. Differences in the primary clinical outcome were similarly examined. RESULTS/UNASSIGNED:The mean age was 63 years, 81% were male, and 71% were White. Diabetes was present in 28% and multivessel disease in 51%. Most clinical scenarios favored invasive for better 1-year health status. The benefit of an invasive strategy on Seattle Angina Questionnaire angina frequency scores was reduced for asymptomatic patients (odds ratio [95% credible interval], 1.16 [0.66-1.71] versus 2.26 [1.75-2.80]), as well as for those on no antianginal medications. Diabetes, number of diseased vessels, proximal left anterior descending coronary artery location, and SYNTAX score did not effectively identify patients with better health status after invasive treatment, and minimal differences in clinical events were observed. CONCLUSIONS/UNASSIGNED:Applying the randomization scheme from the ISCHEMIA trial to appropriate clinical scenarios revealed baseline symptoms and antianginal therapy to be the primary drivers of health status benefits from invasive management. Consideration should be given to reducing the patient characteristics collected to generate appropriateness ratings to improve the feasibility of future data collection. REGISTRATION/UNASSIGNED:URL: https://www.clinicaltrials.gov; Unique identifier: NCT01471522.

BACKGROUND/UNASSIGNED:Elevated perceived stress is associated with adverse outcomes following myocardial infarction (MI) and may account for poorer recovery among women vs men. OBJECTIVES/UNASSIGNED:This randomized controlled trial tested effects of a mindfulness-based intervention on stress levels among women with MI. METHODS/UNASSIGNED:Women with elevated stress (Perceived Stress Scale [PSS-4]≥6) at least 2 months after MI were enrolled from 12 hospitals in the United States and Canada and via community advertising. Participants were randomized to a remotely delivered mindfulness intervention (MBCT-Brief) or heart disease education, both 8 weeks long. Follow-up was 6 months. Changes in stress (PSS-10; primary outcome) and secondary outcomes (depressive symptoms, anxiety, quality of life, disease-specific health status, actigraphy-assessed sleep) were compared between groups. RESULTS/UNASSIGNED: = 0.036). CONCLUSIONS/UNASSIGNED:MBCT-Brief was associated with greater 6-month reductions in stress than an active control among adherent participants. More frequent mindfulness practice was associated with greater improvements in psychological outcomes. Strategies to engage women with MI in mindfulness training and support regular home practice may enhance these effects.

BACKGROUND/UNASSIGNED:Reported results of clinical trials assessing higher-dose anticoagulation in patients hospitalized for COVID-19 have been inconsistent. PURPOSE/UNASSIGNED:To estimate the association of higher- versus lower-dose anticoagulation with clinical outcomes. DATA SOURCES/UNASSIGNED:Randomized trials were identified from the World Health Organization's International Clinical Trials Registry Platform and ClinicalTrials.gov with no restriction by trial status or language. STUDY SELECTION/UNASSIGNED:Eligible randomized trials assigned patients hospitalized for COVID-19 to higher- versus lower-dose anticoagulation. DATA EXTRACTION/UNASSIGNED:20 eligible trials provided data in a prospectively agreed format. Two further studies were included based on published data. The primary outcome was all-cause mortality 28 days after randomization. Secondary outcomes were progression to invasive mechanical ventilation or death, thromboembolic events, and major bleeding. DATA SYNTHESIS/UNASSIGNED: = 0%; 10 trials, 3897 patients, 2935 receiving no or low oxygen at randomization) for intermediate- versus prophylactic-dose anticoagulation. Treatment effects appeared broadly consistent across predefined patient subgroups, although some analyses were limited in power. Higher- compared with lower-dose anticoagulation was associated with fewer thromboembolic events, but a greater risk for major bleeding. CONCLUSION/UNASSIGNED:Therapeutic-dose compared with prophylactic-dose anticoagulation reduced 28-day mortality. Mortality was similar for intermediate-dose compared with prophylactic-dose anticoagulation and higher for therapeutic-dose compared with intermediate-dose anticoagulation, although this comparison was not estimated precisely. PRIMARY FUNDING SOURCE/UNASSIGNED:No direct funding. (PROSPERO: CRD42020213461).