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"Welsh, Robert C."
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A Controlled Trial of Rivaroxaban after Transcatheter Aortic-Valve Replacement
by
Makkar, Raj R
,
Giustino, Gennaro
,
Zazula, Ana
in
9NDF7JZ4M3 (Rivaroxaban)
,
A74586SNO7 (Clopidogrel)
,
Aged
2020
Patients who had undergone successful TAVR were randomly assigned to receive either a rivaroxaban-based antithrombotic regimen or an antiplatelet-based antithrombotic regimen. At 17 months, the primary outcome of death or thromboembolic complications occurred more frequently with rivaroxaban.
Journal Article
Resting-State Functional Connectivity between Fronto-Parietal and Default Mode Networks in Obsessive-Compulsive Disorder
2012
Obsessive-compulsive disorder (OCD) is characterized by an excessive focus on upsetting or disturbing thoughts, feelings, and images that are internally-generated. Internally-focused thought processes are subserved by the \"default mode network\" (DMN), which has been found to be hyperactive in OCD during cognitive tasks. In healthy individuals, disengagement from internally-focused thought processes may rely on interactions between DMN and a fronto-parietal network (FPN) associated with external attention and task execution. Altered connectivity between FPN and DMN may contribute to the dysfunctional behavior and brain activity found in OCD.
The current study examined interactions between FPN and DMN during rest in 30 patients with OCD (17 unmedicated) and 32 control subjects (17 unmedicated). Timecourses from seven fronto-parietal seeds were correlated across the whole brain and compared between groups.
OCD patients exhibited altered connectivity between FPN seeds (primarily anterior insula) and several regions of DMN including posterior cingulate cortex, medial frontal cortex, posterior inferior parietal lobule, and parahippocampus. These differences were driven largely by a reduction of negative correlations among patients compared to controls. Patients also showed greater positive connectivity between FPN and regions outside DMN, including thalamus, lateral frontal cortex, and somatosensory/motor regions.
OCD is associated with abnormal intrinsic functional connectivity between large-scale brain networks. Alteration of interactions between FPN and DMN at rest may contribute to aspects of the OCD phenotype, such as patients' inability to disengage from internally-generated scenarios and thoughts when performing everyday tasks requiring external attention.
Journal Article
Long-term risk of death and recurrent cardiovascular events following acute coronary syndromes
2021
Estimates of the risk of recurrent cardiovascular events (residual risk) among patients with acute coronary syndromes have largely been based on clinical trial populations. Our objective was to estimate the residual risk associated with common comorbidities in a large, unselected, population-based cohort of acute coronary syndrome patients. 31,056 ACS patients (49.5%—non-ST segment elevation myocardial infarction [NSTEMI], 34.0%—ST segment elevation myocardial infarction [STEMI] and 16.5%—unstable angina [UA]) hospitalised in Alberta between April 2010 and March 2016 were included. The primary composite outcome was major adverse cardiovascular events (MACE) including: death, stroke or recurrent myocardial infarction. The secondary outcome was death from any cause. Cox-proportional hazard models were used to identify the impact of ACS type and commonly observed comorbidities (heart failure, hypertension, peripheral vascular disease, renal disease, cerebrovascular disease and diabetes). At 3.0 +/- 3.7 years, rates of MACE were highest in the NSTEMI population followed by STEMI and UA (3.58, 2.41 and 1.68 per 10,000 person years respectively). Mortality was also highest in the NSTEMI population followed by STEMI and UA (2.23, 1.38 and 0.95 per 10,000 person years respectively). Increased burden of comorbidities was associated with an increased risk of MACE, most prominently seen with heart failure (adjusted HR 1.83; 95% CI 1.73–1.93), renal disease (adjusted HR 1.52; 95% CI 1.40–1.65) and diabetes (adjusted HR 1.51; 95% CI 1.44–1.59). The cumulative presence of each of examined comorbidities was associated with an incremental increase in the rate of MACE ranging from 1.7 to 9.98 per 10,000 person years. Rates of secondary prevention medications at discharge were high including: statin (89.5%), angiotensin converting enzyme inhibitor/angiotensin receptor blocker (84.1%) and beta-blockers (85.9%). Residual cardiovascular risk following an acute coronary syndrome remains high despite advances in secondary prevention. A higher burden of comorbidities is associated with increased residual risk that may benefit from aggressive or novel therapies.
Journal Article
Clinically significant bleeding with low-dose rivaroxaban versus aspirin, in addition to P2Y12 inhibition, in acute coronary syndromes (GEMINI-ACS-1): a double-blind, multicentre, randomised trial
by
Plotnikov, Alexei
,
Strony, John
,
Sun, Xiang
in
Acute Coronary Syndrome - drug therapy
,
Acute coronary syndromes
,
Adenosine - administration & dosage
2017
Dual antiplatelet therapy (DAPT), aspirin plus a P2Y12 inhibitor, is the standard antithrombotic treatment following acute coronary syndromes. The factor Xa inhibitor rivaroxaban reduced mortality and ischaemic events when added to DAPT, but caused increased bleeding. The safety of a dual pathway antithrombotic therapy approach combining low-dose rivaroxaban (in place of aspirin) with a P2Y12 inhibitor has not been assesssed in acute coronary syndromes. We aimed to assess rivaroxaban 2·5 mg twice daily versus aspirin 100 mg daily, in addition to clopidogrel or ticagrelor (chosen at investigator discretion before randomisation), for patients with acute coronary syndromes started within 10 days after presentation and continued for 6–12 months.
In this double-blind, multicentre, randomised trial (GEMINI-ACS-1) done at 371 clinical centres in 21 countries, eligible patients were older than 18 years with unstable angina, non-ST segment elevation myocardial infarction (NSTEMI) or ST segment elevation myocardial infarction (STEMI), with positive cardiac biomarkers and either ischaemic electrocardiographic changes or an atherosclerotic culprit lesion identified during angiography. Participants were randomly assigned (1:1) within 10 days after admission for the index acute coronary syndromes event to either aspirin or rivaroxaban based on a computer-generated randomisation schedule. Randomisation was balanced by using randomly permuted blocks with size of four and was stratified based on the background P2Y12 inhibitor (clopidogrel or ticagrelor) intended to be used at the time of randomisation. Investigators and patients were masked to treatment assignment. Patients received a minimum of 180 days of double-blind treatment with rivaroxaban 2·5 mg twice daily or aspirin 100 mg daily. The choice of clopidogrel or ticagrelor during trial conduct was not randomised and was based on investigator preference. The primary endpoint was thrombolysis in myocardial infarction (TIMI) clinically significant bleeding not related to coronary artery bypass grafting (CABG; major, minor, or requiring medical attention) up to day 390. Primary analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT02293395.
Between April 22, 2015, and Oct 14, 2016, 3037 patients with acute coronary syndromes were randomly assigned; 1518 to receive aspirin and 1519 to receive rivaroxaban. 1704 patients (56%) were in the ticagrelor and 1333 (44%) in the clopidogrel strata. Median duration of treatment was 291 days (IQR 239–354). TIMI non-CABG clinically significant bleeding was similar with rivaroxaban versus aspirin therapy (total 154 patients [5%]; 80 participants [5%] of 1519 vs 74 participants [5%] of 1518; HR 1·09 [95% CI 0·80–1·50]; p=0·5840).
A dual pathway antithrombotic therapy approach combining low-dose rivaroxaban with a P2Y12 inhibitor for the treatment of patients with acute coronary syndromes had similar risk of clinically significant bleeding as aspirin and a P2Y12 inhibitor. A larger, adequately powered trial would be required to definitively assess the efficacy and safety of this approach.
Janssen Research & Development and Bayer AG.
Journal Article
Fibrinolysis or Primary PCI in ST-Segment Elevation Myocardial Infarction
by
Van de Werf, Frans
,
Welsh, Robert C
,
Rosell Ortiz, Fernando
in
Aged
,
Angiography
,
Angioplasty, Balloon, Coronary
2013
Reperfusion strategies with fibrinolysis or primary PCI were compared in this trial involving patients with ST-segment elevation myocardial infarction (STEMI). The two methods had similar efficacy, but there was more intracranial bleeding in the fibrinolysis group.
Although contemporary guidelines for patients with acute ST-segment elevation myocardial infarction (STEMI) recommend primary percutaneous coronary intervention (PCI) as the preferred reperfusion strategy, this approach is contingent on performing PCI in a timely fashion.
1
,
2
Since most patients do not present to a PCI-capable hospital, this factor presents a major logistic challenge in many regions.
3
Despite substantial effort directed toward addressing this issue, the large majority of patients with STEMI who present to non-PCI facilities do not subsequently receive primary PCI within guideline-recommended times.
4
This delay results in a commensurate increase in morbidity and mortality.
5
,
6
A second major therapeutic . . .
Journal Article
Outcomes after thrombus aspiration for ST elevation myocardial infarction: 1-year follow-up of the prospective randomised TOTAL trial
2016
Two large trials have reported contradictory results at 1 year after thrombus aspiration in ST elevation myocardial infarction (STEMI). In a 1-year follow-up of the largest randomised trial of thrombus aspiration, we aimed to clarify the longer-term benefits, to help guide clinical practice.
The trial of routine aspiration ThrOmbecTomy with PCI versus PCI ALone in Patients with STEMI (TOTAL) was a prospective, randomised, investigator-initiated trial of routine manual thrombectomy versus percutaneous coronary intervention (PCI) alone in 10 732 patients with STEMI. Eligible adult patients (aged ≥18 years) from 87 hospitals in 20 countries were enrolled and randomly assigned (1:1) within 12 h of symptom onset to receive routine manual thrombectomy with PCI or PCI alone. Permuted block randomisation (with variable block size) was done by a 24 h computerised central system, and was stratified by centre. Participants and investigators were not masked to treatment assignment. The trial did not show a difference at 180 days in the primary outcome of cardiovascular death, myocardial infarction, cardiogenic shock, or heart failure. However, the results showed improvements in the surrogate outcomes of ST segment resolution and distal embolisation, but whether or not this finding would translate into a longer term benefit remained unclear. In this longer-term follow-up of the TOTAL study, we report the results on the primary outcome (cardiovascular death, myocardial infarction, cardiogenic shock, or heart failure) and secondary outcomes at 1 year. Analyses of the primary outcome were by modified intention to treat and only included patients who underwent index PCI. This trial is registered with ClinicalTrials.gov, number NCT01149044.
Between Aug 5, 2010, and July 25, 2014, 10 732 eligible patients were enrolled and randomly assigned to thrombectomy followed by PCI (n=5372) or to PCI alone (n=5360). After exclusions of patients who did not undergo PCI in each group (337 in the PCI and thrombectomy group and 331 in the PCI alone group), the final study population comprised 10 064 patients (5035 thrombectomy and 5029 PCI alone). The primary outcome at 1 year occurred in 395 (8%) of 5035 patients in the thrombectomy group compared with 394 (8%) of 5029 in the PCI alone group (hazard ratio [HR] 1·00 [95% CI 0·87–1·15], p=0·99). Cardiovascular death within 1 year occurred in 179 (4%) of the thrombectomy group and in 192 (4%) of 5029 in the PCI alone group (HR 0·93 [95% CI 0·76–1·14], p=0·48). The key safety outcome, stroke within 1 year, occurred in 60 patients (1·2%) in the thrombectomy group compared with 36 (0·7%) in the PCI alone group (HR 1·66 [95% CI 1·10–2·51], p=0·015).
Routine thrombus aspiration during PCI for STEMI did not reduce longer-term clinical outcomes and might be associated with an increase in stroke. As a result, thrombus aspiration can no longer be recommended as a routine strategy in STEMI.
Canadian Institutes of Health Research, Canadian Network and Centre for Trials Internationally, and Medtronic Inc.
Journal Article
25 years of neuroimaging in amyotrophic lateral sclerosis
by
Foerster, Bradley R.
,
Welsh, Robert C.
,
Feldman, Eva L.
in
631/378/1689/1285
,
692/700/1421/65
,
Amyotrophic lateral sclerosis
2013
The pathophysiological processes underlying onset and progression of amyotrophic lateral sclerosis (ALS) remain poorly understood. Unlike conventional imaging techniques, which provide information only at a gross structural level, advanced imaging modalities have shed light on the microstructural changes that accompany this disease. Eva Feldman and colleagues describe how advanced neuroimaging studies have delineated key factors, such as white matter tract integrity and brain metabolism, that are altered in ALS, and consider how such insights could aid diagnosis and treatment.
Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disease for which a precise cause has not yet been identified. Standard CT or MRI evaluation does not demonstrate gross structural nervous system changes in ALS, so conventional neuroimaging techniques have provided little insight into the pathophysiology of this disease. Advanced neuroimaging techniques—such as structural MRI, diffusion tensor imaging and proton magnetic resonance spectroscopy—allow evaluation of alterations of the nervous system in ALS. These alterations include focal loss of grey and white matter and reductions in white matter tract integrity, as well as changes in neural networks and in the chemistry, metabolism and receptor distribution in the brain. Given their potential for investigation of both brain structure and function, advanced neuroimaging methods offer important opportunities to improve diagnosis, guide prognosis, and direct future treatment strategies in ALS. In this article, we review the contributions made by various advanced neuroimaging techniques to our understanding of the impact of ALS on different brain regions, and the potential role of such measures in biomarker development.
Key Points
Advanced neuroimaging techniques noninvasively evaluate brain structure, chemistry, neural network connections, metabolism, and receptor distribution in neurodegenerative diseases
Nervous system changes in amyotrophic lateral sclerosis (ALS) involve the motor cortex, corticospinal tract, corpus callosum, frontal lobes, basal ganglia, thalamus, brainstem and cervical spinal cord
Neuroimaging in ALS provides evidence of neuronal loss, white matter tract disruption, alterations in neural networks, γ-aminobutyric acid system dysfunction, and changes in brain metabolism
Advanced neuroimaging techniques provide unique opportunities to more fully characterize and classify the different motor neuron disease subtypes
ALS is a heterogeneous disease, and neuroimaging studies generally include small numbers of patients with long disease duration, which could limit the generalizability of results
MRI and PET show promise for development of ALS biomarkers, although additional research is required to translate these technologies for clinical application
Journal Article
Altered resting-state amygdala functional connectivity in men with posttraumatic stress disorder
by
Wang, Xin
,
King, Anthony P.
,
Welsh, Robert C.
in
Adult
,
Adult and adolescent clinical studies
,
Amygdala (Brain)
2012
Converging neuroimaging research suggests altered emotion neurocircuitry in individuals with posttraumatic stress disorder (PTSD). Emotion activation studies in these individuals have shown hyperactivation in emotion-related regions, including the amygdala and insula, and hypoactivation in emotion-regulation regions, including the medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC). However, few studies have examined patterns of connectivity at rest in individuals with PTSD, a potentially powerful method for illuminating brain network structure.
Using the amygdala as a seed region, we measured resting-state brain connectivity using 3T functional magnetic resonance imaging in returning male veterans with PTSD and combat controls without PTSD.
Fifteen veterans with PTSD and 14 combat controls enrolled in our study. Compared with controls, veterans with PTSD showed greater positive connectivity between the amygdala and insula, reduced positive connectivity between the amygdala and hippocampus, and reduced anticorrelation between the amygdala and dorsal ACC and rostral ACC.
Only male veterans with combat exposure were tested, thus our findings cannot be generalized to women or to individuals with non–combat related PTSD.
These results demonstrate that studies of functional connectivity during resting state can discern aberrant patterns of coupling within emotion circuits and suggest a possible brain basis for emotion-processing and emotion-regulation deficits in individuals with PTSD.
Journal Article
Longitudinal surface‐based spatial Bayesian GLM reveals complex trajectories of motor neurodegeneration in ALS
by
Jelsone-Swain, Laura
,
Kalra, Sanjay
,
Mejia, Amanda F.
in
Aging
,
Amyotrophic lateral sclerosis
,
Amyotrophic Lateral Sclerosis - diagnostic imaging
2022
•We analyze a rich longitudinal fMRI dataset of 190 scans from ALS and HC subjects•We apply a novel longitudinal spatial Bayesian GLM in native cortical surface space•This approach has high accuracy and power compared with massive univariate approach•We find an inverted U-shaped activation trajectory, depending on ALS progression rate•Initial hyperactivation likely due to loss of inhibition, not functional compensation
Longitudinal fMRI studies hold great promise for the study of neurodegenerative diseases, development and aging, but realizing their full potential depends on extracting accurate fMRI-based measures of brain function and organization in individual subjects over time. This is especially true for studies of rare, heterogeneous and/or rapidly progressing neurodegenerative diseases. These often involve small samples with heterogeneous functional features, making traditional group-difference analyses of limited utility. One such disease is amyotrophic lateral sclerosis (ALS), a severe disease resulting in extreme loss of motor function and eventual death. Here, we use an advanced individualized task fMRI analysis approach to analyze a rich longitudinal dataset containing 190 hand clench fMRI scans from 16 ALS patients (78 scans) and 22 age-matched healthy controls (112 scans). Specifically, we adopt our cortical surface-based spatial Bayesian general linear model (GLM), which has high power and precision to detect activations in individual subjects, and propose a novel longitudinal extension to leverage information shared across visits. We perform all analyses in native surface space to preserve individual anatomical and functional features. Using mixed-effects models to subsequently study the relationship between size of activation and ALS disease progression, we observe for the first time an inverted U-shaped trajectory of motor activations: at relatively mild motor disability we observe enlarging activations, while at higher levels of motor disability we observe severely diminished activation, reflecting progression toward complete loss of motor function. We further observe distinct trajectories depending on clinical progression rate, with faster progressors exhibiting more extreme changes at an earlier stage of disability. These differential trajectories suggest that initial hyper-activation is likely attributable to loss of inhibitory neurons, rather than functional compensation as earlier assumed. These findings substantially advance scientific understanding of the ALS disease process. This study also provides the first real-world example of how surface-based spatial Bayesian analysis of task fMRI can further scientific understanding of neurodegenerative disease and other phenomena. The surface-based spatial Bayesian GLM is implemented in the BayesfMRI R package
Journal Article
Trial design: Rivaroxaban for the prevention of major cardiovascular events after transcatheter aortic valve replacement: Rationale and design of the GALILEO study
by
van Es, Gerrit-Anne
,
Windecker, Stephan
,
Thomitzek, Karen
in
Acute coronary syndromes
,
Aortic Valve Stenosis - surgery
,
Aspirin - therapeutic use
2017
Optimal antithrombotic treatment after transcatheter aortic valve replacement (TAVR) is unknown and determined empirically. The direct factor Xa inhibitor rivaroxaban may potentially reduce TAVR-related thrombotic complications and premature valve failure.
GALILEO is an international, randomized, open-label, event-driven, phase III trial in more than 1,520 patients without an indication for oral anticoagulation who underwent a successful TAVR (ClinicalTrials.govNCT02556203). Patients are randomized (1:1 ratio), 1 to 7days after a successful TAVR, to either a rivaroxaban-based strategy or an antiplatelet-based strategy. In the experimental arm, subjects receive rivaroxaban (10mg once daily [OD]) plus acetylsalicylic acid (ASA, 75-100mg OD) for 90days followed by rivaroxaban alone. In the control arm, subjects receive clopidogrel (75mg OD) plus ASA (as above) for 90days followed by ASA alone. In case new-onset atrial fibrillation occurs after randomization, full oral anticoagulation will be implemented with maintenance of the original treatment assignment. The primary efficacy end point is the composite of all-cause death, stroke, myocardial infarction, symptomatic valve thrombosis, pulmonary embolism, deep venous thrombosis, and systemic embolism. The primary safety end point is the composite of life-threatening, disabling, and major bleeding, according to the Valve Academic Research Consortium definitions.
GALILEO will test the hypothesis that a rivaroxaban-based antithrombotic strategy reduces the risk of thromboembolic complications post-TAVR with an acceptable risk of bleeding compared with the currently recommended antiplatelet therapy–based strategy in subjects without need of chronic oral anticoagulation.
Journal Article