Publications by authors named "Aun Y Chong"

Background: Canada is the only country with universal health care lacking universal pharmaceutical care (pharmacare). Currently, a minority portion of the population has drug coverage. Furthermore, there may be discordance between provincial plans of medications that are covered.

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Background: Disparities exist in medicine and can affect patient care. We sought to understand influences of racial biases in diagnostic testing within a Cardiac CT (CCT) population.

Methods: Race of CCT patients, referring physicians and the population in the catchment area were captured between February 2006 and November 2021.

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Background: Coronary microvascular dysfunction (CMD) has been implicated in the pathogenesis of Takotsubo syndrome (TTS). Positron emission tomography (PET) plays a key role in the assessment of CMD through myocardial flow reserve (MFR). However, there is limited information on the temporal progression of MFR and its relationship to coronary artery disease (CAD) in TTS patients.

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Background: Myocardial infarction with nonobstructive coronary artery disease (MINOCA) is defined as acute myocardial infarction (AMI) with angiographically nonobstructive coronary artery disease. MINOCA represents 6% of all AMI cases and is associated with increased mortality and morbidity. However, the wide array of pathophysiological factors and causes associated with MINOCA presents a diagnostic conundrum.

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Coronary artery bypass grafting (CABG) has evolved to become the criterion standard in elective revascularisation for coronary artery disease (CAD), particularly in patients with complex or multivessel CAD, left main involvement, diabetes mellitus, or left ventricular dysfunction. Despite the superiority of CABG in patients with the most advanced forms of CAD, a standard CABG operation, through a median sternotomy and with the use of cardiopulmonary bypass, carries well recognised challenges. In this article, we describe newer approaches, such as off-pump CABG, minimally invasive bypass grafting, robotic CABG, and hybrid coronary revascularisation, which we consider as necessary ways to minimise invasion, reduce recovery time, provide the benefits of arterial grafting to more patients, and offer alternatives to mitigate the adverse effects of conventional sternotomy and cardiopulmonary bypass.

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Background: Positron emission tomography (PET) has demonstrated utility for diagnostic and prognostic assessment of cardiac allograft vasculopathy (CAV) but has not been evaluated in the first year after transplant.

Objectives: The authors sought to evaluate CAV at 1 year by PET myocardial blood flow (MBF) quantification.

Methods: Adults at 2 institutions enrolled between January 2018 and March 2021 underwent prospective 3-month (baseline) and 12-month (follow-up) post-transplant PET, endomyocardial biopsy, and intravascular ultrasound examination.

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Background: Inflammation is a key mediator in the development and progression of the atherosclerotic disease process as well as its resultant complications, like myocardial infarction (MI), stroke and cardiovascular (CV) death, and is emerging as a novel treatment target. Trials involving anti-inflammatory medications have demonstrated outcome benefit in patients with known CV disease. In this regard, colchicine appears to hold great promise.

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Purpose Of Review: The goal of this article is to review the data supporting the use of fractional flow reserve derived from coronary computed tomography angiography (FFR) in patients with chest pain.

Review Findings: Numerous clinical trials have demonstrated that the diagnostic accuracy of coronary computed tomography angiography (CCTA) can be improved with the use of FFR, primarily due to its superior specificity when compared to CCTA alone. This promising development may help reduce the need for invasive angiography in patients presenting with chest pain.

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Background: Early cardiac allograft vasculopathy (CAV) prognostication is needed to improve long-term outcomes after heart transplantation. We characterized first year posttransplant coronary anatomic-physiologic alterations to determine predictors of early CAV progression.

Methods: Heart transplant recipients at 2 institutions (enrolled January 2018 to March 2021) underwent prospective evaluation 3 and 12-month posttransplant with angiography and left anterior descending artery intravascular ultrasound, optical coherence tomography, fractional flow reserve, coronary flow reserve, and index of microcirculatory resistance measurements.

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Article Synopsis
  • The study aimed to improve post-revascularization care for patients and document ongoing risk factors a year after treatment, using a web-based registry.
  • Conducted at the University of Ottawa Heart Institute, data from 4147 patients who underwent various revascularization procedures were analyzed to track complications like major adverse cardiovascular events (MACE) over a median follow-up of 13.3 months.
  • Results showed that 11% of patients had MACE within the follow-up period, with specific attention given to women and patients with multiple risk factors, highlighting the need for better management of ongoing health risks post-procedure.
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The optimal length of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) remains debated. Current guidelines recommend individualized treatment with consideration of risk scores. We sought to evaluate the degree of agreement in treatment recommendations and the ability to predict ischemic and bleeding complications of the PRECISE-DAPT (predicting bleeding complications in patients undergoing stent implantation and subsequent dual antiplatelet therapy) and DAPT scores.

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Background: De-escalation from potent platelet P2Y12 inhibitors to clopidogrel is common. Despite having a clinical rationale, non-bleeding-related de-escalation when a lateral change between potent agents is an option may put patients at increased ischemic risk. We set out to define the scope of P2Y12 inhibitor de-escalation in a large clinical registry and evaluate the potential impact of non-bleeding-related de-escalation on clinical outcomes.

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Importance: Comatose survivors of out-of-hospital cardiac arrest experience high rates of death and severe neurologic injury. Current guidelines recommend targeted temperature management at 32 °C to 36 °C for 24 hours. However, small studies suggest a potential benefit of targeting lower body temperatures.

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We identified the prevalence of elevated high-sensitivity C-reactive protein and interleukin-6 in patients with recent cardiovascular (CV) events with or without prediabetes/diabetes, and in a control group of patients with remote CV events. Interleukin-6 was elevated in patients with prediabetes/diabetes and recent CV events (median, 4.84 pg/mL; interquartile range, 3.

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Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is prescribed for 1-year after myocardial infarction. Two clinical strategies are considered at 1-year: continuation of DAPT or "Dual Pathway" (DP), using aspirin and rivaroxaban. No head-to-head comparative studies exist.

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Background The optimal antiplatelet strategy for patients with acute coronary syndromes who require coronary artery bypass surgery remains unclear. While a more potent antiplatelet regimen will predispose to perioperative bleeding, it is hypothesized that through "platelet quiescence," ischemic protection conferred by such therapy may provide a net clinical benefit. Methods and Results We compared patients undergoing coronary artery bypass surgery who were treated with a more potent antiplatelet inhibition strategy with those with a less potent inhibition through a meta-analysis.

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Background: Management of ST-elevated myocardial infarction (STEMI) necessitates rapid reperfusion. Delays prolong myocardial ischemia and increase the risk of complications, including death. The COVID-19 pandemic may have impacted STEMI management.

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Purpose: The impact of cardiology fellows (CFs) and interventional cardiology fellows (ICFs) on patient radiation and contrast exposure during diagnostic coronary angiography and percutaneous coronary intervention is unknown.

Methods: Between 2011 and 2014, 16,175 cases were retrospectively assessed involving 27 CFs, 22 ICFs and 24 staff as primary operators.

Results: During diagnostic coronary angiography, ICFs administered the lowest radiation dose (5,648±5,523 cGy*cm2; 1.

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Background: We previously demonstrated high diagnostic accuracy of Rubidium-82 positron emission tomography (PET) myocardial blood flow (MBF) quantification for CAV. The purpose of this study was to validate multiparametric PET detection of CAV by combined rate-pressure-product-corrected myocardial flow reserve (cMFR), stress MBF, and coronary vascular resistance (CVR) assessment.

Methods And Results: Diagnostic CAV cut-offs of cMFR < 2.

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Importance: Among patients with ST-segment elevation myocardial infarction (STEMI) referred for primary percutaneous coronary intervention (PCI), a survival benefit associated with radial access compared with femoral access remains controversial.

Objective: To assess whether there is a survival benefit when radial access is used instead of femoral access among patients with STEMI referred for primary PCI.

Design, Setting, And Participants: This multicenter, open-label, randomized clinical trial was conducted at 5 PCI centers in Canada.

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Background: Cardiac allograft vasculopathy (CAV) is a leading cause of graft failure and death after heart transplantation. Absolute myocardial blood flow (MBF) quantification using rubidium 82 (Rb-82) positron emission tomography (PET) could enable evaluation of diagnostically challenging diffuse epicardial and microvascular disease in CAV.

Objectives: The authors aimed to evaluate Rb-82 PET detection of CAV.

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