Publications by authors named "Ramanathan Krishnan"

Article Synopsis
  • The introduction of high-sensitivity troponin (hsTnT) testing for emergency department patients with cardiac chest pain resulted in a significant reduction in length of stay, decreasing from approximately 464 minutes to 285 minutes.
  • The study included over 5,500 patients with cardiac chest pain, revealing a very low rate of missed major adverse cardiac events (MACE) at just 0.2%, indicating the safety of the new testing method.
  • No changes were observed in admission rates for both cardiac (around 24%) and noncardiac chest pain patients, while noncardiac cases remained stable in length of stay as well, underscoring the specific impact of hsTnT testing on cardiac chest pain
View Article and Find Full Text PDF

Background: The coronavirus disease 2019 (COVID-19) pandemic was characterized by rapid evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, affecting viral transmissibility, virulence, and response to vaccines/therapeutics. EMPATHY (NCT04828161), a phase 2 study, investigated the safety/efficacy of ensovibep, a multispecific designed ankyrin repeat protein (DARPin) with multivariant in vitro activity, in ambulatory patients with mild to moderate COVID-19.

Methods: Nonhospitalized, symptomatic patients (N = 407) with COVID-19 were randomized to receive single-dose intravenous ensovibep (75, 225, or 600 mg) or placebo and followed until day 91.

View Article and Find Full Text PDF
Article Synopsis
  • A significant number of atrial fibrillation (AF) cases remain unexplained by known acquired risk factors, leading researchers to explore genetic testing in a young AF population.
  • The study involved whole exome sequencing of 200 patients diagnosed with early-onset AF (under 60 years old), filtering genetic variants and classifying them according to established guidelines.
  • Results showed a low diagnostic yield (3.0%) for identifying likely pathogenic variants, indicating the need for more research to uncover additional genetic and environmental factors contributing to AF in patients without clear genetic links.
View Article and Find Full Text PDF

Introduction: Several studies have described prognostic value of serum neurofilament light chain (sNfL) at the group level in relapsing multiple sclerosis (RMS) patients. Here, we aimed to explore the temporal association between sNfL and development of subclinical disease activity as assessed by magnetic resonance imaging (MRI) at the group level and evaluate the potential of sNfL as a biomarker for capturing subclinical disease activity in individual RMS patients.

Methods: In the 12-week APLIOS study, patients (N = 284) received subcutaneous ofatumumab 20 mg.

View Article and Find Full Text PDF

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with potential resistance to existing drugs emphasizes the need for new therapeutic modalities with broad variant activity. Here we show that ensovibep, a trispecific DARPin (designed ankyrin repeat protein) clinical candidate, can engage the three units of the spike protein trimer of SARS-CoV-2 and inhibit ACE2 binding with high potency, as revealed by cryo-electron microscopy analysis. The cooperative binding together with the complementarity of the three DARPin modules enable ensovibep to inhibit frequent SARS-CoV-2 variants, including Omicron sublineages BA.

View Article and Find Full Text PDF

South Asians (SAs) experience a higher prevalence and earlier onset of coronary artery disease and have worse outcomes compared with White Caucasians (WCs) following invasive revascularisation procedures, a mainstay of coronary artery disease (CAD) management. We sought to review the differences in the CAD pattern and risk factors between SA and WC patients and to discuss their potential impact on the development of coronary disease, acute coronary syndrome, and revascularisation outcomes. SAs have a more diffuse pattern with multivessel involvement compared with WCs.

View Article and Find Full Text PDF

Objective: This study aims to confirm the prognostic value of baseline serum neurofilament light chain (sNfL) for on-study disease activity and worsening in patients with relapsing MS (RMS).

Background: Previous studies suggested that sNfL could be a prognostic biomarker in RMS. In the phase 3 ASCLEPIOS I/II trials in which ofatumumab demonstrated better efficacy outcomes than teriflunomide, treatment with ofatumumab also led to significantly reduced sNfL levels compared to teriflunomide treatment.

View Article and Find Full Text PDF

Background: In the phase III ASCLEPIOS I and II trials, participants with relapsing multiple sclerosis receiving ofatumumab had significantly better clinical and magnetic resonance imaging (MRI) outcomes than those receiving teriflunomide.

Objectives: To assess the efficacy and safety of ofatumumab versus teriflunomide in recently diagnosed, treatment-naive (RDTN) participants from ASCLEPIOS.

Methods: Participants were randomized to receive ofatumumab (20 mg subcutaneously every 4 weeks) or teriflunomide (14 mg orally once daily) for up to 30 months.

View Article and Find Full Text PDF
Article Synopsis
  • Ofatumumab is an anti-CD20 monoclonal antibody approved for treating relapsing multiple sclerosis (RMS) that interacts with specific B cells, allowing for effective subcutaneous treatment at lower doses.
  • The study aimed to analyze how ofatumumab concentration relates to B cell levels while considering variables like body weight and age, using advanced modeling techniques on data from numerous patients.
  • Ultimately, the research confirmed that the 20-mg dose of ofatumumab effectively maintains desired B cell levels without needing adjustments based on individual patient characteristics.
View Article and Find Full Text PDF

Knowledge of the impacts of the anti-CD20 monoclonal antibody ofatumumab on the developing immune system is limited. This study examined the effects of intravenous ofatumumab on pregnancy, parturition, and lactation, and on pre- and postnatal survival and development in cynomolgus monkeys, an established model for developmental toxicity assessment. Pregnant cynomolgus monkeys (n = 42) were randomized to receive vehicle only (control group; n = 14), low-dose ofatumumab (n = 14), or high-dose ofatumumab (n = 14).

View Article and Find Full Text PDF

Background: Ofatumumab, the first fully human anti-CD20 monoclonal antibody, has been developed as a treatment for relapsing multiple sclerosis (RMS) which can be self-administered at home.

Objective: To investigate the efficacy and safety of ofatumumab in RMS patients from Japan and Russia.

Methods: APOLITOS included a 24-week, double-blind, placebo-controlled core-part followed by an open-label extension-part.

View Article and Find Full Text PDF

Background: Obesity is a potential risk factor for development of type 2 diabetes mellitus (T2DM). To achieve long-term weight reduction in patients with T2DM and obesity using comprehensive lifestyle management program (LMP).

Materials And Methods: This 48-week interventional, multicenter, parallel-group, open-label study included patients aged ≥18 years with T2DM and a body mass index (BMI) of 27-40 kg/m.

View Article and Find Full Text PDF
Article Synopsis
  • * A young, healthy man developed acute perimyocarditis, presenting with chest pain and heart failure symptoms three days after receiving his second dose of the vaccine.
  • * His symptoms resolved within nine days, emphasizing the need for healthcare providers to recognize and manage this uncommon but serious side effect of mRNA vaccines.
View Article and Find Full Text PDF

It is now widely recognized that COVID-19 illness can be associated with significant intermediate and potentially longer-term physical limitations. The term, "long COVID-19" is used to define any patient with persistent symptoms after acute COVID-19 infection (ie, after 4 weeks). It is postulated that cardiac injury might be linked to symptoms that persist after resolution of acute infection, as part of this syndrome.

View Article and Find Full Text PDF

Background: Ofatumumab, a subcutaneous anti-CD20 monoclonal antibody, selectively depletes B cells. Teriflunomide, an oral inhibitor of pyrimidine synthesis, reduces T-cell and B-cell activation. The relative effects of these two drugs in patients with multiple sclerosis are not known.

View Article and Find Full Text PDF
Article Synopsis
  • - The FREEDOM trial found that coronary artery bypass grafting (CABG) is more effective than percutaneous coronary intervention (PCI) for patients with diabetes and multivessel coronary artery disease.
  • - A study in British Columbia evaluated changes in treatment practices and identified barriers and facilitators for implementing FREEDOM trial findings from 2007-2014, revealing a significant decline in PCI:CABG ratios after the trial's publication.
  • - Despite an increased proportion of CABG procedures post-FREEDOM trial, variations in practice across cardiac centers were linked to barriers related to evidence applicability, healthcare provider knowledge, patient preferences, and systemic issues.
View Article and Find Full Text PDF

Background: Contemporary guidelines recommend that atrial fibrillation (AF) be classified into paroxysmal and persistent AF based on clinical assessment, with these categorizations forming the basis of therapeutic recommendations. While pragmatic, clinical assessment may introduce misclassification errors, which may impact treatment decisions. We sought to determine the relationship between AF classification, baseline AF burden, and post-ablation arrhythmia outcomes.

View Article and Find Full Text PDF
Article Synopsis
  • Physicians assess stroke and bleeding risks in nonvalvular atrial fibrillation (AF) patients but the accuracy of their assessments compared to empirical data is questionable.
  • A study analyzed data from 1,035 physicians and over 10,000 patients, revealing that male physicians often misjudged stroke risks for female patients while female physicians misjudged risks for male patients.
  • Though there were some differences in risk assessment accuracy based on the sex of the physician and patient, over 90% of participants still received appropriate anticoagulation treatment.
View Article and Find Full Text PDF

Background: The FREEDOM (Future Revascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multivessel Disease) trial demonstrated that for patients with diabetes mellitus (DM) and multivessel coronary disease (MVD), coronary artery bypass grafting (CABG) is superior to percutaneous coronary intervention with drug-eluting stents (PCI-DES) in reducing the rate of major adverse cardiovascular and cerebrovascular events after a median follow-up of 3.8 years. It is not known, however, whether CABG confers a survival benefit after an extended follow-up period.

View Article and Find Full Text PDF

Background: Investigators have identified important racial identity/ethnicity-based differences in some aspects of acute coronary syndrome (ACS) care and outcomes (time to presentation, symptoms, receipt of coronary angiography/revascularization, repeat revascularization, mortality). Patient-based differences such as pathophysiology and treatment-seeking behavior account only partly for these outcome differences. We sought to investigate whether there are racial identity/ethnicity-based variations in the initial emergency department (ED) triage and care of patients with suspected ACS in Canadian hospitals.

View Article and Find Full Text PDF

Background: For patients with symptomatic, sustained atrial fibrillation (AF), a "pill-in-the-pocket" antiarrhythmic drug (PIP-AAD) strategy has been proposed to reduce emergency department (ED) use.

Objective: To assess the clinical utility of a protocolled PIP-AAD approach within contemporary practice.

Methods: Consecutive patients who hemodynamically tolerated symptomatic, sustained AF were prospectively managed with the PIP-AAD strategy.

View Article and Find Full Text PDF

Background: Randomized trial data support the superiority of coronary artery bypass grafting (CABG) surgery over percutaneous coronary intervention (PCI) in diabetic patients with multivessel coronary artery disease (MV-CAD). However, whether this benefit is seen in a real-world population among subjects with stable ischemic heart disease (SIHD) and acute coronary syndromes (ACS) is unknown.

Objectives: The main objective of this study was to assess the generalizability of the FREEDOM (Future REvascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multi-vessel Disease) trial in real-world practice among patients with diabetes mellitus and MV-CAD in residents of British Columbia, Canada.

View Article and Find Full Text PDF

Using data collected from 2 national atrial fibrillation (AF) primary care physician chart audits (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation [FREEDOM AF] and Co-ordinated National Network to Engage Physicians in the Care and Treatment of Patients With Atrial Fibrillation [CONNECT AF]), we evaluated the frequency of, and factors associated with, the use of cardiovascular (CV) evidence-based therapies in Canadian AF outpatients with at least 1 CV risk factor or co-morbidity. Of the 11,264 patients enrolled, 9,495 (84.3%) were eligible for one or more CV evidence-based therapies.

View Article and Find Full Text PDF

Background: Severe inotrope-dependent acute heart failure (AHF) is associated with poor clinical outcomes. There are currently no well-defined blood biomarkers of response to treatment that can guide management or identify recovery in this patient population. In the present study, we characterized the levels of novel and emerging circulating biomarkers of heart failure in patients with AHF over the first 30 days of medical management or mechanical circulatory support (MCS).

View Article and Find Full Text PDF