Study to Improve Cardiovascular Outcomes in high-risk older patieNts (ICON1) with acute coronary syndrome: study design and protocol of a prospective observational study

Vijay Kunadian, R Dermot G Neely, Hannah Sinclair, Jonathan A Batty, Murugapathy Veerasamy, Gary A Ford, Weiliang Qiu, Vijay Kunadian, R Dermot G Neely, Hannah Sinclair, Jonathan A Batty, Murugapathy Veerasamy, Gary A Ford, Weiliang Qiu

Abstract

Introduction: The ICON1 study (a study to Improve Cardiovascular Outcomes in high-risk older patieNts with acute coronary syndrome) is a prospective observational study of older patients (≥75 years old) with non-ST-elevation acute coronary syndrome managed by contemporary treatment (pharmacological and invasive). The aim of the study was to determine the predictors of poor cardiovascular outcomes in this age group and to generate a risk prediction tool.

Methods and analysis: Participants are recruited from 2 tertiary hospitals in the UK. Baseline evaluation includes frailty, comorbidity, cognition and quality-of-life measures, inflammatory status assessed by a biomarker panel, including microRNAs, senescence assessed by telomere length and telomerase activity, cardiovascular status assessed by arterial stiffness, endothelial function, carotid intima media thickness and left ventricular systolic and diastolic function, and coronary plaque assessed by virtual histology intravascular ultrasound and optical coherence tomography. The patients are followed-up at 30 days and at 1 year for primary outcome measures of death, myocardial infarction, stroke, unplanned revascularisation, bleeding and rehospitalisation.

Ethics and dissemination: The study has been approved by the regional ethics committee (REC 12/NE/016). Findings of the study will be presented in scientific sessions and will be published in peer-reviewed journals.

Trial registration number: NCT01933581: Pre-results.

Keywords: Study design; acute coronary syndrome; older patients.

Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Figures

Figure 1
Figure 1
ICON1 study flow chart. CCS, Canadian Cardiovascular Society; ICON1, Improve Cardiovascular Outcomes in high-risk older patieNts with acute coronary syndrome; MoCA, Montreal Cognitive Assessment; NSTEMI, non-ST-elevation acute coronary syndrome; NYHA, New York Heart Association; OCT, optical coherence tomography; PCI, percutaneous coronary intervention; UA, unstable angina; VH-IVUS, virtual histology—intravascular ultrasound.
Figure 2
Figure 2
Decision tree for lesion classification on VH-IVUS, virtual histology—intravascular ultrasound (VH-IVUS) with image examples. Adapted from García-García et al.
Figure 3
Figure 3
Study power. A plot of power versus hazard ratios for the sample size of 300 patients and 1-year mortality rates.

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