Cost-effectiveness of adding a non-invasive acoustic rule-out test in the evaluation of patients with symptoms suggestive of coronary artery disease: rationale and design of the prospective, randomised, controlled, parallel-group multicenter FILTER-SCAD trial.

INTRODUCTION: Most patients with symptoms suggestive of chronic coronary syndrome (CCS) have no obstructive coronary artery disease (CAD) and better selection of patients to be referred for diagnostic tests is needed. The CAD-score is a non-invasive acoustic measure that, when added to pretest probability of CAD, has shown good rule-out capabilities. We aimed to test whether implementation of CAD-score in clinical practice reduces the use of diagnostic tests without increasing major adverse cardiac events (MACE) rates in patients with suspected CCS. METHODS AND ANALYSIS: FILTER-SCAD is a randomised, controlled, multicenter trial aiming to include 2000 subjects aged ≥30 years without known CAD referred for outpatient assessment for symptoms suggestive of CCS. Subjects are randomised 1:1 to either the control group: standard diagnostic examination (SDE) according to the current guidelines, or the intervention group: SDE plus a CAD-score. The subjects are followed for 12 months for the primary endpoint of cumulative number of diagnostic tests and a safety endpoint (MACE). Angina symptoms, quality of life and risk factor modification will be assessed with questionnaires at baseline, 3 months and 12 months after randomisation. The study is powered to detect superiority in terms of a reduction of ≥15% in the primary endpoint between the two groups with a power of 80%, and non-inferiority on the secondary endpoint with a power of 90%. The significance level is 0.05. The non-inferiority margin is set to 1.5%. Randomisation began on October 2019. Follow-up is planned to be completed by December 2022. ETHICS AND DISSEMINATION: This study has been approved by the Danish Medical Agency (2019024326), Danish National Committee on Health Research Ethics (H-19012579) and Swedish Ethical Review Authority (Dnr 2019-04252). All patients participating in the study will sign an informed consent. All study results will be attempted to be published as soon as possible. TRIAL REGISTRATION NUMBER: NCT04121949; Pre-results.

Use of diagnostic coronary angiography in women and men presenting with acute myocardial infarction: a matched cohort study.

BACKGROUND: Based on evident sex-related differences in the invasive management of patients presenting with acute myocardial infarction (AMI), we sought to identify predictors of diagnostic coronary angiography (DCA) and to investigate reasons for opting out an invasive strategy in women and men. METHODS: The study was designed as a matched cohort study. We randomly selected 250 female cases from a source population of 4000 patients hospitalized with a first AMI in a geographically confined region of Denmark from January 2010 to November 2011. Each case was matched to a male control on age and availability of cardiac invasive facilities at the index hospital. We systematically reviewed medical records for risk factors, comorbid conditions, clinical presentation, and receipt of DCA. Clinical justifications, as stated by the treating physician, were noted for the subset of patients who did not receive a DCA. RESULTS: Overall, 187 women and 198 men received DCA within 60 days (75 % vs. 79 %, hazard ratio: 0.82 [0.67-1.00], p = 0.047).In the subset of patients who did not receive a DCA (n = 114), clinical justifications for opting out an invasive strategy was not documented for 21 patients (18.4 %). Type 2 myocardial infarction was noted in 11 patients (women versus men; 14.5 % vs. 3.8 %, p = 0.06) and identified as a potential confounder of the sex-DCA relationship. Receipt of DCA was predicted by traditional risk factors for ischaemic heart disease (family history of cardiovascular disease, hypercholesterolemia, and smoking) and clinical presentation (chest pain, ST-segment elevations). Although prevalent in both women and men, the presence of relative contraindications did not prohibit the use of DCA. CONCLUSION: In this matched cohort of patients with a first AMI, women and men had different clinical presentations despite similar age. However, no differences in the distribution of relative contraindications for DCA were found between the sexes. Type 2 MI posed a potentiel confounder for the sex-related differences in the use of DCA. Importantly,clinical justification for opting out an invasive strategy was not documented in almost one fifth of patients not receiving a DCA.