Diagnostic Performance of Exercise Stress Tests for the Detection of Epicardial and Microvascular Coronary Artery Disease

Diagnostic Performance of Exercise Stress Tests for the Detection of Epicardial and Microvascular Coronary Artery Disease

Prospective, single-arm, multicenter study of patients with an intermediate pre-test probability of CAD and positive exercise stress tests referred for invasive angiography. Patients underwent an invasive diagnostic procedure (IDP) with measurement of fractional flow reserve (FFR) and index of microvascular resistance (IMR) in at least one coronary vessel. The objective was to determine the false discovery rate (FDR) of cardiac exercise stress tests with both FFR and IMR as references.

The Redefining the Diagnostic Performance of Non-invasive Tests for the Detection of Coronary Artery Disease: UZ Clear is an investigator-initiated, single-arm, multicenter, prospective study of patients presenting with chest pain with an intermediate probability of CAD. The intermediate pre-test probability of CAD was defined based on the European Society of Cardiology Guidelines as a score between 15% and 85% based on age, sex, and the nature of symptoms. All patients had a positive exercise stress test and were referred for an invasive evaluation. Patients underwent a study protocol with an invasive diagnostic procedure (IDP) consisting of measurements of FFR and IMR in at least one coronary vessel. Exclusion criteria are acute coronary syndromes, known coronary artery disease, previous myocardial infarction, previous revascularization, and abnormal baseline electrocardiogram (ECG). All data were centrally collected and analyzed by the core laboratory.

The primary objective was to determine the false discovery rate of exercise stress tests using an interventional diagnostic procedure (IDP) with indexes of epicardial (FFR) and microvascular resistance (IMR) as clinical references. The secondary objective was to assess the impact of an IDP accounting for the presence of CMD on the accuracy of exercise stress tests.

Inclusion Criteria:

- 1. Stable angina-like chest pain (typical or atypical) with intermediate (15-85%) pre-test probability of coronary artery disease using the ESC criteria.

2. Positive non-invasive exercise test, or inconclusive stress with additional positive imaging.

Exclusion Criteria:

1. Age <30 or >80-year old
2. Acute coronary syndromes.
3. Known coronary artery disease
4. Inability to perform exercise tests.
5. Previous myocardial infarction.
6. Previous CABG/PCI
7. Left ventricular dysfunction EF <35% or NYHA class III-IV
8. Uncontrolled or recurrent ventricular tachycardia
9. Atrial fibrillation
10. Severe renal dysfunction, defined as an eGFR <30 ml/min/1.73m2
11. Contra-indication to adenosine (e.g. asthma bronchial, severe COPD)
12. Active cancer
13. Recent stroke
14. Cardiomyopathy (dilated, hypertrophic, amyloidosis, arrhythmogenic right ventricular dysplasia)
15. Left Bundle Branch Block or baseline ST-segment depression >1mm.
16. Congenital heart disease
17. More than moderate valve disease