Combining Angiography and Pre-specified Intracoronary Testing in Patients with Chronic Coronary Syndromes: the AID-ANGIO Study

Published in Congress: EUROPCR 2024

Dr. Ahmet Anıl Başkurt

Introduction
The role of invasive coronary angiography in chronic coronary syndrome has long been questioned. In coronary angiography, which is still the most commonly used diagnostic tool, visual assessment alone is not sufficient to determine the underlying cause of ischaemia, especially in the presence of non-obstructive coronary arteries. It is controversial to what extent the use of advanced invasive diagnostic methods will change the accuracy of the physician in detecting the underlying pathology.

Objective:
AID-ANGIO is an observational, prospective, single-cohort, multicentre study aimed at evaluating the diagnostic accuracy of a hierarchical strategy to identify obstructive and non-obstructive causes of myocardial ischaemia during coronary angiography in patients with chronic coronary syndrome. The primary endpoint will investigate the additional diagnostic value of this strategy compared to visual angiography alone in identifying mechanisms of ischaemia.

Method:
337 patients were included in the study. Patients underwent advanced invasive approach after a cardiologist made a temporary diagnosis and treatment plan based on angiography results. Then the ischaemia team made a definitive diagnosis and an updated plan. The first step in the hierarchy involves invasive coronary angiography to diagnose stenoses ≥90% by visual estimation. For stenoses <90% on angiography, physiological tests with FFR or RFR are used. If FFR/RFR is negative, patients undergo vascular function tests for coronary microvascular evaluation and acetylcholine testing to assess endothelium-dependent/independent impairment.

Results:
With angiography alone, the cause of ischaemia was found to be obstructive coronary arteries in 32.2% of patients, while no cause was found in 67.8%. With advanced invasive evaluation, the cause was identified in 84.2%:39.1% had obstructive coronary arteries, 45.1% had INOCA and 15.8% had no abnormality. Thus, the advanced invasive diagnostic method increased the diagnostic yield 2.6-fold (p < 0.001), and for 59.9% of patients the results changed the cardiologist's initial treatment plan. Two patients developed dissection and one patient developed ventricular fibrillation while performing the advanced invasive method. Ultimately, the test was found to be safe. The advanced invasive diagnostic method was performed in the catheterisation laboratory with an average additional 15 minutes in procedure time.

Conclusion:
The AID-ANGIO study demonstrated that performing advanced invasive diagnostic procedures, a hierarchical strategy compared to coronary angiography alone, to identify mechanisms of ischaemia in patients with chronic coronary syndrome improves diagnostic accuracy and changes the therapeutic approach.

Comment:
When coronary angiography does not show more than 90% stenosis, the use of additional diagnostic methods such as FFR/IFR and acetylcholine test increases the accuracy in determining the cause of ischaemia in the patient. Therefore, it has become important to have these drugs and tests ready in our cath labs.