This is a single-center, prospective interventional study evaluating noninvasive coronary function testing using transthoracic Doppler echocardiography of the left anterior descending coronary artery in patients with stable angina and nonobstructive coronary artery disease (ANOCA) who previously underwent invasive coronary function testing (adenosine and/or acetylcholine).
A group of age- and sex-matched healthy volunteers will be enrolled to support interpretation of potentially abnormal noninvasive responses observed in patients.
Age between 18 and 90 years;
ICA performed within the previous 12 months from enrollment and characterized by: (a) absence of obstructive CAD (<50% diameter reduction or FFR by >0.80); (b) invasive assessment of epicardial/microvascular spasm by acetylcholine test;
Signed informed consent.
Presentation as an acute coronary syndrome (i.e. unstable chest pain) or a typical history of variant angina (frequent angina pain at rest with ST-segment elevation at the ECG, caused by recurrent coronary spasm);
Previous coronary revascularization with surgical intervention;
Asthma or known intolerance or contraindications to dipyridamole;
Serious medical conditions, including renal failure (eGFR <30 mL/min), liver diseases, malignancies, and acute or chronic inflammatory diseases;