Intracoronary Provocative Test With Acetylcholine in Patients With Stable Myocardial Ischemia or Myocardial Infarction and Non-Obstructive Coronary Arteries: the Provoke Study
Coronary vasomotor disorders, occurring both at microvascular and epicardial level, have been demonstrated as responsible for myocardial ischemia in a sizeable group of patients undergoing coronary angiography (CAG), with clinical manifestations ranging from ischemia with non-obstructive coronary arteries (INOCA) to myocardial infarction with non-obstructive coronary arteries (MINOCA), along with life-threatening arrhythmias and sudden cardiac death. Intracoronary provocative testing with administration of acetylcholine (ACh) at the time of CAG may elicit epicardial coronary spasm or microvascular spasm in susceptible individuals, and therefore is assuming paramount importance for the diagnosis of functional coronary alterations in patients with suspected myocardial ischemia and non-obstructive coronary artery disease (CAD). However, previous studies mainly focused on patients with INOCA, whilst MINOCA patients were often underrepresented. Assessing the presence of coronary vasomotor disorders is of mainstay importance in order to implement the optimal management and improve clinical outcomes. Clinical predictors for a positive ACh test could allow the development of predictive models for a positive or negative response based on clinical and/or angiographic features readily available in the catheterization laboratories, thus helping clinicians in the diagnosis of coronary vasomotor disorders even in patients at high risk of complications.
• Age ≥18 years.
• INOCA or MINOCA as clinical presentation.
• Patient that underwent an intracoronary provocative test with ACh at the time of CAG, as suggested in current guidelines and consensus and according to clinical practice and medical choice and independently from the present study.
• Patients with INOCA will be defined as those with a stable pattern of typical chest pain on exertion, at rest or both, without any sign of acute myocardial infarction (MI), and/or evidence of inducible myocardial ischemia undergoing a scheduled hospital admission for CAG.
• Patients with MINOCA will be diagnosed based on clinical evidence of acute myocardial ischemia, detection of raise and fall of serum troponin T levels with at least one value exceeding the 99th percentile of a normal reference population and at least one of the following: 1) symptoms of myocardial ischemia (one or more episodes of chest pain at rest typical enough to suggest a cardiac ischemic origin in the previous 24 hours); 2) new ischemic ECG changes (ST-segment and/or T wave abnormalities); 3) development of pathological Q waves; 4) imaging evidence of new loss of viable myocardium or new regional wall motion abnormality in a pattern consistent with an ischemic aetiology (19).
• Written informed consent to participate.