From the Guidelines
Management of Non-Obstructive Coronary Artery disease (NOCA) and Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA) involves a comprehensive approach. The primary goal is to identify the underlying cause of MINOCA, which can be categorized into four main groups: epicardial coronary artery disorders, imbalance between oxygen supply and demand, coronary endothelial dysfunction, and myocardial disorders without involvement of the coronary arteries 1.
Diagnostic Criteria
The diagnosis of MINOCA is made based on the following criteria:
- Detection of a rise or fall in cardiac troponin with at least one value above the 99th percentile upper reference limit
- Corroborative clinical evidence of infarction, such as symptoms of myocardial ischemia, new ischemic electrocardiographic changes, or imaging evidence of new loss of viable myocardium
- Non-obstructive coronary arteries on angiography, defined as the absence of obstructive disease on angiography (i.e., no coronary artery stenosis >50%) in any major epicardial vessel
- No specific alternate diagnosis for the clinical presentation 1
Management Strategies
The management of MINOCA involves a step-wise approach:
- Initial Assessment: Proper initial assessment of LV wall motion should be promptly performed in the acute setting using LV angiography or echocardiography
- Cardiac Magnetic Resonance (CMR): CMR is a key diagnostic tool in the differential diagnosis of Takotsubo syndrome, myocarditis, or true MI, and can identify the underlying cause in as many as 87% of patients with MINOCA
- Medical Therapy: Medical therapy based on coronary functional test results should be considered to improve symptoms and quality of life, including:
- ACE-I for symptom control in patients with endothelial dysfunction
- Beta-blockers for symptom control in patients with microvascular angina associated with reduced coronary/myocardial blood flow reserve
- Calcium channel blockers and nitrates for symptom control in patients with vasospastic angina
- Intracoronary Imaging: Intracoronary imaging with IVUS or OCT may be valuable for the detection of unrecognized causes at coronary angiography, especially when thrombus, plaque rupture or erosion, or SCAD are suspected
Treatment Considerations
Treatment should target the most probable causes of MINOCA, with negative provocative tests and CMR. The benefit of DAPT (aspirin + P2Y12 receptor inhibitor) should be considered based on pathophysiological considerations, although evidence is scarce 1.
In patients with ANOCA/INOCA, medical therapy based on coronary functional test results should be considered to improve symptoms and quality of life, including the use of nitrates, calcium channel blockers, and beta-blockers 1.
Overall, the management of NOCA and MINOCA requires a comprehensive and individualized approach, taking into account the underlying cause and pathophysiological mechanisms involved.
From the Research
Management of Non-Obstructive Coronary Artery Disease (NOCA) and Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA)
The management of MINOCA is complex and requires a comprehensive assessment to identify the underlying cause of the condition. Some key points to consider include:
- MINOCA is a heterogeneous group of conditions that include both atherosclerotic and non-atherosclerotic causes, resulting in myocardial damage that is not due to obstructive coronary artery disease 2.
- The cornerstone of managing MINOCA patients is to identify the underlying mechanism to achieve the target treatment 2.
- Intravascular imaging, such as intravascular ultrasound and optical coherence tomography, can help identify pathological alterations of the epicardial vessels that are not visible by coronary angiography 3.
- Cardiac magnetic resonance is the gold standard for detection of myocardial infarction in the setting of MINOCA 2, 4.
- The diagnostic pathway for MINOCA may involve multiple investigations, including coronary angiography, intravascular imaging, and cardiac magnetic resonance 3, 4.
- Therapeutic management of MINOCA is limited due to the lack of evidence-based literature and prospective randomized controlled studies, and the strategy is patient-specific 5.
Diagnostic Strategies
Some diagnostic strategies for MINOCA include:
- Coronary angiography to rule out obstructive coronary artery disease 6, 3.
- Intravascular imaging, such as intravascular ultrasound and optical coherence tomography, to identify pathological alterations of the epicardial vessels 3.
- Cardiac magnetic resonance to detect myocardial infarction and identify the underlying cause of MINOCA 2, 4.
- Optical coherence tomography (OCT) and intravenous ultrasound (IVUS) to stratify the underlying mechanism 5.
Treatment Options
Some treatment options for MINOCA include:
- Targeted therapies based on the underlying cause of the condition 6.
- Patient-specific management due to the lack of evidence-based literature and prospective randomized controlled studies 5.
- Consideration of the underlying etiology, such as coronary artery spasm, spontaneous coronary artery dissection, coronary thromboembolism, coronary plaque disruption, coronary microvascular dysfunction, and supply and demand mismatch 3, 2, 5.