Clinical profile and prognosis of MINOCA and its mimickers
M Basile, M Moretti, P Stradaioli, L Toni, T Manaresi, A Maida, N Vasumini, M Di Leo, D Cavallo, L Bergamaschi, M Armillotta, F Angeli, D Fedele, C PizziAbstract
Background
Myocardial infarction with non-obstructive coronary arteries (MINOCA) accounts for 6–10% of acute myocardial infarction (AMI) cases and presents similarly to classic AMI, yet involves diverse pathophysiological mechanisms with distinct management and prognosis. Conditions mimicking MINOCA, such as myocarditis, Takotsubo syndrome (TTS), and non-ischemic cardiomyopathies (CMP), share overlapping features, complicating diagnosis. This study aims to define the clinical features, presentation, and outcomes of these conditions, with a focus on cardiac magnetic resonance (CMR) findings, to enhance therapeutic decision-making and patient care.
Methods
This study represents a predefined sub-analysis of the multicentre prospective registry AMIPE. We included consecutive patients admitted between January 2019 and August 2024 with a working diagnosis of AMI and non-obstructive coronary arteries (<50% stenosis). Patients were categorized as true MINOCA or MINOCA mimickers (myocarditis, TTS, or CMP) based on clinical evaluation and CMR findings. Clinical characteristics, in-hospital events, discharge therapies, and long-term outcomes—including all-cause mortality and major adverse cardiovascular events (MACE)—were analysed.
Results
A totality of 461 patients was enrolled: 218 MINOCA, 126 myocarditis, 97 TTS, and 20 CMP. Myocarditis patients were younger and predominantly male, whereas TTS patients were older and mostly female. TTS and CMP were associated with higher in-hospital mortality and greater long-term event rates. Over a median follow-up of 35 months, MACE occurred in 17.4% of patients, being most frequent in CMP (45%) and TTS (26%). Independent predictors of MACE included age (HR 1.05 per year), smoking (HR 1.95), and CMP diagnosis (HR 4.60).
Conclusions
Patients with acute coronary syndrome (ACS)-like presentations and non-obstructive coronary arteries exhibit heterogeneous clinical and prognostic profiles. While true MINOCA and myocarditis are generally associated with favourable outcomes, TTS and, especially, CMP carry significantly higher long-term mortality and MACE rates. Accurate phenotyping through integrated clinical, imaging, and laboratory evaluation is essential for diagnosis, risk stratification, and optimized management.Distribution of cardiovascular risk factors.