Phd in ANGIO-CARDIO-THORACIC PATHOPHYSIOLOGY AND IMAGING

Thesis title: Infarto miocardico acuto nei giovani: caratterizzazione eziopatologica ed implicazioni diagnostico-terapeutiche

Acute Myocardial Infarction in Young Individuals: etiopathological characterization and diagnostic-therapeutic implications Aim: Acute myocardial infarction (AMI) remain a major cause of adverse outcomes in young individuals. This group is not well studied and has a unique risk profile with less traditional cardiovascular risk factors than older populations. Plaque rupture/erosion still remains the most common etiology of myocardial infarction, but unique syndromes such as epicardial or microvascular spasm related or unrelated to drug use, spontaneous coronary dissection, are more prevalent in this age group, as the diagnosis of myocardial infarction with non-obstructive coronary arteries (MINOCA) is more prevalent. This diversity of diagnoses and presentation, with the therapeutic implications, underscore the need to study the profile of myocardial infarction in young people. Methods: A total of 1296 patients with AMI were enrolled in the three-year period 2020-2022. They were divided into two groups: <50 years, >50 years. We evaluated the clinical, angiographic features, the different etiopathological mechanisms and the diagnostic and therapeutic implications. Results: Patients under 50 have a lower prevalence of arterial hypertension (29%) and diabetes mellitus (12%), while they are more often smokers (44%). Most are overweight as are patients over 50. STEMI is the most frequent clinical presentation, and single vessel occlusion is most common. 25% of patients recognized a non-atherosclerotic or undiagnosable cause on standard angiography, with 17% of MINOCA. The following causes have been identified with the help of intravascular imaging (optical coherence tomography OCT/intravascular ultrasound IVUS), ventriculography, cardiac MRI: spontaneous coronary dissection (3%), coronary arteries anomalies (4%), coronary thromboembolism (1%), takotsubo syndrome (2%), coronary spasm (3%), myocarditis (3%), type II AMI (3%). Conclusions: Patients under 50 with AMI have a unique risk profile, clinical and etiopathological characteristics. They have a higher prevalence of modifiable typical and atypical risk factors; these data underscore the importance of earlier interventions on lifestyle approaches, like smoking cessation, correct nutrition and aerobic physical activity. STEMIs are more prevalent in which the time variable is essential for improving the short- and long-term prognosis. The routine use, on the basis of clinical suspicion, of intravascular imaging, ventriculography, provocative tests and cardiac MRI allows to define the underlying cause and allows to establish a targeted and individualized therapy with improvement of the prognosis.