Clinical Profile and Lesions in Young Patients with Myocardial Infarction
Young patients with myocardial infarction (MI) present with distinct risk factor profiles, clinical presentations, and coronary lesion characteristics compared to older patients, with smoking being the predominant modifiable risk factor in this population. 1, 2
Clinical Presentation
- Young patients (≤55 years) with MI are equally likely to present with chest pain as older patients, with chest pain remaining the predominant symptom (87-89.5% of young patients) 3
- Young patients, particularly women, more frequently report associated symptoms compared to older patients, including:
- Epigastric symptoms
- Palpitations
- Pain or discomfort in the jaw, neck, arms, or between shoulder blades
- 61.9% of young women vs. 54.8% of young men report these associated symptoms 3
- Young patients are more likely to be diagnosed with ST-segment elevation myocardial infarction (STEMI) compared to older patients (62.0% vs. 50.0%) 1
Demographic Characteristics
- Young MI patients are predominantly male (86.3% vs. 65.8% in older patients) 1
- Young patients typically have higher body weight compared to older patients (mean 85.9 kg vs. 79.7 kg) 1
- The relative number of MI cases in young patients is increasing (from 1.20% in 2014 to 1.43% in 2017) 1
Risk Factor Profile
- Traditional cardiovascular risk factors are generally less prevalent in young MI patients compared to older patients, with notable exceptions 2, 4
- Smoking is the most significant modifiable risk factor in young MI patients:
- Family history of premature coronary artery disease (CAD) is common (44.3% of young MI patients) 5
- Dyslipidemia affects 39.35% of young MI patients, often presenting as familial combined hyperlipidemia with elevated lipoprotein-a levels 2, 5
- Hypertension is present in 37.7% of young MI patients 5
- Obesity affects 11.5% of young MI patients 5
- Diabetes mellitus is less common in young MI patients (8.2%) compared to older populations 5
- Sedentary lifestyle is highly prevalent among young MI patients 5
- Substance use may play a significant role:
- Cannabis, cocaine, and androgenic anabolic steroids are more commonly associated with MI in younger patients 2
Coronary Lesion Characteristics
- Young MI patients more frequently have the left anterior descending artery (LAD) as the infarct-related artery (51.3% vs. 36.3% in older patients) 1
- Non-significant coronary stenosis is more common in young MI patients (14.4% vs. 6.8% in older patients) 1
- Young patients typically have fewer atherosclerotic lesions but more eccentric plaques with inflammatory features 2
- Unique pathophysiological mechanisms more common in young patients include:
- Plaque erosion rather than plaque rupture
- Coronary microvascular dysfunction
- Spontaneous coronary artery dissection
- Coronary vasospasm related to drug use 4
Diagnostic and Treatment Considerations
- Young MI patients should be evaluated for both traditional and non-traditional risk factors, with particular attention to smoking status, family history, and substance use 2, 4
- Bioresorbable vascular scaffolds are more commonly used in young MI patients compared to older patients (5.6% vs. 0.9%) 1
- Genetic testing may be beneficial as genomic differences in coagulation and lipid metabolism pathways have been identified between young and older MI patients 2
- Risk assessment tools should be carefully applied, as they may underestimate risk in young patients, particularly women 3
Prevention Strategies
- Aggressive smoking cessation interventions are crucial for primary and secondary prevention in young adults 1, 5
- Screening for familial hyperlipidemia should be considered in young adults with family history of premature CAD 2
- Lifestyle modifications addressing sedentary behavior, obesity, and substance use are particularly important in this population 2, 5
- Early identification of young individuals at increased risk can guide targeted primary prevention strategies 2