Sex specific, women more often non-plaque related heart attack:
Overall MI incidence was nearly three times higher in men under 65 compared to women under 65, with 137 events per 100,000 person-years among men compared with 48 among women. For men, the “classic” cause of a heart attack—atherothrombotic MI—accounted for the majority of cases, representing roughly three-quarters of all MIs and occurring at a rate of 105 per 100,000 person-years.
But remarkably, this pattern was reversed in women. Though atherothrombosis still caused more MIs than any other individual mechanism, it accounted for less than half (47%) of the total number of cases in this young cohort. …
Some of the symptoms and differences based on gender:
While men typically experience symptoms that align with the traditional description of myocardial ischemia—such as central chest pressure, squeezing or heaviness, and pain radiating to the arm, jaw, or shoulder, often triggered or worsened by exertion—women, by contrast, often report symptoms such as shortness of breath, nausea, vomiting, unusual fatigue, lightheadedness, palpitations, or discomfort in the back, neck, or upper abdomen (though they frequently present with the symptoms seen in men, as well). …
MI affecting higher and more lateral areas might present with shoulder pain, whereas an MI affecting a lower part of the heart might present with abdominal pain or a sense of indigestion. When these types of symptoms occur suddenly and persist for more than a few minutes without any clear cause, they may signal a heart attack, and the policy across US emergency rooms is to triage them as such.
Good question, some traditional risk factors could be relevant:
…other mechanisms can occur even in the absence of other cardiovascular risk factors (though classic “heart healthy” measures like regular exercise, stress management, and avoidance of smoking can reduce risk).
But these MI’s are relatively rare now:
Even in a general population, these atherosclerosis-independent (i.e., excluding SSDM) mechanisms have been estimated to account for 5–10% of all MIs—a small but significant minority—and women are disproportionately at risk across all age groups
Being aware of the symptoms, gender and age (women/young) is important.
Here’s the different types for future reference, credit to Attia et al., of course:
Supply/demand mismatch (SSDM): a mismatch between the amount of oxygen that is supplied and the amount needed, often resulting from artery narrowing due to stable atherosclerotic plaque, but also potentially caused by anemia or fast, irregular heartbeats and hypotension.
Spontaneous coronary artery dissection (SCAD): a tear within the coronary artery wall that restricts blood flow.
Coronary embolism: a clot traveling through circulation and blocking a coronary artery, which can sometimes result from atherosclerotic plaques moving more distally in circulation.
Vasospasm: a transient constriction of a coronary vessel that sharply limits blood flow.
Myocardial infarction with non-obstructed coronary arteries-unknown (MINOCA-U): a term to describe heart attacks for which no clear cause is identified (i.e., a patient shows a diagnostic electrocardiogram signal but not significant coronary obstruction is detected).
Myopericarditis: inflammation involving both the myocardium (heart muscle) and the pericardium (the sac surrounding the heart).
Takotsubo syndrome: stress-induced weakening and ballooning of the heart muscle (the left ventricle).
It would be interesting to know how aging affects this, and what percent of CVD these would take up in a zero plaque world over time, i.e if they are bottlenecks.