Short answers, pulled from the story.
Silent heart attacks account for between 22 and 64 percent of all myocardial infarctions. These cases are often discovered only during an autopsy or through routine electrocardiogram tests performed years later. This phenomenon is particularly prevalent among the elderly and those suffering from diabetes.
A myocardial infarction is caused by a violent rupture of an atherosclerotic plaque that has been silently building up for decades. This rupture exposes the cholesterol core to blood flow, triggering the rapid formation of a blood clot or thrombus that blocks the artery within minutes. The process involves the release of oxygen radicals and the disruption of electrolyte balance within the heart cells.
Women are significantly more likely to report neck pain, arm pain, and extreme tiredness without any chest discomfort during a myocardial infarction. Studies indicate that women are less likely to report chest pain and more likely to experience nausea, jaw pain, and palpitations. About 30 percent of all heart attacks present with these atypical symptoms.
Percutaneous coronary intervention is ideally performed within 90 to 120 minutes of contact with a medical provider. If this window is missed, the patient may be treated with thrombolysis, a medication that activates enzymes to dissolve blood clots. Troponin levels rise within 2 to 3 hours of injury and peak within 1 to 2 days.
Genome-wide association studies have identified 27 genetic variants associated with an increased risk of heart attacks. The strongest link is found on chromosome 9 at locus 21, containing genes CDKN2A and 2B. Having a male first-degree relative who had a myocardial infarction before age 55 or a female first-degree relative before age 65 significantly increases risk.
Individuals living in low-socioeconomic areas experience myocardial infarctions twice as often as those in higher socioeconomic areas. In the United States, African Americans bear a greater burden of myocardial infarction and other cardiovascular events. South Asians experience higher rates of acute myocardial infarctions at younger ages, largely explained by a higher prevalence of risk factors at younger ages.