In our study, we found no apparent difference in the presentation of AMI by sex. However, we contracted different symptom clusters in patients according to age. People younger than 40 years presented more with referred pain rather than chest pain, especially arm or shoulder pain, as opposed to older people who significantly presented with heavy chest pain. Middle-aged patients complained of referred pain to the left arm but rarely to the jaw, while people older than 60 years complained of referred pain mostly to the right arm. General symptoms such as diaphoresis was significant in patients older than 80 years, while neurological symptoms were rarely complained of by patients aged 50 to 59 years. As for the type of AMI, STEMI was the most common type but with no significance to either sex nor age groups. Conversely, patients on either end of age had significant relations with certain infarct locations. For patients younger than 40 years, right coronary artery occlusion rarely occurred, while extensive anterior and lateral infarctions were significantly associated with this age group. Whereas patients older than 80 years had strong relations to anteroapical infarction.
Our findings suggest that young people often complained of “atypical” presentation of AMI in contrast to older people who presented “typically” with chest pain and diaphoresis. Pain symptoms that are less associated with AMI, such as jaw or neck pain, epigastric pain and pain in either arm, were commonly seen in young patients. This can be due to the high portion of smokers in this age group which may alter the perception of pain in these patients. In addition to these patients having an otherwise healthy heart, which is more capable of maintaining adequate heart function when receiving suboptimal blood flow, this tempers their presentation of angina. On the other hand, older people are generally more prone to heart disease, hypertension and atherosclerosis. Thus, when encountering a sudden event of cardiac insult, it instantly breaks the cardiac compensation cycle which causes ischemic symptoms to progress rapidly. Clinically, this manifests as chest pain and diaphoresis which makes the presentation of AMI more pronounced and thus easily diagnosed. Different studies had conflicting results on this matter. A study involving 2586 patients with their first AMI found that reports of chest pain complaints decreased from the youngest to the oldest age group(16). While another study that was done following a clinical trial in Ireland reported that patients younger than 65 years were significantly more likely to experience chest pain, sweating, left arm pain, upset stomach and neck or jaw pain, compared with those older than 65(11). The EPIHeart cohort study also found similar results(17).
In our study, we found that diaphoresis, as part of general symptoms, had significance for patients older than 80 years. Whilst people in their forties usually complained of shortness of breath. A 2021 study found general symptoms to be the most commonly reported “atypical” symptoms of a first AMI in the oldest age group, such as shortness of breath, weakness and fatigue(16). Another study found a correlation between diabetes and the presentation of shortness of breath(18). Such contradiction could be attributed to the fact that general symptoms are usually tolerated and easily overlooked by patients. Thus, special care needs to be taken when encountering general symptoms complaints from young patients and those usually at low risk of AMIs.
Middle-aged patients rarely complained of jaw pain or neurological symptoms in our study. This can be due to the common onset of chronic diseases in this age group. Similar results were seen in the EPIHeart cohort study, which found that older women presented less frequently with chest pain and had chest pain and pain in other locations (mixed symptoms) more often than younger women(17).
Few studies were done on the location of infarction and its association with age and sex. In our study, we found a significant relation between lateral and extensive anterior infarctions in patients younger than 40 years old. Similarly, a study in 2014 involved 25538 STEMI patients older than 30 years, and found that women aged 30 to 49 years old had a significantly higher risk of anterior STEMI than men(19). In that same study, they found that anterior STEMI was age-dependent and increased after 60 years of age. This is in line with our finding that patients older than 80 years had a significant association with anteroapical infarction. A suggested reason for such results could be the prevalence of chronic stable coronary artery disease in old patients, which in turn increases subsequent collateral coronary circulation. This can explain why small anterior infarctions would go clinically unnoticed in older patients, which increases the proportion of young patients with anterior STEMIs.
On another note, young patients were found to be at a much lower risk for right coronary artery occlusion in our study. This included a lower incidence of inferior and posterior infarctions compared to older age groups. This finding is compatible with the fact that right coronary artery occlusion is usually the reason for STEMIs in old patients, especially with the increasing risk of total coronary occlusion with advancing age(20). Another study in Poland found that the right coronary artery occlusion was mostly responsible for STEMIs in men, but was irrelevant after age-adjustment analysis. Whilst women had a significant relation to the left anterior descending artery as a cause for STEMIs(21). Many studies raise conflicting theories on this matter, which opens the door for more recent and quality research.
Limitations:
Medical records of the last 2 years were retrieved from the 2 biggest central hospitals in the capital. However, men constituted most of our sample as males are constitutionally more prone to heart diseases than women. Due to the effects of war on Syria and the nature of public hospitals where delivery of medical care is free of charge, certain supplies are not readily available. Thus, patients in our study were diagnosed with AMI when they had appropriate clinical symptoms, ischemic ECG changes and deteriorating vital signs which improvement on the delivery of nitrates. This does not obviate the fact that high-sensitivity cardiac troponin provides a much more accurate diagnosis.