A Comparative Study of Coronary Atherosclerosis in Young and Old

Young and older patients with acute myocardial infarction: differences in risk factors and angiographic characteristics

OBJECTIVE

Although coronary artery disease mainly affects older individuals, the incidence of myocardial infarction (MI) among younger adults (<55 years) has increased during the past decade. Young and older MI patients have different underlying pathophysiologic characteristics, atherosclerotic plaque morphology, and risk factor profiles.

METHODS

We studied 977 patients (≤55 years old: 322, >55 years old: 655) who were hospitalized for MI in the previous 5 years. Patients' baseline characteristics and daily habits were recorded. Angiographic characteristics and vascular lesions were detected, and further examinations, including flow-mediated dilation (FMD), pulse wave velocity (PWV), and central augmentation index (AIx), were performed. Biomarkers of inflammation (Interleukin-6, Tumor-Necrosis factor-a, Intercellular Adhesion Molecule 1, and Osteopontin) were also tested.

RESULTS

The median age in the younger age group was 49 years [interquartile range (IQR: 44-53)] and 66 years (IQR: 61-73) in the older age group. Arterial hypertension was less prevalent in the young compared to the elderly with MI (47.4% vs. 76.2%, p < 0.01). The younger counterparts presented significantly lower rates of diabetes mellitus (19.3% vs. 30.6%, p < 0.01), dyslipidemia (59% vs. 70.8%, p < 0.01), and atrial fibrillation (2.6% vs. 9.7%, p < 0.01) and were more casual smokers (49.3% vs. 23.8%, p < 0.01) compared to older patients with MI. In terms of arterial stiffness, lower PWV [7.3 m/s (IQR: 6.5-8.4 m/s) vs. 9 m/s (IQR: 8-10.8 m/s), p < 0.01] and AIx (20.5 ± 10.8 vs. 25.5 ± 7.8, p < 0.01) were recorded in the young compared to the elderly with MI. Concerning angiographic characteristics, younger patients were more likely to have none or single-vessel disease (55.6% vs. 45.8%, p < 0.02), whereas the older participants more frequently had three or more vessel disease (23.5% vs. 13.6% in the young, p < 0.02). Although significant disparities in blood test results were detected during the acute phase, the great majority of young MI patients were undertreated.

CONCLUSION

Younger patients with MI are more likely to be smokers with impaired PWV measures, present with non-obstructive or single-vessel disease, and often remain undertreated. A better knowledge of the risk factors as well as the anatomic and pathophysiologic processes in young adults will help enhance MI prevention and treatment options in this patient population.

Increasing Incidence of ST-Elevation Acute Coronary Syndrome in Young South Asian Population, a Challenge for the World? An Assessment of Clinical and Angiographic Patterns and Hospital Course of Premature Acute Myocardial Infarction

The incidence of premature ischemic heart disease (IHD) is increasing because of urbanization, a sedentary lifestyle, and various other unexplored factors, especially in South Asia. This study aimed to assess the distribution of premature ST-elevation acute coronary syndrome (STE-ACS) with its clinical and angiographic pattern along with hospital course in a contemporary cohort of patients who underwent primary percutaneous intervention at a tertiary care center in the South Asian region. We included consecutive patients of either gender diagnosed with STE-ACS and who underwent primary percutaneous intervention. Patients were stratified based on age as ≤40 years (young) and >40 years (old). Clinical characteristics, angiographic patterns, and hospital course were compared between the 2 groups. Of the total of 4,686 patients, 466 (9.9%) were young (≤40 years). Young patients had a lower prevalence of hypertension (40.8% vs 54.5%, p <0.001), diabetes (26.6% vs 36.4%, p <0.001), metabolic syndrome (14.8% vs 24%, p <0.001), history of IHD (5.8% vs 9.3%, p = 0.013) and a higher frequency of smoking (33% vs 24.7%, p <0.001), positive family history (8.2% vs 3.2%, p <0.001), and single-vessel involvement (60.1% vs 33.2%, p <0.001). The composite adverse clinical outcome occurrence was significantly lower in young patients (14.2% vs 19.5%, p = 0.006). On multivariable analysis, history of IHD in young, whereas age, Killip class III/IV, intubated, arrhythmias on arrival, diabetes, history of IHD, pre-procedure left ventricular end-diastolic pressure, ejection fraction <40%, and slow flow/no-reflow during the procedure were found to be the independent predictors of adverse clinical outcome in old patients. In conclusion, we have a substantial burden of premature STE-ACS, mostly in male patients potentially driven by smoking and positive family history. Despite favorable pathophysiology, with mostly single-vessel hospital courses of STE-ACS in the young equally lethal in nature.

Role of Matrix Metalloproteinase-2 in the Development of Atherosclerosis among Patients with Coronary Artery Disease

Coronary artery disease (CAD) is a caused by atherosclerotic plaque buildup in the coronary arteries that supply blood and oxygen to the heart. Matrix metalloproteinase (MMP) is a family of zinc-dependent endopeptidase that is involved in various stages of atherosclerosis as demonstrated in in vitro and in vivo studies. MMP-2 is associated with both stable and unstable atherosclerotic plaque formation. The current review aimed to identify the role of MMP-2 in atherosclerosis development among CAD patients. Literature search was conducted through four online databases and only studies that were published from 2018 until February 2023 were included. The risk of bias was assessed by using the Newcastle-Ottawa Scale. A total of 10,622 articles were initially identified, and only eight studies that fulfilled the selection criteria were included in this review. The results showed that MMP-2 levels and activity were higher in patients with unstable CAD than those with stable CAD and healthy subjects. There was a significant association between MMP-2 levels and cardiovascular disease with MMP-14 levels, which is a pro-MMP-2 activator. In addition, two single nucleotide polymorphisms of the MMP-2 gene (rs243865 and rs243866) were significantly associated with the development of atherosclerosis. In conclusion, MMP-2 plays a crucial role in the development of atherosclerosis among patients with CAD and could be a potential target for CAD therapy.

Non-invasive coronary imaging in elderly population

Age is a non-modifiable cardiovascular risk factor, which leads to development and progression of chronic conditions, such as coronary artery disease, by promoting atherosclerosis. Aging is responsible for morphological structure changes of the coronary arteries and specific atherosclerotic plaque features, which can be studied with non-invasive coronary imaging techniques, particularly coronary CT angiography. The aim of this review is to evaluate current knowledge on this technique applied to the elderly population, and to describe CAD manifestation and plaque features of coronary atherosclerosis in this particular set of patients. We also discuss the clinical implication of frailty assessment and customization of diagnostic strategies in order to shift the approach from disease-centered to patient-centered care.

Acute Coronary Syndromes Due to Atherosclerotic Coronary Artery Disease in Young Patients

Young patients represent about 4-10% of the population presenting with acute coronary syndrome. In this focused mini-review, we highlight the data regarding acute coronary syndromes in young patients with atherosclerotic coronary artery disease. Differences in the underlying pathologies and pathophysiological mechanisms should yield to different clinical management and treatment strategies.

Risk factors profile of young and older patients with myocardial infarction

Myocardial infarction (MI) among young adults (<45 years) represents a considerable proportion of the total heart attack incidents. The underlying pathophysiologic characteristics, atherosclerotic plaque features, and risk factors profile differ between young and older patients with MI. This review article discusses the main differences between the younger and elderly MI patients as well as the different pathogenic mechanisms underlying the development of MI in the younger. Young patients with MI often have eccentric atherosclerotic plaques with inflammatory features but fewer lesions, and are more likely to be smokers, obese, and have poor lifestyle, such as inactivity and alcohol intake. Compared to older MI patients, younger are more likely to be men, have familial-combined hyperlipidaemia and increased levels of lipoprotein-a. In addition, MI in younger patients may be related to use of cannabis, cocaine use, and androgenic anabolic steroids. Genomic differences especially in the pathways of coagulation and lipid metabolism have also been identified between young and older patients with MI. Better understanding of the risk factors and the anatomic and pathophysiologic processes in young adults can improve MI prevention and treatment strategies in this patient group. Awareness could help identify young subjects at increased risk and guide primary prevention strategies. Additional studies focusing on gene pathways related to lipid metabolism, inflammation, and coagulation are needed.

The Effects of Calculated Remnant-Like Particle Cholesterol on Incident Cardiovascular Disease: Insights from a General Chinese Population

Background: Growing evidence suggests that remnant cholesterol (RC) contributes to residual atherosclerotic cardiovascular disease (ASCVD) risk. However, the cutoff points to treat RC for reducing ASCVD are still unknown. This study aimed to investigate the relationships between RC and combined cardiovascular diseases (CVDs) in a general China cohort, with 11,956 subjects aged ≥ 35 years. Methods: Baseline RC was estimated with the Friedewald formula for 8782 subjects. The outcome was the incidence of combined CVD, including fatal and nonfatal stroke and coronary heart disease (CHD). The Cox proportional hazards model was used to calculate hazard ratios (HRs) with 95% confidence intervals. The restricted cubic spline (RCS) model was used to evaluate the dose–response relationship between continuous RC and the natural log of HRs. Results: After a median follow-up of 4.66 years, 431 CVD events occurred. In the Cox proportional models, participants with a high level of categorial RC had a significantly higher risk for combined CVD (HR: 1.37; 95% CI: 1.07–1.74) and CHD (HR: 1.63; 95% CI: 1.06–2.53), compared to those with a medium level of RC. In the stratification analyses, a high level of RC significantly increased combined CVD risk for subgroups females, age < 65 years, noncurrent smokers, noncurrent drinkers, normal weight, renal dysfunction, and no hyperuricemia. The same trends were found for CHD among subgroups males, age < 65 years, overweight, renal dysfunction, and no hyperuricemia; stroke among subgroup females. In RCS models, a significant linear association between RC and combined CVD and a nonlinear association between RC and CHD resulted. The risk of outcomes was relatively flat until 0.84 mmol/L of RC and increased rapidly afterwards, with an HR of 1.308 (1.102 to 1.553) for combined CVD and 1.411 (1.061 to 1.876) for CHD. Stratified analyses showed a significant nonlinear association between RC and CVD outcomes in the subgroup aged < 65 years or the diabetes subgroup. Conclusions: In this large-scale and long-term follow-up cohort study, participants with higher RC levels had a significantly worse prognosis, especially for the subgroup aged 35–65 years or the diabetes mellitus subgroup.

Sudden death in a 39-year-old woman due to three-vessel coronary artery disease: A case report and literature review

Coronary atherosclerosis may be underestimated in previously asymptomatic and apparently healthy young people, although it has been reported in various epidemiological studies. Between 7% and 21% of sudden cardiac deaths in previously asymptomatic people aged <45 years are due to three-vessel coronary artery disease. So, clinical services need to vigilant for this condition. We report a single case of sudden death in a young woman who was affected by three-vessel coronary artery disease. This 39-year-old woman attended an emergency department for non-specific chest pain. After a brief observation period, in the absence of signs of an acute myocardial event, she self-discharged. However, she died suddenly the next day. The subsequent autopsy did not show significant pathological findings, although macroscopic examination of the heart revealed critical three-vessel coronary artery disease. Standard histological examination confirmed an atheromatous plaque obstructing >75% of the lumen of the anterior descending artery, complicated by haemorrhagic phenomena, with diffuse calcified and sub-totally occluded atherosclerotic plaques in the other vascular sections, without ischaemic signs of the cardiomyocytes or fibrosis. When young people present with chest pain, they must be carefully evaluated. Risks need to be clearly explained, particularly when self-discharge is requested.

The association of high-normal international-normalized-ratio (INR) with mortality in patients referred for coronary angiography

Aims

The international-normalized-ratio (INR) is typically used to monitor patients on warfarin or related oral anticoagulant therapy. The aim of our study was to investigate the association of the INR with mortality in coronary artery disease (CAD) patients not on oral anticoagulant therapy.

Methods and results

Between 1997 to 2000 the LUdwigshafen RIsk and Cardiovascular Health (LURIC) study enrolled 3316 patients of German ancestry that had been referred for coronary angiography. We excluded patients on coumarin therapy (n = 222) and patients with an INR more than 5 standard deviations (SD) away from the mean (n = 30). During a median follow-up of 9.9 years, 884 patients died, 547 patients from cardiovascular causes. After adjustment for cardiovascular risk factors the INR was associated with all-cause mortality in all patients and the CAD positive group with HRs (95% CI) of 1.14(1.07–1.21) and 1.16(1.09–1.23) per 1-SD increase, respectively. Adjustment for NT-proBNP rendered the association insignificant.

Conclusion

In LURIC, the INR was positively associated with mortality in patients with prevalent CAD not on oral anticoagulant therapy as well as in patients without CAD. Adjustment for NT-proBNP abolished the association suggesting clinical or subclinical heart failure strongly contributing to increased INR and higher mortality.

Pathology of atherosclerotic coronary artery disease in the young Indian population

Atherosclerotic coronary artery disease (CAD) is of great concern in young adults because of its potential to cause great incapacitation. This arena of cardiology has gained importance in South Asian countries, particularly India due to increased prevalence that is related to traditional risk factors, altered life styles and inherent risk factors. In this study, we sought to evaluate, at autopsy, the pathology of atherosclerotic CAD in young patients with ischemic heart disease (IHD). A 10-year retrospective autopsy-based study was carried out in a large tertiary-care centre and patients aged ≤45 years with IHD were selected. Out of 545 autopsied cases of IHD, 95 patients (17.4%) were young. Among these 95 patients, 84 (88.4%) had IHD related to atherosclerotic CAD; the youngest patient was 18 years old. Predictably there was sole involvement of left anterior descending artery and the presence of fibrous plaques. Irrespective of the plaque morphology, the commonest complication was thrombosis produced by plaque erosion seen in 36.9% of patients. Acute coronary insufficiency was noted in 52 patients (61.9%), while healed infarctions were surprisingly noted in 28 patients (33.3%). Screening for IHD in the young population may help to improve prognosis by detecting subclinical disease, although more studies are necessary to establish reference limits for this young population. Additional research must also focus on treatment concerns that are specific to young patients.

Manifestation of Coronary Atherosclerosis in Klang Valley, Malaysia: An Autopsy Study

Aims: The present study aimed to determine the epidemiological aspects of medico-legal autopsies and manifestation of coronary atherosclerosis.

Methods: This was a cross sectional study involving 222 cases recruited from National Institute of Forensic Medicine (NIFM) Hospital Kuala Lumpur (HKL) and Department of Forensic Medicine Hospital Sungai Buloh (HSgB) for a period of 15 months, from December 2012 to April 2014. Sociodemographic and autopsy findings, including the cause and manner of death were documented.

Results: Male and female subjects aged 18–70 years were recruited. Males contributed to 86% of the total subjects and comprised 61% of young adults. Road traffic accidents were the primary cause of death, contributing almost 50% of the subjects. One third of the cases comprised of death due to natural causes, wherein almost 75% of the subjects within this category succumbed to sudden cardiac death. Coronary artery disease (CAD) contributed to 60% of the sudden cardiac death (SCD). Single and double-vessel diseases were the most common pattern of atherosclerosis. In almost 80% of CAD cases, atherosclerosis affected the left anterior descending artery (LAD).

Conclusion: Cardiovascular diseases were the most significant natural cause of sudden death with a staggering figure of 75%. CAD was the single most commonly encountered pathology within the SCD. Most cases presented with single and double-vessel diseases, observed in all subjects, as well as the young adult population.

Use of cardiovascular age for assessing risks and benefits of menopausal hormone therapy

The Women's Health Initiative studies and others have suggested that menopausal hormone therapy may enhance the risk of new cardiovascular (CV) events in older women and diminish the development of coronary atherosclerosis in younger women. The underlying mechanisms to explain these findings are encapsulated in the term "Timing Hypothesis." Extensive pathophysiologic studies have provided mechanistic evidence for the dichotomous effects of estrogen on coronary artery vasculature. Early in the atherosclerotic disease process, estrogen exerts protective effects on the endothelium and retards plaque formation. Late in the process, estrogen causes plaque erosion or rupture with subsequent thrombosis and acute coronary events. Analysis of the Timing Hypothesis in women examined in the Women's Health Initiative primarily used chronologic age to assess divergent effects of estrogen. The complexity of the data underlying coronary pathophysiology has resulted in controversy whether MHT can be used in older women or those with prior CV disease. In a debate of this issue at a recent International Menopause Society meeting, the concept of using CV age rather than chronologic age was discussed as a practical method of resolving this issue and facilitating therapeutic decisions in older women. This "Personal Perspective" will review the concepts underlying CV age, describe how it is determined, provide support for its utility, and propose future studies using this parameter.

Risk Factors for Recurrent Cardiovascular Events Before Age 65 Years or Within 2.5 Years of a Recent First Cardiovascular Event

The aim of this study was to quantify the relation between classical risk factors (smoking, diabetes, BMI, waist circumference, blood pressure, and lipids), risk factor targets, and risk of recurrent major atherosclerotic cardiovascular events (MACE). This was first done for recurrent MACE ≤65 years in patients aged <60 years and second for recurrent MACE ≤2.5 years after a first cardiovascular event. Data were used from the Second Manifestations of Arterial Disease study (n = 5,115), a prospective cohort of patients with a recent (≤1 year) first cardiovascular event. During follow-up, 746 recurrent MACE occurred. Smoking (hazard ratio [HR] 1.43, 95% CI 1.11 to 1.84), diabetes (HR 1.83, 95% CI 1.11 to 1.84), diastolic blood pressure (>90 vs 70 to 90 mm Hg, HR 1.54, 95% CI 1.15 to 2.07), and high-density lipoprotein cholesterol (≤1.0 vs >1.0 mmol/L, HR 1.34, 95% CI 1.03 to 1.76) were related to increased risk of recurrent MACE ≤65 years in patients aged <60 years. Smoking (HR 1.65, 95% CI 1.23 to 2.22), physical inactivity (highest vs lowest tertile, HR 1.48, 95% CI 1.05 to 2.09), body mass index (per kg/m², HR 1.04, 95% CI 1.00 to 1.08), diastolic blood pressure (>90 vs 70 to 90 mm Hg, HR 1.61, 95% CI 1.17 to 2.21), low-density lipoprotein cholesterol (per mmol/L, HR 1.18, 95% CI 1.02 to 1.37), and non-high-density lipoprotein cholesterol (per mmol/L, HR 1.15, 95% CI 1.03 to 1.28) were related to recurrent MACE ≤2.5 years of follow-up. In conclusion, in patients with a recent cardiovascular event, smoking, blood pressure, and lipids are related to increased risk of recurrent cardiovascular events at young age or within a short time span, and intensive treatment of modifiable risk factors may contribute to prevent recurrent MACE in these patients.