|Year : 2019 | Volume
| Issue : 1 | Page : 18-25
Acute coronary syndrome in young - A tertiary care centre experience with reference to coronary angiogram
Tammiraju Iragavarapu1, T Radhakrishna2, K Jagadish Babu1, R Sanghamitra1
1 Department of Cardiology, ASRAM Medical College, Eluru, Andhra Pradesh, India
2 Department of General Medicine, ASRAM Medical College, Eluru, Andhra Pradesh, India
|Date of Web Publication||2-May-2019|
Dr. Tammiraju Iragavarapu
Department of Cardiology, ASRAM Medical College, Eluru - 534 005, Andhra Pradesh
Source of Support: None, Conflict of Interest: None
Background: Acute coronary syndrome (ACS) is a potentially life-threatening condition which is more common in elderly people, and young are relatively protected. Currently, the protective effect on young from coronary artery disease (CAD) is taken away by several risk factors. The aim of this study is to determine the conventional risk factors and angiographic correlation of CAD in young age (<40 years) to that of elderly age (>40 years). Materials and Methods: This study was a hospital-based retrospective cross-sectional analytical study involving 1151 patients of ACS admitted in the cardiac ICU from May 2016 to May 2018. Among these patients, coronary risk factors such as smoking, diabetes, hypertension, dyslipidemia, and family history were studied. Patients were divided into two groups, Group A: <40 years and Group B: >40 years. Patients were evaluated angiographically. The significance of each risk factor between the groups was calculated by employing the Chi-square test and P < 0.05 was taken as statistically significant. Results: A total of 1151 cases were included in the study, of which 120 cases were <40 years of age. The prevalence of CAD in young in our study is 10.42% with male preponderance. P value is statistically significant (P < 0.05) among younger individuals for smoking, dyslipidemia, obesity, family history. Of 120 cases with critical CAD, single-vessel disease (SVD), predominantly the left anterior descending artery, was the most prevalent. SVD and recanalized coronaries were statistically significant among younger group whereas triple-vessel disease (TVD) is statistically significant among the elderly. Thrombus burden is more in young when compared to the elderly. Conclusion: Although ACS is a less common entity in young adults aged 40 years or less, recent epidemiological trend is progressing and it constitutes an important challenge both for a patient and for a treating physician. Young patients with CAD are mainly males, and SVD is more common. Emphasis should be given on diagnosis and management of risk factors in this vulnerable group to prevent mortality and morbidity.
Keywords: Acute coronary syndrome, left ventricular dysfunction, risk factors, single-vessel disease, young age
|How to cite this article:|
Iragavarapu T, Radhakrishna T, Babu K J, Sanghamitra R. Acute coronary syndrome in young - A tertiary care centre experience with reference to coronary angiogram. J Pract Cardiovasc Sci 2019;5:18-25
|How to cite this URL:|
Iragavarapu T, Radhakrishna T, Babu K J, Sanghamitra R. Acute coronary syndrome in young - A tertiary care centre experience with reference to coronary angiogram. J Pract Cardiovasc Sci [serial online] 2019 [cited 2019 May 23];5:18-25. Available from: http://www.j-pcs.org/text.asp?2019/5/1/18/257607
| Introduction|| |
Coronary artery disease (CAD) is an emerging health problem in India; various risk factors contribute to the increased prevalence of CAD in different age groups. Cardiovascular diseases (CVDs) and its complications account for approximately 12 million deaths annually in the Indian subcontinent. The Global Status Report on noncommunicable diseases (NCDs) has reported that in India, CVD caused more than 2.5 million deaths in 2008. The leading cause of NCD deaths in 2012 was CVD (17.5 million deaths, or 46.2% of NCD deaths). As per 2014 statistics by the World Health Organization, 26% of total mortality in India is contributed by CVD. Mortality due to CAD is higher in South India. The mean age for the first presentation of acute myocardial infarction (MI) in Indians is 53 years. Studies carried out in India, and other places suggest that Asians in general and Indians in particular are at an increased risk of MI at a younger age (<40 years). Heart diseases are rising in Asian Indians and present 5–10 years earlier than in other populations around the world.
Various studies had considered the age limit varying from 35 to 55 years in the spectrum of young CAD., The onset of CAD before 40 years of age is considered as premature CAD (PCAD).,
In our study, the incidence of CAD in young Indians is about 12%–16%, which is higher than any other ethnic group., Several studies were done analyzing the risk factors of CAD in young such as Multinational MONItoring of trends and determinants in CArdiovascular disease study, INTERHEART, and EURO HEART ACS epidemiologic studies, along with randomized controlled trials, have shown that certain risk factors such as family history, obesity, dyslipidemia, and use of tobacco products, are more potent predictors of outcomes in the young than in their older counterparts. Very limited data are available regarding the prevalence of various risk factors for CAD in younger patients in our part of South India (Andhra Pradesh). Keeping this in view, a preliminary study was carried out to compare the conventional risk factors in young and elderly in patients with ACS. This study also includes the assessment of critical CAD (>70% diameter stenosis) in both groups angiographically. To our knowledge, this is one of pioneer studies focusing on the assessment of conventional risk factors for CAD with angiographic analysis at a tertiary teaching hospital in this part of the country.
| Materials and Methods|| |
Based on the inclusion criteria, a total of 1151 acute coronary syndrome (ACS, ST-elevation myocardial infarction [STEMI], non-ST elevation myocardial infarction [NSTEMI], and unstable angina [USA]) patients admitted in the intensive critical care unit of the Department of Cardiology, ASRAM Medical College, between May 2016 and May 2018 after taking proper consent were included. Chronic stable angina patients and patients with ACS who did not undergo angiogram were excluded. The institutional ethical clearance was obtained. These study patients were divided into two groups; Group 1: <40 years of age and Group 2: >40 years of age. A detailed history (including personal and family history) and examination were noted. All patients were subjected to complete hematological and biochemical investigations including troponin-T and electrocardiogram for the evaluation of ACS. Among these patients, coronary risk factors such as smoking, diabetes mellitus, hypertension, dyslipidemia, gender, kidney disease, and angina class were studied. The body mass index (BMI) was also calculated for all the patients using Broca's formula. These patients were evaluated with echocardiogram for ejection fraction. Both the groups underwent coronary angiography (CAG) based on the American College of Cardiology/European Society of Cardiology indications for CAG., CAG was done through the right radial route using an optitorque catheter after taking patient's consent. Critical CAD was defined as 70% or more narrowing of a coronary artery that results in a significant reduction in maximum flow capacity in a distal vascular bed. The patients were grouped into single-vessel disease (SVD), double-vessel disease, and triple-vessel disease (TVD) according to the number of major epicardial coronary arteries (left anterior descending artery [LAD], left circumflex artery, and right coronary artery [RCA]) involved.
The statistical significance of each risk factor between the groups was done using GraphPad Software (Dr. Harvey Motulsky GraphPad Software 2365 Northside Dr. Suite 560 San Diego, CA) in which we used a frequency percentage and Chi-square with Yates' correction at the level of significance α = 0.05 (P < 0.05).
| Results|| |
Of the 1151 cases included in this study, 120 were in the younger age group (<40 years) contributing 10.42% of the total cases. The mean age of CAD in young is 36.11 years, the youngest being 22 years. The mean age of presentation of older group is 56.42 years. Male outnumbered females in both groups. Of the 120 patients in the younger group, there were 86 (71.66%) males and 34 (28.33%) females. In the older group, males and females contributed 59% (608) and 41% (423), respectively. The mean BMI in younger group is 28.2 ± 5.3, whereas in the older group, it is 25.8 ± 6.1. Of 120 cases, anterior wall MI contributes the major portion of ACSs (43.3%) followed by inferior wall MI (26.66%), NSTEMI (10.83%), and USA (10.83%). The same order of incidence is followed among the elderly group with anterior wall contributing to 32%. The baseline characteristics are presented in [Table 1].
Various risk factors such as diabetes, hypertension, dyslipidemia, smoking, obesity, and chronic kidney disease (CKD) have been studied extensively in these two groups. Risk factors for CAD among the young and elderly patients are summarized in [Table 2] and presented in [Figure 1] with statistical analysis.
|Table 2: Risk factors for acute coronary syndrome among young and elderly|
Click here to view
|Figure 1: Bar diagram showing the comparison of various risk factors among the two groups.|
Click here to view
Ejection fraction in both groups is tabulated in [Table 3]. In younger group, there is predominant moderate left ventricular (LV) dysfunction (35.83%) while severe LV dysfunction is extremely significant in older age group. The LV dysfunction profile is shown in [Figure 2] as a bar diagram.
|Table 3: Comparison of various classes of left ventricle dysfunction in two age groups|
Click here to view
|Figure 2: Bar diagram showing profile of left ventricular dysfunction among the two groups.|
Click here to view
Angiographic data are depicted in [Table 4]. SVD and recanalized coronaries were statistically significant among younger group (P < 0.05), whereas TVD is statistically significant among older group (P < 0.05). Thrombus burden is more in young when compared to the elderly. The predominant vessel involved in the younger and older groups is LAD contributing to 68.3% and 63.62%, respectively. [Figure 3] shows the pie diagram depiction of angiographic profile of the two groups.
|Table 4: Comparison of angiographic characteristics of acute coronary syndrome in age <40 years and >40 years|
Click here to view
| Discussion|| |
The global burden of CVDs is on rapid rise due to a predominant increase in the incidence and prevalence of the same in the developing countries. India, a developing nation, is following the same trend. During the past three decades, the prevalence of most of the cardiovascular risk factors including smoking, diabetes mellitus, hypertension, and dyslipidemia has increased markedly in India.,
About 25% of acute MI in India occurs under the age of 40 and 50% under the age of 50. One center in Kerala reported a 47-fold increase in the incidence of first MI under the age of 40 in the last 20 years. In general, MI develops 5–10 years earlier in Asian Indians than in other populations , and its occurrence in patients under 40 is 5- to 10-fold higher.
In Global Registry of Acute Coronary Events study, the prevalence of young ACS was 6.3%; in Thai ACS registry, it was 5.8%; in Spain registry, it was 7%. In our study, the prevalence of young ACS is 10.42%. In our study, a total of 120 patients were <40 years of age. Most of them had anterior MI, and these patients were treated more aggressively as compared to older patients. This is consistent with previous reports.,, Previous studies have shown that male gender is one of the classic risk factors for CAD., In our study, the incidence of ACS in young males is 71.66%. Our study also concurs with previous findings that overall risk factors were more likely in males when compared to females.
Family history of PCAD is an important risk factor for young CAD. It stresses the role of genes in the etiology of young CAD. Studies have shown that person with positive family history of PCAD tends to have severe coronary atherosclerosis and is a very strong predictor of future acute coronary event. Increased plaque content in coronary vessels is seen in individuals with positive family history of PCAD and increases the incidence of severe obstructive CAD. In a study done in London, Chen et al. had found family that history of CAD was 39% in young ACS patients. Cole et al. revealed that around 64% of young patients had a positive family history. Family history of CAD was found in 30% of our younger group.
Tobacco smoking is an important independent risk factor for CAD in young adults. Current smoking of >10 cigarettes or beedi a day is associated with a 6.7-fold increase in the risk of MI. The risk of CAD begins to decline within months of smoking cessation and disappears within 3–5 years. A few studies have estimated smoking prevalence at 28.5%–30% in Indians living in India. The effect of cigarette smoking on coronary risk factors is pervasive. Unfavorable effects include enhancement of platelet function. Platelet activation by cigarette smoking is linked to thrombosis formation, including onset of MI. Zimmerman et al. found a prevalence of smoking in 92% of young CAD patients. Mukherjee et al. found prevalence of smoking to be higher in those <40 years of age, compared to those of >40 years (58.7% vs. 43%). The proportion of smoking among young people has declined, but the overall proportion maintains a high ratio. Pais et al. have shown it to be the most dominant risk factor in Indian population studied. Our study showed that smoking is a major risk factor for CAD in both study groups. The prevalence of smoking was 25.8% in younger group of our study. Smoking is statistically significant among young adults when compared to the elderly. Our study also demonstrates that cigarette smoking was the dominant risk factor predisposing to an earlier onset of CAD, in line with previous studies.,
Indians are genetically prone to develop type-2 diabetes mellitus due to insulin resistance. Hyperinsulinemia in these patients accelerates the atherosclerotic process in the coronary arteries. Diabetes is second only to CAD as a health burden in India. During the past decade, the number of people with diabetes in India increased from 32 million to 50 million, and this figure may reach 87 million by 2030. Hyperinsulinemia, insulin resistance, and higher rate of prevalence of metabolic syndrome in people with type-2 diabetes were attributed to high coronary risk in South Asians., In our study, slightly higher incidence of diabetes was seen among the elderly group (20.9%) when compared to younger group (20%), but no statistical significance was noted when comparison was made among the two groups. This fact has been documented in a number of previous studies.
The exact mechanism through which systemic hypertension induces MI has not been studied in detail, but there is evidence that hypertension causes LV hypertrophy and progression of atherosclerosis, resulting in CAD. Hypertension was revealed as a significant risk factor among the young in the studied population. This agrees with the previous studies by Sofia and EUROSPIRE, where hypertension has been seen as a major risk factor for CAD, but no statistical significance is attributed.
Dyslipidemia is defined as total cholesterol (TC) >200 mg/dl, low-density lipoprotein (LDL) >100 mg/dl, triglycerides (TG) >150 mg/dl, high-density lipoprotein (HDL) <40 mg/dl, according to the NCEP-ATP3 guidelines. An elevated level of TC is the strongest risk factor for CAD. A recent large study has shown an 8-fold higher CAD mortality with an increase in TC from <160 to >280 mg/dL among young Americans. An 88 mg/dL increase in TG levels significantly increases the relative risk (RR) of CAD by 30% in men and 75% in women. Low HDL is associated with increased risk of CAD even if TG and TC levels are not elevated. A 10 mg/dL decrease in HDL confers the same risk for CAD as 30 mg/dL increase in LDL. Low HDL with or without high TG is very common among Indians and genetic factors may be involved. Conversely, people with low TG-high HDL levels have a low risk of CAD, but this profile is uncommon among Asian Indians.
It is documented that South Asians have TC and LDL-cholesterol levels comparable to Afro-Caribbean's and Whites, but they do have higher TG and low HDL-cholesterol levels. Although dyslipidemia is an important risk factor for young CAD, there seems to be a little difference in the prevalence of lipid abnormalities in younger and elderly. One study demonstrated a significantly increased level of LDL and TC in persons of CAD >55 years of age when compared to <55 years of age. Conversely, in another study, there is high prevalence of lipid abnormalities in young CAD when compared to older group. These differences in lipid parameters may be due to effect of dietary, genetic, and environmental factors on lipid metabolism. Studies on epidemiological data from angiographically proven cases of PCAD (≤40 years) in native Indians suggest hyperlipidemia as the most prevalent risk factor., In our study, the fasting lipid profile tests revealed evidence of dyslipidemia in 17.5% of the young patients and 9% of the elderly subjects. This is statistically significant among younger group. The proposed reason of elderly patients having less incidence of abnormal lipids in our study is that most of the patients were already using some form of lipid-lowering drugs prescribed earlier.
Obesity is associated with increased risk of hypertension, diabetes, dyslipidemia, and CAD. Marked adverse metabolic consequences are seen with central (android or apple-type), but rarely with gluteo-femoral (gynoid or pear-type) obesity. Sagittal abdominal diameter to skin fold ratio seems to be a good indicator in predicting PCAD, even better than BMI and waist circumference. Obesity is a well-established risk factor for CAD, particularly in urban India. From previous studies, there is little difference in the prevalence of obesity in young CAD when compared to older CAD patients. In view of obesity as the risk factor for CAD, based on the BMI, our study showed statistically significant prevalence of higher BMI in Group 1 (<40 years) compared to Group 2 (>40 years). Although most of the comorbidities relating obesity to CAD increase as BMI increases, they also relate to body fat distribution. Asians have a higher body fat percentage for a given BMI than other ethnic groups and a different fat distribution pattern and are more prone to central obesity at low BMI levels. It might indicate that obesity as such not only relates to but also independently predicts coronary atherosclerosis. High-intensity aerobic exercise  and moderate alcohol intake have been known to reduce risk of CAD and MI.
Our study also showed that elderly patients with CKD had an 11% prevalence of CAD. In 1998, the U.S. National Kidney Foundation Task Force on Cardiovascular Disease in Chronic Renal Disease recommended that patients with CKD be considered to belong to the highest risk group for the development of cardiovascular events. These patients present unique challenges to physicians attempting to manage concomitant ischemic heart and CKD.
We observed an age-dependent variation in hazard associated with smoking and hypertension, with greater relative hazard in the youngest cohort of patients. However, diabetes mellitus and kidney disease were more prevalent in elderly patients in this study. Finally, in our study, significant risk factors in younger age group were found to be family history, smoking, dyslipidemia, and obesity. The CLARIFY registry shows a high prevalence and poor control of cardiovascular risk factors in patients from India. Efforts to improve risk factor control are required. All the studies comparing risk factor profiles are tabulated in [Table 5].
|Table 5: Comparative studies of various risk profile studies in young coronary artery disease|
Click here to view
In our study, younger group showed predominantly moderate LV dysfunction (35.83%), whereas in the elderly, severe LV dysfunction is predominant (49.8%). This is consistent with results from other studies., Cole et al. had identified average ejection fraction of 55% in young adults.
ACS in young, based on angiographic characteristics, can be due to atherosclerotic and nonatherosclerotic CAD which includes arteritis, thrombosis, embolization, and spasm (cocaine abuse). Coronary artery thrombus can be seen in hypercoagulable states such as protein C and S deficiency, antiphospholipid antigen (APLA), and nephrotic syndrome.,,
In our study, all 120 young patients underwent coronary angiogram. Coronary angiographic data showed statistically significant predominance of SVD in 67.5% young adults which is in accordance with Pathak et al., Suresh et al., and al-Koubaisy et al. Recanalized coronaries were seen in 15.8% of young patients which is concordant with other studies such as Maroszyńska-Dmoch et al., Sricharan et al., and Noor et al. Thrombus burden is more in young when compared to elderly. The predominant vessel involved in younger age group is LAD contributing to 68.3%, which is in concordance with angiographic studies such as Badran et al. and Ahmed Hussein. However, Kennelly et al. have found that RCA was the most common artery involved in their study done in 1982. There is only 3.3% of TVD in our study which is in accordance with Jamil et al. and Sricharan et al.
All the studies showing angiographic data in young adult are depicted in [Table 6] with appropriate references.
|Table 6: Comparative studies of angiographic profile in young acute coronary syndrome patients|
Click here to view
- It is an observational study so that certain confounding variables could have played role
- Some of the factors such as family history of coronary heart disease may have bias
- Some of the patients were already using lipid-lowering agents, so exact prevalence of dyslipidemia could not be traced
- We have analyzed the patients who reached the hospital, so it might not be a true representative of the population
- This was a single-center study. Hence, the results cannot be generalized to the community
- This is a retrospective study of data collected from the case records, and the details of bifurcation lesions and ostial lesions could not be extracted
- Utilization of thrombolytic therapy could have potentially affected our results as far as the higher incidence of normal coronary arteries is concerned
- We also could not do any genetic studies
- As in many other studies, we have used eye-balling to grade angiographic stenosis.
| Conclusion|| |
Although ACS, fortunately, is an uncommon entity in young adults aged 40 years or less, it constitutes an important challenge for both a patient and a treating physician. Prevention and control of premature cardiovascular diseases in India need urgent control of these factors. Smoking turned out to be the major risk factor which needs strict prevention. Target oriented control of hypertension, obesity, lipid levels, and glycemia are required. Young patients with ACS are mainly males, and SVD is more common with large thrombus burden. Younger group has predominance of moderate LV dysfunction, whereas, in the older group, there is predominance of severe LV dysfunction. Emphasis should be given to educating the young on the management of these risk factors to decrease mortality and morbidity related to ACS.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Gupta R, Guptha S, Sharma KK, Gupta A, Deedwania P. Regional variations in cardiovascular risk factors in India: India heart watch. World J Cardiol 2012;4:112-20.
World Health Organization. Global Status Report on Noncommunicable Diseases 2014. Geneva: World Health Organization; 2014.
Sharma M, Ganguly NK. Premature coronary artery disease in Indians and its associated risk factors. Vasc Health Risk Manag 2005;1:217-25.
Yusuf S, Hawken S, Ounpuu S, Dans T, Avezum A, Lanas F, et al.
Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): Case-control study. Lancet 2004;364:937-52.
Hoit BD, Gilpin EA, Henning H, Maisel AA, Dittrich H, Carlisle J, et al.
Myocardial infarction in young patients: An analysis by age subsets. Circulation 1986;74:712-21.
Prajapati J, Jain S, Virpariya K, Rawal J, Joshi H, Sharma K, et al.
Novel atherosclerotic risk factors and angiographic profile of young Gujarati patients with acute coronary syndrome. J Assoc Physicians India 2014;62:584-8.
Siddique MA, Shrestha MP, Salman M. Age related differences of risk profile and angiographic findings in patients with coronary heart disease. BSMMU J 2010;3:13-7.
Mammi MV, Pavithran K, Abdu Rahiman P, Pisharody R, Sugathan K. Acute myocardial infarction in North Kerala – A 20 year hospital based study. Indian Heart J 1991;43:93-6.
Mähönen MS, McElduff P, Dobson AJ, Kuulasmaa KA, Evans AE; WHO MONICA Project. Current smoking and the risk of non-fatal myocardial infarction in the WHO MONICA project populations. Tob Control 2004;13:244-50.
Rosengren A, Wallentin L, Simoons M, Gitt AK, Behar S, Battler A, et al.
Age, clinical presentation, and outcome of acute coronary syndromes in the Euroheart acute coronary syndrome survey. Eur Heart J 2006;27:789-95.
Task Force on Myocardial Revascularization of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS), European Association for Percutaneous Cardiovascular Interventions (EAPCI), Wijns W, Kolh P, Danchin N, Di Mario C, et al.
Guidelines on myocardial revascularization. Eur Heart J 2010;31:2501-55.
Levine GN, Bates ER, Blankenship JC, Bailey SR, Bittl JA, Cercek B, et al.
2011 ACCF/AHA/SCAI guideline for percutaneous coronary intervention: A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Society for Cardiovascular Angiography and Interventions. Circulation 2011;124:e574-651.
Shah I, Faheem M, Shah I, Faheem M, Shahzeb R, Hafizullah M. Clinical profile, angiographic characteristics and treatment recommendations in patients with coronary artery disease. J Pak Med Stud 2013;3:94-100.
Kasliwal RR, Kulshreshtha A, Agrawal S, Bansal M, Trehan N. Prevalence of cardiovascular risk factors in Indian patients undergoing coronary artery bypass surgery. J Assoc Physicians India 2006;54:371-5.
Gupta R. Meta-analysis of prevalence of hypertension in India. Indian Heart J 1997;49:43-8.
Avezum A, Makdisse M, Spencer F, Gore JM, Fox KA, Montalescot G, et al.
Impact of age on management and outcome of acute coronary syndrome: Observations from the Global Registry of Acute Coronary Events (GRACE). Am Heart J 2005;149:67-73.
Tungsubutra W, Tresukosol D, Buddhari W, Boonsom W, Sanguanwang S, Srichaiveth B, et al.
Acute coronary syndrome in young adults: The Thai ACS registry. J Med Assoc Thai 2007;90 Suppl 1:81-90.
Morillas P, Bertomeu V, Pabón P, Ancillo P, Bermejo J, Fernández C, et al.
Characteristics and outcome of acute myocardial infarction in young patients. The PRIAMHO II study. Cardiology 2007;107:217-25.
von Eyben FE, Bech J, Madsen JK, Efsen F. High prevalence of smoking in young patients with acute myocardial infarction. J R Soc Health 1996;116:153-6.
Jörgensen S, Köber L, Ottesen M, Torp-Pedersen C, Videbaek J, Kjøller E. The prognostic importance of smoking status at the time of acute myocardial infarction in 6676 patients. J Cardiovasc Risk 1999;6:23-7.
Pfeffer MA, McMurray J, Leizorovicz A, Maggioni AP, Rouleau JL, Van De Werf F, et al.
Valsartan in acute myocardial infarction trial (VALIANT): Rationale and design. Am Heart J 2000;140:727-50.
Kalin MF, Zumoff B. Sex hormones and coronary disease: A review of the clinical studies. Steroids 1990;55:330-52.
Assmann G, Cullen P, Jossa F, Lewis B, Mancini M. Coronary heart disease: Reducing the risk: The scientific background to primary and secondary prevention of coronary heart disease. A worldwide view. International Task Force for the Prevention of Coronary Heart Disease. Arterioscler Thromb Vasc Biol 1999;19:1819-24.
Otaki Y, Gransar H, Berman DS, Cheng VY, Dey D, Lin FY, et al.
Impact of family history of coronary artery disease in young individuals (from the CONFIRM registry). Am J Cardiol 2013;111:1081-6.
Chen L, Chester M, Kaski JC. Clinical factors and angiographic features associated with premature coronary artery disease. Chest 1995;108:364-9.
Cole JH, Miller JI 3rd
, Sperling LS, Weintraub WS. Long-term follow-up of coronary artery disease presenting in young adults. J Am Coll Cardiol 2003;41:521-8.
Pais P, Pogue J, Gerstein H, Zachariah E, Savitha D, Jayprakash S, et al.
Risk factors for acute myocardial infarction in Indians: A case-control study. Lancet 1996;348:358-63.
Jindal SK, Aggarwal AN, Chaudhry K, Chhabra SK, D'Souza GA, Gupta D, et al.
Tobacco smoking in India: Prevalence, quit-rates and respiratory morbidity. Indian J Chest Dis Allied Sci 2006;48:37-42.
Inoue T. Cigarette smoking as a risk factor of coronary artery disease and its effects on platelet function. Tob Induc Dis 2004;2:27-33.
Zimmerman FH, Cameron A, Fisher LD, Ng G. Myocardial infarction in young adults: Angiographic characterization, risk factors and prognosis (Coronary Artery Surgery Study Registry). J Am Coll Cardiol 1995;26:654-61.
Mukherjee D, Hsu A, Moliterno DJ, Lincoff AM, Goormastic M, Topol EJ. Risk factors for premature coronary artery disease and determinants of adverse outcomes after revascularization in patients < or =40 years old. Am J Cardiol 2003;92:1465-7.
Ma E, Iso H, Takahashi H, Yamagishi K, Tanigawa T. Age-period-cohort analysis of mortality due to ischemic heart disease in Japan, 1955 to 2000. Circ J 2008;72:966-72.
Yildirim N, Arat N, Doǧan MS, Sökmen Y, Ozcan F. Comparison of traditional risk factors, natural history and angiographic findings between coronary heart disease patients with age <40 and >or=40 years old. Anadolu Kardiyol Derg 2007;7:124-7.
Mohan V, Radhika G, Vijayalakshmi P, Sudha V. Can the diabetes/cardiovascular disease epidemic in India be explained, at least in part, by excess refined grain (rice) intake? Indian J Med Res 2010;131:369-72.
] [Full text]
McKeigue PM, Ferrie JE, Pierpoint T, Marmot MG. Association of early-onset coronary heart disease in South Asian men with glucose intolerance and hyperinsulinemia. Circulation 1993;87:152-61.
Mohan V, Sandeep S, Deepa R, Shah B, Varghese C. Epidemiology of type 2 diabetes: Indian scenario. Indian J Med Res 2007;125:217-30.
] [Full text]
Rakugi H, Yu H, Kamitani A, Nakamura Y, Ohishi M, Kamide K, et al.
Links between hypertension and myocardial infarction. Am Heart J 1996;132:213-21.
Kotseva K, Wood D, De Backer G, De Bacquer D, Pyörälä K, Keil U. EUROASPIRE III: A survey on the lifestyle, risk factors and use of cardioprotective drug therapies in coronary patients from 22 European countries. Heart 2009;95:4.
Stone NJ, Robinson JG, Lichtenstein AH, Bairey Merz CN, Blum CB, Eckel RH, et al.
2013 ACC/AHA guideline on the treatment of blood cholesterol to reduce atherosclerotic cardiovascular risk in adults: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation 2014;129:S1-45.
Stamler J, Daviglus ML, Garside DB, Dyer AR, Greenland P, Neaton JD, et al.
Relationship of baseline serum cholesterol levels in 3 large cohorts of younger men to long-term coronary, cardiovascular, and all-cause mortality and to longevity. JAMA 2000;284:311-8.
Bainton D, Miller NE, Bolton CH, Yarnell JW, Sweetnam PM, Baker IA, et al.
Plasma triglyceride and high density lipoprotein cholesterol as predictors of ischaemic heart disease in British men. The Caerphilly and Speedwell Collaborative Heart Disease studies. Br Heart J 1992;68:60-6.
Miller M, Rhyne J, Khatta M, Parekh H, Zeller K. Prevalence of the APOC3 promoter polymorphisms T-455C and C-482T in Asian-Indians. Am J Cardiol 2001;87:220-1, A8.
Hatmi ZN, Mahdavi-Mazdeh M, Hashemi-Nazari SS, Hajighasemi E, Nozari B, Mahdavi A, et al.
Pattern of coronary artery disease risk factors in population younger than 55 years and above 55 years: A population study of 31999 healthy individuals. Acta Med Iran 2011;49:368-74.
Sinha N, Kumar S, Rai H, Singh N, Kapoor A, Tewari S, et al.
Patterns and determinants of dyslipidaemia in 'young' versus 'not so young' patients of coronary artery disease: A multicentric, randomised observational study in Northern India. Indian Heart J 2012;64:229-35.
Mohan V, Deepa R, Rani SS, Premalatha G; Chennai Urban Population Study (CUPS No. 5). Prevalence of coronary artery disease and its relationship to lipids in a selected population in South India: The Chennai urban population study (CUPS no 5). J Am Coll Cardiol 2001;38:682-7.
Goel PK, Bharti BB, Pandey CM, Singh U, Tewari S, Kapoor A, et al.
A tertiary care hospital-based study of conventional risk factors including lipid profile in proven coronary artery disease. Indian Heart J 2003;55:234-40.
Vasheghani-Farahani A, Majidzadeh AK, Masoudkabir F, Karbalai S, Koleini M, Aiatollahzade-Esfahani F, et al.
Sagittal abdominal diameter to triceps skinfold thickness ratio: A novel anthropometric index to predict premature coronary atherosclerosis. Atherosclerosis 2013;227:329-33.
McKeigue PM, Shah B, Marmot MG. Relation of central obesity and insulin resistance with high diabetes prevalence and cardiovascular risk in South Asians. Lancet 1991;337:382-6.
Ehsani AA, Heath GW, Hagberg JM, Sobel BE, Holloszy JO. Effects of 12 months of intense exercise training on ischemic ST-segment depression in patients with coronary artery disease. Circulation 1981;64:1116-24.
Levey AS, Beto JA, Coronado BE, Eknoyan G, Foley RN, Kasiske BL, et al.
Controlling the epidemic of cardiovascular disease in chronic renal disease: What do we know? What do we need to learn? Where do we go from here? National Kidney Foundation Task Force on Cardiovascular Disease. Am J Kidney Dis 1998;32:853-906.
Kaul U, Natrajan S, Dalal J, Saran RK. Prevalence and control of cardiovascular risk factors in stable coronary artery outpatients in India compared with the rest of the world: An analysis from international CLARIFY registry. Indian Heart J 2017;69:447-52.
Kannel WB. Incidence and epidemiology of heart failure. Heart Fail Rev 2000;5:167-73.
Rosamond W, Flegal K, Furie K, Go A, Greenlund K, Haase N, et al.
Heart disease and stroke statistics–2008 update: A report from the American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Circulation 2008;117:e25-146.
Manzar KJ, Padder FA, Conrad AR, Freeman I, Jonas EA. Acute myocardial infarction with normal coronary artery: A case report and review of literature. Am J Med Sci 1997;314:342-5.
Penny WJ, Colvin BT, Brooks N. Myocardial infarction with normal coronary arteries and factor XII deficiency. Br Heart J 1985;53:230-4.
Hamsten A, Norberg R, Björkholm M, de Faire U, Holm G. Antibodies to cardiolipin in young survivors of myocardial infarction: An association with recurrent cardiovascular events. Lancet 1986;1:113-6.
Pathak V, Ruhela M, Chadha N. Risk factors, angiographic characterization and prognosis in young adults presented with acute coronary syndrome at a tertiary care center in North India. BMR Med 2016;3:1-5.
Suresh G, Subramanyam K, Kudva S. Coronary artery disease in young adults: Angiographic study – A single center experience. Heart India 2016;4:132-5. [Full text]
al-Koubaisy OK, Mehdi RS, Arem FD, Ahmed IT. Cine angiographic findings in young Iraqi men with first acute myocardial infarction. Cathet Cardiovasc Diagn 1990;19:87-90.
Maroszyńska-Dmoch EM, Wożakowska-Kapłon B. Clinical and angiographic characteristics of coronary artery disease in young adults: A single centre study. Kardiol Pol 2016;74:314-21.
Sricharan KN, Rajesh S, Rashmi, Meghana HC, Badiger S, Mathew S. Study of acute myocardial infarction in young adults: Risk factors, presentation and angiographic findings. J Clin Diagn Res 2012;3853:1995.
Noor L, Adnan Y, Dar MH, Ali U, Ahmad F, Awan ZA. Characteristics of the coronary arterial lesions in young patients with acute myocardial infarction. Khyber Med Univ J 2018;10:81-5.
Badran HM, Elnoamany MF, Khalil TS, Eldin MM. Age-related alteration of risk profile, inflammatory response, and angiographic findings in patients with acute coronary syndrome. Clin Med Cardiol 2009;3:15-28.
Ahmed Hussein AM. Coronary artery disease in young versus older adults in Hilla city: Prevalence, clinical characteristics and angiographic profile. Karbala J Med 2012;5:1328-33.
Kennelly BM, Gersh BJ, Lane GK, Beck W. The relationship between angiographic findings and risk factors in young men with myocardial infarction. S Afr Med J 1982;61:508-12.
Jamil G, Jamil M, Alkhazraji H, Haque A, Chedid F, Balasubramanian M, et al.
Risk factor assessment of young patients with acute myocardial infarction. Am J Cardiovasc Dis 2013;3:170-4.
Wolfe MW, Vacek JL. Myocardial infarction in the young. Angiographic features and risk factor analysis of patients with myocardial infarction at or before the age of 35 years. Chest. 1988;94:926
Barbash GI, White HD, Modan M, Diaz R, Hampton JR, Heikkila J, et al
. AAcute myocardial infarction in the young--the role of smoking. The Investigators of the International Tissue Plasminogen Activator/Streptokinase Mortality Trial. Eur Heart J 1995;16:313-6.
Christus T, Shukkur AM, Rashdan I, Koshy T, Alanbaei M, Zubaid M, et al.
Coronary artery disease in patients aged 35 or less – A different beast? Heart Views 2011;12:7-11.
] [Full text]
Bhardwaj R, Kandoria A, Sharma R. Myocardial infarction in young adults-risk factors and pattern of coronary artery involvement. Niger Med J 2014;55:44-7.
] [Full text]
Jayachandra S, Agnihotram G, Rao RP, Murthy CV. Risk-factor profile for coronary artery disease among young and elderly patients in Andhra Pradesh. Heart India 2014;2:11-4. [Full text]
Wang X, Gao M, Zhou S. Trend in young coronary artery disease in China from 2010 to 2014: A retrospective study of young patients ≤ 45. BMC Cardiovasc Disord 2017;17:18.
[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]