Acute myocardial infarction in young and very old Chinese adults: clinical characteristics and therapeutic implications

Characteristics and treatment analysis of young acute coronary syndrome patients in a tertiary care hospital: A cross-sectional retrospective study

Background and Aims

The prevalence of acute coronary syndrome (ACS) has been rising in the younger population worldwide. To fully comprehend the effects of the condition, it is crucial to examine the evolving characteristics and treatment options. The purpose of this study is to evaluate the characteristics and treatment analysis for young ACS patients in a tertiary care setting.

Methods

This cross-sectional, retrospective, single-center study included a random sample of patients who had been hospitalized for ACS over the period of a year. We collected and analyzed data on risk factors, diagnoses, angiographic patterns, and potential treatments.

Results

The study involved 198 young ACS patients in total. The majority of patients (57%) had no risk factors, and the majority of them (44%) had ST-elevation myocardial infarction (STEMI) as their diagnosis. The most common type (48%) was single-vessel disease (SVD). Statins and antiplatelet medications made up the majority of the patients' nonsurgical treatments (88% and 87%, respectively). A statistically significant difference exists between young and older ACS patients with gender (p < 0.01). However, it is not clinically relevant.

Conclusion

Men were the majority of young ACS patients, and STEMI, SVD were more prevalent. The majority of young ACS patients had no significant risk factors. To determine the risk factors of young ACS patients, a more thorough case-control study is critically needed.

Clinical features of myocardial infarction in young Japanese patients

Clinical features and outcomes of acute myocardial infarction (AMI) in the young have been poorly investigated. The aim of this study was to investigate the clinical features and hospital outcomes of AMI in young Japanese. We conducted a case-control study. A total of 53 consecutive AMI patients whose age was ≤ 45 years old were assigned to the young group and 106 AMI patients whose age was > 45 years old were assigned to the non-young group. We compared the clinical features and hospital outcomes between the two groups. Compared with the non-young group, the young group was associated with male sex, hyperlipidemia, current smoking, being overweight, single vessel disease, and Killip class I on admission. There were no differences in the length of hospital stay or major adverse cardiac events between the groups. However, mortality and ventricular rupture were slightly lower in the young. In conclusion, young AMI patients had clinical characteristics different to those of the non-young patients. Compared to non-young patients, modifiable risk factors such as smoking, hyperlipidemia, and being overweight were associated with young AMI patients.

Association of Interaction Between Smoking and CYP 2C19*3 Polymorphism With Coronary Artery Disease in a Uighur Population

Objectives: Cytochrome P450 (CYP) 2C19 is expressed in vascular endothelium and metabolizes arachidonic acid to biologically active epoxyeicosatrienoic acids (EETs), which are potent endogenous vasodilators and inhibitors of vascular inflammation. The purpose of this study is to explore the relationship between the interaction of CYP2C19*3 polymorphism and smoking and coronary artery disease (CAD) in a Uighur population. Methods: In a Chinese Uighur case-control study of patients with CAD (n = 336) and healthy controls (n = 370), we investigated the roles of polymorphism in the CYP2C19 gene by the use of polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis. Results: The CYP2C19*3 AG + AA genotype was significantly more prevalent in patients with CAD (6.25.0% vs 2.96%; P = .03). Multiple logistic regression analysis showed 4 independent risk factors: the interaction of CYP2C19*3 and smoking (OR 7.22, 95% confidence interval [CI] 2.32-10.23; P = .009), smoking (OR 3.23, 95% CI 1.72-5.44; P = .003), blood sugar (OR 2.12, 95% CI 1.03-4.21; P < .01), and hypertension (OR 1.74, 95% CI 0.98-2.34; P = .013). Conclusions: The CYP2C19*3 polymorphism and CAD were synergistically and significantly associated in Chinese Uighur patients.

Acute coronary syndromes in young patients: presentation, treatment and outcome

BACKGROUND

Acute coronary syndromes (ACS) in very young patients have been poorly described. We therefore evaluate ACS in patients aged 35 years and younger.

METHODS

In this prospective cohort study, 76 hospitals treating ACS in Switzerland enrolled 28,778 patients with ACS between January 1, 1997, and October 1, 2008. ACS definition included ST-segment elevation myocardial infarction (STEMI), non-ST-segment elevation myocardial infarction (NSTEMI), and unstable angina (UA).

RESULTS

195 patients (0.7%) were 35 years old or younger. Compared to patients>35 years, these patients were more likely to present with chest pain (91.6% vs. 83.7%; P=0.003) and less likely to have heart failure (Killip class II to IV in 5.2% vs. 23.0%; P<0.001). STEMI was more prevalent in younger than in older patients (73.1% vs. 58.3%; P<0.001). Smoking, family history of CAD, and/or dyslipidemia were important cardiovascular risk factors in young patients (prevalence 77.2%, 55.0%, and 44.0%). The prevalence of overweight among young patients with ACS was high (57.8%). Cocaine abuse was associated with ACS in some young patients. Compared to older patients, young patients were more likely to receive early percutaneous coronary interventions and had better outcome with fewer major adverse cardiac events.

CONCLUSIONS

Young patients with ACS differed from older patients in that the younger often presented with STEMI, received early aggressive treatment, and had favourable outcomes. Primary prevention of smoking, dyslipidemia and overweight should be more aggressively promoted in adolescence.

Synergistic effect of cytochrome P450 epoxygenase CYP2J2*7 polymorphism with smoking on the onset of premature myocardial infarction

OBJECTIVES

Cytochrome P450 (CYP) 2J2 is expressed in vascular endothelium and metabolizes arachidonic acid to biologically active epoxyeicosatrienoic acids (EETs), which are potent endogenous vasodilators and inhibitors of vascular inflammation. We aimed to elucidate the relationship between the functional CYP2J2*7 polymorphism and smoking for the onset of premature myocardial infarction (MI).

PATIENTS/METHODS

We studied 200 patients with acute MI onset under 45 years (84% men) and 200 sex- and age-matched controls. The polymorphism was determined using PCR and direct DNA sequencing analysis.

RESULTS

The CYP2J2*7 GT+TT genotype was significantly more prevalent in premature MI patients (32.0% versus 22.0%; p=0.02). Multiple logistic regression analysis showed four independent risk factors: the CYP2J2*7 T allele (OR 1.78, 95% confidence interval [CI] 1.1-6.4; p=0.02), smoking (OR 3.05, 95% CI 1.6-7.3; p<0.01), diabetes mellitus (OR 3.24, 95% CI 1.2-6.6; p<0.01), and hypertension (OR 1.95, 95% CI 1.1-5.7; p<0.01). Among non-smoking patients, the CYP2J2*7 T allele was associated with a 1.3-fold risk. However, smoking T-allele carriers had a significantly 6.7-fold higher risk (p=0.01 for interaction). This variant, but not wild type, significantly reduced promoter activity with nicotine in vitro. EET metabolites were significantly lower among CYP2J2*7 T allele carriers than the GG subjects (p<0.05). Smoking could further lower EET concentrations in T allele carriers than the non-smokers, especially in MI patients (3.3+/-1.0 ng/mL versus 6.8+/-1.3 ng/mL; p=0.001).

CONCLUSIONS

The CYP2J2*7 polymorphism and premature MI were synergistically and significantly associated in Taiwanese patients.

Stromelysin-1 promoter 5A/6A polymorphism is an independent genetic prognostic risk factor and interacts with smoking cessation after index premature myocardial infarction

OBJECTIVE

To evaluate the prognostic roles of multiple polymorphisms and smoking cessation for premature myocardial infarction (MI).

METHODS

We studied 170 patients with MI onset before the age of 45 years (range 27-45 years, 84% men) and analyzed the traditional risk factors and several candidate genes' associations with their subsequent coronary events.

RESULTS

Follow-up data were available for a total of 162 individuals (95.3%) with the other 38 individuals (4.7%) being lost-to-follow-up premature MI patients. During a mean period of 4.43 years' follow-up, diabetes mellitus (DM), hypertension, hypercholesterolemia and Killip's status > or =II were more frequent among patients with subsequent cardiac events (all P-values <0.05). The frequency of 5A allele of stromelysin-1 gene was significantly higher among event group (P = 0.01). Smoking cessation after MI, use of beta-blocker or angiotensin-converting enzyme inhibitor (ACEI) could improve outcome (all P-values <0.05). After multivariate analysis, we found that DM was an independent risk factor for survival [Hazard ratio (HR) 2.45, P = 0.01]. Successful smoking cessation and therapy with ACEI could have a protective effect (HR 0.33 and 0.09, P = 0.01 and <0.01, respectively). The stromelysin-1 5A gene polymorphism was also an independent survival predictor (HR 2.51, P = 0.03). In addition, smoking cessation could significantly modify the risk, especially among patients with 5A allele polymorphism (HR 6.75 vs. 1.50).

CONCLUSION

We thus conclude that the stromelysin-1 gene polymorphism alone or in combination with smoking cessation can influence the prognosis after index premature MI.

The 161TT genotype in the exon 6 of the peroxisome-proliferator-activated receptor γ gene is associated with premature acute myocardial infarction and increased lipid peroxidation in habitual heavy smokers

PPAR (peroxisome-proliferator-activated receptor) is a nuclear receptor. Activation of PPARγ by its ligands could modulate gene transcription, thereby leading to multiple anti-atherogenic and fibrinolytic effects. However, the association between the 161T allele in exon 6 of the PPARγ gene and premature AMI (acute myocardial infarction) is not clear. We recruited 146 patients with premature AMI (onset age ≤50 years) and 146 controls. The C161T polymorphism was examined using PCR and restriction-fragment-length polymorphism. Plasma levels of Ab-ox-LDL (antibody against oxidized low-density lipoprotein) were measured in 27 male smokers, whose genotypes have been identified. The frequency of the PPARγ TT genotype among patients with AMI was significantly higher than that in controls [13% compared with 5.5%; OR (95% CI) 2.7, (1.1–6.5), where OR and CI are odds ratio and confidence interval respectively]. This association was not observed in CC or CT genotypes. Using multivariate logistic regression analyses, we found that the homozygous TT genotype [OR (95% CI), 3.1 (1.2–7.9)], smoking [OR (95% CI), 3.5, (2.1–6.0)], hypertension [OR (95% CI), 3.6, (1.9–6.9)] and diabetes mellitus [OR (95% CI), 3.5 (1.5–8.4)] were independent risk factors for premature AMI. Plasma levels of Ab-ox-LDL were significantly higher in healthy volunteers with the TT genotype compared with those with the CC genotype (49.3±18.1 compared with 24.2±15.2 units/l respectively; P=0.02). Therefore in our study we observed an association between the PPARγ 161 TT genotype and premature AMI. Lipid peroxidation was significantly influenced by the 161T allele.

Long-term prognosis of patients having acute myocardial infarction when </=40 years of age

Data on the long-term prognosis of acute myocardial infarction (AMI) in young patients are limited. This study investigated long-term survival and risk predictors in a series of 108 consecutive patients </=40 years old who represented 4% of 2,644 patients who presented with AMI at a single center between June 1986 and April 1992. Four patients died soon after admission. The overall mortality rate of the 104 survivors was 25.5% at 15 years. The mortality rate was higher in patients who had type 1 diabetes mellitus (p = 0.01), long-term excessive alcohol intake (p = 0.035), peripheral arterial disease (p = 0.004), previous AMI (p = 0.04), anterior AMI (p = 0.01), and depressed left ventricular ejection fraction (p <0.0001). Cumulative survival rates (Kaplan-Meier analysis) at 1, 5, 10, and 15 years were 99%, 95%, 86%, and 75%, respectively. Event-free survival rates (death, AMI, coronary intervention, severe angina pectoris, malignant arrhythmias, and congestive heart failure) at the same times were 88%, 76%, 60%, and 43%, respectively. The strongest independent predictors of the long-term mortality rate were ejection fraction </=45% (odds ratio 4.4, 95% confidence interval 1.6 to 12.4, p <0.001) and peripheral arterial disease (odds ratio 45.9, 95% confidence interval 3.79 to 555, p <0.0001). These data suggest that the long-term prognosis and functional status of young patients who have AMI are not benign, especially when ejection fraction is decreased or peripheral atherosclerotic disease is present.

Acute myocardial infarction in the young--The University of Michigan experience

BACKGROUND

The purpose of this study was to assess frequency, risk factors, treatment, and complications of very young patients with acute myocardial infarction (MI) at the University of Michigan Medical Center (UMMC).

METHODS

From a database of 976 consecutive patients admitted to the UMMC with acute MI between 1995 and 1998, we compared care and outcomes of patients divided into 3 age categories: <46 years, 46-54 years, and >54 years. Risk factors, presenting symptoms, type of MI, management, complications, and hospital outcomes of the 3 groups were evaluated.

RESULTS

Young patients represented >10% of all patients with acute MI, and >25% of these individuals were women, a number considerably higher than seen in previous studies. This group of young patients was more likely to have Q-wave MI and risk factors such as family history and tobacco use and less likely to have a history of angina. Although all 3 groups received similar inpatient treatment, there was more attention paid to risk factor modification such as smoking cessation and referral to cardiac rehabilitation in younger individuals. Young patients had fewer in-hospital complications and a lower mortality rate.

CONCLUSIONS

At the University of Michigan, >1 in 10 with acute MI is <46 years old. Data suggest that current management and aggressive risk factor modification are quite good in this particular group, and overall the mortality rate is very low.

Complications of acute myocardial infarction in patients > or = 90 years of age

Forty consecutive 90-year-old persons with an acute myocardial infarction were studied to describe the noncardiac complications of their care. Common negative consequences of hospitalization of these patients included delirium, pressure ulcers, and poor ambulatory status at discharge.

Normal angiogram after myocardial infarction in young patients: a prospective clinical-angiographic and long-term follow-up study

This is an observational study in which we compared the clinical characteristics and the long-term course of young patients having acute myocardial infarction and angiographically normal coronary arteries and young patients showing significant coronary artery disease. In 87 patients aged < or = 40 years who suffered an acute myocardial infarction, enrolled in a prospective study over a period of 6.5 years, coronary anatomy was determined by angiography within a month of admission. The risk factors, clinical data, ventricular function and the long-term outcome were compared between patients with normal angiograms (Group 1, n = 12) and patients with coronary artery disease (Group 2, n = 75). Patients in Group 1 had a lower number of risk factors associated with them (17% vs. 64% with > 1 risk factor, P < 0.005), were younger (32 +/- 5 vs. 36 +/- 4, P < 0.01), lighter smokers (25% vs. 55% for > or = 2 packs per day, P < 0.05), had less frequent hypertension (0 vs. 25%, P < 0.05), hypercholesterolemia (17% vs. 52%, P = 0.02) and had a lower mean total cholesterol level (201 +/- 42 vs. 245 +/- 60 mg/100 ml, P < 0.05) than patients in Group 2. They also had a more common onset of their infarction during heavy physical exertion (67% vs. 17%, P < 0.001). A history of previous myocardial infarction, infarct location, global left ventricular function and regional wall motion were similar in both groups. After a mean follow-up period of 41 +/- 23 months, no patient died or had a second myocardial infarction in Group 1, and 4 patients had died in Group 2. The appearance of angina, less frequent in Group 1 than Group 2, tended to correlate with the extension of the coronary artery disease. We concluded that young patients with myocardial infarction have good prognosis irrespective of the coronary anatomy, although patients with normal coronary angiograms had less risk factors and less frequent new ischaemic events.

Myocardial infarction in men aged 40 years or less: a prospective clinical-angiographic study

HYPOTHESIS

The study was undertaken to characterize acute myocardial infarction (AMI) in young patients.

METHODS

In all 108 consecutive Mediterranean patients with AMI (102 men and 6 women), aged < or = 40 years, were prospectively included in this study over a period of 6.5 years. Coronary angiography was carried out within the first month and data from these patients with normal or diseased coronary arteries were compared. Clinical features, risk factors, and in-hospital and late morbidity and mortality were evaluated.

RESULTS

Young patients with AMI represent 4.1% of the 2,644 patients admitted because of definite AMI during this period. The most common risk factors were cigarette smoking (94.5%) and hypercholesterolemia (48%). Location of the AMI was anterior in 37%, inferior in 57.5%, and non-Q in 5.5%. A history of previous angina was present in 42.5% of the patients, including all seven patients with previous myocardial infarction (6.5%). However, in 52% of the patients the anginal episodes started in the week prior to the AMI. In-hospital mortality and mortality during a mean follow-up of 41 +/- 23 months were 3.7 and 3.8%, respectively. The Kaplan-Meier actuarial curve assessed on 97 of 104 survivors was 100 and 94% at 1 and 5 years, respectively. Coronary arteries were angiographically normal in 17 (20%) of 87 survivors. Compared with young patients who had obstructive lesions, this subset had a lower age and fewer risk factors, reinfarction (p < 0.05), and late angina (p < 0.01), but development of congestive heart failure and survival were similar in both groups.

CONCLUSION

These data suggest that young patients with AMI are very frequently heavy smokers, have a high incidence of angiographically normal coronary arteries, and that the short- and long-term prognosis is excellent.