Acute myocardial infarction: Clinical features and outcomes in young adults in Singapore

Clinical Presentation and In-Hospital Outcomes of Acute Myocardial Infarction in Young Patients: Japanese Nationwide Registry

Background

Acute myocardial infarction (AMI) in young patients is a concerning issue because of its adverse health and social impacts. Nevertheless, risk factors and prognosis of AMI in young patients are yet to be characterized.

Objectives

This study aimed to characterize AMI in young patients who underwent primary percutaneous coronary intervention (PCI) using large-scale nationwide all-comer registry data in Japan, the Japanese Percutaneous Coronary Intervention (J-PCI).

Methods

This retrospective cohort study evaluated the J-PCI registry data of patients with AMI aged 20 to 79 years who underwent primary PCI between January 2014 and December 2018. Data on risk factor profiles, clinical features, post-procedural complications, and in-hospital outcomes were reviewed.

Results

Among 213,297 patients with AMI who underwent primary PCI, 23,985 (11.2%) were young (ages 20 to 49 years). Compared with the older group (ages 50 to 79 years; n = 189,312), the younger group included a higher number of men, smokers, patients with dyslipidemia, and patients with single-vessel disease, and a lower number of patients with hypertension and diabetes. Despite favorable clinical profiles, younger age was associated with a higher rate of presentation with cardiopulmonary arrest (CPA). Further, concomitant CPA was strongly associated with in-hospital mortality in young patients (odds ratio: 14.2; 95% CI: 9.2 - 21.9).

Conclusions

Younger patients with AMI presented a higher risk of CPA, which was strongly associated with in-hospital mortality. The results of this study highlight the importance of primary AMI prevention strategies in young individuals.

Causes, Angiographic Characteristics, and Management of Premature Myocardial Infarction: JACC State-of-the-Art Review

Among patients presenting with acute myocardial infarction (AMI), the proportion of young individuals has increased in recent years. Although coronary atherosclerosis is less extensive in young patients with AMI, with higher prevalence of single-vessel disease and rare left main involvement, the long-term prognosis is not benign. Young patients with AMI with obstructive coronary artery disease have similar risk factors as older patients except for higher prevalence of smoking, lipid disorders, and family history of premature coronary artery disease, and lower prevalence of diabetes mellitus and hypertension. Smoking cessation is by far the most effective secondary preventive measure. Myocardial infarction with nonobstructive coronary arteries is a relatively common clinical entity (10%-20%) among young patients with AMI, with intravascular and cardiac magnetic resonance imaging being key for diagnosis and potentially treatment. Spontaneous coronary artery dissection is a frequent pathogenetic mechanism of AMI among young women, requiring a high degree of suspicion, especially in the peripartum period.

Prognostic Outcomes in Acute Myocardial Infarction Patients Without Standard Modifiable Risk Factors: A Multiethnic Study of 8,680 Asian Patients

Background

An increasing proportion of patients with acute myocardial infarction (AMI) are presenting without standard modifiable risk factors (SMuRFs) of hypertension, hypercholesterolemia, diabetes, and smoking, but with an unexpectedly increased mortality. This study examined the SMuRF-less patients presenting with AMI in a multiethnic Asian population.

Methods

We recruited patients presenting with AMI from 2011 to 2021 and compared the prevalence, clinical characteristics, and outcomes of SMuRF-less and SMuRF patients. Multivariable analysis was used to compare the outcomes of 30-day cardiovascular mortality, all-cause mortality, readmission, cardiogenic shock, stroke, and heart failure. Kaplan-Meier curves were constructed for 30-day cardiovascular mortality, with stratification by ethnicity, gender and AMI type, and 10-year all-cause mortality.

Results

Standard modifiable risk factor-less patients, who made up 8.6% of 8,680 patients, were significantly younger with fewer comorbidities that include stroke and chronic kidney disease, but higher rates of ventricular arrhythmias and inotropic or invasive ventilation requirement. Multivariable analysis showed higher rates of cardiovascular mortality (HR 1.48, 95% CI: 1.09-1.86, p = 0.048), cardiogenic shock (RR: 1.31, 95% CI: 1.09-1.52, p = 0.015), and stroke (RR: 2.51, 95% CI: 1.67-3.34, p = 0.030) among SMuRF-less patients. A 30-day cardiovascular mortality was raised in the SMuRF-less group, with similar trends in men, patients with ST-segment elevation myocardial infarction (STEMI), and the three Asian ethnicities. All-cause mortality remains increased in the SMuRF-less group for up to 5 years.

Conclusion

There is a significant proportion of patients with AMI without standard risk factors in Asia, who have worse short-term mortality. This calls for greater focus on the management of this unexpectedly high-risk subgroup of patients.

Comparison of Mortality Outcomes in Acute Myocardial Infarction Patients With or Without Standard Modifiable Cardiovascular Risk Factors

Background

Acute myocardial infarction (AMI) cases have decreased in part due to the advent of targeted therapies for standard modifiable cardiovascular disease risk factors (SMuRF). Recent studies have reported that ST-elevation myocardial infarction (STEMI) patients without SMuRF (termed “SMuRF-less”) may be increasing in prevalence and have worse outcomes than “SMuRF-positive” patients. As these studies have been limited to STEMI and comprised mainly Caucasian cohorts, we investigated the changes in the prevalence and mortality of both SMuRF-less STEMI and non-STEMI (NSTEMI) patients in a multiethnic Asian population.

Methods

We evaluated 23,922 STEMI and 62,631 NSTEMI patients from a national multiethnic registry. Short-term cardiovascular and all-cause mortalities in SMuRF-less patients were compared to SMuRF-positive patients.

Results

The proportions of SMuRF-less STEMI but not of NSTEMI have increased over the years. In hospitals, all-cause and cardiovascular mortality and 1-year cardiovascular mortality were significantly higher in SMuRF-less STEMI after adjustment for age, creatinine, and hemoglobin. However, this difference did not remain after adjusting for anterior infarction, cardiopulmonary resuscitation (CPR), and Killip class. There were no differences in mortality in SMuRF-less NSTEMI. In contrast to Chinese and Malay patients, SMuRF-less patients of South Asian descent had a two-fold higher risk of in-hospital all-cause mortality even after adjusting for features of increased disease severity.

Conclusion

SMuRF-less patients had an increased risk of mortality with STEMI, suggesting that there may be unidentified nonstandard risk factors predisposing SMuRF-less patients to a worse prognosis. This group of patients may benefit from more intensive secondary prevention strategies to improve clinical outcomes.

Low high density lipoprotein cholesterol levels and acute coronary syndrome in young patients admitted at a tertiary care facility

BACKGROUND

Coronary artery disease (CAD) is a cardiovascular disease which is related to mortality and morbidity among the Indians predominantly in the older age group. But, recently CAD has been found more often in young population. Hence, our study aims to observe the outcomes based on various categories of high density lipoprotein (HDL) cholesterol levels estimated during admission at the hospital and correlate the levels of HDL cholesterol with severity of CAD as measured by Gensini score.

METHODS

A cross-sectional study was conducted in 151 young patients (18-45 years) who were admitted at the hospital with newly diagnosed acute coronary syndrome (ACS). Tests such as electrocardiogram, cardiac enzyme assay, hematologic and biochemical tests including fasting lipid profile levels were taken into account.

RESULTS

There was an inverse relation observed between the number of vessels involvedand HDL cholesterol levels. Those with lower levels of HDL cholesterol were more vulnerable to multi-vessel CAD. However, no association was observed between HDL cholesterol and severity of CAD as measured by Gensini score.

CONCLUSION

In young patients with acute coronary syndrome and diminished HDL cholesterol levels had a greater number of vessels involved when compared with elevated HDL cholesterol levels group. However, low HDL cholesterol levels had no association with severity of CAD as measured by Gensini score. No statistically significant association was noticed between levels of HDL cholesterol and in hospital mortality /morbidity.

Clinical Characteristics, Prognosis, and Gender Disparities in Young Patients With Acute Myocardial Infarction

Background: Young people hold a stable or increasing percentage of patients with acute myocardial infarction (AMI) in many countries. However, data on clinical characteristics and outcomes of young AMI patients were insufficient. This study aimed to analyze clinical characteristics, prognosis, and gender disparities in patients aged ≤45 years with AMI. Methods: A total of 24,125 patients from China Acute Myocardial Infarction registry were included in this study. Clinical characteristics, managements, and in-hospital and 2-year outcomes were compared between patients aged ≤45 years and those aged >45 years. Predictors of all-cause death were obtained using multivariate regression models. Gender disparities of AMI were analyzed among young patients. Results: Of 24,125 patients, 2,042 (8.5%, 116 female) were aged ≤45 years. Compared with patients aged >45 years, young patients were more often male, current smokers, and more likely to have medical history of hyperlipidemia. Smoking (72.1%) was the major modifiable risk factor in patients aged ≤45 years. Young patients received more evidence-based medications and had significantly lower risk of both in-hospital and 2-year adverse events than older patients. Education level and left ventricular ejection fraction were independent predictors of 2-year mortality in young patients. Moreover, symptom onset to admission time of young women was significantly longer than that of young men. Young women were less likely to receive percutaneous coronary intervention and suffered higher risk of in-hospital adverse events than young men (adjusted odds ratio for death: 5.767, 95% confidence interval 1.580-21.049, p = 0.0080; adjusted odds ratio for the composite of death, re-infarction, and stroke: 3.981, 95% confidence interval 1.150-13.784, p = 0.0292). Young women who survived at discharge had a higher 2-year cumulative incidence of death (3.8 vs 1.4%, p log-rank = 0.0412). Conclusions: Patients aged ≤45 years constituted a non-negligible proportion of AMI patients, with higher prevalence of smoking and hyperlipidemia but better care and prognosis compared with older patients. There were significant gender disparities of managements and outcomes in young patients. More efforts to improve quality of care in young women are needed.

Clinical Characteristics and Prognosis of Young Middle Eastern Adults with ST-Elevation Myocardial Infarction: One-Year Follow-Up

AIMS

Few studies have investigated premature ST-elevation myocardial infarction (STEMI) in the Middle East. We aimed to compare the clinical characteristics and one-year prognosis of young (<45 years) and older (≥45 years) Middle Eastern adults with STEMI.

METHODS AND MATERIAL

A total of 706 patients with STEMI, who were prospectively enrolled in the First Jordanian Percutaneous Coronary Intervention Registry, were stratified into two groups (<45 or ≥45 years). Baseline clinical variables and one-year major adverse cardiovascular events (MACE) were evaluated.

RESULTS

Young patients (<45 years) comprised 17.4% of STEMI patients (123 of 706). Compared with older patients (≥45 years), young patients were mostly male (96% vs 82%, P<0.001), smokers (86% vs 49%, P<0.001) and less likely to have multi-vessel disease (26% vs 44%, P=0.001). Anterior STEMI was the most common diagnosis and left anterior descending artery was the most common culprit vessel in both groups. There were no significant differences between the younger and older patients in in-hospital (20% vs 19%, P=0.12) and one-year MACE (24% vs 26%, P=0.68). However, none (0%) of the young died during one-year follow-up while 21 (4%) of the older patients died (P=0.036).

CONCLUSIONS

Young adult patients in the Middle East with STEMI are more likely to be smoking men with multiple risk factors and single vessel disease by angiography. Although, younger patients had similar one-year MACE to older patients, their mortality rate appears to be better. A larger study is warranted to investigate this vulnerable group of patients to prevent future events.

Association between age and infection in patients with acute ST-elevation myocardial infarction

Background

ST-elevation myocardial infarction (STEMI) in young patients has a unique risk profile. We aimed to detect bacteria in aspirate of infarct artery in young versus old patients.

Results

Aspirates of consecutive 140 patients who underwent a primary coronary intervention were taken for bacteriological, microscopical, and immunohistochemical (for bacterial pneumolysin) examinations. Their results were calculated in young (≤ 50 years) versus old (> 50 years) patients. Median age (interquartile range) was 45 (38–48) years in young (60 patients) and 59 (55–65) years in old (80 patients) patients, p < 0.0001. Both groups had similar baseline data except age, males, diabetes, hyperlipidemia, family history, lesion length, and ectatic vessel. Different bacteria were cultured in 11.3% of all patients involving 22.6% of young and 2.8% of old patients [hazard ratio 8.03 (95% CI 1.83–51.49), p = 0.002]. By multivariate analyses, age groups and leukocytic count were independent predictors of infection (bacteria and pneumolysin), p = 0.027 and p < 0.0001, respectively. Optimal cutoff value of leukocytic count was 12,250 cells/μl [ROC curve sensitivity 85.7%, specificity 86.4%, and AUC 0.97 (95% CI 0.95–1.0), p < 0.001]. Infection was an independent predictor of STEMI in young versus old patients, p < 0.001. Nevertheless, in-hospital events occurred insignificantly different and neither age groups nor infection was predictor of in-hospital events.

Conclusions

Young patients had significantly higher percentage of bacteria in their infarcted artery than old patients. High leukocytic count in patients below 50 predicts infection that causes acute myocardial infarction. Antibacterial trials directed toward this group are required for secondary prevention.

Characteristics and outcomes of young patients with ST segment elevation myocardial infarction undergoing primary percutaneous coronary intervention: retrospective analysis in a multiethnic Asian population

OBJECTIVE

ST segment elevation myocardial infarction (STEMI) is associated with significant mortality leading to loss of productive life years, especially in younger patients. This study aims to compare the characteristics and outcomes of young versus older patients with STEMI undergoing primary percutaneous coronary intervention (PPCI) to help focus public health efforts in STEMI prevention.

METHODS

Data from the Coronary Care Unit database of the National University Hospital, Singapore from July 2015 to June 2019 were reviewed. Patients were divided into young (<50 years old) or older (≥50 years old) groups.

RESULTS

Of the 1818 consecutive patients with STEMI who underwent PPCI, 465 (25.6%) were <50 years old. Young compared with older patients were more likely to be male, current smokers, of Indian ethnicity, have family history of ischaemic heart disease (IHD) and had lower 1 year mortality (3.4% vs 10.4%, p<0.0001). Although diabetes, hypertension or dyslipidaemia was less common among young patients, the prevalence of having any one of these risk factors was high in the range of 28% to 38%. Age was an independent predictor of mortality in the older but not younger patients with STEMI, and diabetes showed a trend towards mortality in both groups.

CONCLUSION

Young patients with STEMI are more often smokers, of Indian ethnicity and had family history of IHD, although cardiometabolic risk factors are also prevalent. Mortality is lower, but not negligible, among the young patients with STEMI. Public health efforts are needed to reduce the prevalence of these risk factors among the constitutionally susceptible population.

Acute heart failure – The ‘real’ Malaysian experience: An observational study from a single non-cardiac centre

Background:

Cardiovascular care in Malaysia adopts a ‘spoke-and-hub’ model, leaving the majority of acute heart failure (AHF) care to non-cardiac centres. Granular data on AHF care are essential and yet remain scarce.

Objectives:

This study aimed to illustrate the baseline characteristics, management and outcome of AHF patients.

Methods:

A retrospective, cross-sectional study was conducted on 1307 AHF patients admitted between 1 January 2012 and 31 December 2016.

Results:

The younger and Malay-predominant population reflects the distribution of ischaemic heart disease in Malaysia, highlighting the need to tackle metabolic risks factors. The majority are precipitated by ischaemia (61.8%). Common co-morbidities include hypertension (70.9%), coronary artery disease (57.8%) and diabetes (62.2%). The majority were of New York Heart Association Class II (31.9%) and Class III (25.6%). A total of 14.5% required inotropes and vasopressors, 12.9% required intravenous nitrates and 8.6% required dialysis. A further 4.9% of patients required intubation and mechanical ventilation, and 25.9% required non-invasive ventilation. Readmission and mortality were extremely high in our population. Short inpatient stays, restricting optimisation of medication, and gaps in the provision of coronary intervention and stress testing are possible contributing factors. When compared to global and regional registries, disparities were noted specifically surrounding mortality rate and optimum use of guideline-directed medical therapy.

Conclusion:

Although smaller and single centred, our study provides a unique insight into a pure Malaysian-only cohort from a hospital with no cardiology services in-house, which is more reflective of the majority of hospitals in Malaysia, unlike previous studies and registries.

Cross-Sectional Study of Ethnicity and Chronic Heart Failure: Complex Interplay of Health and Wealth

Objectives: Extrapolating data from international and regional registries on chronic heart failure provides a challenge in Malaysia in view of it being a multicultural country. This study aimed to illustrate the chronic heart failure landscape within northern Kuala Lumpur and identify differences amongst major ethnic groups. Methods: A retrospective, single-centre study was conducted between the 1st January 2013 and 30th April 2016. Patients with left ventricular ejection fraction ≤45% were identified and information was collected on these individuals’ demographics, risk factors, and aetiology. Comparisons were made between three major ethnic groups within Malaysia, and between the author’s database and that of other international registries. Results: 1,181 patients were identified, the majority being Malays (67.3%) and male (81.2%). The mean age was 58.2±11.7 years. The majority had ischaemic risk factors, including previous and current smoking habits (56.7%), coronary artery disease (66.1%), hypertension (71.2%), diabetes (61.8%), and dyslipidaemia (47.9%). There were significant differences noted when looking at rates of dyslipidaemia, diabetes, atrial fibrillation, and chronic kidney disease amongst different ethnicities. The mean left ventricular ejection fraction in Malays was lower (33.1±9.6%) compared to that of Chinese (34.7±8.7%) and Indians (34.9±8.3%). There was marked differences seen in this study’s cohort, compared to three major Asian registries: The 2003 Chong et al. registry, Inter-CHF, and ASIAN-HF. Conclusion: There exists great disparity in chronic heart failure burden amongst populations, and therefore local registries are needed to narrow the gap in knowledge regarding chronic heart failure within Malaysia.

Identification of Haptoglobin as a Potential Biomarker in Young Adults with Acute Myocardial Infarction by Proteomic Analysis

Background

Acute myocardial infarction (AMI) molecular research in young adults is still limited. The aim of this study is to identify AMI proteomic biomarker(s) in young adults.

Methods

This study comprised of two phases namely discovery and verification. In the discovery phase, proteins in the pooled plasma samples from young male adults between 18 and 45 years (10 AMI patients and 10 controls) were separated using two-dimensional electrophoresis. The protein spots that were expressed differently in the AMI patients were identified via matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. The plasma concentrations of these proteins were quantified using enzyme-linked immunosorbent assay during the verification phase (40 AMI patients and 80 controls).

Results

Haptoglobin (Hp), apolipoprotein AI (Apo AI) and apolipoprotein AIV (Apo AIV) were up-regulated in the discovery phase. In the verification phase, the plasma concentration of Hp was significantly higher in AMI patients than the controls (P < 0.001). Logistic regression showed an association between Hp and AMI in young adults (odds ratio [OR] = 1.016, 95% CI: 1.002–1.030, P = 0.025) independent of other AMI risk factors. Hp was significantly correlated with high sensitivity C-reactive protein (hs-CRP) (r = 0.424, P < 0.001).

Conclusion

In young adults with AMI, plasma Hp concentrations were elevated and it is independently associated with AMI. A positive correlation with hs-CRP suggests Hp could be a potential biomarker of AMI in young adults.

Diagnosis of myocardial infarction with nonobstructive coronary arteries in a young man in the setting of acute myocardial infarction after endoscopic retrograde cholangiopancreatography: A case report

BACKGROUND

Acute myocardial infarction (AMI) is characterized by chest pain as well as cardiac troponin I (cTnI) and electrocardiography (ECG) changes. Recently, clinical researchers have used the term “MINOCA” to indicate myocardial infarction with nonobstructive coronary arteries. To the best of our knowledge, no report has documented MINOCA in a young patient after choledocholithiasis by endoscopic retrograde cholangiopancreatography (ERCP).

CASE SUMMARY

An 18-year-old Chinese man presented to the cardiac intensive care unit with chest pain radiating to the left shoulder for 1 h after choledocholithiasis by ERCP and the following treatment. ECG showed a sinus rhythm with ST-segment elevation in the II, III, and aVF leads compared with the baseline. Laboratory data revealed cTnI levels of 67.55 ng/mL and 80 ng/mL at the peak (relative index below 0.034 ng/mL) and creatine kinase-MB levels of 56 U/L and 543 U/L at the peak (relative index below 24 U/L). AMI was suspected, and coronary angiography was performed the second day. The results revealed a smooth angiographic appearance of all arteries. The patient had been diagnosed with gallstones and cholecystitis for four years but had not accepted treatment. He had abdominal pain and bloating a week previously and underwent ERCP and subsequent treatments on the second day of admission; 1.4 cm × 1.6 cm of stones were removed from his common bile duct during surgery. The results of his laboratory tests at admission revealed abnormal alanine aminotransferase, aspartate aminotransferase, glutamyl transpeptidase, total bile acid, total bilirubin, direct bilirubin, and indirect bilirubin levels. His temperature, heart rate, blood pressure, and body mass index were normal. His echocardiographic examination revealed no obvious abnormalities in the structure and movement of the ventricular wall and an estimated left ventricular ejection fraction of 57% after the heart attack. His cholesterol and triglycerides were within normal ranges, and his low-density lipoprotein cholesterol was 2.23 mmol/L (normal range 2.03-3.34 mmol). Further testing after AMI revealed nothing remarkable in his erythrocyte sedimentation rate, thyroid function, and tumour markers.

CONCLUSION

We ultimately made a diagnosis of MINOCA caused by coronary artery spasm, which seemed to be the most suitable diagnosis of this young patient. We are concerned that the heart attack may have been induced by the ERCP rather than occurred coincidentally afterward, so we should investigate the timing of the event further. Additional studies are needed to unravel the underlying pathophysiology.

Lipoprotein(a): An underrecognized genetic risk factor for malignant coronary artery disease in young Indians

Malignant coronary artery disease (CAD) refers to a severe and extensive atherosclerotic process involving multiple coronary arteries in young individuals (aged <45 years in men and <50 years in women) with a low or no burden of established risk factors. Indians, in general, develop acute myocardial infarction (AMI) about 10 years earlier; AMI rates are threefold to fivefold higher in young Indians than in other populations. Although established CAD risk factors have a predictive value, they do not fully account for the excessive burden of CAD in young Indians. Lipoprotein(a) (Lp(a)) is increasingly recognized as the strongest known genetic risk factor for premature CAD, with high levels observed in Indians with malignant CAD. High Lp(a) levels confer a twofold to threefold risk of CAD-a risk similar to that of established risk factors, including diabetes. South Asians have the second highest Lp(a) levels and the highest risk of AMI from the elevated levels, more than double the risk observed in people of European descent. Approximately 25% of Indians and other South Asians have elevated Lp(a) levels (≥50 mg/dl), rendering Lp(a) a risk factor of great importance, similar to or surpassing diabetes. Lp(a) measurement is ready for clinical use and should be an essential part of all CAD research in Indians.

Effect of factor XIII levels and polymorphisms on the risk of myocardial infarction in young patients

Factor XIII (FXIII) stabilizes and protects the fibrin network. Its role in myocardial infarction (MI) is still to be clarified. To evaluate the association of FXIII levels with MI in young patients and to investigate how the FXIII-A p.Val34Leu, FXIII-B p.His95Arg, and IVS11, c.1952 + 144 C>G (Intron K) polymorphisms influence FXIII levels and MI risk. Patients with ST elevation MI below 40 years of age (MI, n = 119), age-matched clinical controls (CC, n = 101) without MI and coronary artery disease, and healthy controls (HC, n = 120) were investigated for FXIII activity, FXIII-A₂B₂, FXIII-B concentrations and for the polymorphisms. FXIII activity and FXIII-A₂B₂ antigen were significantly elevated in MI. FXIII activity and antigen were significantly elevated in Arg95, while decreased in Intron K "G" carriers. Smoking had an independent increasing effect on FXIII activity and FXIII-A₂B₂ antigen. Intron K C>G polymorphism significantly decreased the risk of MI in patients with elevated fibrinogen. Among the investigated factors Intron K C>G polymorphism and smoking have the most powerful effect on FXIII levels and on the risk of MI in the young. The effect of smoking on coronary thrombus formation may partially be attributed to its FXIII increasing effect.

Impact of hepatitis C virus infection on long-term mortality after acute myocardial infarction: a nationwide population-based, propensity-matched cohort study in Taiwan

INTRODUCTION

The influence of hepatitis C virus (HCV) infection on long-term outcomes of patients with acute myocardial infarction (AMI) is unclear. Therefore, this study aimed to analyse the impact of HCV infection on 12-year mortality rates after AMI using data from the Taiwan National Health Insurance Research Database (NHIRD).

METHODS

NHIRD data for approximately 23 000 000 patients between January 2000 and December 2012 were analysed. A total of 186 112 cases of first AMI admission were identified. A total of 4659 patients with HCV infection not receiving interferon therapy were enrolled and divided into those with (n=107) or without (n=4552) cirrhosis. Using one-to-one matching, 4552 matched controls were included in the final analysis.

RESULTS

The 12-year mortality rate was significantly higher in patients with AMI with HCV infection and cirrhosis than in those with HCV infection but without cirrhosis (P<0.0001) or controls (P<0.0001). Patients with HCV infection but without cirrhosis had significantly higher long-term mortality rates than the matched controls (P<0.0001). The HR for mortality was higher in patients with HCV infection (HR 1.12; 95% CI 1.06 to 1.18). HCV influenced outcomes among the subgroups of patients who were male (HR 1.15) and those who had hypertension (HR 1.14).

CONCLUSIONS

HCV infection influenced the 12-year mortality rates of patients with AMI, especially those who were male and those who had hypertension. Cirrhosis further increased the long-term mortality rates of patients with AMI with HCV infection.

Association of elevated triglycerides and acute myocardial infarction in young Hispanics

BACKGROUND

Previous studies have demonstrated that acute myocardial infarction (AMI) in young patients (age <45years) is associated with a high prevalence of smoking, obesity, hyperlipidemia and single vessel coronary artery disease (CAD). Hispanics represent the largest growing ethnic minority in the United States, yet features of AMI in young Hispanics have not been described.

METHODS

Patients undergoing percutaneous coronary intervention for AMI at Los Angeles County + University of Southern California Medical Center and Keck Medical Center were studied. We compared young Hispanics (age<45, n=47) with older patients (Hispanics and non-Hispanics age ≥45, n=888) to identify unique features of AMI in young Hispanics. We also compared young Hispanics with young non-Hispanics (n=33) and older Hispanics (n=447) in regards to traditional CAD risk factors, laboratory values and in-hospital outcomes. Multivariable logistic regression was performed to identify variables independently associated with in-hospital mortality.

RESULTS

Young Hispanics had higher triglyceride levels than young non-Hispanics and older patients (234.5±221.0mg/dL vs. 145.3±67.4mg/dL vs. 156±118.2mg/dL, p<0.0004); and higher triglyceride than older Hispanics (234.5±221.0 vs. 147.0±98.9mg/dL, p<0.02). Body mass index was independently associated with the logarithm (base10) of triglyceride levels (p<0.0001). Hispanic ethnicity and age<45years, however, were not independently associated with in-hospital mortality.

CONCLUSIONS

Young Hispanics with AMI have higher triglyceride levels than young non-Hispanics and older Hispanics. The elevated triglyceride levels may be related to lifestyle changes experienced by a young immigrant population transitioning to life in the United States.

Receptor Activity-modifying Proteins 2 and 3 Generate Adrenomedullin Receptor Subtypes with Distinct Molecular Properties

Adrenomedullin (AM) is a peptide hormone with numerous effects in the vascular systems. AM signals through the AM1 and AM2 receptors formed by the obligate heterodimerization of a G protein-coupled receptor, the calcitonin receptor-like receptor (CLR), and receptor activity-modifying proteins 2 and 3 (RAMP2 and RAMP3), respectively. These different CLR-RAMP interactions yield discrete receptor pharmacology and physiological effects. The effective design of therapeutics that target the individual AM receptors is dependent on understanding the molecular details of the effects of RAMPs on CLR. To understand the role of RAMP2 and -3 on the activation and conformation of the CLR subunit of AM receptors, we mutated 68 individual amino acids in the juxtamembrane region of CLR, a key region for activation of AM receptors, and determined the effects on cAMP signaling. Sixteen CLR mutations had differential effects between the AM1 and AM2 receptors. Accompanying this, independent molecular modeling of the full-length AM-bound AM1 and AM2 receptors predicted differences in the binding pocket and differences in the electrostatic potential of the two AM receptors. Druggability analysis indicated unique features that could be used to develop selective small molecule ligands for each receptor. The interaction of RAMP2 or RAMP3 with CLR induces conformational variation in the juxtamembrane region, yielding distinct binding pockets, probably via an allosteric mechanism. These subtype-specific differences have implications for the design of therapeutics aimed at specific AM receptors and for understanding the mechanisms by which accessory proteins affect G protein-coupled receptor function.

Predictors of Health-Related Quality of Life Among Patients With Myocardial Infarction

This cross-sectional correlational study aimed to examine health-related quality of life (HRQoL) and its predictors among patients with myocardial infarction (MI). One hundred and twenty-eight outpatients with MI were recruited from a university hospital. The 12-item Short-Form Health Survey version 2, Myocardial Infarction Dimensional Assessment Scale (MIDAS), and Hospital Anxiety and Depression Scale (HADS) were used to measure the study variables. Compared with the findings of similar studies of patients with MI, this sample, despite having significant coronary risk factors, reported generally better HRQoL. Predictors of physical HRQoL included low monthly household income, whereas predictors of mental HRQoL included ex-smoker, alcohol use, hypertension, anxiety, and depression. Special attention may need to be given to those people with a low income level, who are ex-smokers, use alcohol, or have hypertension, anxiety, or depression.

Health-related quality of life and its predictors among outpatients with coronary heart disease in Singapore

AIMS AND BACKGROUND

Coronary heart disease (CHD) is a major cause of death and disability and negatively impacts on patients' health-related quality of life (HRQoL). This study aimed to explore HRQoL and identify its predictors among outpatients with CHD in Singapore.

METHODS

A correlational study was conducted with a convenience sample of 106 outpatients with CHD recruited from a public hospital. HRQoL outcomes were measured using the Short Form-12 Health Survey (SF-12), Medical Outcomes Study Social Support Survey (MOS-SSS) and Hospital Anxiety and Depression Scale (HADS).

RESULTS

Patients reported a generally high level of HRQoL as assessed by SF-12. Those aged over 65years reported significantly higher mental health and those who were married had higher levels of education or income reported significantly higher physical health. There were significant negative correlations between physical and mental health and anxiety and depression (p<.05). Perceived social support was negatively correlated with anxiety and depression and positively correlated with mental health. Education level and depression significantly predicted physical health, while age, anxiety and depression predicted mental health.

CONCLUSION

Anxiety, depression, age and education are significant predictors of HRQoL in this patient population and should be assessed routinely and, where appropriate, addressed through individually-tailored interventions.

Young coronary artery disease in patients undergoing percutaneous coronary intervention

BACKGROUND AND OBJECTIVES

Understanding the nature and pattern of young coronary artery disease (CAD) is important due to the tremendous impact on these patients' socio-economic and physical aspect. Data on young CAD in the southeast Asian region is rather patchy and limited. Hence we utilized our National Cardiovascular Disease Database (NCVD)-Percutaneous Coronary Intervention (PCI) Registry to analyze young patients who underwent PCI in the year 2007 to 2009.

DESIGN AND SETTINGS

This is a retrospective study of all patients who had undergone coronary angioplasty from 2007 to 2009 in 11 hospitals across Malaysia.

METHODS

Data were obtained from the NCVD-PCI Registry, 2007 to 2009. Patients were categorized into 2 groups-young and old, where young was defined as less than 45 years for men and less than 55 years for women and old was defined as more than or equals to 45 years for men and more than or equals to 55 years for women. Patients' baseline characteristics, risk factor profile, extent of coronary disease and outcome on dis.charge, and 30-day and 1-year follow-up were compared between the 2 groups.

RESULTS

We analyzed 10268 patients, and the prevalence of young CAD was 16% (1595 patients). There was a significantly low prevalence of Chinese patients compared to other major ethnic groups. Active smoking (30.2% vs 17.7%) and obesity (20.9% vs 17.3%) were the 2 risk factors more associated with young CAD. There is a preponderance toward single vessel disease in the young CAD group, and they had a favorable clinical outcome in terms of all-cause mortality at discharge (RR 0.49 [CI 0.26-0.94]) and 1-year follow-up (RR 0.47 [CI 0.19-1.15]).

CONCLUSION

We observed distinctive features of young CAD that would serve as a framework in the primary and secondary prevention of the early onset CAD.

The Effect of Intensified Low Density Lipoprotein Cholesterol Reduction on Recurrent Myocardial Infarction and Cardiovascular Mortality

BACKGROUND

Lipid-lowering therapy plays an important role in preventing the recurrence of cardiovascular events in patients after acute myocardial infarction (AMI). This study aimed to assess the effect of intensified low density lipoprotein cholesterol (LDL-C) reduction on recurrent myocardial infarction and cardiovascular mortality in patients after AMI.

METHOD

The 562 enrolled AMI patients (84.2% male) were divided into two groups according to 3-month LDL-C decrease percentage equal to or more than 40% (n = 165) and less than 40% (n = 397). To evaluate the long-term efficacy of LDL-C reduction, the 5-year outcomes were collected, including time to the first occurrence of myocardial infarction and time to cardiovascular death.

RESULTS

The baseline characteristics and complication rates were not different between the two study groups. The patients with 3-month LDL-C decrease ≥ 40% had higher baseline LDL-C and lower 3-month, 1-year, 2-year, 3-year, 4-year and 5-year LDL-C than the patients with 3-month LDL-C decrease < 40%. In Kaplan-Meier analyses, those patients with 3-month LDL-C decrease ≥ 40% had a higher rate of freedom from myocardial infarction (p = 0.006) and survival rate (p = 0.02) at 5-year follow-up. The 3-month LDL-C < 40% parameter was significantly related to cardiovascular death (HR: 9.62, 95% CI 1.18-78.62, p < 0.04).

CONCLUSIONS

After acute myocardial infarction, 3-month LDL-C decrease < 40% was identified to be a significant risk factor for predicting 5-year cardiovascular death. The patients with 3-month LDL-C decrease ≥ 40% had a higher rate of freedom from myocardial infarction and lower cardiovascular mortality, even though these patients had higher baseline LDL-C value.

KEY WORDS

Acute myocardial infarction; Cardiovascular death; Low-density lipoprotein cholesterol; Mortality; Statin.