Myocardial infarction in young adults with low-density lipoprotein cholesterol levels < or = 100 mg/dL: clinical profile and 1-year outcomes

Lipid profile and long-term outcome in premature myocardial infarction

BACKGROUND

Premature myocardial infarction (≤40 years) represents a rare disease with a distinct risk factor profile and a lipid phenotype that is characterized by a predominance of elevated triglyceride-rich lipoproteins. So far high-density and low-density lipoproteins remain the primary targets for risk stratification and treatment evaluation in coronary artery disease, but this strategy might be insensitive in patients with premature myocardial infarction.

AIM

Aim of this study was to investigate the predictive value of different lipid fractions on long-term cardiovascular outcome in patients with premature myocardial infarction.

METHODS

We prospectively enrolled 102 consecutive AMI survivors (≤40 years) in this prospective multicentre study and investigated the influence of the familial combined hypercholesterolaemia phenotype and a corresponding multimarker panel of different lipid fractions on cardiovascular outcome.

RESULTS

Total cholesterol, non-HDL cholesterol, remnant cholesterol and Apo B lipoprotein were significantly higher in patients experiencing MACE as compared to those who did not. The familial combined hypercholesterolaemia phenotype was associated with an unfavourable cardiovascular outcome even after adjustment for potential cofounders (adjusted HR 3.04,95% CI, 1.26-7.34, P = 0.013). Remnant cholesterol revealed the strongest association with MACE (adj.HR 1.94, 95%CI. 1.30-2.99, P = 0.001). Interestingly LDL and HDL revealed no significant impact on cardiovascular outcome in this study cohort.

CONCLUSION

Non-HDL and remnant cholesterol are strongly associated with an unfavourable outcome in patients with premature myocardial infarction and might be the preferred treatment target for lipid-lowering therapy.

Familial hypercholesterolemia in very young myocardial infarction

Familial hypercholesterolemia (FH) is one of the most common causes of premature myocardial infarction (MI). However, The patterns of FH remained unrecognized in clinical care, especially in very young patients (VYPs, ≤35 years) with MI. The present study enrolled a total of 1,093 VYPs (≤35 years) presenting a first MI. Clinical diagnosis of FH was made using Dutch Lipid Clinic Network criteria. Coronary severity was assessed by Gensini score (GS). Patients were followed for a median of 40-months with cardiac death, stroke, MI, post-discharge revascularization or unstable angina as primary endpoints. The detected rates of definite/probable FH were 6.5%. The prevalence reached up to 10.3% in patients ≤25 years. The FH had similar levels of comorbidities but was younger, more likely to be very high risk (VHR) and had higher GS (p < 0.05) than unlikely FH. Notably, the FH on prior lipid-lowering medication presented a lower GS compared to those untreated. Differences in event rates were similar in FH as unlikely FH (11.8% vs. 8.1%, adjusted hazard ratio 1.35 [0.64–2.86], p = 0.434) but patients on treatment improved outcome (6.5% vs. 10.5%, adjusted hazard ratio 0.35[0.13–0.95], p = 0.039). The early identification and treatment might be critical to reduce cardiovascular risk in VYPs with MI.

Lipid profile of patients with acute myocardial infarction and its correlation with systemic inflammation

The biomarker potential of using various lipids fractions for predicting risk of acute myocardial infarction (AMI) is controversial. We therefore compared the lipid profiles, including serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL) and triglycerides (TG), in 67 AMI patients. Patients included 28 STEMI (ST-elevated myocardial infarction) patients, 39 NSTEMI (non-ST-elevated myocardial infarction) patients and 25 patients with chest pain. Control group included 54 age- and gender-matched normal subjects. We also studied the correlation between lipid profile and systemic inflammation in these subjects. There were significant decreases in TC, LDL and HDL levels in both STEMI and NSTEMI patients as compared to normal subjects; however, patients with chest pain did not show any significant change in these lipids. Serum TG levels did not differ significantly among the study groups. There were significant increases in serum high-sensitive C-reactive protein (hs-CRP) levels in STEMI and NSTEMI patients, as compared to control group. Serum hs-CRP showed significant inverse correlation with HDL; however, hs-CRP was not correlated with TC, LDL, and TG. In conclusion, our findings suggest that reduction in serum TC does not prevent the risk of AMI, whereas a decrease in serum HDL and increase in hs-CRP strongly predisposes the risky individuals to an AMI event. We emphasize the importance of HDL and CRP measurements for the assessment of a combined lipid-inflammation risk factor that could be a useful predictor of high risk individuals, as well as a prognostic marker in AMI patients.

Acute coronary syndrome in young adults from oman: results from the gulf registry of acute coronary events

OBJECTIVE

To assess the prevalence, risk factors, presenting features, and in-hospital outcomes of acute coronary syndrome (ACS) patients ≤40 years of age from Oman.

METHODS

Data were analyzed from 1579 consecutive ACS patients from Oman during May, 2006 to June, 2007, as part of Gulf RACE (Registry of Acute Coronary Events). ACS patients ≤40 years of age were compared with patients >40 years of age.

RESULTS

A total of 121 (7.6%) patients were ≤40 years of age with mean age of 36 ± 4 vs. 61 ± 11 years in young and old adults, respectively (P<0.001). More men were seen in the younger age group (81 vs. 60%; P<0.001). Among all the coronary risk factors, young patients had more history of smoking (47 vs. 15%; P<0.001), obesity (72 vs. 58%; P = 0.009), and family history of coronary artery disease (CAD) (16 vs. 7%; P = 0.001). Both groups received aspirin, statins, thrombolytic therapy, and anticoagulants equally; however, younger patients received clopidogrel, glycoprotein IIb/IIIa inhibitors, β-blockers, and in-hospital coronary angiogram more. Younger patients experienced less heart failure (6 vs. 27%; P<0.001) and in-hospital mortality, especially among STEMI patients (0 vs. 10%; P = 0.037).

CONCLUSIONS

Young ACS patients from Oman have different risk profile. They were treated more aggressively and their outcome was better, which is similar to other populations. However, smoking, along with obesity and family history of CAD were strong risk factors in the young Omani ACS patients. There is a need for prevention programmes to control smoking and obesity epidemic by targeting young adults in the population.

Metabolic Syndrome and Coronary Heart Disease Equivalent Conditions in Predicting Cardiovascular Events in Young to Middle-Aged Adults

There are questions concerning the validity of the metabolic syndrome as a diagnostic entity and whether the syndrome predicts coronary heart disease (CHD) better than global risk stratification. The use of the metabolic syndrome as a potential adjunct to improve global risk stratification has received less attention. The authors evaluated the relationship between the metabolic syndrome and cardiovascular disease compared with coronary heart disease equivalent. Two hundred thirty-six subjects undergoing elective coronary angiography had bilateral carotid ultrasound studies and global risk scores calculated. Mean total, low-density lipoprotein, and high-density lipoprotein cholesterol and triglyceride values were normal. The metabolic syndrome was associated with carotid atherosclerosis (odds ratio, 2.3; confidence interval, 1.2-4.2), coronary disease (odds ratio, 2.9; confidence interval, 1.6-5.4), and future cardiovascular events. Rates for future events and coronary and carotid atherosclerosis were similar for subjects with the metabolic syndrome compared with coronary heart disease equivalent. Combined, the two conditions identified 70% of subjects who developed events. The metabolic syndrome is associated with cardiovascular disease and provides additive information to clinical risk stratification.

Clinical characteristics and mid-term prognosis of acute coronary syndrome in HIV-infected patients on antiretroviral therapy

OBJECTIVES

Acute coronary syndromes (ACSs) and coronary artery disease are emerging complications in HIV-infected patients on highly active antiretroviral treatment. The aim of this study was to determine the mid-term prognosis of ACS in HIV-infected patients.

METHODS

We evaluated the clinical characteristics and follow-up profile [38+/-15 months; mean+/-standard deviation (SD)] of ACS in 20 HIV-infected patients (mean +/-SD: age 44+/-8 years; range 35-65 years). All had coronary angiograms performed mean time 3+/-48 h after the onset of symptoms.

RESULTS

Eighteen patients were on antiretroviral therapy, of whom 13 patients were on regimens including protease inhibitors (mean duration+/-SD: 19+/-13 months). Fifteen patients had a first episode of ST segment elevation ACS and five had non-ST segment elevation ACS. Tobacco consumption (80%) and hypercholesterolaemia (50%) were the most frequent cardiovascular risk factors. During initial hospitalization, four patients were treated with thrombolysis, two had primary coronary angioplasty and seven had secondary coronary angioplasty. At follow up, 10 patients (50%) had had 18 cardiovascular events: one cardiovascular death, seven episodes of recurrent myocardial ischaemia in four patients, three pulmonary oedemas in two patients, and seven revascularization procedures in five patients.

CONCLUSIONS

This preliminary report highlights the risk of ACS and related complications in HIV-infected patients and raises questions regarding the implications of antiretroviral treatment.

Acute myocardial infarction and thyrotoxic storm--a difficult and dangerous combination

We describe an unusual case of acute myocardial infarction (AMI) and cardiogenic shock in a 25-year-old woman. After coronary revascularization, a thyrotoxic storm developed and the patient's cardiac failure changed into a hyperdynamic circulation without obvious changes in the patient's vital signs. This report will focus on three issues: (1) the benefit of advanced hemodynamic monitoring in circulatory unstable patients, (2) the confounding effects of untreated hyperthyroidism on the circulation, and (3) previous cancer treatment as a cause of AMI in young persons.

Preventing myocardial infarction in the young adult in the first place: how do the National Cholesterol Education Panel III guidelines perform?

OBJECTIVES

The purpose of this study was to investigate the utility of the new National Cholesterol Education Program (NCEP) III guidelines in a group of young adults.

BACKGROUND

These guidelines have been hailed as an improvement in their potential to identify individuals at risk for coronary heart disease (CHD) complications. Compared with the NCEP II, the new guidelines will increase the number of patients who qualify for medical management. However, the effectiveness of these guidelines to identify young adults at risk for a cardiac event is yet to be studied.

METHODS

A retrospective review of clinical data from young adults (age <or=55 years for men and <or=65 years for women) hospitalized for acute myocardial infarction over a three-year period was conducted. Patients with a history of CHD or CHD equivalent were excluded. Using the NCEP III guidelines, we calculated a 10-year risk for coronary events on all patients.

RESULTS

A total of 222 patients met criteria for inclusion. The mean age was 50 years and 25% were women. Mean lipid levels were all within the normal range; however, rates of smoking and obesity were high. When the 10-year risk of these patients was stratified by the number of risk factors and low-density lipoprotein cholesterol level, only 25% met criteria to qualify for pharmacotherapy. For women in this population, only 18% met criteria for treatment.

CONCLUSIONS

The new guidelines offer multiple new features but have a tendency to underappreciate the risk for disease in young adults. To improve performance in young adults, statistical adjustments may be necessary.

Using a systemwide care path to enhance compliance with guidelines for acute myocardial infarction

BACKGROUND

Several acute myocardial infarction (MI) guidelines and policy statements have been developed, but compliance rates are suboptimal. The cardiology section at Gundersen Lutheran Medical Center (La Crosse, Wisconsin) used a systemwide approach to enhance compliance with guidelines.

METHODS AND RESULTS

Data were collected prospectively for a 4-year period (May 15, 1995-May 15, 1999) for all patients presenting with acute MI. In 1995 a multidisciplinary team developed protocols for each phase of MI management and designed clinical care paths with built-in accountability. The initiative resulted in improvements in all phases of acute MI care and met the benchmark recommendations in mean time to electrocardiogram, thrombolytic therapy, and aspirin and beta-blocker administration. Rates of prescriptions for secondary prevention were 92% for aspirin and beta-blocker and 97% for smoking cessation education at 4 years.

SUMMARY

The care path for acute MI involved multiple disciplines and empowerment of nonspecialists and nonphysician practitioners during development and implementation, as well as continual education and retraining. The care path led to several improvements in performance scores. These findings indicate that the recommendations as set forth in the American College of Cardiology (ACC) and the American Heart Association (AHA) guidelines for managing acute MI are realistic and achievable, and they do not require additional resources.