Associations between C-reactive protein, coronary artery calcium, and cardiovascular events: implications for the JUPITER population from MESA, a population-based cohort study

The prognostic significance of coronary CT angiography

Coronary computed tomography angiography (CTA) is an increasingly utilized, highly accurate noninvasive test for the diagnosis of coronary artery disease. Accumulating data have convincingly demonstrated that the presence, extent, and location of both obstructive and nonobstructive coronary atherosclerosis visualized on coronary CTA conveys powerful prognostic information, incremental to that provided by clinical variables and coronary calcium scoring. Proposed markers of future plaque instability and coronary risk, such as the degree of vessel remodeling and low-attenuation plaque volume, as well as measures of CT myocardial perfusion, may further improve the prognostic value of CTA. Ultimately, studies are needed to assess whether the prognostic information provided by coronary CTA testing results in sustained changes in patient and provider behaviors that cost effectively improve patient outcomes.

Effects of lifestyle modification and metformin on atherosclerotic indices among HIV-infected patients with the metabolic syndrome

OBJECTIVE

Metabolic abnormalities including diabetes, dyslipidemia, hypertension, and abdominal obesity occur commonly in HIV patients, are associated with increased coronary artery calcification (CAC), and contribute to increased cardiovascular disease (CVD) in this population. We hypothesized that lifestyle modification (LSM) and metformin would improve CVD indices in HIV patients with metabolic syndrome.

DESIGN

A randomized, placebo-controlled trial to investigate LSM and metformin, alone and in combination, over 1 year, among 50 HIV-infected patients with metabolic syndrome.

METHODS

We assessed CAC, cardiovascular and metabolic indices.

RESULTS

Among the participants, duration of HIV-infection was 14 ± 1 year and duration of antiretroviral therapy was 6 ± 1 year. Metformin-treated patients demonstrated significantly less progression of CAC (-1 ± 2 vs. 33 ± 17, P = 0.004, metformin vs. placebo), whereas the effect of LSM on CAC progression was not significant (8 ± 6 vs. 21 ± 14, P =  0.82, LSM vs. no-LSM). Metformin had a significantly greater effect on CAC than LSM (P = 0.01). Metformin-treated patients also demonstrated less progression in calcified plaque volume (-0.4 ± 1.9 vs. 27.6 ± 13.8 μl, P = 0.008) and improved homeostatic model of assessment-insulin resistance (HOMA-IR) (P = 0.05) compared with placebo. Participants randomized to LSM vs. no-LSM showed significant improvement in HDL (P = 0.03), high-sensitivity C-reactive protein (hsCRP) (P = 0.05), and cardiorespiratory fitness. Changes in CAC among the four groups--no-LSM-placebo (43 ± 30); LSM-placebo (19 ± 7); no-LSM-metformin (1 ± 1) and LSM-metformin (-4 ± 6)--were different (P = 0.03 for ANOVA and linear trend across groups), and the majority of this effect was mediated by metformin. Results are mean ± SEM.

CONCLUSION

Metformin prevents plaque progression in HIV-infected patients with the metabolic syndrome.

Acute coronary events

In the United States alone, more than 400,000 Americans die annually from coronary artery disease and more than 1,000,000 suffer acute coronary events, i.e., myocardial infarction and sudden cardiac death.1 Considering the aging of our population and increasing incidence of diabetes and obesity, the morbidity from coronary artery disease, and its associated costs, will place an increasing, substantial burden on our society.2 Between 2010 and 2030, total direct medical costs spent in the US for cardiovascular diseases are projected to triple from 273 to 818 billion dollars.2 Although effective treatments are available and considerable efforts are ongoing to identify new strategies for the prevention of coronary events, predicting such events in an individual has been challenging.3 In hopes of improving our ability to determine the risk of coronary events, it is prudent to review our knowledge of factors that lead to acute coronary events.

[Update on ischemic heart disease]

This article contains a review of the main developments reported in 2011 on the pathophysiology, prevention, prognosis and treatment of chronic coronary artery disease and acute coronary syndrome, with or without ST-segment elevation. It also discusses the recommendations of the latest clinical practice guidelines.