Effect of Probucol and/or Cilostazol on Carotid Intima Media Thickness in Patients with Coronary Heart Disease: A Randomized, Multicenter, Multinational Study

Early diagnostic value of carotid artery ultrasound parameters combined with epicardial adipose layer thickness in coronary heart disease

BACKGROUND

Coronary heart disease is associated with coronary atherosclerosis indicated by carotid intima-media thickness (CIMT) thickening and altered vascular elasticity. The epicardial adipose layer can secrete proinflammatory factors that promote the formation of coronary atherosclerosis. Thus, the epicardial fat layer thickness (EAT) may also predict coronary heart disease.

AIM

To determine the role of common carotid artery ultrasound parameters and EAT in the early diagnosis of coronary artery disease.

METHODS

Based on coronary angiography, patients with newly suspected coronary heart disease were divided into case (n = 107) and control (n = 41) groups. The carotid ultrasound parameters, including vascular stiffness (β), elastic coefficient (EP), pulse wave conduction velocity (PWV-β), CIMT, and EAT were compared between the case and control groups and among patients with different lesion numbers in the case group. Pearson correlation was used to evaluate the early diagnostic value of EAT, common carotid artery elasticity, and CIMT for coronary heart disease.

RESULTS

EP, β, PWV-β, CIMT, and EAT were significantly higher in the case group compared with the levels in the control group (all P < 0.001). In the case group, lesions were detected in one vessel in 34 patients, two vessels in 38 patients, and three vessels in 35 patients. Within the case group, β, EP, PWV-β, CIMT, and EAT levels significantly increased with an increased number of lesions (all P < 0.001). EAT positively correlated with β, EP, PWV-β, and CIMT (all P < 0.01). The area under the curve for diagnosing coronary heart disease using EAT combined with CIMT and carotid elasticity was 0.893, and the sensitivity and specificity were 0.890 and 0.837.

CONCLUSION

EAT correlated well with changes in carotid artery elasticity and CIMT in patients with coronary heart disease. The combination of EAT, carotid artery elasticity, and CIMT facilitates the early diagnosis of coronary heart disease.

Natural and synthetic antioxidants targeting cardiac oxidative stress and redox signaling in cardiometabolic diseases

Cardiometabolic diseases (CMDs) are metabolic diseases (e.g., obesity, diabetes, atherosclerosis, rare genetic metabolic diseases, etc.) associated with cardiac pathologies. Pathophysiology of most CMDs involves increased production of reactive oxygen species and impaired antioxidant defense systems, resulting in cardiac oxidative stress (OxS). To alleviate OxS, various antioxidants have been investigated in several diseases with conflicting results. Here we review the effect of CMDs on cardiac redox homeostasis, the role of OxS in cardiac pathologies, as well as experimental and clinical data on the therapeutic potential of natural antioxidants (including resveratrol, quercetin, curcumin, vitamins A, C, and E, coenzyme Q10, etc.), synthetic antioxidants (including N-acetylcysteine, SOD mimetics, mitoTEMPO, SkQ1, etc.), and promoters of antioxidant enzymes in CMDs. As no antioxidant indicated for the prevention and/or treatment of CMDs has reached the market despite the large number of preclinical and clinical studies, a sizeable translational gap is evident in this field. Thus, we also highlight potential underlying factors that may contribute to the failure of translation of antioxidant therapies in CMDs.

Integrated Analysis of Two Probucol Trials for the Secondary Prevention of Atherosclerotic Cardiovascular Events: PROSPECTIVE and IMPACT

Aims: In this study, we integrated two randomized control trials, PROSPECTIVE and IMPACT, to address the effect of probucol on cerebrocardiovascular events and carotid intima-media thickness (IMT) in Japanese, Korean, and Chinese patients with coronary artery disease (CAD).

Methods: A total of 1,025 patients from the PROSPECTIVE and IMPACT studies were enrolled. The time to the first major adverse cerebrocardiovascular event, in addition to carotid IMT and lipid levels, was compared between the control and probucol groups.

Results: In the integrated analysis, the adjusted hazard ratio (HR) and 95% confidence interval (CI) were 0.67 and 0.44–1.03, respectively, indicating a tendency to show the effect of probucol on cerebrocardiovascular events in secondary prevention. We also found no significant differences between the control and probucol groups in the mean IMT of the carotid arteries and its changes. However, we found a significant decrease in cerebrocardiovascular events in patients with reduced levels of HDL cholesterol (HDL-C) (≥ 6.25 mg/dL) compared with those with levels ＜6.25 mg/dL (p=0.024), without any increase in adverse events such as severe ventricular arrhythmias.

Conclusion: We demonstrated a marginal effect of probucol on cerebrocardiovascular events in Asian patients with CAD, with reasonable safety profiles. A larger study may be needed to support the effect of probucol for cardiovascular prevention.

Probucol Trial for Secondary Prevention of Atherosclerotic Events in Patients with Coronary Heart Disease (PROSPECTIVE)

AIMS

Although intensive statin therapy reduced cardiovascular risks, cardiovascular events have not been completely prevented. Probucol is a potent antioxidant and reduces tendon xanthomas in familial hypercholesterolemia patients despite reduction of high-density lipoprotein (HDL)-cholesterol (HDL-C). We investigated whether probucol can reduce cardiovascular events on top of conventional lipid-lowering therapy in patients with coronary heart disease (CHD).

METHODS

PROSPECTIVE is a multicenter, randomized, prospective study that recruited 876 Japanese patients with CHD and dyslipidemia with a low-density lipoprotein (LDL)-cholesterol (LDL-C) level of ≥ 140 mg/dL without medication or those treated with lipid-lowering drugs. Lipid-lowering agents were administered during the study period in the control group (n=438), and probucol 500 mg/day was added to lipid-lowering therapy in the probucol group (n=438). Patients were randomly assigned to two treatment groups by adjusting the LDL-C level and presence of diabetes and hypertension and followed up for more than 3 years. The primary end point was a composite of cerebrovascular and cardiovascular events (cardiovascular disease death including sudden death, nonfatal myocardial infarction, nonfatal stroke, hospitalization for unstable angina, hospitalization for heart failure, or coronary revascularization). The secondary end point was carotid intima-media thickness in a subset of patients.

RESULTS

The incidence of the primary end point showed a trend to be lower in the probucol group compared with that in the control group despite reduced HDL-C without serious adverse events. Anti-atherogenic effects of probucol may be attributed to its potent antioxidative function and enhancement of reverse cholesterol transport.

CONCLUSION

Since there was no statistical significance between the probucol and control groups despite a marked reduction of HDL-C, further studies on the clinical outcomes of probucol on top of conventional therapy may be necessary in the future (UMIN000003307).