Can proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors regress coronary atherosclerotic plaque? A systematic review and meta-analysis

OBJECTIVE

Whether inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes the regression of coronary atherosclerotic plaque in statin-treated individuals remains unclear. This study examined whether PCSK9 inhibitors combined with statin therapy could increase atherosclerotic plaque regression compared with statin therapy alone.

METHODS

PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL), the database Clinical trials, and the Web of Science were searched to report the coronary atherosclerotic plaque of PCSK9 inhibitors using intravascular ultrasonography (IVUS) or optical coherence tomography (OCT) in statin patients. The weighted mean difference (WMD) of the random-effects/fixed-effects model was used to pool data that satisfied our inclusion criteria obtained from the included studies.

RESULTS

When compared with statin therapy alone, pooled studies revealed that PCSK9 inhibitors combined with statin therapy significantly decreased percent atheroma volume (PAV) (WMD: -1.06%, 95% confidence interval [CI]: -1.39 to -0.73; P<0.001) and total atheroma volume (TAV) (WMD: -6.38 mm³, 95% CI: -10.12 to -2.64; P=0.001). Moreover, the fibrous cap thickness (FCT) of the coronary atherosclerotic plaque increases to 21.31 um (WMD: 21.31, 95% CI: 7.08 to 35.53, P<0.001), and the maximum lipid arc decreases 10.9° (WMD: -10.9, 95% CI: -15.24 to -5.34, P<0.001).

CONCLUSION

In our systematic review and meta-analysis, PCSK9 inhibitors combined with statin therapy were found to be more effective than statin therapy alone for slowing coronary plaque progression by decreasing PAV, TAV, and increasing FCT, maximum lipid arc.

Effects of different statins application methods on plaques in patients with coronary atherosclerosis

BACKGROUND

Discontinued application of statins may be related to adverse cardiovascular events. However, it is unclear whether different statins administration methods have effects on coronary artery plaques.

AIM

To evaluate the effects of different statins application methods on plaques in patients with coronary atherosclerosis.

METHODS

A total of 100 patients diagnosed with atherosclerotic plaque by coronary artery computed tomography were continuously selected and divided into three groups according to different statins administration methods (discontinued application group, n = 32; intermittent application group, n = 39; sustained application group, n = 29). The effects of the different statins application methods on coronary atherosclerotic plaque were assessed.

RESULTS

The volume change and rate of change of the most severe plaques were significantly reduced in the sustained application group (P ≤ 0.001). The volume change of the most severe plaques correlated positively with low-density lipoprotein (LDL-C) levels only in the sustained application group (R = 0.362, P = 0.013). There were no changes in plaques or LDL-C levels in the intermittent and discontinued application groups.

CONCLUSION

Continuous application of statins is effective for controlling plaque progression, whereas discontinued or intermittent administration of statins is not conducive to controlling plaques. Only with continuous statins administration can a reduction in LDL-C levels result in plaque volume shrinkage.

The effect of combined ezetimibe and statin therapy versus statin therapy alone on coronary plaque volume assessed by intravascular ultrasound: A systematic review and meta-analysis

BACKGROUND

Current guidelines recommend an intensive lipid-lowering therapy to achieve the low-density lipoprotein cholesterol (LDL-C) target in patients with high risk of cardiovascular disease. Former studies suggested adding ezetimibe to statin therapy in the above setting may promote plaque changes; however, this effect has not been consistently reported.

METHODS

Electronic searches were performed in MEDLINE, EMBASE, and Cochrane library on November 30, 2017 to identify prospective trials assessing the effects of combined ezetimibe and statin therapy versus statin therapy alone on atheroma volume using intravascular ultrasound. The effect size between treatment groups within individual studies was assessed by weighted mean difference (MD) using a random-effects model.

RESULTS

Eight studies were obtained for systematic review and 6 of them compromising total of 583 subjects that meet the criteria were meta-analyzed. There was a significant reduction from baseline to follow-up in total atheroma volume with an MD of -3.71 mm³ (95% confidence interval: -5.98 to -1.44, P < .001), whereas analysis for percent atheroma volume demonstrated weighted MD of - 0.77% (-1.68 to 0.14, P = .10). A substantial decrease in LDL-C was observed with MD -16.75 mg/dL (-20.89 to -12.60, P < .00001).

CONCLUSION

The addition of ezetimibe to statin therapy is effective in reducing total atheroma volume assessed by intravascular ultrasound and also resulted in effective reduction of plasma LDL-C levels.

Computed tomography-based high-risk coronary plaque score to predict acute coronary syndrome among patients with acute chest pain--Results from the ROMICAT II trial

BACKGROUND

Coronary computed tomography angiography (CTA) can be used to detect and quantitatively assess high-risk plaque features.

OBJECTIVE

To validate the ROMICAT score, which was derived using semi-automated quantitative measurements of high-risk plaque features, for the prediction of ACS.

MATERIAL AND METHODS

We performed quantitative plaque analysis in 260 patients who presented to the emergency department with suspected ACS in the ROMICAT II trial. The readers used a semi-automated software (QAngio, Medis medical imaging systems BV) to measure high-risk plaque features (volume of <60HU plaque, remodeling index, spotty calcium, plaque length) and diameter stenosis in all plaques. We calculated a ROMICAT score, which was derived from the ROMICAT I study and applied to the ROMICAT II trial. The primary outcome of the study was diagnosis of an ACS during the index hospitalization.

RESULTS

Patient characteristics (age 57 ± 8 vs. 56 ± 8 years, cardiovascular risk factors) were not different between those with and without ACS (prevalence of ACS 7.8%). There were more men in the ACS group (84% vs. 59%, p = 0.005). When applying the ROMICAT score derived from the ROMICAT I trial to the patient population of the ROMICAT II trial, the ROMICAT score (OR 2.9, 95% CI 1.4-6.0, p = 0.003) was a predictor of ACS after adjusting for gender and ≥ 50% stenosis. The AUC of the model containing ROMICAT score, gender, and ≥ 50% stenosis was 0.91 (95% CI 0.86-0.96) and was better than with a model that included only gender and ≥ 50% stenosis (AUC 0.85, 95%CI 0.77-0.92; p = 0.002).

CONCLUSIONS

The ROMICAT score derived from semi-automated quantitative measurements of high-risk plaque features was an independent predictor of ACS during the index hospitalization and was incremental to gender and presence of ≥ 50% stenosis.

Impact of abdominal and epicardial fat on the association between plasma adipocytokine levels and coronary atherosclerosis in non-obese patients

OBJECTIVE

Ectopic fat accumulation is associated with coronary artery disease. Visceral adipose tissue has paracrine and systemic effects and is a source of adipocytokines. It has been implicated in the pathogenesis of coronary atherosclerosis; however, nothing is known about whether increases in epicardial fat have the same effect on coronary atherosclerosis as increases in abdominal visceral fat.

METHODS

We examined 216 consecutive patients suspected to have coronary artery disease. Individuals with acute coronary syndrome and inadequate computed tomography (CT) imaging were excluded. We enrolled 164 patients (65 ± 10 years old; 70% men; body mass index [BMI], 23.8 ± 3.6 kg/m(2)). The plasma concentrations of adiponectin, interleukin-6 (IL-6), plasminogen activator inhibitor-1, and vascular endothelial growth factor were measured. The characteristics of coronary plaque, abdominal visceral fat area, and epicardial fat volume (EFV) were determined by 64-slice CT imaging.

RESULTS

EFV was greater in subjects with noncalcified plaque than in those with no plaque or with calcified plaque (126 ± 39 mL vs. 98 ± 34 mL and 97 ± 45 mL, respectively; P = 0.010). EFV was significantly correlated with BMI, triglycerides, and the triglyceride/high-density lipoprotein cholesterol ratio (r = 0.51, 0.19, and 0.20, respectively) but not with plasma levels of adipocytokines. The plasma adiponectin and IL-6 concentration was significantly correlated with abdominal visceral fat area in coronary plaque patients (r = -0.49 and 0.20).

CONCLUSIONS

In non-obese Japanese patients, epicardial fat may have unique mechanisms affecting the development of coronary atherosclerosis, which is different from abdominal visceral fat.

Correlation of concentrations of high-sensitivity troponin T and high-sensitivity C-reactive protein with plaque progression as measured by CT coronary angiography

BACKGROUND

Elevated levels of inflammatory biomarkers are associated with increased cardiovascular morbidity and mortality.

OBJECTIVE

We sought to determine whether elevated concentrations of high-sensitivity troponin T (hs-TnT) and high-sensitivity C-reactive protein (hs-CRP) predict progression of coronary artery disease (CAD) as determined by coronary CT angiography (coronary CTA).

METHODS

Patients presenting to the emergency department with acute chest pain who initially showed no evidence of an acute coronary syndrome underwent baseline and follow-up coronary CTA (median follow-up, 23.9 months) using identical acquisition and reconstruction parameters. Coronary CTA data of each major coronary artery were co-registered. Cross-sections were assessed for the presence of calcified and noncalcified plaques. Progression of atherosclerotic plaque and change of plaque composition from noncalcified to calcified plaque was evaluated and correlated to levels of hs-TnT and hs-CRP at the time of the baseline CT.

RESULTS

Fifty-four patients (mean age, 54.1 years; 59% male) were included, and 6775 cross-sections were compared. CAD was detected in 12.2 ± 21.2 cross-sections per patient at baseline. Prevalence of calcified plaque increased by 1.5 ± 2.4 slices per patient (P < .0001) over the follow-up period. On average, 1.6 ± 3.6 slices with new noncalcified plaque were found per patient (P < .0001) and 0.7 ± 1.7 slices with pre-existing noncalcified plaque had progressed to calcified plaque (P < .0001). After multivariate adjustment, change of overall CAD burden was predicted by baseline hs-TnT and hs-CRP (r = 0.29; P = .039 and r = 0.40; P = .004). Change of plaque composition was associated with baseline hs-TnT (r = 0.29; P = .03).

CONCLUSION

Concentrations of hs-TnT and hs-CRP are weakly associated with a significant increase in CAD burden and change in plaque composition over 24 months independent of baseline risk factors.

Prognosis of patients with mild-moderate coronary artery stenosis detected by coronary computed tomography angiography

BACKGROUND

In addition to the diagnostic performance, coronary computed tomography angiography (CTA) can give important data regarding the prognosis of coronary artery disease (CAD). In this study we aimed to evaluate the prognostic role of coronary CTA in patients with suspected CAD and mild-moderate coronary stenosis.

METHODS

A total of 1115 patients (602 male, 54%; age 58.4 ± 11.4) without previous CAD were enrolled. Patients underwent coronary CTA imaging using dual-source 64-slice CT scanner. For categorization of the coronary atherosclerotic plaques (CAP), the coronary system was divided into 16 separate segments. For each segment, CAPs were categorized as: calcified, noncalcified and mixed.

RESULTS

During follow-up of 29.7 ± 13.2 months, cardiovascular events defined as ST segment elevation myocardial infarction (4 patients), non-ST segment elevation myocardial infarction (5 patients) and unstable angina pectoris (20 patients) requiring revascularization or hospital admission were recorded. Cox hazard regression analysis revealed an association between the severity of luminal stenosis (HR: 4.73, 95% CI: 1.36-16.47, p<0.05) and extent (HR: 1.10, 95% CI: 1.00-1.22, p=0.051) and the adverse coronary events in the follow-up. Multivariate Cox hazard regression analysis revealed that nonobstructive (≤ 50%) lesions were the only factor causing increased probability of coronary events in the follow-up (HR: 4.77, 95% CI: 1.36-16.74, p<0.05).

CONCLUSION

The presence and severity of luminal stenosis shown by coronary CTA were associated with prognosis of coronary events in the follow-up. These results may improve the risk stratification in patients evaluated by coronary CTA and provide strategies for the individualized prevention programs.