Intensive cholesterol-lowering therapy improves large artery elasticity in acute myocardial infarction patients

Ankle-Brachial Index: Diagnostic Tool of Peripheral Arterial Disease and Predictor of Cardiovascular Risk-An Update of Current Knowledge

The ankle-brachial index (ABI) was introduced as a screening method for the diagnosis of lower extremity peripheral arterial disease (PAD). Later findings recognized ABI as a prognostic marker of adverse cardiovascular events due to its relation to atherosclerosis in other vascular territories. This narrative review aims to appraise the validity, reliability, and utility of ABI in the detection of PAD and the determination of global atherosclerotic cardiovascular risk. While the ABI value can be influenced by different physiological characteristics including age, sex, body position, and techniques used for ABI determination, it has high specificity and reproducibility in the assessment of vascular patients. In conclusion, when used correctly, the ABI remains a reliable and invaluable indicator of lower-limb perfusion and a useful tool for predicting the risk of future cardiovascular events. However, its underutilization in clinical settings is noteworthy.

Association Between Telomere G-Tail Length and Coronary Artery Disease or Statin Treatment in Patients With Cardiovascular Risks - A Cross-Sectional Study

Background: The utility of telomere G-tail length to predict coronary artery disease (CAD) remains controversial. CAD results from coronary artery narrowing due to cholesterol and lipid accumulation, augmented by inflammatory cells and other factors. This study explored the significance of telomere G-tail length in suspected CAD patients. Methods and Results: In all, 95 patients with suspected CAD or ≥1 cardiac risk factor underwent coronary computed tomography angiography (CCTA). We measured leukocyte telomere length and G-tail length using a hybrid protection method, and diagnosed the presence of CAD using CCTA. Associations between G-tail length and the presence of CAD, the number of stenosed coronary arteries, and brachial-ankle pulse wave velocity (baPWV) were analyzed. No significant difference was observed in G-tail length when comparing groups with or without CAD or statin treatment. However, in the non-statin group, G-tail length was significantly shorter in patients with 3-vessel disease compared with 1-vessel disease. Dividing the group using a baPWV of 1,300 cm/s, telomere G-tail length was significantly shorter in the high-risk (baPWV ≥1,300 cm/s) group. Conclusions: The clinical utility of telomere G-tail length as a CAD risk indicator seems limited. There was a trend for longer telomere G-tail length in the statin-treated group. Moreover, telomere G-tail length was reduced in patients at high-risk of cardiovascular events, aligning with the trend of a shortening in telomere G-tail length with CAD severity.

Effects of High- or Moderate-intensity Rosuvastatin on 1-year Major Adverse Cardiovascular Events Post-percutaneous Coronary Intervention

Background: Although statins decrease mortality in coronary artery disease, the effect of high-dose statins and duration of therapy post-percutaneous coronary intervention (PCI) is not well addressed. Aim: To determine the effective dose of statin to prevent major adverse cardiovascular events (MACEs), such as acute coronary syndrome, stroke, myocardial infarction, revascularisation and cardiac death, after PCI in patients with chronic coronary syndrome. Methods: In this randomised, double-blind clinical trial, all chronic coronary syndrome patients with a recent history of PCI were randomly divided into two groups after 1 month of high-dose rosuvastatin therapy. Over the next year, the first group received rosuvastatin 5 mg daily (moderate intensity), while the second received rosuvastatin 40 mg daily (high intensity). Participants were evaluated in terms of high-sensitivity C-reactive protein and MACEs. Results: The 582 eligible patients were divided into group 1 (n=295) and group 2 (n=287). There was no significant difference between the two groups in terms of sex, age, hypertension, diabetes, smoking, previous history of PCI or history of coronary artery bypass grafting (p>0.05). There were no statistically significant differences in MACE and high-sensitivity C-reactive protein after 1 year between the two groups (p=0.66). Conclusion: The high-dose group had lower LDL levels. However, given the lack of association between high-intensity statins and MACEs in the first year after PCI among chronic coronary syndrome patients, the use of moderate-intensity statins may be as effective as high-intensity statins, and treatment based on LDL targets may suffice.

Improvement in Brachial Endothelial Vasomotor Function and Brachial-Ankle Pulse Wave Velocity Reduces the Residual Risk for Cardiovascular Events after Optimal Medical Treatment in Patients with Coronary Artery Disease

AIM

To examine whether improvement in flow-mediated endothelium-dependent dilatation (FMD) of the brachial artery and brachial-ankle pulse wave velocity (baPWV) has an additive effect on achieving optimal goals of traditional risk factors to reduce cardiovascular risk in patients with coronary artery disease (CAD).

METHODS

We assessed 323 patients with CAD and impaired vascular function, defined as an impaired FMD of the brachial artery (＜5.5%) and increased baPWV (＞1,440 cm/sec). After FMD and baPWV measurements at 24 weeks of optimal medical treatment (OMT), the study patients were followed up for ＜60 months or until a composite of cardiac death, nonfatal myocardial infarction (MI), unstable angina, or ischemic stroke occurs.

RESULTS

During the median follow-up period of 35 months, cardiovascular events occurred in 72 patients. Multivariate Cox hazards analysis showed that patients with an improvement in FMD and baPWV had the lowest probability of future cardiovascular events. In addition, the improvement in FMD and baPWV had a significant incremental effect on the predictive value of the achievement of optimal goals for blood pressure (BP), low-density lipoprotein cholesterol (LDL-C), and hemoglobin A1c (HbA1c) using net reclassification improvement (NRI) and integrated discrimination improvement (IDI).

CONCLUSIONS

The improvement in FMD and baPWV had additive effects on risk reduction of the achievement of the optimal goals of traditional risk factors in patients with CAD. Thus, serial measurements of FMD and baPWV may be useful for identifying CAD patients at residual risk for adverse cardiovascular events following OMT.

Improving Arterial Wall Characteristics in Patients After Myocardial Infarction with a Very Low Dose of Fluvastatin and Valsartan: A Proof-of-Concept Study

BACKGROUND We tested the concept of improving arterial wall characteristics by treatment with a very low-dose combination of fluvastatin and valsartan (low-flu/val) in stable, post-myocardial infarction (MI) patients. MATERIAL AND METHODS We enrolled 36 post-MI middle-aged males in the treatment (n=20) or control (n=16) group receiving low-flu/val (10 mg/20 mg) or placebo, respectively. The parameters of endothelial function (flow-mediated dilatation (FMD), reactive hyperemia index), and arterial stiffness (carotid-femoral pulse wave velocity (cf-PWV), local carotid PWV, and beta stiffness coefficient) were measured before and after 30 days of therapy, and 10 weeks later. RESULTS Treatment with low-flu/val improved FMD from 3.1±1.3% to 4.8±1.5% (p<0.001; by 54.8%) and cf-PWV from 7.8±1.1 to 6.7±1.5 m/s (p<0.01; by 14.1%) without affecting either lipids or blood pressure. In the treatment group, FMD and/or cf-PWV significantly improved in 17 patients, but the improvements did not correlate. The benefits obtained were still detectable 10 weeks after complete treatment cessation. No changes were obtained in the control group. No other vascular parameters changed. CONCLUSIONS Low-flu/val added "on top of" optimal therapy substantially improves endothelial function and arterial stiffness in post-MI patients. Since these improved parameters are well-known predictors of future coronary events, such treatment could decrease cardiovascular risk. Further studies are therefore warranted.

A Combination of Low Doses of Fluvastatin and Valsartan Decreases Arterial Stiffness in Patients After Myocardial Infarction: A Pilot Study

Background

Despite optimum treatment, patients who experience myocardial infarction are still at high risk for future events.

Objective

We evaluated the effect of 30 days of treatment with combination of low, subtherapeutic doses of fluvastatin and valsartan on arterial stiffness in patients after myocardial infarction, a therapy that has not been used yet.

Methods

Fourteen male patients with a history of myocardial infarction were enrolled into a pilot double-blind randomized controlled study. They were allocated to receive 10 mg fluvastatin and 20 mg valsartan or placebo for 30 days in addition to their regular pharmacotherapy. Carotid–femoral pulse wave velocity was measured on inclusion, after 30 days, and after 3 months.

Results

Mean (SD) carotid–femoral pulse wave velocity decreased significantly in the treatment group after 30 days and persisted at lower values after 3 months (from 8.4 [1.5] m/sec to 7.3 [1.1] m/sec to 7.2 [0.8] m/sec; P < 0.05). The 95% CI for decrease after 30 days in the treatment group was 0.5–1.6. Only nonsignificant changes were observed in the control group. Serum lipid levels and arterial blood pressure did not change significantly in any group.

Conclusions

The treatment resulted in a significant and sustained improvement of arterial stiffness in male patients with a history of myocardial infarction, which highlights the need for further study of this new approach.

Impacts of age on coronary atherosclerosis and vascular response to statin therapy

Age is a well-established risk factor for cardiovascular disease. Recent trials using intravascular ultrasound (IVUS) have shown that lipid-lowering therapy with statins halts the progression or induces the regression of coronary artery plaques. However, impacts of age on coronary atherosclerosis and vascular response to statin therapy have not been fully evaluated. The effects of 8-month statin therapy on coronary atherosclerosis were evaluated using virtual histology-IVUS. IVUS data were analyzed from 119 patients who were divided into two groups according to age: elderly patients (≥65 years, n = 72) and non-elderly patients (<65 years, n = 47). No patients were taking statins or other lipid-lowering therapies at baseline. At baseline, external elastic membrane (EEM) volume (17.27 vs. 14.95 mm(3)/mm, p = 0.02) and plaque volume (9.49 vs. 8.11 mm(3)/mm, p = 0.03) in the elderly patients were significantly greater than in the non-elderly patients. The EEM volume (-2.4 %, p = 0.007) and plaque volume (-3.1 %, p = 0.007) after 8-month of statin therapy had significantly decreased in the non-elderly patients but not in the elderly patients. A significant positive correlation was observed between age and percentage change in plaque volume (r = 0.265, p = 0.004). A multivariate regression analysis showed that age was a significant predictor of the percentage change in plaque volume during statin therapy (β = 0.223, p = 0.02). Coronary atherosclerosis was more advanced and vascular responses to statin therapy were attenuated in the elderly patients compared to the non-elderly patients.

Effects of low-dose atorvastatin on arterial stiffness and central aortic pressure augmentation in patients with hypertension and hypercholesterolemia

BACKGROUND

Experimental and clinical data suggest that statins exert anti-inflammatory and antiproliferative actions on vasculature beyond their lipid-lowering properties. Whether these pleiotropic effects of statins translate into a beneficial effect on arterial stiffness is not clear. This study aimed to evaluate the potential effects of low-dose atorvastatin treatment on arterial stiffness and central arterial pressure waveforms in patients with mild hypertension and hypercholesterolemia.

METHODS

In a double-blind, randomized, placebo-controlled fashion, 50 hypertensive and hypercholesterolemic patients were allocated to receive 10 mg of atorvastatin or placebo for 26 weeks. Arterial stiffness was assessed by aortic pulse-wave velocity (PWV) using a Sphygmocor device. Central arterial pressure waveform parameters were estimated by radial artery applanation tonometry. Heart rate-adjusted augmentation index (AIx(75)) was used as measure of wave reflections.

RESULTS

At study end, aortic PWV (9.0 ± 1.5 vs. 10.9 ± 2.6 m/sec; P < 0.001) and AIx(75) (24.9% ± 9.7% vs 28.8% ± 11.8%; P < 0.001) were significantly lower in the atorvastatin group than that placebo group. Furthermore, decreases in central aortic systolic blood pressure and pulse pressure were evident at study-end with atorvastatin but not with placebo (130 ± 8 vs. 138 ± 6 mm Hg, P < 0.001; 48 ± 7 vs. 53 ± 6 mm Hg, P < 0.05, respectively). Atorvastatin-induced reductions in aortic PWV during follow-up showed significant associations with changes in AIx(75) and central aortic systolic blood pressure and pulse pressure.

CONCLUSIONS

This study shows that low-dose atorvastatin treatment improves arterial stiffness and exerts a reduction on central aortic pressures. These effects may represent a potential mechanism of cardiovascular risk reduction observed with statin use.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Database Identifier Number: NCT01126684.

Development of a model for prediction of coronary atherosclerotic regression: evaluation of high-density lipoprotein cholesterol level and peripheral blood monocyte count

Monocytes and high-density lipoprotein cholesterol (HDL-C) play important roles in the process of coronary atherosclerosis. We hypothesized that a reasonable predictive model of coronary plaque regression might be constructed using the change in the peripheral monocyte count and the serum HDL-C level. The plaque volume, as assessed by volumetric intravascular ultrasound, was measured at the baseline and after 6 months of pravastatin therapy in 114 patients with coronary artery disease. After 6 months of pravastatin therapy, a significant decrease of the plaque volume by 9.9% (p < 0.0001, vs. baseline) was observed; furthermore, a corresponding increase of the serum HDL-C level and decrease of the peripheral blood monocyte count were also seen (12.5%, p < 0.01 and -7.3%, p < 0.0001). In a multivariate regression analysis using the serum lipids and traditional risk factors as the covariates, the increase in the serum HDL-C (β -0.56, p < 0.0001) and the decrease in monocyte count (β 0.23, p = 0.03) were identified as independent predictors of the plaque regression. A model for the prediction of plaque regression according to whether the achieved the change in (Δ) monocyte count and ΔHDL-C were above or below the median values was prepared. Among the four groups, the group with ΔHDL-C ≥8.8% and Δmonocyte count ≤-8.6% showed the largest plaque regression (-20.4%), and the group with ΔHDL-C <8.8% and Δmonocyte count >-8.6% showed the increase of the plaque volume (2.6%). In view of the inflammatory nature of atherosclerosis, the model constructed using the two predictors may be a useful model for the prediction of plaque regression.

Comparison of the effects of nitroprusside versus nicorandil on the slow/no-reflow phenomenon during coronary interventions for acute myocardial infarction

Although slow/no-reflow is a serious problem complicating primary percutaneous coronary interventions (PCI) for acute myocardial infarction (AMI) and is associated with a poor prognosis, its efficacious treatment remains problematic. We compared the acute, in-hospital and long-term (1 year) effects of nitroprusside (NTP) with those of nicorandil (NC) on the slow/no-reflow phenomenon. Forty-nine of 442 consecutive patients with AMI who underwent primary PCI complicated by slow/no-reflow and who received intracoronary NTP (n = 25) or NC (n = 24) administration were studied. Both NTP and NC induced significant improvements in coronary flow, with increases in TIMI flow grade from 1.64 ± 0.62 to 2.74 ± 0.36 (p < 0.001) and 1.60 ± 0.86 to 2.23 ± 0.91 (p < 0.001), and in corrected TIMI frame count from 37.8 ± 15.1 to 13.7 ± 7.1 (p < 0.001) and 30.8 ± 20.7 to 19.3 ± 17.9 (p < 0.001), respectively. The degree of improvement in TIMI flow grade (post-pre/pre) and TIMI frame count (pre-post/pre) showed that NTP was more effective than NC (NTP vs. NC: 0.88 ± 0.79, 0.37 ± 0.37, p = 0.008; 0.59 ± 0.23, 0.36 ± 0.27, p = 0.003, respectively). Congestive heart failure did not tend to last beyond 3 days after onset in the NTP group, which was more than in the NC group, during hospitalization (1/25, 4/24, p = 0.143, respectively). At the 1-year follow-up, the NTP group tended to show more improvement than the NC group in MACE (5/25, 9/24, p = 0.175, respectively). NTP is a more effective treatment for slow/no-reflow associated with PCI in patients with AMI and may improve long-term clinical outcomes compared with NC.