Sex-based association between high-density lipoprotein cholesterol and adverse outcomes after coronary artery bypass grafting

BACKGROUND

High-density lipoprotein cholesterol (HDL-C) is shown to be an independent protective factor against coronary artery diseases (CAD). Yet there are limited studies focusing on the association between HDL-C and coronary artery bypass graft (CABG) surgery outcomes.

HYPOTHESIS

Low levels of HDL-C are associated with higher incidence of adverse outcomes in patients undergoing CABG.

METHODS

This registry-based study included 17,772 patients who underwent elective isolated CABG between 2007 and 2017. Patients were classified into low and desirable HDL-C groups based on their serum HDL-C levels at admission and were followed for one-year post-surgery. The study population included 13,321 patients with low HDL-C and 4,451 with desirable HDL-C. proportional hazard Cox models were performed to evaluate the association between HDL-C levels and incidence of mortality as well as major adverse cardiovascular and cerebrovascular events (MACCE), while adjusting for potential confounders. Moreover, participants were stratified based on sex and the association was also investigated in each subgroup separately.

RESULTS

No significant difference was found between the groups regarding incidence of both mortality and MACCE, after adjusting with Inverse Probability Weighting (IPW) [HR (95%CI): 0.84 (0.46-1.53), p-value:0.575 and HR (95% CI): 0.91 (0.56-1.50), p-value:0.733, respectively]. According to the sex-based subgroup analysis, no significant association was observed after adjustment with IPW analysis. However, as we examined the association between the interaction of HDL-C levels, sex and cardiovascular outcomes, we found a significant association (HR;1.19 (95%CI: 1.04-1.45); p = 0.030).

CONCLUSION

HDL-C level was not associated with either mortality or MACCE during one year after CABG procedure. Sex-based analysis showed that in males, HDL-C is significantly more protective against these outcomes, compared to females. Further studies are necessary to elucidate the exact mechanisms mediating such association.

Gensini score values for predicting periprocedural myocardial infarction: An observational study analysis

The Gensini score (GS) is a convenient, powerful tool for assessing the severity and complexity of coronary artery diseases. Our research investigated the relationship between the GS and periprocedural myocardial infarction (PMI). We recruited 4949 patients (3366 men, 1583 women; mean age 66.45 ± 10.09 years) with a single coronary artery revascularization. Based on the tertile of the GS 20 and 36, the population was divided into 3 groups: Low Group (0 < GS ≤ 20, N = 1809); Intermediate Group (20 < GS ≤ 36, N = 1579); High Group (GS > 36, N = 1561). PMI3 represented the endpoint for cTnI > 3-fold upper reference limit, while PMI5 represented the endpoint for cTnI > 5-fold upper reference limit. The incidence of PMI of High Group was statistically higher than that of Intermediate Group (P < .05), while that of Intermediate Group was statistically higher than Low Group (P < .05). With the adjustment of some general variables, GS was an independent significantly predictor for PMI3 (β = 0.006, P < .05) and PMI5 (β = 0.007, P < .05). Following receiver operating characteristic curve analysis, the optimal cut-off value to predict PMI are 22.5 for PMI3 and 27 for PMI5. The GS was an independent predictor of PMI in the single-coronary revascularization population. Additionally, the 22.5 of GS was the optimal cut-off value for determining the presence of PMI3, while the 27 of GS for PMI5.

Association Between Lipoprotein(a) and Peri-procedural Myocardial Infarction in Patients With Diabetes Mellitus Who Underwent Percutaneous Coronary Intervention

Background

High lipoprotein(a) (Lp[a]) levels are associated with increased risks of cardiovascular events in Percutaneous Coronary Intervention (PCI) patients with diabetes mellitus (DM). Peri-procedural myocardial infarction (PMI) occurs commonly during the PCI, whereas the relationship between Lp(a) and PMI remains unclear. Our study aimed to evaluate the association between Lp(a) value and the incidence of PMI in a larger-scale diabetic cohort undergoing PCI throughout 2013.

Methods

A total of 2,190 consecutive patients with DM were divided into two groups according to the median Lp(a) level of 175 mg/L: Low Lp(a) group (N = 1095) and high Lp(a) group (N = 1095). PMI was defined based on the 2018 universal definition of myocardial infarction.

Results

Patients with high Lp(a) levels exhibited higher rates of PMI compared to those with low Lp(a) levels (2.3% versus 0.8%, P = 0.006). The multivariable logistic analysis showed that PMI was independently predicted by Lp(a) as a dichotomous variable (OR 2.64, 95%CI 1.22-5.70) and as a continuous variable (OR 1.57, 95% CI 1.12-2.20). However, further investigation found that this association was only maintained in men, whose Lp(a) levels were significantly associated with the frequency of PMI, both as a dichotomous variable (OR 3.66, 95%CI 1.34-10.01) and as a continuous variable (OR 1.81, 95%CI 1.18-2.78). Lp(a) wasn't a risk factor of PMI in women.

Conclusions

High Lp(a) levels had forceful correlations with the increased frequency of PMI in male diabetic patients undergoing PCI. Lp(a) might act as a marker of risk stratification and a therapeutic target to reduce PCI-related ischemic events.

Cardiovascular event risk estimated after coronary revascularization and optimal medical therapy: J-ACCESS4 prognostic study

Background

An assessment of cardiac events and survival using quantitative gated myocardial single-photon emission computed tomography (SPECT) (J-ACCESS) associated several risk factors with cardiac events in Japan. The clinical course after revascularization and/or optimal medical therapy (OMT) was followed in patients with coronary artery disease (CAD) at moderate-to-high risk estimated by software incorporating the J-ACCESS risk model. The present study aimed to determine the relevance of changes in estimated risk to outcomes of these therapies.

Methods

This study included 494 patients with possible or definite CAD who underwent initial pharmacological stress ^99mTc-tetrofosmin myocardial perfusion SPECT (MPS) before and eight months after therapy. Major cardiac event risk during 3 years of follow-up was calculated using an equation based on that in the J-ACCESS study. Patients with ≥ 10% cardiac event risk estimated at the first MPS (n = 31) were analyzed and followed up for at least 1 year.

Results

Estimated risk was reduced by ≥ 5% in 14 patients (45%) after therapy. During a follow-up period of 22.1 ± 6.7 months, one patient without such reduction had a major cardiac event. Mean %summed stress scores significantly decreased from baseline to follow-up in patients with and without risk reduction. Left ventricular ejection fraction (LVEF [%]) at rest was significantly increased at the second, compared with the first MPS between patients with, than without risk reduction (57 ± 17 vs. 45 ± 16%, p = 0.001 and 50 ± 11 vs. 49 ± 9%, p = 0.953, respectively).

Conclusions

A reduction in cardiac ischemia and an increase in LVEF by revascularization and/or OMT were necessary to avoid cardiac events among patients with moderate-to-high estimated risk, and changes in event risk were quantifiable.

Hyperlipidaemia and cardioprotection: Animal models for translational studies

Hyperlipidaemia is a well-established risk factor for cardiovascular diseases and therefore, many animal model have been developed to mimic the human abnormal elevation of blood lipid levels. In parallel, extensive research for the alleviation of ischaemia/reperfusion injury has revealed that hyperlipidaemia is a major co-morbidity that attenuates the cardioprotective effect of conditioning strategies (preconditioning, postconditioning and remote conditioning) and that of pharmacological interventions by interfering with cardioprotective signalling pathways. In the present review article, we summarize the existing data on animal models of hypercholesterolaemia (total, low density and HDL abnormalities) and hypertriglyceridaemia used in ischaemia/reperfusion injury and protection from it. We also provide recommendations on preclinical animal models to be used for translations of the cardioprotective strategies into clinical practice. LINKED ARTICLES: This article is part of a themed issue on Risk factors, comorbidities, and comedications in cardioprotection. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.23/issuetoc.

Assessment of the LDL-C/HDL-C ratio as a predictor of one year clinical outcomes in patients with acute coronary syndromes after percutaneous coronary intervention and drug-eluting stent implantation

Background

Despite significant advances in the management of acute coronary syndromes (ACS), there are still plenty of patients undergoing percutaneous coronary intervention (PCI) and stent implantation suffered poor prognosis and high treatment expenditure. Evidence increasingly suggests that the ratio of low-density lipoprotein cholesterol/high-density lipoprotein cholesterol (LDL-C/HDL-C) ratio might be a novel marker for the risk of atherosclerotic cardiovascular disease, but the impact of LDL-C/HDL-C ratio on 1-year prognosis of drug-eluting stent (DES) implantation patients after PCI is still not reported. Our aim of the study was to investigate the impact of LDL-C/HDL-C ratio on 1-year prognosis of DES implantation patients after PCI.

Methods

Between May 2014 and July 2016, 1937 patients who were underwent primary PCI and DES implantation and achieving LDL-C with statins were enrolled and divided into two groups based on the ratio of LDL-C/HDL-C.

Results

The entire occurrence of adverse cardiovascular events according to the ratio of LDL-C/HDL-C showed that there were no significant differences in 1-year cardiovascular death (hazard ratio [HR]: 1.97, 95% confidence interval [CI]: 0.49 to 7.84, P = 0.329), myocardial infarction (MI) (HR: 1.66, 95% CI: 0.84 to 3.28, P = 0.172) and bleeding events (HR: 1.08, 95% CI: 0.83 to 1.41, P = 0.598) The cumulative incidence of target lesion revascularization (TLR) (HR: 1.43, 95% CI: 1.10 to 1.86, P = 0.007), stent thrombosis (ST) (HR: 2.04, 95% CI: 1.06 to 3.93, P = 0.037) and major adverse cardiac events (MACE) (HR: 1.54, 95% CI: 1.24 to 1.91, P <  0.001) were significantly higher in high group than in low group. Multivariate Cox regression analysis revealed that age (HR: 1.556, 95%, CI: 1.198 to 2.021, P <  0.001), together with diabetes mellitus (HR: 1.490, 95% CI: 1.142 to 1.945, P = 0.003), and ratio of LDL-C/HDL-C (HR: 1.638, 95% CI: 1.260 to 2.218, P <  0.001) were independent predictors of 1-year MACE. The Kaplan-Meier cumulative MACE-free survival curves with a log-rank test showed that the presence of high ratio of LDL-C/HDL-C was associated with higher incidences of MACE after PCI with DES implantation.

Conclusions

The high LDL-C/HDL-C ratio was associated with cardiovascular events in patients with ACS after PCI and DES implantation.

Mouse Mast Cell Protease 4 Deletion Protects Heart Function and Survival After Permanent Myocardial Infarction

Chymase, a mast cell serine protease involved in the generation of multiple cardiovascular factors, such as angiotensin II and endothelin-1 (ET-1), is elevated and participates in tissue degeneration after permanent myocardial infarction (PMI). Anesthetized 4-month old male wild-type (WT) C57BL/6J mice and mouse mast cell protease-4 knockout (mMCP-4 KO) congeners were subjected to ligation of the left anterior descending (LAD) coronary artery. A group of mice was then subjected to Kaplan-Meier 28-day survival analysis. In another group of mice, ¹⁸F-fluorodeoxyglucose positron emission tomography (PET) was performed to evaluate heart function and the infarcted zone 3 days post-PMI surgery. Cardiac morphology following PMI was evaluated on formalin-fixed heart slices and glycoproteomic analysis was performed using mass spectrometry. Finally, cardiac and lung tissue content of immunoreactive ET-1 was determined. PMI caused 60% mortality in WT mice, due to left ventricular wall rupture, and 7% in mMCP-4 KO mice. Cardiac PET analysis revealed a significant reduction in left ventricular volume (systolic and diastolic) and preserved the ejection fraction in mMCP-4 KO compared to WT animals. The infarcted area, apoptotic signaling and wall remodeling were significantly decreased in mMCP-4 KO mice compared to their WT congeners, while collagen deposition was increased. Glycoproteomic analysis showed an increase in apolipoprotein A1, an established chymase substrate in mMCP-4 KO mice compared to WT mice post-PMI. ET-1 levels were increased in the lungs of WT, but not mMCP-4 KO mice, 24 h post-PMI. Thus, the genetic deletion of mMCP-4 improved survival and heart function post-PMI.

Impact of high-density lipoprotein 3 cholesterol subfraction on periprocedural myocardial injury in patients who underwent elective percutaneous coronary intervention

Background

Periprocedural myocardial injury (PMI) is a major complication of percutaneous coronary intervention (PCI) and is associated with atherosclerotic coronary plaque and worse clinical outcomes. High-density lipoprotein cholesterol (HDL-C) is a protective factor for cardiovascular disease. However, the role of HDL-C subfractions, such as HDL2 cholesterol (HDL2-C) or HDL3 cholesterol (HDL3-C), in cardiovascular disease remains unclear. The purpose of the study was to investigate the relationship between HDL2-C and HDL3-C subfractions and the incidence of PMI in patients who underwent elective PCI.

Methods

We enrolled 129 patients who underwent elective PCI for stable angina pectoris. PMI was defined as an increase in high-sensitivity troponin T levels > 5 times the upper normal limit (> 0.070 ng/mL) at 24 h after PCI. Serum HDL-C subfractions (HDL2-C and HDL3-C) were assessed using ultracentrifugation in patients with and those without PMI.

Results

HDL3-C levels were significantly lower in patients with PMI than in those without (15.1 ± 3.0 mg/dL vs. 16.4 ± 2.9 mg/dL, p = 0.016) and had an independent and inverse association with PMI (odds ratio, 0.86; 95% confidence interval, 0.74–0.99; p = 0.038). When divided by the cut-off value of HDL3-C for PMI (14.3 mg/dL), the incidence of PMI was significantly higher in low HDL3-C patients than in high HDL3-C patients (51.2% vs. 30.2%, p = 0.020).

Conclusions

HDL3-C was an independent inverse predictor of PMI in patients who underwent elective PCI.

Fractalkine – a local inflammatory marker aggravating platelet activation at the vulnerable plaque

Chemokines play an important role in inducing chemotaxis of cells, piloting white blood cells in immune surveillance and are crucial parts in the development and progression of atherosclerosis. Platelets are mandatory players in the initiation of atherosclerotic lesion formation and are susceptible targets for and producers of chemokines. Several chemokine receptors on platelets have been described previously, amongst them CX3CR1, the receptor for fractalkine. The unique chemokine fractalkine (CX3CL1, FKN) exists as a soluble as well as a membrane-anchored glycoprotein. Its essential role in the formation of atherosclerotic lesions and atherosclerosis progression has been impressively described in mouse models. Moreover, fractalkine induces platelet activation and adhesion via a functional fractalkine receptor (CX3CR1) expressed on the platelet surface. Platelet activation via the FKN/CX3CR1-axis triggers leukocyte adhesion to activated endothelium, and fractalkine-induced platelet P-selectin is mandatory for leukocyte recruitment under arterial flow conditions. This review summarises the role of fractalkine as a potential local inflammatory mediator which influences platelet activation in the setting of atherosclerosis. Beyond that, aspects of a potential interaction between fractalkine and platelet responsiveness to antiplatelet drugs are described. Furthermore, the possible impact of high-density lipoprotein cholesterol (HDL-C) on atherosclerosis progression, platelet activation and fractalkine signalling are discussed.

Early determination of clopidogrel responsiveness by platelet reactivity index identifies patients at risk for cardiovascular events after myocardial infarction

While acute myocardial infarction (MI) is associated with impaired clopidogrel responsiveness, systematic evaluation is lacking due to the inability of functional aggregation-based assays to analyse clopidogrel responsiveness in the presence of glycoprotein IIb/IIIa inhibitors. Using the P2Y12-specific, non-aggregation-based platelet-reactivity-index (PRI) we assessed clopidogrel responsiveness in patients with acute MI. Clopidogrel responsiveness was determined 24 hours (h) after loading with 600 mg clopidogrel in 54 patients with acute MI admitted for coronary intervention. A PRI > 50% was considered as suboptimal inhibition. Overall response in MI patients was suboptimal with a median PRI of 58%. Diabetes, low high-density lipoprotein and pre-hospital clopidogrel loading were associated with impaired clopidogrel responsiveness. Patients loaded at first medical contact had a significantly weaker platelet inhibition by clopidogrel after 24 h (PRI 63%) compared to those loaded peri-interventionally (PRI 54%, p=0.014). Clinical outcome was assessed as a combination of cardiac death, non-fatal MI, stent thrombosis, ischaemic stroke, and urgent target vessel revascularisation after 12 months. The pre-selected cut-off of PRI ≤ 50% yielded a sensitivity of 87% at a specificity of 26%, whereas a PRI ≤ 57% determined by receiver-operating characteristics (ROC)-analysis yielded a sensitivity of 80% at a specificity of 56% (event rate: PRI ≤ 57%: 12.0%; PRI > 57%: 41.4%, p=0.0136). In conclusion, PRI detects clopidogrel responsiveness in acute MI patients requiring glycoprotein IIb/IIIa antagonism; and impaired clopidogrel responsiveness predisposes to clinical events. Pre-hospital clopidogrel loading was associated with impaired response and more adverse events challenging the concept of earliest oral clopidogrel loading in MI patients.

LRP5/canonical Wnt signalling and healing of ischemic myocardium

LRP5 (low-density lipoprotein receptor-related protein 5) activates canonical Wnt signalling. LRP5 plays multiple roles including regulation of lipoprotein and cholesterol homeostasis as well as innate immunity cell function. However, it is not known whether LRP5 has a role in the myocardium. The aim of this study was to investigate LRP5 and Wnt signalling in myocardial remodelling after acute myocardial infarction (MI). Wnt protein levels were determined in a hypercholesterolemic porcine model of MI, in Lrp5 ^-/- C57Bl6 mice, in cultured cardiomyocytes and in human explanted hearts with previous MI episodes. 21 days post-MI, there was upregulation of LRP5 in the ischemic myocardium of hypercholesterolemic pigs as well as an upregulated expression of proteins of the Wnt pathway. We demonstrate via overexpression and silencing experiments that LRP5 induces Wnt pathway activation in isolated cardiomyocytes. Hypoxia and lipid-loading induced the expression of Wnt proteins, whereas this effect is blocked in LRP5-silenced cardiomyocytes. To characterize the function of the LRP5-Wnt axis upregulation in the heart, we induced MI in wild-type and Lrp5 ^-/- mice. Lrp5 ^-/- mice had significantly larger infarcts than Wt mice, indicating a protective role of LRP5 in injured myocardium. The LRP5 upregulation in post-MI hearts seen in pigs and mice was also evident in human hearts as dyslipidemic patients with previous episodes of ischemia have higher expression of LRP5 and Wnt-signalling genes than non-ischemic dilated hearts. We demonstrate an upregulation of LRP5 and the Wnt signalling pathway that it is a prosurvival healing response of cardiomyocytes upon injury.

HDL function is impaired in acute myocardial infarction independent of plasma HDL cholesterol levels

BACKGROUND

High-density lipoproteins (HDLs) protect against the development of atherosclerotic cardiovascular disease. HDL function represents an emerging concept in cardiovascular research.

OBJECTIVE

This study investigated the association between HDL functionality and acute myocardial infarction (MI) independent of HDL-cholesterol plasma levels.

METHODS

Participants (non-ST-segment elevation MI, non-STEMI, n = 41; STEMI, n = 37; non-MI patients, n = 33) from a prospective follow-up study enrolling patients with acute chest pain were matched for age and plasma HDL cholesterol. The in vitro capacity of HDL to (1) mediate cholesterol efflux from macrophage foam cells, (2) prevent low-density lipoprotein oxidation, and (3) inhibit TNF-α-induced vascular adhesion molecule-1 expression in endothelial cells was determined.

RESULTS

STEMI-HDL displayed reduced cholesterol efflux (P < .001) and anti-inflammatory functionality (P = .001), whereas the antioxidative properties were unaltered. Cholesterol efflux correlated with the anti-inflammatory HDL activity (P < .001). Not C-reactive protein levels, a marker of systemic inflammation, but specifically plasma myeloperoxidase levels were independently associated with impaired HDL function (efflux: P = .022; anti-inflammation: P < .001). Subjects in the higher risk quartile of efflux (odds ratio [OR], 5.66; 95% confidence interval [CI], 1.26-25.00; P = .024) as well as anti-inflammatory functionality of HDL (OR, 5.53; 95% CI, 1.83-16.73; P = .002) had a higher OR for MI vs those in the three lower risk quartiles combined.

CONCLUSION

Independent of plasma HDL cholesterol levels, 2 of 3 antiatherogenic HDL functionalities tested were significantly impaired in STEMI patients, namely cholesterol efflux and anti-inflammatory properties. Increased myeloperoxidase levels might represent a major contributing mechanism for decreased HDL functionality in MI patients.

Relationship of non-cardiac biomarkers with periprocedural myocardial injury in patients undergoing percutaneous coronary intervention

percutaneous coronary intervention (PCI) is one of the dominant methods for revascularization in patient with coronary artery disease (CAD), which accompanied with high incidence of periprocedural myocardial injury (PMI) evaluated by postprocedural cardiac biomarker elevation. For the convenience of risk stratification of PMI following PCI, the aim of present review provides a unique opportunity to summarize the relationship of non-cardiac biomarkers with PMI by extensively searching in the MEDLINE to identify all the relevant studies. In conclusion, we found that PCI related PMI might be correlated positively to those non-cardiac biomarkers such as low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol, total cholesterol, triglyceride, the ratios of LDL-C to high-density lipoprotein cholesterol (HDL-C), the ratios of HDL-C to apolipoprotein A-I, the ratio of eicosapentaenoic acid to arachidonic acid, lectin-like oxidized low-density lipoprotein receptor-1, C-reactive protein, high on-treatment platelet reactivity, platelet-monocyte aggregates, N-term pro-B-type natriuretic peptide, hemoglobin and albuminuria. Inversely, no relationships of PMI with those non-cardiac biomarkers such as mean platelet volume, platelet distribution width, platelet-larger cell ratio, uric acid, eosinophils count and the genetic variant of methylenetetrahydrofolate reductase (MTHFR) 677 C>T polymorphism. Moreover, there were controversial associations between PMI and those non-cardiac biomarkers such as high-density lipoprotein cholesterol, glycosylated hemoglobin, homocysteine and the polymorphism Leu33Pro of platelet glycoprotein IIbIIIa. However, almost all studies failed to provide definite mechanism of its findings, and further reaches are needed to focus on the potential mechanisms of association between non-cardiac biomarkers and PMI related to PCI.

High-density lipoprotein cholesterol values independently and inversely predict cardiac troponin T and I concentration

BACKGROUND

This retrospective study was planned to establish potential associations between circulating values of cardiac troponins and those of conventional blood lipids.

METHODS

The study population consisted of patients attending an inpatient clinic of the University Hospital of Verona during the year 2015 as part of routine cardiovascular risk assessment. No exclusion criteria were applied. Serum lipids including total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) were measured using reference enzymatic techniques, whereas troponin T (TnT) was measured using a high-sensitivity (HS) immunoassay. A second analysis was also performed in the General Hospital of Verona, extracting data from the local laboratory database of all patients in whom troponin I (TnI) and blood lipids were simultaneously measured during the same year.

RESULTS

In univariate analysis, HS-TnT was found to be associated with age, sex, TC, LDL-C, HDL-C, but not with TG. In multivariate linear regression analysis, age (positive correlation; P<0.001) and HDL-C (negative correlation; P=0.032) remained significantly associated with HS-TnT. The frequency of HS-TnT values >50 ng/L was higher in subjects with HDL-C <1 mmol/L than in those with HDL-C ≥1 mmol/L [odds ratio (OR), 1.84; 95% confidence interval (CI), 1.03-3.32]. The frequency of HS-TnT values >50 ng/L was also higher in elderly subjects than in younger ones (OR, 2.10; 95% CI, 1.15-3.84). The combination of age and HDL-C explained 35% of overall variability of TnT concentration. In the second analysis, HDL-C was also found to be an independent and negative predictor of TnI in multivariate linear regression analysis (P=0.010). The combination of age and HDL-C explained approximately 28% of the overall variability of TnI concentration.

CONCLUSIONS

Our study suggests that HDL-C values inversely predict cardiac troponins concentration irrespective of age, sex and other blood lipids.

Impact of increased admission lipid levels on periprocedural myocardial injury following an elective percutaneous coronary intervention

OBJECTIVE

Periprocedural myocardial injury (PMI) is known to be a predictor of in-hospital cardiac events and long-term adverse outcomes following a percutaneous coronary intervention (PCI). We aimed to evaluate the correlation between preprocedural serum lipid levels and PMI in patients undergoing elective PCI.

PATIENTS AND METHODS

The final study group included 195 patients (60.1±0.7 years old, 68 women and 127 men). Serum high-sensitive troponin T (hscTnT) concentrations were measured immediately before PCI and 12 h after PCI. Serum total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), and triglyceride (TG) levels were determined immediately before PCI. Serum hscTnT concentrations were adjusted for the clinical and procedural characteristics of the patients using the weighted least-square regression analysis.

RESULTS

The average preprocedural hscTnT concentration was 8.1±0.2 ng/l. The average serum hscTnT concentration increased to 34.1±2.8 ng/l (P<0.001) 12 h after PCI. Postprocedural hscTnT concentrations were correlated positively to serum concentrations of TC (r=0.435; P<0.001), LDL-C (r=0.349; P<0.001), and TG (r=0.517; P<0.001). There was also a positive correlation (r=0.205; P<0.01) between postprocedural hscTnT and lesion length. Mild-moderate PMI (postprocedural hscTnT≥14 to <70 ng/l) and severe PMI (postprocedural hscTnT≥70 ng/l) were observed in 122 (48.7%) and 27 (13.9%) patients, respectively. The patients with severe PMI had higher serum TC (P<0.001), LDL-C (P<0.001), and TG (P<0.001) concentrations.

CONCLUSION

The present study indicates that increased preprocedural TC, LDL-C, and TG serum levels are associated with PMI and its severity following elective PCI.

Meeting report from the 2nd International Symposium on New Frontiers in Cardiovascular Research. Protecting the cardiovascular system from ischemia: between bench and bedside

Recent advances in basic cardiovascular research as well as their translation into the clinical situation were the focus at the last "New Frontiers in Cardiovascular Research meeting". Major topics included the characterization of new targets and procedures in cardioprotection, deciphering new players and inflammatory mechanisms in ischemic heart disease as well as uncovering microRNAs and other biomarkers as versatile and possibly causal factors in cardiovascular pathogenesis. Although a number of pathological situations such as ischemia-reperfusion injury or atherosclerosis can be simulated and manipulated in diverse animal models, also to challenge new drugs for intervention, patient studies are the ultimate litmus test to obtain unequivocal information about the validity of biomedical concepts and their application in the clinics. Thus, the open and bidirectional exchange between bench and bedside is crucial to advance the field of ischemic heart disease with a particular emphasis of understanding long-lasting approaches in cardioprotection.

Preprocedural N-terminal pro-B-type natriuretic peptide as a useful marker for predicting periprocedural myocardial injury following percutaneous coronary intervention in diabetic patients without cardiac dysfunction

BACKGROUND

Elevated preprocedural N-term pro-B-type natriuretic peptide (NT-pro-BNP) and postprocedural cardiac troponin I (cTnI) are related to a poor cardiac outcome in the non-diabetic population. We hypothesized that preprocedural NT-pro-BNP might be a useful marker in predicting periprocedural myocardial injury (PMI) following elective percutaneous coronary intervention (PCI) in type 2 diabetes (T2D).

METHODS

We prospectively enrolled 1194 consecutive diabetic patients with normal cardiac function and preprocedural cTnI who were successfully undergoing elective PCI. Preprocedural NT-pro-BNP levels were assessed at admission, and PMI was evaluated by analysis of cTnI within 24 hours. The relationship between preprocedural NT-pro-BNP levels and the peak values of cTnI after PCI was examined.

RESULTS

Patients with high baseline NT-pro-BNP levels had higher postprocedural cTnI levels (β = 0.123, p < 0.001). In the multivariable model, NT-pro-BNP was associated with higher risk of postprocedural cTnI elevation above 1 × upper limit of normal (ULN, OR, 3.13; 95% CI, 1.51-6.50; p = 0.002), 3 × ULN (OR, 2.44; 95% CI, 1.17-5.08; p = 0.018), 5 × ULN (OR, 3.18; 95% CI, 1.44-7.0; p = 0.004), respectively. Moreover, the incidence of cTnI elevation was higher in patients with the upper tertile of NT-pro-BNP levels than that in ones with the lower tertile of NT-pro-BNP levels (> 1 × ULN: 63.1% vs. 50.0%, p < 0.001; > 3 × ULN: 39.2% vs. 31.9%, p = 0.032; > 5 × ULN: 30.4% vs. 21.9%, p < 0.006; respectively).

CONCLUSIONS

Our data, for the first time, demonstrated that increased preprocedural NT-pro-BNP levels were strongly and independently associated with a higher risk of PMI, suggesting that baseline NT-pro-BNP level might be a useful marker for predicting PMI following PCI in diabetic patients without cardiac dysfunction.

Relationship of high-density lipoprotein cholesterol with periprocedural myocardial injury following elective percutaneous coronary intervention in patients with low-density lipoprotein cholesterol below 70 mg/dL

BACKGROUND

Recent data showed inconsistent association of high-density lipoprotein cholesterol (HDL-C) with cardiovascular risk in patients with different levels of low-density lipoprotein cholesterol (LDL-C) or intensive statin therapy. This study sought to determine the relationship of HDL-C with periprocedural myocardial injury following elective percutaneous coronary intervention (PCI) across a range of LDL-C levels, especially in patients with LDL-C <70 mg/dL.

METHODS AND RESULTS

We enrolled 2529 consecutive patients with normal preprocedural cardiac troponin I (cTnI) who underwent elective PCI. The association between preprocedural HDL-C and periprocedural myocardial injury was evaluated across LDL-C levels, especially in patients with LDL-C <70 mg/dL. The HDL-C level was not predictive of periprocedural myocardial injury across the entire study cohort. However, among patients with LDL-C <70 mg/dL, a 1 mg/dL increase in HDL-C was associated with a 3% reduced risk for postprocedural cTnI above 1×upper limit of normal (ULN) (odds ratio: 0.97; 95% CI: 0.95 to 0.99; P=0.004), a 3% reduced risk for postprocedural cTnI above 3×ULN odds ratio: 0.97; 95% CI: 0.95 to 0.99; P=0.022), and a 3% reduced risk for postprocedural cTnI above 5×ULN (odds ratio: 0.97; 95% CI: 0.95 to 0.99; P=0.017). The relation between plasma HDL-C level and risk of postprocedural cTnI elevation above 1×ULN, 3×ULN, and 5×ULN was modified by LDL-C level (all P for interaction <0.05).

CONCLUSIONS

Higher HDL-C levels were associated with reduced risk of periprocedural myocardial injury only in patients with LDL-C <70 mg/dL.

Epidemiology: disease associations and modulators of HDL-related biomarkers

Epidemiological studies have shown an inverse association between high-density lipoprotein cholesterol (HDL-C) levels and risk of ischemic heart disease. In addition, a low level of HDL-C has been shown to be a risk factor for other diseases not related to atherosclerosis. However, recent studies have not supported a causal effect of HDL-C in the development of atherosclerosis. Furthermore, new drugs markedly elevating HDL-C levels have been disappointing with respect to clinical endpoints. Earlier, most studies have focused almost exclusively on the total HDL-C without regard to the chemical composition or multiple subclasses of HDL particles. Recently, there have been efforts to dissect the HDL fraction into as many well-defined subfractions and individual molecules of HDL particles as possible. On the other hand, the focus is shifting from the structure and composition to the function of HDL particles. Biomarkers and mechanisms that could potentially explain the beneficial characteristics of HDL particles unrelated to their cholesterol content have been sought with sophisticated methods such as proteomics, lipidomics, metabonomics, and function studies including efflux capacity. These new approaches have been used in order to resolve the complex effects of diseases, conditions, environmental factors, and genes in relation to the protective role of HDL but high-throughput methods are still needed for large-scale epidemiological studies.

Beginning to understand high-density lipoproteins

This article reconciles the classic view of high-density lipoproteins (HDL) associated with low risk for cardiovascular disease (CVD) with recent data (genetics studies and randomized clinical trials) casting doubt over the widely accepted beneficial role of HDL regarding CVD risk. Although HDL cholesterol has been used as a surrogate measure to investigate HDL function, the cholesterol content in HDL particles is not an indicator of the atheroprotective properties of HDL. Thus, more precise measures of HDL metabolism are needed to reflect and account for the beneficial effects of HDL particles. Current and emerging therapies targeting HDL are discussed.

Non-HDL cholesterol is a better target for predicting periprocedural myocardial injury following percutaneous coronary intervention in type 2 diabetes

OBJECTIVE

Non-HDL cholesterol (non-HDL-C) has recently been recommended as a first target for dyslipidemia management. We previously reported that LDL cholesterol (LDL-C) and non-HDL-C levels were similarly associated with periprocedural myocardial injury (PMI) following percutaneous coronary intervention (PCI) in patients with coronary artery disease. Here we investigated the comparative prognostic value of non-HDL-C and LDL-C for PMI following PCI in type 2 diabetes (T2D).

METHODS

We prospectively enrolled 1194 consecutive T2D patients with normal preprocedural cTnI undergoing PCI. Patients were divided into the two groups: group A [glycated hemoglobin (HbA1c) < 7%, n = 567] and group B (HbA1c ≥ 7%, n = 627). PMI was evaluated by cTnI analysis within 24 h. The relationship of preprocedural non-HDL-C and LDL-C levels with peak cTnI values after PCI was examined.

RESULTS

Patients in group B, with higher preprocedural non-HDL-C levels, had higher postprocedural cTnI levels (β = 0.102, P = 0.011). In the multivariable model, a 1-SD increase in non-HDL-C produced a 30% and 33% increased risk of postprocedural cTnI >3 × upper limit of normal (ULN) and >5 × ULN in group B, respectively. However, neither LDL-C nor group A patients were affected. Furthermore, patients with non-HDL-C levels ≥ 130 mg/dl compared with non-HDL-C levels ≤ 100 mg/dl were associated with a 83.3% and 71.7% increased risk of postprocedural cTnI >3 × ULN and >5 × ULN in group B, respectively.

CONCLUSIONS

In poorly-controlled diabetic patients (HbA1c ≥ 7%) undergoing PCI, non-HDL-C but not LDL-C was independently associated with and increased risk of PMI, and non-HDL-C levels ≥ 130 mg/dl had a worse PMI risk profile compared with non-HDL-C levels <100 mg/dl.

The ratio of high-density lipoprotein cholesterol to apolipoprotein A-I predicts myocardial injury following elective percutaneous coronary intervention

BACKGROUND

High-density lipoprotein (HDL) has cardioprotective properties. Each HDL particle has a few molecules of apolipoprotein A-I (apoA-I) and carries various amounts of cholesterol. The ratio of high-density lipoprotein cholesterol (HDL-C) to apoA-I may reflect mean HDL particle size.

HYPOTHESIS

HDL-C/apoA-I ratio may provide more information than HDL-C and apoA-I in predicting myocardial injury following elective percutaneous coronary intervention (PCI).

METHODS

We prospectively enrolled 2529 consecutive patients who underwent elective PCI and assessed the relationships of preprocedural HDL-C, apoA-I, and their ratio with peak cardiac troponin I (cTnI) within 24 hours after PCI.

RESULTS

Neither HDL-C nor apoA-I levels showed significant association with postprocedural cTnI elevation, whereas HDL-C/apoA-I ratio was associated with postprocedural cTnI elevation above 3 up to 30 × upper limit of normal (ULN), with the lowest risk in the middle quintile (all P values for quadratic term were <0.05). Adjusted odds ratios (95% confidence interval) of postprocedural cTnI >3 × ULN for quintile 1 to 5 of HDL-C/apoA-I ratio were: 1 (reference), 0.81 (0.62-1.07), 0.57 (0.43-0.75), 0.65 (0.49-0.85), and 0.76 (0.58-1.01), respectively, and the adjusted odds ratios of postprocedural cTnI >30 × ULN for quintile 1 to 5 of HDL-C/apoA-I ratio were: 1 (reference), 0.81 (0.49-1.361), 0.42 (0.23-0.77), 0.66 (0.38-1.14), and 0.82 (0.49-1.38), respectively.

CONCLUSIONS

There was a U-shaped association between HDL-C/apoA-I ratio and myocardial injury following PCI.

Intravascular ultrasound analysis to determine the relationship between high-density lipoprotein cholesterol and lesion characteristics in patients with coronary artery disease

OBJECTIVES

This study utilized grayscale intravascular ultrasound (IVUS) to explore the relationship between high-density lipoprotein cholesterol (HDL-C) levels and culprit lesion characteristics in patients with coronary artery disease.

BACKGROUND

Low HDL-C is associated with an increased risk of cardiovascular events. Previous IVUS studies have suggested a significant association between lesion characteristics and cardiovascular events.

METHODS

According to HDL-C levels, 120 patients who underwent IVUS for native, de novo coronary lesions before any intervention were divided into a low HDL-C group (<40 mg/dL, n = 60) and a high HDL-C group (≥40 mg/dL, n = 60). Quantitative and qualitative IVUS analyses were performed to compare lesion characteristics.

RESULTS

Quantitative IVUS measurements showed no significant differences between the 2 groups. HDL-C level was not significantly correlated with remodeling index (r = 0.03, P = 0.78). However, attenuated plaque was more frequent in the low HDL-C group (48.3% vs. 28.3%, P = 0.02) and a greater percentage of attenuated plaque was found in this group (32.5 ± 21.3% vs. 21.0 ± 11.0%, P = 0.02). Moreover, when categorized into 4 groups according to HDL-C levels, the proportion of attenuated plaque (64.7% in group with <30 mg/dL, 41.9% in group with 30-39 mg/dL, 36.4% in group with 40-59 mg/dL, and 6.3% in group with ≥60 mg/dL; P = 0.001 for trend) was significantly different among groups. On multivariate analysis, only HDL-C and male gender were independently associated with the presence of attenuated plaque at the culprit lesions.

CONCLUSIONS

Patients with low levels of HDL-C may be at increased risk of having a higher incidence of attenuated plaques.

Relation of admission high-density lipoprotein cholesterol level and in-hospital mortality in patients with acute non-ST segment elevation myocardial infarction (from the National Cardiovascular Data Registry)

Despite recent therapeutic advances, significant residual risk for in-hospital mortality persists among patients admitted with acute myocardial infarction (MI). Low levels of high-density lipoprotein cholesterol (HDL-C), a known independent predictor of increased cardiovascular events, may be an important modulator of heightened risk after acute MI. We evaluated admission HDL-C levels among 98,276 patients with non-ST elevation myocardial infarction with acute MI from the Acute Coronary Treatment and Intervention Outcomes Network Registry-Get With the Guidelines (ACTION Registry-GWTG) program who were enrolled from 490 United States hospitals from January 2007 to December 2010. Clinical characteristics, treatments, atherosclerotic burden, and in-hospital outcomes were analyzed by quartiles of admission HDL-C (Q1: 10 to 30 mg/dl; Q2: 30.1 to 36.9 mg/dl; Q3: 37 to 45 mg/dl; and Q4: 45.1 to 100 mg/dl). Logistic regression was used to explore the relation among HDL-C quartiles, coronary artery disease severity, and in-hospital mortality. Almost half of the patients with acute MI had low admission levels of HDL-C (less than the median 36.9 mg/dl). Such patients were younger, more often men, white, obese, diabetic, smokers, and had higher rates of previous cardiovascular events. After multivariate adjustment, patients with low HDL-C levels had greater extent of severe angiographic multivessel coronary narrowings and higher mortality. Among the 26% of patients in the lowest HDL-C quartile (≤30 mg/dl), there was a 16% greater risk of in-hospital mortality compared with patients in the highest HDL-C quartile (p = 0.012). In conclusion, low levels of HDL-C were common in patients admitted with acute MI and were associated with more extensive angiographic coronary disease. Very low levels of admission HDL-C were observed in one-quarter of patients and associated with significantly higher in-hospital mortality.

Predictors of coronary intervention-related myocardial infarction in stable angina patients pre-treated with statins

INTRODUCTION

Peri-procedural myocardial infarction (PMI) is a frequent and prognostically important complication of percutaneous coronary intervention (PCI). This study was designed to determine the predictors of PMI in patients pre-treated with statins.

MATERIAL AND METHODS

A total of 418 stable angina pectoris patients taking statins and aspirin were included. All the patients underwent PCI. Serum concentrations of creatine kinase (CK-MB mass) and troponin I (TnI) were measured prior to and then within 16 to 24 hours after PCI. The incidence of PMI was assessed using the established criteria (≥ 3 times upper limit of normal).

RESULTS

Four hundred and eighteen stable patients (63 ±10 years, 68% males) were treated by PCI. The technical success rate of PCI was 99%. The incidence of PMI based on CK-MB mass or TnI release was 12% (PMI group). There were no significant differences in baseline clinical and procedural characteristics between PMI and non-PMI groups except for the balloon inflation time (40 ±44 s vs. 26 ±27 s; p = 0.02) and the proportion of treated type C lesions (42% vs. 28%; p = 0.03). In multivariate analysis, the independent predictors of PMI were balloon inflation time (OR = 1.01; 95% CI 1.001-1.020; p = 0.02) and pre-procedural level of C-reactive protein (OR = 1.38; 95% CI 1.059-1.808; p = 0.02).

CONCLUSIONS

These results suggest that C-reactive protein and balloon ischaemic time are independent predictors of PMI in stable angina patients pre-treated with statins.

Statin loading before percutaneous coronary intervention: proposed mechanisms and applications

Statin therapy reduces the risk of cardiovascular events in patients with coronary artery disease. Recent in vitro and in vivo studies demonstrated a LDL-independent action of these class of drugs, which appears in modulating endothelial function, inflammation and thrombosis. Periprocedural myocardial infarction and contrast-induced nephropathy after percutaneous coronary intervention (PCI), associated with worse outcome on long-term follow-up, are both complications related to inflammatory pathogenetic mechanisms. Randomized studies demonstrated a beneficial effect of short-term statin pretreatment in reducing periprocedural cardiac marker release in patients undergoing PCI. Statin therapy before elective PCI reduces periprocedural myocardial infarction in patients with stable angina. Furthermore, an acute loading with a high dose of atorvastatin prevents myocardial damage in patients with acute coronary syndromes undergoing early PCI (<48 h). In patients already on chronic statin therapy, a reload with high-dose statins was associated with a significant improvement on 30-day major adverse cardiac event rates. Furthermore, statin therapy at the time of PCI significantly decreased the incidence of contrast-induced nephropathy. This evidence suggests an ‘upstream administration’ of short-term, high-dose statins in all patients undergoing PCI.

Coronary microembolization: from bedside to bench and back to bedside

Coronary microembolization from the erosion or rupture of a vulnerable atherosclerotic plaque occurs spontaneously in acute coronary syndromes and iatrogenically during percutaneous coronary interventions. Typical consequences of coronary microembolization are microinfarcts with an inflammatory response, contractile dysfunction, and reduced coronary reserve. Apart from transient elevations of creatine kinase and troponin, microemboli can be visualized by intracoronary Doppler and the resulting microinfarcts by late-enhancement nuclear magnetic resonance. Statins, antiplatelet agents, and coronary vasodilators protect against microembolization and microinfarction when started before percutaneous coronary interventions. Distal protection devices can retrieve atherothrombotic debris and prevent its embolization into the microcirculation, but their effect on clinical outcome has been disappointing so far, except for saphenous vein bypass grafts. Devices for aspiration of thrombi and thrombus-derived vasoconstrictor, thrombogenic, and inflammatory substances, however, reduce thrombus burden, improve perfusion, and provide protection in patients with acute myocardial infarction.