Cardioprotective actions of acute HMG-CoA reductase inhibition in the setting of myocardial infarction

Comparison of cardiocerebrovascular disease incidence between angiotensin converting enzyme inhibitor and angiotensin receptor blocker users in a real-world cohort

BACKGROUND

Both angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) are known to be effective in managing cardiovascular diseases, but more evidence supports the use of an ACEI. This study investigated the difference in cardiovascular disease incidence between relatively low-compliance ACEIs and high-compliance ARBs in the clinical setting.

METHODS

Patients who were first prescribed ACEIs or ARBs at two tertiary university hospitals in Korea were observed in this retrospective cohort study for the incidence of heart failure, angina, acute myocardial infarction, cerebrovascular disease, ischemic heart disease, and major adverse cardiovascular events for 5 years after the first prescription. Additionally, 5-year Kaplan-Meier survival curves were used based on the presence or absence of statins.

RESULTS

Overall, 2,945 and 9,189 patients were prescribed ACEIs and ARBs, respectively. When compared to ACEIs, the incidence of heart failure decreased by 52% in those taking ARBs (HR [95% CI] = 0.48 [0.39-0.60], P < 0.001), and the incidence of cerebrovascular disease increased by 62% (HR [95% CI] = 1.62 [1.26-2.07], P < 0.001). The incidence of ischemic heart disease (P = 0.223) and major adverse cardiovascular events (P = 0.374) did not differ significantly between the two groups.

CONCLUSIONS

ARBs were not inferior to ACEIs in relation to reducing the incidence of cardiocerebrovascular disease in the clinical setting; however, there were slight differences for each disease. The greatest strength of real-world evidence is that it allows the follow-up of specific drug use, including drug compliance. Large-scale studies on the effects of relatively low-compliance ACEIs and high-compliance ARBs on cardiocerebrovascular disease are warranted in the future.

Rosuvastatin for Reduction of Myocardial Damage during Coronary Angioplasty - the Remedy Trial

BACKGROUND

Periprocedural myocardial infarction (MI) is a frequent complication of percutaneous coronary intervention (PCI). Statins might reduce its incidence. The aims of the present study are to assess whether such benefit is a class-effect or whether differences exist between various lipid-lowering strategies and whether cardioprotection is exerted by increasing circulating endothelial progenitor cells (EPCs).

METHODS

The REMEDY study will enroll a total of 1080 patients submitted to elective PCI. Eligible patients will be randomized into 4 groups: 1) placebo; 2) atorvastatin (80 mg + 40 mg before PCI); 3) rosuvastatin (40 mg twice before PCI); and 4) rosuvastatin (5 mg) and ezetimibe (10 mg) twice before PCI. Peri-procedural MI is defined as an elevation of markers of cardiac injury (either CK-MB or troponin I or T) values >5x the upper reference limit estimated at the 99th percentile of the normal distribution, or a rise >20 % in case of baseline values already elevated. EPCs will be assessed before, at 24 h and - in a subset of diabetic patients - at 3 months after PCI (EPC-substudies). The primary endpoint of the main REMEDY study is the rate of peri-procedural MI in each of the 4 treatment arms. Secondary endpoints are the combined occurrence of 1-month major adverse events (MACE, including death, MI, or the need for unplanned revascularization); and any post-procedural increase in serum creatinine. Endpoints of the EPC-substudies are the impact of tested regimens on 1) early (24-h) and 3-month EPC levels and functional activity; 2) stent strut re-endothelialization and neointimal hyperplasia; 3) 1-year MACE. REMEDY will add important information on the cardioprotective effects of statins after PCI.

Role of phosphatase activity of soluble epoxide hydrolase in regulating simvastatin-activated endothelial nitric oxide synthase

Soluble epoxide hydrolase (sEH) has C-terminal epoxide hydrolase and N-terminal lipid phosphatase activity. Its hydrolase activity is associated with endothelial nitric oxide synthase (eNOS) dysfunction. However, little is known about the role of sEH phosphatase in regulating eNOS activity. Simvastatin, a clinical lipid-lowering drug, also has a pleiotropic effect on eNOS activation. However, whether sEH phosphatase is involved in simvastatin-activated eNOS activity remains elusive. We investigated the role of sEH phosphatase activity in simvastatin-mediated activation of eNOS in endothelial cells (ECs). Simvastain increased the phosphatase activity of sEH, which was diminished by pharmacological inhibitors of sEH phosphatase. In addition, pharmacological inhibition of sEH phosphatase or overexpressing the inactive phosphatase domain of sEH enhanced simvastatin-induced NO bioavailability, tube formation and phosphorylation of eNOS, Akt, and AMP-activated protein kinase (AMPK). In contrast, overexpressing the phosphatase domain of sEH limited the simvastatin-increased NO biosynthesis and eNOS phosphorylation at Ser1179. Simvastatin evoked epidermal growth factor receptor–c-Src–increased Tyr phosphorylation of sEH and formation of an sEH–Akt–AMPK–eNOS complex, which was abolished by the c-Src kinase inhibitor PP1 or c-Src dominant-negative mutant K298M. These findings suggest that sEH phosphatase activity negatively regulates simvastatin-activated eNOS by impeding the Akt–AMPK–eNOS signaling cascade.

Atorvastatin at reperfusion reduces myocardial infarct size in mice by activating eNOS in bone marrow-derived cells

Background

The current study was designed to test our hypothesis that atorvastatin could reduce infarct size in intact mice by activating eNOS, specifically the eNOS in bone marrow-derived cells. C57BL/6J mice (B6) and congenic eNOS knockout (KO) mice underwent 45 min LAD occlusion and 60 min reperfusion. Chimeric mice, created by bone marrow transplantation between B6 and eNOS KO mice, underwent 40 min LAD occlusion and 60 min reperfusion. Mice were treated either with vehicle or atorvastatin in 5% ethanol at a dose of 10 mg/kg IV 5 min before initiating reperfusion. Infarct size was evaluated by TTC and Phthalo blue staining.

Results

Atorvastatin treatment reduced infarct size in B6 mice by 19% (p<0.05). In eNOS KO vehicle-control mice, infarct size was comparable to that of B6 vehicle-control mice (p = NS). Atorvastatin treatment had no effect on infarct size in eNOS KO mice (p = NS). In chimeras, atorvastatin significantly reduced infarct size in B6/B6 (donor/recipient) mice and B6/KO mice (p<0.05), but not in KO/KO mice or KO/B6 mice (p = NS).

Conclusions

The results demonstrate that acute administration of atorvastatin significantly reduces myocardial ischemia/reperfusion injury in an eNOS-dependent manner, probably through the post-transcriptional activation of eNOS in bone marrow-derived cells.

MicroRNA-539 is up-regulated in failing heart, and suppresses O-GlcNAcase expression

Derangements in metabolism and related signaling pathways characterize the failing heart. One such signal, O-linked β-N-acetylglucosamine (O-GlcNAc), is an essential post-translational modification regulated by two enzymes, O-GlcNAc transferase and O-GlcNAcase (OGA), which modulate the function of many nuclear and cytoplasmic proteins. We recently reported reduced OGA expression in the failing heart, which is consistent with the pro-adaptive role of increased O-GlcNAcylation during heart failure; however, molecular mechanisms regulating these enzymes during heart failure remain unknown. Using miRNA microarray analysis, we observed acute and chronic changes in expression of several miRNAs. Here, we focused on miR-539 because it was predicted to target OGA mRNA. Indeed, co-transfection of the OGA-3'UTR containing reporter plasmid and miR-539 overexpression plasmid significantly reduced reporter activity. Overexpression of miR-539 in neonatal rat cardiomyocytes significantly suppressed OGA expression and consequently increased O-GlcNAcylation; conversely, the miR-539 inhibitor rescued OGA protein expression and restored O-GlcNAcylation. In conclusion, this work identifies the first target of miR-539 in the heart and the first miRNA that regulates OGA. Manipulation of miR-539 may represent a novel therapeutic target in the treatment of heart failure and other metabolic diseases.

High fat feeding in mice is insufficient to induce cardiac dysfunction and does not exacerbate heart failure

Preclinical studies of animals with risk factors, and how those risk factors contribute to the development of cardiovascular disease and cardiac dysfunction, are clearly needed. One such approach is to feed mice a diet rich in fat (i.e. 60%). Here, we determined whether a high fat diet was sufficient to induce cardiac dysfunction in mice. We subjected mice to two different high fat diets (lard or milk as fat source) and followed them for over six months and found no significant decrement in cardiac function (via echocardiography), despite robust adiposity and impaired glucose disposal. We next determined whether antecedent and concomitant exposure to high fat diet (lard) altered the murine heart's response to infarct-induced heart failure; high fat feeding during, or before and during, heart failure did not significantly exacerbate cardiac dysfunction. Given the lack of a robust effect on cardiac dysfunction with high fat feeding, we then examined a commonly used mouse model of overt diabetes, hyperglycemia, and obesity (db/db mice). db/db mice (or STZ treated wild-type mice) subjected to pressure overload exhibited no significant exacerbation of cardiac dysfunction; however, ischemia-reperfusion injury significantly depressed cardiac function in db/db mice compared to their non-diabetic littermates. Thus, we were able to document a negative influence of a risk factor in a relevant cardiovascular disease model; however, this did not involve exposure to a high fat diet. High fat diet, obesity, or hyperglycemia does not necessarily induce cardiac dysfunction in mice. Although many investigators use such diabetes/obesity models to understand cardiac defects related to risk factors, this study, along with those from several other groups, serves as a cautionary note regarding the use of murine models of diabetes and obesity in the context of heart failure.

Impact of long-term statin therapy on postprocedural myocardial infarction in patients undergoing nonemergency percutaneous coronary intervention

Periprocedural statin therapy has been shown to decrease the rate of myocardial infarctions (MIs) after percutaneous coronary intervention (PCI). However, the impact of long-term statin therapy on postprocedure MI remains unknown. We examined the impact of long-term statin therapy on cardiac enzyme (cardiac troponin I [cTnI] and creatine kinase-MB [CK-MB]) increases after PCI in patients undergoing nonemergency PCI. Using the 2004/2005 Cornell Angioplasty Registry, we evaluated 1,482 patients undergoing elective or urgent PCI with normal preprocedure cardiac enzymes levels (cTnI and CK-MB). The population was divided into 2 groups: (1) patients on long-term (≥7 days) statin therapy before PCI (n = 1,073) and (2) patients not on long-term statin regimen (n = 409). Cardiac enzyme levels after PCI were assessed at 8, 12, and 18 hours after PCI. An increase in cTnI ≥1 time upper-limit of normal (ULN) was observed in 830 patients (56.1%) and an increase in cTnI ≥3 times ULN was observed in 518 patients (35.0%). There was no difference in incidence of cTnI increases ≥3 times ULN in patients on long-term statin therapy versus those not on long-term statin therapy in the overall group (35.1% vs 34.5%, p = 0.855). There was a trend toward a lower incidence of small cTnI increases ≥1 time ULN in patients on long-term statin therapy versus those not receiving long-term statins (54.6% vs 59.7%, p = 0.090). Incidence of CK-MB increases ≥1 time or ≥3 times ULN and peak cTnI and CK-MB levels were similar between the 2 groups. In a subgroup of patients with unstable angina, long-term statin therapy decreased small cTnI increases (≥1 time ULN) after PCI (54.6% vs 64.3%, p = 0.023). The greatest benefit in decrease of MIs after PCI was seen in patients with unstable angina receiving long-term high-dose statin therapy. In conclusion, long-term statin therapy did not decrease the incidence of periprocedural MI in patients with stable coronary artery disease undergoing nonemergency PCI. In patients with unstable coronary syndromes, long-term statin therapy may be beneficial, particularly at a high dose.

The effect of acute administration of statins on coronary microcirculation during the pre-revascularization period in patients with myocardial infraction

The beneficial effects of statin pretreatment as well as of staccato reperfusion (SR) on myocardium have been demonstrated in patients undergoing cardiac interventions. In this study, we compared the effects of the acute statin administration prior to percutaneous coronary intervention (PCI) with the effects of staccato or abrupt reperfusion on coronary microcirculation in patients with myocardial infarction (MI).

METHODS

We randomly assigned 47 patients who had ST-elevation or non-ST-elevation MI 48 h prior to PCI, into three groups: staccato reperfusion (consisting of 6 periods of 10-s balloon inflation/deflation) plus statin therapy (SRSG), statin therapy plus abrupt reperfusion (SG), and abrupt reperfusion alone (ARG). Myocardial contrast echocardiography (MCE) was performed to assess the blood volume (A), velocity (β) and flow (A × β) of the segments associated with the PCI-treated artery the day following intervention and 30 days after. LV end-diastolic (EDV) and systolic volumes (ESVs), wall motion score index (WMSI) were evaluated.

RESULTS

Compared to ARG, SRSG and SG resulted in a greater improvement in A, β and A × β (F = 20.6, p < 0.001 for A, F = 3.5, p = 0.03 for β and F = 11.3, p < 0.001 for A × β for the overall effect of intervention) as well as a greater decrease of WMSI, EDV and ESV (p < 0.01) one month post-PCI. The changes of all echocardiography markers were greater in SRSG than SG (p < 0.01). The % changes in ESV correlated with the corresponding % changes in MCE indices in SRSG and SG (p < 0.05).

CONCLUSION

The acute statin administration prior to reperfusion either alone or in synergy with staccato reperfusion ameliorates coronary microcirculatory dysfunction in patients with myocardial infarction.

Effect of statins pretreatment on periprocedural myocardial infarction in patients undergoing percutaneous coronary intervention: a meta-analysis

BACKGROUND

Periprocedural myocardial injury remains the most common complication associated with percutaneous coronary intervention (PCI). Previous studies have demonstrated that even a small elevation of cardiac enzymes is associated with higher risk of mortality during follow-up.

OBJECTIVE

We performed a meta-analysis based on all currently available randomized controlled trials (RCT) to evaluate the beneficial effects of hydroxymethylglutaryl-CoA reductase inhibitors (statins) given before PCI on preventing periprocedural myocardial infarction (MI).

METHODS

The published literature was scanned by formal searches of electronic databases (PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials) and conference proceedings up through August 2009. RCTs were eligible for inclusion if they compared preprocedural statins versus placebo treatment in patients not taking statins previously but scheduled for PCI and had the data of periprocedural MI reported by the trial investigators.

RESULTS

Prespecified criteria were met by 6 RCTs involving 2,088 patients. During the periprocedural period, 81 of 1,051 patients (7.7%) in the statins pretreatment group developed periprocedural MI, significantly less than 147 of 1,037 (14.2%) patients assigned to the control group (OR 0.51, 95% CI 0.38-0.67; P< 0.001). During 1-month follow-up, only 4 deaths, 7 non-periprocedural Q-wave MIs, and 4 revascularizations occurred in all 2,088 enrolled patients. The composite of death, MI, or target vessel revascularization at 1 month, essentially driven by periprocedural MI, was reported in 8.0% in the statins pretreatment group and 15.3% in the control group (OR 0.48, 95% CI 0.36-0.64; P< 0.001).

CONCLUSIONS

This meta-analysis supports the effectiveness of statins pretreatment on reducing the rate of periprocedural MI in patients undergoing PCI.

Predictive value of C-reactive protein after drug-eluting stent implantation

During the last few decades, with the evolution of techniques and materials and the increasing experience of operators, percutaneous coronary interventions (PCI) have become an equally efficient alternative to coronary artery bypass grafts for the treatment of most coronary stenoses. Bare-metal stent implantation represented a major step forward, compared with plain old balloon angioplasty (POBA), by improving the immediate angiographic success. However, the incidence of in-stent restenosis (ISR) remained unacceptably high. Development of the drug-eluting stent (DES) significantly improved the outcome of PCI by dramatically abating the rate of ISR and reducing the incidence of target lesion revascularization. However, ISR has not been eliminated and the persistence of metal vessel scaffolding also raises concern regarding the occurrence of late or very late stent thrombosis. POBA and stent implantation have been shown to induce a local and systemic inflammatory response, whose magnitude is associated with worse clinical outcome, and they increase the risk of ISR. C-reactive protein, a marker of systemic inflammation, has been demonstrated to predict clinical and angiographic outcome after POBA or bare-metal stent implantation. However, conflicting data regarding the prognostic value of C-reactive protein following DES implantation are available. In this paper, we review the literature regarding the clinical and pathophysiological association between inflammation and prognosis after DES implantation and suggest some possible therapeutic approaches to reduce inflammatory burden with the aim to improve clinical and angiographic outcome after PCI.

Cardioprotection by N-acetylglucosamine linkage to cellular proteins

BACKGROUND

The modification of proteins with O-linked beta-N-acetylglucosamine (O-GlcNAc) represents a key posttranslational modification that modulates cellular function. Previous data suggest that O-GlcNAc may act as an intracellular metabolic or stress sensor, linking glucose metabolism to cellular function. Considering this, we hypothesized that augmentation of O-GlcNAc levels represents an endogenously recruitable mechanism of cardioprotection.

METHODS AND RESULTS

In mouse hearts subjected to in vivo ischemic preconditioning, O-GlcNAc levels were significantly elevated. Pharmacological augmentation of O-GlcNAc levels in vivo was sufficient to reduce myocardial infarct size. We investigated the influence of O-GlcNAc levels on cardiac injury at the cellular level. Lethal oxidant stress of cardiac myocytes produced a time-dependent loss of cellular O-GlcNAc levels. This pathological response was largely reversible by pharmacological augmentation of O-GlcNAc levels and was associated with improved cardiac myocyte survival. The diminution of O-GlcNAc levels occurred synchronously with the loss of mitochondrial membrane potential in isolated cardiac myocytes. Pharmacological enhancement of O-GlcNAc levels attenuated the loss of mitochondrial membrane potential. Proteomic analysis identified voltage-dependent anion channel as a potential target of O-GlcNAc modification. Mitochondria isolated from adult mouse hearts with elevated O-GlcNAc levels had more O-GlcNAc-modified voltage-dependent anion channel and were more resistant to calcium-induced swelling than cardiac mitochondria from vehicle mice.

CONCLUSIONS

O-GlcNAc signaling represents a unique endogenously recruitable mechanism of cardioprotection that may involve direct modification of mitochondrial proteins critical for survival such as voltage-dependent anion channel.

Randomized Trial of Statin Administration for Myocardial Injury

BACKGROUND

Minor myocardial damage after percutaneous coronary intervention (PCI) is associated with cardiac risks, which statins seem to reduce. The aim of this study was to examine whether intensive lipid-lowering therapy is more effective in decreasing the risk of cardiac injury after PCI than moderate lipid-lowering therapy.

METHODS AND RESULTS

Subjects comprised 42 patients with stable angina without previous statin treatment, randomly assigned to either an intensive lipid-lowering group (Group A: target low-density lipoprotein-cholesterol (LDL-C)<70 mg/dl) or a moderate lipid-lowering group (Group B: target LDL-C<100 mg/dl) 2 weeks before PCI. All patients took statins to reach target LDL-C levels. Incidence of periprocedural myocardial injury was assessed by analyzing levels of creatine kinase myocardial isozyme (CK-MB) and cardiac troponin T (TnT) before and 6, 12 and 24 h after PCI. Minor myocardial damage was defined as TnT elevation to >0.01 ng/ml. Frequency of minor myocardial damage was 14.2% in Group A and 47.6% in Group B (p=0.043). CK-MB was above the upper limit of normal (ULN) in 19% of Group A and 33.3% of Group B (p=0.44), and CK-MB was >3x ULN in 9.5% of Group A and 19% of Group B (p=0.66).

CONCLUSIONS

Intensive lipid-lowering therapy before PCI reduces minor myocardial damage during PCI with stenting compared with moderate lipid-lowering therapy.

Effects of receipt of chronic statin therapy before the onset of acute myocardial infarction: A retrospective study in patients undergoing primary percutaneous coronary intervention

BACKGROUND

Studies have reported an association between receipt of statin therapy and a reduction in complications after elective percutaneous coronary intervention (PCI). However, there are limited data on the effects of chronic statin therapy before the occurrence of an acute myocardial infarction (AMI).

OBJECTIVE

This study investigated whether administration of chronic statin therapy before AMI was associated with a reduction in reperfusion injury in AMI patients undergoing PCI.

METHODS

This was a retrospective study of consecutive patients with a first AMI who underwent successful reperfusion therapy with PCI within 24 hours after the onset of AMI between April 1998 and October 2003. Patients were stratified according to whether they had or had not been receiving chronic statin therapy for > or = 1 month before the onset of AMI. The following end points were compared after PCI: electrocardiographic resolution of ST segment elevation, defined as a reduction of > or = 50% from the initial value; achievement of Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow; corrected TIMI frame count (cTFC); maximum serum creatine kinase (CK) level; and the type and frequency of ventricular arrhythmias.

RESULTS

The study enrolled 386 patients, 40 of whom had been receiving statin therapy before the onset of AMI. The clinical characteristics of the 2 groups were similar at baseline, with the exceptions of a significantly higher rate of hyperlipidemia in the statin group compared with the nonstatin group (P < 0.001), significantly greater chronic use of aspirin therapy (P < 0.001), and significantly greater chronic use of antihypertensive medications (beta-blockers: P = 0.004; angiotensin-converting enzyme inhibitors/angiotensin II-receptor blockers: P = 0.007; calcium channel blockers: P = 0.006). Electrocardiographic ST segment resolution after PCI was observed in 87.5% and 69.9% of the statin and nonstatin groups, respectively (hazard ratio [HR]: 3.01; 95% CI, 1.15-7.90; P = 0.025). Achievement of TIMI grade 3 flow after PCI was seen in 95.0% of the statin group and 83.5% of the nonstatin group (HR: 3.75; 95% CI, 0.88-16.0; P = NS). Patients treated with a statin had a significantly lower mean (SD) maximum CK level compared with the nonstatin group (2300 [1449] vs 3538 [3170] IU/mL, respectively; P = 0.015) and a lower cTFC after PCI (18.8 [4.0] vs 24.2 [14.2]; P = 0.017). The difference in reperfusion arrhythmias between groups was not statistically significant. After adjustment for baseline covariates, pretreatment with a statin was found to be an independent predictor of ST segment resolution after PCI (HR: 2.95; 95% CI, 1.08-8.09; P = 0.035) and prevention of impaired coronary flow (HR: 3.00; 95% CI, 1.63-5.55; P < 0.001).

CONCLUSION

In this study, receipt of chronic statin therapy before the onset of AMI was associated with improvement in epicardial perfusion and a reduction in myocardial necrosis after PCI.

Protection From Procedural Myocardial Injury by Atorvastatin Is Associated With Lower Levels of Adhesion Molecules After Percutaneous Coronary Intervention

OBJECTIVES

The goal of this work was to investigate whether protection from myocardial injury during percutaneous coronary intervention (PCI) by atorvastatin is related to reduction of endothelial inflammatory response.

BACKGROUND

In the randomized ARMYDA (Atorvastatin for Reduction of MYocardial Damage during Angioplasty) trial, 7-day pre-treatment with atorvastatin before PCI significantly reduced procedural myocardial injury; mechanisms underlying this effect are not characterized.

METHODS

In a planned subanalysis of the ARMYDA trial, a subgroup of 76 patients was blind-tested for measurement of plasma levels of vascular cell adhesion molecule-1 (VCAM-1), intercellular cell adhesion molecule-1 (ICAM-1), and E-selectin: 38 patients belonged to atorvastatin (40 mg/day) and 38 to the placebo arm. Adhesion molecules were evaluated 7 days before intervention, immediately before PCI, and after 8 and 24 h.

RESULTS

Reduction of procedural myocardial injury after statin pre-treatment was also confirmed in this subgroup. Intercellular cell adhesion molecule-1, E-selectin, and VCAM-1 levels were not different at randomization and before intervention in either arm. At 8 h, increase of ICAM-1 levels was similar in the 2 arms, whereas 24-h levels were significantly lower in the atorvastatin versus placebo group (282 +/- 56 vs. 325 +/- 70 ng/ml; p = 0.007). Attenuation of E-selectin elevation occurred at 8 h in the atorvastatin group (50 +/- 8 vs. 59 +/- 13 ng/ml; p = 0.002) and became even more significant at 24 h (57 +/- 9 vs. 73 +/- 18 ng/ml; p = 0.0008). Vascular cell adhesion molecule-1 levels were not different at any time point in the 2 arms.

CONCLUSIONS

In patients undergoing PCI, reduction of procedural myocardial injury after 7-day pre-treatment with atorvastatin is paralleled by concomitant attenuation of post-procedural increase of ICAM-1 and E-selectin levels; thus, reduction of endothelial inflammatory response may explain this protective effect of statins.

Protective role of chronic statin therapy in reducing myocardial damage during percutaneous coronary intervention

OBJECTIVE

Percutaneous coronary intervention (PCI) is frequently associated with troponin I (TnI) elevation. Experimental studies suggest that statins may reduce ischaemia-reperfusion myocardial injury. The study objective was to verify whether chronic treatment with statins might reduce the occurrence and the extent of periprocedural myocardial damage in patients undergoing PCI.

METHODS

Five hundred and fifty-two consecutive patients undergoing PCI were included: 279 were not on statins before PCI, 273 were on statins. TnI levels >or= 0.3 ng/ml were considered indicative of myocardial injury.

RESULTS

Statin-treated patients had a higher prevalence of hyperlipidaemia, previous myocardial infarction, and revascularization procedures. Coronary angiography also documented a higher prevalence of multivessel disease. No difference between the two groups was observed regarding the PCI-treated vessel, type of lesions, use of stents and of anti-IIb/IIIa inhibitors. Patients on statins showed the lowest incidence of TnI >or= 0.3 ng/ml (29 vs. 48%, P = 0.00001) and of creatine kinase-MB elevation (7 vs. 12%, P = 0.04). The mean peak TnI levels were significantly lower in patients on statins (1.07 +/- 3.8 vs. 2.73 +/- 12.3, P = 0.00006). Multivariate analysis identified preprocedural statin therapy as the only independent negative predictor of postprocedural abnormal TnI levels (odds ratio = 0.52; 95% confidence intervals 0.34-0.79; P = 0.003).

CONCLUSIONS

This study shows that chronic therapy with statins reduces the incidence of periprocedural myocardial damage after PCI. The beneficial effect of statins was independent of either the most important clinical and angiographic characteristics or the use of other cardiovascular drugs including beta-blockers. These data support the specific cardioprotective role of statins.

Reduced risks of death and CHF are associated with statin therapy administered acutely within the first 24 h of AMI

BACKGROUND

Reports have demonstrated an association between statin therapy during the first day of hospitalization for acute myocardial infarction (AMI) and reduced mortality. There are little data about whether early statin therapy reduces risk of CHF and alters timing of death.

METHODS

We identified 3226 consecutive patients with AMI from 1993 through 2000 and divided them into early statin therapy (statins were administered within the initial 24 h of hospitalization, n=220) and non-statin therapy groups (n=3006). We compared mortality risks, rates of CHF development and measures of peak CK and CK-MB values between the groups.

RESULTS

In-hospital mortality was lower in the early statin therapy group (2.7%) compared to the non-statin therapy group (9.2%), p=0.001. We observed no differences in the median time to death (statin group 132 h vs. non-statin group 72 h), p=0.3. Patients with very early statin treatment had lower peak CK (624 ng/ml) and CK-MB (46 ng/ml) values compared to non-statin patients (848 ng/ml and 84 ng/ml), p<0.01. Patients in the early statin group had lower risks of developing CHF during hospitalization (10.2 %) compared to the non-statin group (25.7%), p<0.001.

CONCLUSION

Very early administration of statin therapy during the first day of hospitalization for AMI was associated with lower in-hospital mortality, lower rates of developing CHF and reduced peak biomarker release. These data support a benefit from early statin therapy in AMI and support the need for prospective studies which test whether very early statin therapy might also reduce infarct size.

Peri-procedural myocardial injury: 2005 update

During the past three decades, percutaneous coronary intervention has become one of the cardinal treatment strategies for stenotic coronary artery disease. Technical advances, including the introduction of new devices such as stents, have expanded the interventional capabilities of balloon angioplasty. At the same time, there has been a decline in the rate of major adverse cardiac events, including Q-wave acute myocardial infarction, emergency coronary artery bypass grafting, and cardiac death. Despite these advances, the incidence of post-procedural cardiac marker elevation has not substantially decreased since the first serial assessment 20 years ago. As of now, these post-procedural cardiac marker elevations are considered to represent peri-procedural myocardial injury (PMI) with worse long-term outcome potential. Recent progress has been made for the identification of two main PMI patterns, one near the intervention site (proximal type, PMI type I) and one in the distal perfusion territory of the treated coronary artery (distal type, PMI type II) as well as for preventive strategies. Integrating these new developments into the wealth of clinical information on this topic, this review aims at giving a current perspective on the entity of PMI.

Relationship between C-Reactive Protein and the Electrocardiographic Pattern on Admission in Patients with Acute Coronary Syndrome

BACKGROUND

In patients with acute coronary syndrome (ACS), the prevalence of a primary inflammatory pathogenic component of coronary instability, as detectable by elevated C-reactive protein (CRP), varies considerably. The aim of the present study was to assess the prevalence of inflammation in patients with ACS according to the different electrocardiographic (ECG) patterns on admission.

METHODS

Hundred and thirty-six consecutive patients with the diagnosis of acute myocardial infarction were divided in three groups according to the ECG pattern on admission. Group 1 included 59 patients with ST segment elevation, group 2 included 50 patients with ST depression and/or T wave inversion and group 3 included 27 patients with no ECG changes. CRP was measured on admission in all patients. For the prevalence of inflammation analysis, we used a cutoff value of 3 mg/l.

RESULTS

CRP was above cutpoint significantly more often in patients with ST depression and/or T wave inversion (44.1% in group 1, 70% in group 2 and 40.7% in group 3; p=0.009). Patients with similar ECG pattern and CRP levels above the cutpoint presented a poorer outcome (coronary death, myocardial infarction and recurrence of instability) at one-year follow-up: 54 versus 27% for group 1, 74 versus 27% for group 2 and 45 versus 31% for group 3.

CONCLUSIONS

Patients with ST depression and/or T wave inversion on admission exhibit a higher prevalence of elevated CRP than those with ST elevation or no ECG changes, suggesting an important heterogeneity of the role of inflammatory triggers of the clinical syndromes of coronary instability.

HMG-CoA reductase inhibitors inhibit endothelial exocytosis and decrease myocardial infarct size

Three-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors protect the vasculature from inflammation and atherosclerosis by cholesterol dependent and cholesterol independent mechanisms. We hypothesized that HMG-CoA reductase inhibitors decrease exocytosis of Weibel-Palade bodies, endothelial cell granules whose contents promote thrombosis and vascular inflammation. We pretreated human aortic endothelial cells with simvastatin for 24 hours, then stimulated the cells with thrombin, and measured the amount of vWF released into the media. We then measured the effect of simvastatin on myocardial infarction in mice. Simvastatin decreased thrombin-stimulated Weibel-Palade body exocytosis by 89%. Simvastatin inhibited exocytosis in part by increasing synthesis of nitric oxide (NO), which S-nitrosylated N-ethylmaleimide sensitive factor (NSF), a critical regulator of exocytosis. Simvastatin treatment attenuated myocardial infarct size by 58% in wild-type but not eNOS knockout mice. Furthermore, simvastatin decreased endothelial exocytosis and neutrophil infiltration into ischemic-reperfused myocardium, which was mediated in part by P-selectin contained in Weibel-Palade bodies. However, simvastatin did not affect exocytosis and inflammation in myocardial infarcts of eNOS knockout mice. Inhibition of endothelial exocytosis is a novel mechanism by which HMG-CoA reductase inhibitors may reduce vascular inflammation, inhibit thrombosis, and protect the ischemic myocardium. These findings may explain part of the pleiotropic effects of statin therapy for patients with cardiovascular disease.

Oral pre-treatment with rosuvastatin protects porcine myocardium from ischaemia/reperfusion injury via a mechanism related to nitric oxide but not to serum cholesterol level

AIMS

The aim of this study was to test whether oral pre-treatment with rosuvastatin at a dosage giving clinically relevant plasma concentrations protects the myocardium against ischaemia/reperfusion injury and to investigate the involvement of nitric oxide (NO) and neutrophil infiltration.

METHODS

Pigs were given placebo (n = 7), rosuvastatin (80 mg day(-1), n =7), rosuvastatin (160 mg day(-1), n = 7) or pravastatin (160 mg day(-1), n = 7) orally for 5 days before being subjected to coronary artery ligation and reperfusion. An additional group was given rosuvastatin 160 mg day(-1) and a nitric oxide synthase (NOS) inhibitor.

RESULTS

Rosuvastatin 80 and 160 mg day(-1) resulted in plasma concentrations of 2.6 +/- 0.7 and 5.6 +/- 1.0 ng mL(-1), respectively. Serum cholesterol was not affected. Rosuvastatin 160 mg day(-1) and pravastatin limited the infarct size from 82 +/- 3% of the area at risk in the placebo group to 61 +/- 3% (P < 0.05), and to 61 +/- 2% (P < 0.05) respectively. Rosuvastatin 80 mg day(-1) limited the infarct size to 69 +/- 2%, however, this effect was not statistically significant. Rosuvastatin 160 mg day(-1) attenuated neutrophil infiltration in the ischaemic/reperfused myocardium. The protective effect of rosuvastatin 160 mg day(-1) was abolished by NOS inhibition. The expression of NOS2 and NOS3 in the myocardium did not differ between the groups.

CONCLUSIONS

Oral pre-treatment with rosuvastatin limited infarct size following ischaemia/reperfusion without affecting cholesterol levels. The cardioprotective effect is suggested to be dependent on maintained bioactivity of NO, without influencing NOS expression.

Randomized Trial of Atorvastatin for Reduction of Myocardial Damage During Coronary Intervention

Background— Small myocardial infarctions after percutaneous coronary intervention have been associated with higher risk of cardiac events during follow-up. Observational studies have suggested that statins may lower the risk of procedural myocardial injury. The aim of our study was to confirm this hypothesis in a randomized study.

Methods and Results— One hundred fifty-three patients with chronic stable angina without previous statin treatment were enrolled in the study. Patients scheduled for elective coronary intervention were randomized to atorvastatin (40 mg/d, n=76) or placebo (n=77) 7 days before the procedure. Creatine kinase-MB, troponin I, and myoglobin levels were measured at baseline and at 8 and 24 hours after the procedure. Detection of markers of myocardial injury above the upper normal limit was significantly lower in the statin group versus the placebo group: 12% versus 35% for creatine kinase-MB ( P =0.001), 20% versus 48% for troponin I ( P =0.0004), and 22% versus 51% for myoglobin ( P =0.0005). Myocardial infarction by creatine kinase-MB determination was detected after coronary intervention in 5% of patients in the statin group and in 18% of those in the placebo group ( P =0.025). Postprocedural peak levels of creatine kinase-MB (2.9±3 versus 7.5±18 ng/mL, P =0.007), troponin I (0.09±0.2 versus 0.47±1.3 ng/mL, P =0.0008), and myoglobin (58±36 versus 81±49 ng/mL, P =0.0002) were also significantly lower in the statin than in the placebo group.

Conclusions— Pretreatment with atorvastatin 40 mg/d for 7 days significantly reduces procedural myocardial injury in elective coronary intervention. These results may influence practice patterns with regard to adjuvant pharmacological therapy before percutaneous revascularization.

Squalestatin Cures Prion-infected Neurons and Protects Against Prion Neurotoxicity

A key feature of prion diseases is the conversion of the normal, cellular prion protein (PrP(C)) into beta-sheet-rich disease-related isoforms (PrP(Sc)), the deposition of which is thought to lead to neurodegeneration. In the present study, the squalene synthase inhibitor squalestatin reduced the cholesterol content of cells and prevented the accumulation of PrP(Sc) in three prion-infected cell lines (ScN2a, SMB, and ScGT1 cells). ScN2a cells treated with squalestatin were also protected against microglia-mediated killing. Treatment of neurons with squalestatin resulted in a redistribution of PrP(C) away from Triton X-100 insoluble lipid rafts. These effects of squalestatin were dose-dependent, were evident at nanomolar concentrations, and were partially reversed by cholesterol. In addition, uninfected neurons treated with squalestatin became resistant to the otherwise toxic effect of PrP peptides, a synthetic miniprion (sPrP106) or partially purified prion preparations. The protective effect of squalestatin, which was reversed by the addition of water-soluble cholesterol, correlated with a reduction in prostaglandin E(2) production that is associated with neuronal injury in prion disease. These studies indicate a pivotal role for cholesterol-sensitive processes in controlling PrP(Sc) formation, and in the activation of signaling pathways associated with PrP-induced neuronal death.

The role of statins in vascular disease

BACKGROUND

Recent publications have highlighted the benefits of statins in non-cardiac occlusive disease but also the failure of vascular surgeons to recognise and treat the risk factors for atherosclerosis, in particular hypercholesterolaemia. The aim of this review is to clarify the current experimental and clinical evidence for the use of statins in vascular disease.

METHODS

Literature compiled from an extensive search of Medline and the Cochrane database has been used for the basis of this review.

RESULTS

Experimental and clinical evidence consistently reports that statins improve endothelial dysfunction, are anti-inflammatory, anti-proliferative, anti-thrombogenic and anti-proteolytic. These effects are known to inhibit atherogenesis and improve plaque stability. Independent groups support the use of statins in the prevention of both primary and secondary cardiac events. The National Stroke association recommends their use to reduce strokes following myocardial infarction and the Heart Protection Study reports benefits in patients with non-cardiac occlusive disease.

CONCLUSIONS

There is substantial evidence advocating the use of statins in patients with clinically significant vascular disease. In the future this may evolve to include those patients at risk from neointimal hyperplasia, aneurysmal disease and ischaemia reperfusion injury.

Use of statins prior to percutaneous coronary intervention reduces myonecrosis and improves clinical outcome

Primary and secondary prevention with statins reduce major cardiac events in patients with coronary artery disease. The impact of pretreatment with statins prior to percutaneous coronary intervention (PCI) is not well established. The objective of this study was to determine if pretreatment with statins prior to PCI reduce myonecrosis and improve clinical outcome. One hundred nineteen consecutive patients with acute coronary syndrome who underwent PCI were identified. We compared the incidence of myonecrosis defined as peak elevation of CK-MB or CK three time above upper limit of normal within 24 hr and the 6-month cardiovascular event rate (death, nonfatal myocardial infarction unrelated to PCI, target vessels revascularization, and unstable angina requiring hospitalization) among patients who received statins prior to PCI (n = 63) to those who did not (n = 56). Pretreated patients were more likely to have history of myocardial infarction or revascularization (63% vs. 43%; P = 0.015), hyperlipidemia (80% vs. 48%; P = 0.001), hypertension (83% vs. 49%; P = 0.02), and use of angiotensin-converting enzyme inhibitor (62% vs. 38%; P = 0.008). The rest of baseline characteristics were similar between the two groups, including use of glycoprotein IIb/IIIa inhibitors, number of diseased vessels, and type of lesions. Patients pretreated with statins had a significantly lower incidence of myonecrosis (2% vs. 10%; P = 0.04) at 24 hr and a significantly lower clinical event (CE) rate at 6 months (17% vs. 21%; P = 0.015). Of patients not pretreated with statins, 72% were taking statins at 6 months as compared to 98% of pretreated patients. After adjusting for all baseline characteristics, use of statins prior to PCI was associated with a marked decrease in risk of all CEs (OR = 0.2; CI = 0.06-0.63; P = 0.006). Statin therapy prior to PCI may reduces peri-PCI myonecrosis and late cardiac events. These results need to be confirmed in large prospective randomized trials.

Simvastatin attenuates oxidant-induced mitochondrial dysfunction in cardiac myocytes

3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) can exert beneficial effects independently of serum cholesterol reduction by increasing the bioavailability of nitric oxide. However, it is unclear whether statins can exert such effects directly on cardiac myocytes and whether mitochondria are potential targets. Neonatal rat cardiac myocytes were cultured and subjected to oxidant stress (1 hour of 100 micromol/L H2O2). Mitochondrial membrane potential, a key determinant of cardiomyocyte viability, was assessed by flow cytometric analysis of tetramethylrhodamine ethyl ester (TMRE)-loaded cells. Hydrogen peroxide significantly reduced mitochondrial membrane potential. Incubation of the cardiac myocytes in simvastatin (> or =1 micromol/L) 1 hour before peroxide exposure significantly attenuated the loss of TMRE fluorescence. This effect was inhibited by the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) or the ATP-sensitive mitochondrial potassium channel (mitoKATP) blocker 5-hydroxydecanoate. Simvastatin attenuates mitochondrial membrane depolarization after exposure to oxidant stress. These findings provide primary evidence that myocytes can act as triggers and effectors in the cardioprotective cascade of simvastatin therapy. These results bear implications of statin therapy as a potential clinical application of pharmacological preconditioning.

Preprocedural statin medication reduces the extent of periprocedural non-Q-wave myocardial infarction

BACKGROUND

Stenting-related myocardial injury has been recognized as a frequent and prognostically important event, the extent of which depends on microcirculatory impairment in association with platelet aggregation, inflammation, and increased oxidative stress. Recent studies underscored the non-lipid-lowering effects of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) with antithrombotic, antiinflammatory, and antioxidative aspects. Thus, we tested the hypothesis that preprocedural statin therapy is associated with a reduction in the extent of stenting-related myocardial injury.

METHODS AND RESULTS

We stratified 296 consecutive patients who were undergoing stenting of a de novo stenosis according to the preprocedural status of statin therapy (229 statin-treated and 67 control patients). Incidence of periprocedural myocardial injury was assessed by analysis of creatine kinase (CK; upper limit of normal [ULN] 70 IU/L for women, 80 IU/L for men) and cardiac troponin T (cTnT; bedside test; threshold 0.1 ng/mL) before and 6, 12, and 24 hours after the intervention. Relative to control patients, the incidence of CK elevation >3x ULN was more than 90% lower in statin-treated patients (0.4% versus 6.0%, P=0.01). Statin therapy was the only factor independently associated with a lower risk of CK elevation >3x ULN (OR: 0.08, 95% CI: 0.01 to 0.75; P=0.03). The overall incidences of CK and cardiac troponin T elevation were slightly lower in statin-treated than in control patients (14.4% versus 20.9%, P=0.3, and 17.9% versus 22.4%, P=0.5, respectively).

CONCLUSIONS

Preprocedural statin therapy is associated with a reduction in the incidence of larger-sized, stenting-related myocardial infarctions. Prospective, randomized trials are warranted to further assess this cardioprotective effect of statins in coronary intervention.