Impact of long-term statin pretreatment on myocardial damage in ST elevation myocardial infarction (from the AIDA STEMI CMR Substudy)

Meta-Analysis on the Efficacy of High-Dose Statin Loading Before Percutaneous Coronary Intervention in Reducing No-Reflow Phenomenon in Acute Coronary Syndrome

Currently, guidelines recommend the uptake of high-dose statins before and after percutaneous coronary intervention (PCI) in patients with acute coronary syndrome. However, the association of high-dose statins with the incidence of the no-reflow phenomenon remains unclear. This study aimed to review the evidence of preprocedural high-dose statin therapy to reduce no-reflow incidence after PCI. PubMed, Embase, and Google Scholar were searched from inception until May 2022 for studies comparing high-dose statins with low-dose or no statin therapy before PCI. Studies reporting the no-reflow phenomenon were shortlisted. The National Institutes of Health tool for randomized and cohort studies was used to assess the quality of included studies. A random-effects model was used to derive odds ratios (ORs) and their corresponding 95% confidence intervals (CIs). A total of 11 studies were included, with a population of 4,294 patients. The use of high-dose statins before PCI significantly reduced postprocedural no-reflow (OR 0.51, 95% CI 0.35 to 0.74, p = 0.0005, I² = 32%). A total of 7 studies included patients who underwent PCI without previous use of statins. A significant decrease in overall no-reflow events was observed with high-intensity statin treatment versus low-intensity statin/placebo (OR 0.55, 95% CI 0.34 to 0.88, p = 0.01, I² = 25%) among patients who were statin naive. Acute high-dose statin therapy before PCI significantly reduces the hazard of post-PCI no-reflow events in patients with acute coronary syndrome. Our results encourage the routine use of statins before PCI.

Impact of Prior Statin Therapy on In-Hospital Outcome of STEMI Patients Treated with Primary Percutaneous Coronary Intervention

Background: Prior statin therapy has a cardioprotective effect in patients undergoing elective or urgent percutaneous coronary intervention (PCI). However, data on patients with ST-elevation myocardial infarction (STEMI) undergoing primary PCI are still controversial. We retrospectively evaluated the effect of prior statin therapy on in-hospital clinical outcomes in consecutive STEMI patients undergoing primary PCI. Methods: A total of 1790 patients (mean age 67 ± 11 years, 1354 men) were included. At admission, all patients were interrogated about prior (>6 months) statin therapy. The primary endpoint of the study was the composite of in-hospital mortality, acute pulmonary edema, and cardiogenic shock in patients with or without prior statin therapy. Results: A total of 427 patients (24%) were on prior statin therapy. The incidence of the primary endpoint was similar in patients with or without prior statin therapy (15% vs. 16%; p = 0.38). However, at multivariate analysis, prior statin therapy was associated with a lower risk of the primary endpoint, after adjustment for major prognostic predictors (odds ratio 0.61 [95% CI 0.39−0.96]; p = 0.03). Conclusions: This study demonstrated that prior statin therapy is associated with a better in-hospital clinical outcome in patients with STEMI undergoing primary PCI compared to those without prior statin therapy.

Do We Really Need Aspirin Loading for STEMI?

Aspirin loading (chewable or intravenous) as soon as possible after presentation is a class I recommendation by current ST elevation myocardial infarction (STEMI) guidelines. Earlier achievement of therapeutic antiplatelet effects by aspirin loading has long been considered the standard of care. However, the effects of the loading dose of aspirin (alone or in addition to a chronic maintenance oral dose) have not been studied. A large proportion of myocardial cell death occurs upon and after reperfusion (reperfusion injury). Numerous agents and interventions have been shown to limit infarct size in animal models when administered before or immediately after reperfusion. However, these interventions have predominantly failed to show significant protection in clinical studies. In the current review, we raise the hypothesis that aspirin loading may be the culprit. Data obtained from animal models consistently show that statins, ticagrelor, opiates, and ischemic postconditioning limit myocardial infarct size. In most of these studies, aspirin was not administered. However, when aspirin was administered before reperfusion (as is the case in the majority of studies enrolling STEMI patients), the protective effects of statin, ticagrelor, morphine, and ischemic postconditioning were attenuated, which can be plausibly attributable to aspirin loading. We therefore suggest studying the effects of aspirin loading before reperfusion on the infarct size limiting effects of statins, ticagrelor, morphine, and/ or postconditioning in large animal models using long reperfusion periods (at least 24 h). If indeed aspirin attenuates the protective effects, clinical trials should be conducted comparing aspirin loading to alternative antiplatelet regimens without aspirin loading in patients with STEMI undergoing primary percutaneous coronary intervention.

Effect of High-Dose Statin Pretreatment for Myocardial Perfusion in Patients Receiving Percutaneous Coronary Intervention (PCI): A Meta-Analysis of 15 Randomized Studies

Background

For coronary artery disease, percutaneous coronary intervention (PCI) is the preferred treatment. Reperfusion injury is a common and serious complication of PCI. Studies showed that early statin therapy has a favorable prognostic impact for patients undergoing PCI. However, the effects of statins on improving post-PCI myocardial perfusion are still unclear. In this study we evaluated the potential effect of high-dose statin pretreatment on postprocedure myocardial perfusion and MACE rate in patients receiving PCI.

Material/Methods

We searched randomized controlled trials that evaluated the effect of high-dose statin pretreatment on post-PCI TIMI flow grade and MACE in patients undergoing PCI from the databases of PubMed, Embase, and Cochrane Library. All data were pooled for analysis and were stratified by type of statin, clinical presentation, and current statin therapy status in subgroup.

Results

Fifteen RCTs with 4240 individuals were selected. The pooled analysis showed that high-dose statin pretreatment before PCI significantly improved the final TIMI flow grade compared with the control group (OR=0.61, 95% CI: 0.46 to 0.80, p=0.0005), and showed reduced incidence of MACE (OR=0.53, 95%CI: 0.39 to 0.71, p<0.0001). In subgroup analysis, the beneficial effect of high-dose statin was significant in statin-naive treatment patients, ACS patients, and patients on atorvastatin therapy, but no difference occurred in rosuvastatin, previous statin therapy, and stable angina patients.

Conclusions

High-dose statin pretreatment has an important effect on postprocedure myocardial perfusion by improving the TIMI flow in patients undergoing PCI, and high-dose statin preloading also reduces the incidence of MACE.

Relation of Low-Density Lipoprotein Cholesterol With Microvascular Injury and Clinical Outcome in Revascularized ST-Elevation Myocardial Infarction

BACKGROUND

Microvascular injury (MVI) after primary percutaneous coronary intervention for ST-elevation myocardial infarction (STEMI) is a major determinant of adverse clinical outcome. Experimental data indicate an impact of hypercholesterolemia on MVI; however, there is a lack of clinical studies confirming this relation. We aimed to investigate the association of cholesterol concentrations on admission with MVI visualized by cardiac magnetic resonance imaging and clinical outcome in STEMI patients treated by primary percutaneous coronary intervention.

METHODS AND RESULTS

In this prospective, observational study, we included 235 consecutive revascularized STEMI patients. Cholesterol (total cholesterol, low-density lipoprotein [LDL], and high-density lipoprotein cholesterol) and triglyceride concentrations were determined at presentation. Cardiac magnetic resonance scans were performed 2 (2-4) days after infarction to assess infarct characteristics, including MVI. Clinical end point was the occurrence of major adverse cardiac events (MACE) comprising all-cause mortality, nonfatal reinfarction, and new congestive heart failure. Patients with MVI (n=129; 55%) showed higher levels of total cholesterol (204 [172-226] versus 185 [168-212] mg/dL; P=0.01) and LDL cholesterol (142 [113-166] versus 118 [103-149] mg/dL; P=0.001), whereas high-density lipoprotein cholesterol and triglycerides did not differ significantly. In multivariable analysis, including all significant clinical and cardiac magnetic resonance determinants of MVI, LDL concentration emerged as an independent predictor of MVI (odds ratio, 1.02 [95% confidence interval, 1.01-1.02]; P=0.002). Furthermore, increased LDL cholesterol (>150 mg/dL) significantly predicted the occurrence of major adverse cardiac events (hazard ratio, 3.09 [95% confidence interval, 1.22-7.87]; P=0.01).

CONCLUSIONS

In STEMI patients undergoing primary percutaneous coronary intervention, baseline LDL cholesterol concentrations were independently associated with MVI, revealing a clinically relevant link between LDL metabolism and MVI in acute STEMI.

Statin-Induced Cardioprotection Against Ischemia-Reperfusion Injury: Potential Drug-Drug Interactions. Lesson to be Learnt by Translating Results from Animal Models to the Clinical Settings

Numerous interventions have been shown to limit myocardial infarct size in animal models; however, most of these interventions have failed to have a significant effect in clinical trials. One potential explanation for the lack of efficacy in the clinical setting is that in bench models, a single intervention is studied without the background of other interventions or modalities. This is in contrast to the clinical setting in which new medications are added to the "standard of care" treatment that by now includes a growing number of medications. Drug-drug interaction may lead to alteration, dampening, augmenting or masking the effects of the intended intervention. We use the well described model of statin-induced myocardial protection to demonstrate potential interactions with agents which are commonly concomitantly used in patients with stable coronary artery disease and/or acute coronary syndromes. These interactions could potentially explain the reduced efficacy of statins in the clinical trials compared to the animal models. In particular, caffeine and aspirin could attenuate the infarct size limiting effects of statins; morphine could delay the onset of protection or mask the protective effect in patients with ST elevation myocardial infarction, whereas other anti-platelet agents (dipyridamole, cilostazol and ticagrelor) may augment (or mask) the effect due to their favorable effects on adenosine cell reuptake and intracellular cAMP levels. We recommend that after characterizing the effects of new modalities in single intervention bench research, studies should be repeated in the background of standard-of-care medications to assure that the magnitude of the effect is not altered before proceeding with clinical trials.

Statin use associated with a reduced risk of pneumonia requiring hospitalization in patients with myocardial infarction: a nested case-control study

BACKGROUND

Statins have been reported to prevent adverse cardiovascular events in patients with myocardial infarction (MI). However, the association of statin use and the risk of pneumonia requiring hospitalization in MI patients remains unclear.

METHODS

A nested case-control study was conducted by using data from the National Health Insurance Research Database of Taiwan. Among 24,975 patients with MI, 2686 case patients with pneumonia requiring hospitalization were age- and sex-matched with 10,726 control patients using the incidence density sampling approach. Duration and dosage of statin use were obtained from pharmaceutical claims. Conditional logistic regression analyses were used to estimate the risk of hospitalization for pneumonia associated with statin use adjusted for patient's demographics, medical conditions and prescribed medications.

RESULTS

Statin use was associated with a 15% reduced risk of pneumonia requiring hospitalization among MI patients (adjusted odds ratio [aOR] = 0.85, 95% confidence interval [CI] = 0.77-0.95, P = 0.004). The association was more significant for MI patients unexposed to statin pretreatment (aOR = 0.76, 95% CI = 0.64-0.90, P = 0.001). Statins also exhibited favorable benefits in a time- and dose-dependent manner. The results were consistent in various subgroup analysis of the patients who were female, age ≥ 65 years, a low CHADS2 (i.e. congestive heart failure, hypertension, diabetes mellitus, previous stroke and age > 75 years old) score, and fewer comorbidities. Atorvastatin, fluvastatin and simvastatin were the most common prescribed statins and had similar effects.

CONCLUSIONS

Statins might be considered as an adjunctive therapy to reduce the risk of hospitalization for pneumonia for MI patients under thorough evaluation of individual comorbidities, previous statin use and optimal dosage.

Statins and myocardial infarction: Type, dose, and administration time: Does it matter?

Patients with ST-elevation myocardial infarction (STEMI) constitute a vulnerable group that demands the careful assessment and application of all the up-to-date clinical and experimental knowledge, with final aim, the improvement of their prognosis. Statins are an indispensable part of the primary and secondary prevention of coronary artery disease (CAD), not only due to their strong hypolipidemic effect, but also due to their numerous pleiotropic properties that play an important role in the treatment of CAD, especially when the more vulnerable group of STEMI patients is addressed. Nevertheless, there are still issues that require further discussion and clarification, such as the type of statin, the dose of the regimen, the administration time, and the treatment duration.

Myocardial Infarct Size in Patients on Long-Term Statin Therapy Undergoing Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction

Statin pretreatment has been reported to have a cardioprotective effect in patients undergoing elective or urgent percutaneous coronary intervention (PCI). However, data on patients with ST-elevation myocardial infarction (STEMI) undergoing primary PCI are still controversial. We prospectively evaluated the effect of long-term statin therapy on infarct size (IS), myocardial salvage index (MSI), and microvascular obstruction (MVO) in consecutive patients with STEMI who underwent primary PCI. Two-hundred thirty patients with STEMI (mean age 61 ± 11 years, 183 men) who underwent primary PCI were evaluated with cardiac magnetic resonance (CMR) imaging during hospitalization (median 4 days after primary PCI). In all patients, we measured peak troponin I level, whereas IS, MSI, and MVO were determined by CMR. Fifty patients (22%) were on long-term statin therapy and showed a significantly lower troponin I peak value compared to patients without previous statins (54 ± 47 vs 88 ± 106 ng/ml; p = 0.02). At CMR evaluation, IS related to the index event was significantly smaller (12.5 ± 11.5 vs 18.5 ± 18.5 g, p = 0.05), and MSI was higher (0.68 ± 0.25 vs 0.52 ± 0.30; p <0.01) in patients with previous statin therapy. MVO was also less frequent (10% vs 20%; p = 0.14) in this group. At multivariate analysis, previous statin therapy remained significantly associated with IS and MSI (p = 0.05 and 0.02, respectively). In conclusion, this study suggests that long-term statin therapy before primary PCI in patients with STEMI is associated with smaller IS and higher MSI. Future studies are warranted to confirm these findings and to investigate potential clinical implications.