The prognostic value of very low admission LDL-cholesterol levels in ST-segment elevation myocardial infarction compared in statin-pretreated and statin-naive patients undergoing primary percutaneous coronary intervention

Outcomes of Patients with Normal LDL-Cholesterol at Admission for Acute Coronary Syndromes: Lower Is Not Always Better

BACKGROUND AND AIM

There are few prospective data on the prognostic value of normal admission low-density lipoprotein cholesterol (LDL-C) in statin-naïve patients with acute coronary syndromes (ACS) who are treated with a preemptive invasive strategy. We aimed to analyze the proportion of patients with normal LDL-C at admission for ACS in our practice, and their characteristics and clinical outcomes in comparison to patients with high admission LDL-C.

PATIENTS AND METHODS

Two institutions' prospective registries of patients with confirmed ACS from Jan 2017 to Jan 2023 were used to identify 1579 statin-naïve patients with no history of prior coronary artery disease (CAD), and with available LDL-C admission results, relevant clinical and procedural data, and short- and long-term follow-up data. Normal LDL-C at admission was defined as lower than 2.6 mmol/L. All demographic, clinical, procedural, and follow-up data were compared between patients with normal LDL-C and patients with a high LDL-C level (≥2.6 mmol/L) at admission.

RESULTS

There were 242 (15%) patients with normal LDL-C at admission. In comparison to patients with high LDL-cholesterol at admission, they were significantly older (median 67 vs. 62 years) with worse renal function, had significantly more cases of diabetes mellitus (DM) (26% vs. 17%), peripheral artery disease (PAD) (14% vs. 9%), chronic obstructive pulmonary disease (COPD) (8% vs. 2%), and psychological disorders requiring medical attention (19% vs. 10%). There were no significant differences in clinical type of ACS. Complexity of CAD estimated by coronary angiography was similar between the two groups (median Syntax score 12 for both groups). There were no significant differences in rates of complete revascularization (67% vs. 72%). Patients with normal LDL-C had significantly lower left ventricular ejection fraction (LVEF) at discharge (median LVEF 52% vs. 55%). Patients with normal LDL-C at admission had both significantly higher in-hospital mortality (5% vs. 2%, RR 2.07, 95% CI 1.08-3.96) and overall mortality during a median follow-up of 43 months (27% vs. 14%, RR 1.86, 95% CI 1.45-2.37). After adjusting for age, renal function, presence of diabetes mellitus, PAD, COPD, psychological disorders, BMI, and LVEF at discharge in a multivariate Cox regression analysis, normal LDL-C at admission remained significantly and independently associated with higher long-term mortality during follow-up (RR 1.48, 95% CI 1.05-2.09).

CONCLUSIONS

A spontaneously normal LDL-C level at admission for ACS in statin-naïve patients was not rare and it was an independent risk factor for both substantially higher in-hospital mortality and mortality during long-term follow-up. Patients with normal LDL-C and otherwise high total cardiovascular risk scores should be detected early and treated with optimal medical therapy. However, additional research is needed to reveal all the missing pieces in their survival puzzle after ACS-beyond coronary anatomy, PCI optimization, numerical LDL-C levels, and statin therapy.

The prognostic importance of the Naples prognostic score for in-hospital mortality in patients with ST-segment elevation myocardial infarction

BACKGROUND

The Naples prognostic score (NPS) is an effective inflammatory and nutritional scoring system widely applied as a prognostic factor in various cancers. However, the prognostic significance of NPS is unknown in ST-segment elevation myocardial infarction (STEMI). We aimed to analyze the prognostic value of the NPS in-hospital mortality in patients with STEMI.

METHODS

The study consisted of 3828 patients diagnosed with STEMI who underwent primer percutaneous coronary intervention. As the primary outcome, in-hospital mortality was defined as all-cause deaths during hospitalization. The included patients were categorized into three groups based on NPS (group 1:NPS = 0,1,2; group 2:NPS = 3; group 3:NPS = 4).

RESULTS

Increased NPS was associated with higher in-hospital mortality rates( P  < 0.001). In the multivariable logistic regression analysis, the relationship between NPS and in-hospital mortality continued after adjustment for age, male sex, diabetes, hypertension, Killip score, SBP, heart rate, left ventricular ejection fraction, myocardial infarction type and postprocedural no-reflow. A strong positive association was found between in-hospital mortality and NPS by multivariable logistic regression analysis [NPS 0-1-2 as a reference, OR = 1.73 (95% CI, 1.04-2.90) for NPS 3, OR = 2.83 (95% CI, 1.76-4.54) for NPS 4].

CONCLUSION

The present study demonstrates that the NPS could independently predict in-hospital mortality in STEMI. Prospective studies will be necessary to confirm the performance, clinical applicability and practicality of the NPS for in-hospital mortality in STEMI.

Revisiting the lipid paradox in ST-elevation myocardial infarction in the Chinese population: findings from the CCC-ACS project

AIMS

Previous observations revealed a negative association between low-density lipoprotein cholesterol (LDL-C) and clinical outcomes following myocardial infarction, i.e., the lower level the higher mortality, which was referred to as lipid paradox. We sought to re-evaluate this association in ST-elevation myocardial infarction (STEMI) in contemporary practice.

METHODS AND RESULTS

We examined the association between admission LDL-C and in-hospital mortality among 44 563 STEMI patients enrolled from 2014 to 2019 in a nationwide registry in China. A total of 43 covariates, which were temporally classified into the following three domains were used for adjustment: (i) pre-admission characteristics; (ii) percutaneous coronary intervention (PCI)-related variables; and (iii) other in-hospital medications. In-hospital mortality was 2.01% (897/44 563). When no covariate adjustment was performed, an inversely 'J-shaped' curve was observed between admission LDL-C levels and in-hospital mortality by restricted cubic spline in logistic regression, with a threshold value of <75 mg/dL that associated with increased risk for in-hospital mortality. However, a gradual attenuation for this association was noted when step-wise adjustments were performed, with the threshold values for LDL-C decreasing from 75 mg/dL to 70 mg/dL after accounting for pre-admission characteristics, further to 65 mg/dL after accounting for PCI-related variables, and finally to no statistical association after further adjustment for other in-hospital medications.

CONCLUSIONS

In a nationwide registry in China, our findings do not support the lipid paradox in terms of in-hospital mortality in STEMI patients in contemporary practice. Previous findings in this scenario are possibly due to inadequate control for confounders.

Predictors of Microvascular Reperfusion After Myocardial Infarction

Purpose of Review

In acute ST-segment elevation myocardial infarction (STEMI), successful restoration of blood flow in the infarct-related coronary artery may not secure effective myocardial reperfusion. The mortality and morbidity associated with acute MI remain significant. Microvascular obstruction (MVO) represents failed microvascular reperfusion. MVO is under-recognized, independently associated with adverse cardiac prognosis and represents an unmet therapeutic need.

Recent Findings

Multiple factors including clinical presentation, patient characteristics, biochemical markers, and imaging parameters are associated with MVO after MI.

Summary

Impaired microvascular reperfusion is common following percutaneous coronary intervention (PCI). New knowledge about disease mechanisms underpins precision medicine with individualized risk assessment, investigation, and stratified therapy. To date, there are no evidence-based therapies to prevent or treat MVO post-MI. Identifying novel therapy for MVO is the next frontier.

Admission Low-Density Lipoprotein Cholesterol Stratified by Circulating CD14++CD16+ Monocytes and Risk for Recurrent Cardiovascular Events Following ST Elevation Myocardial Infarction: Lipid Paradox Revised

Lower level of low-density lipoprotein cholesterol (LDL-C) is paradoxically associated with increased mortality in ST elevation myocardial infarction (STEMI) patients. The underlying mechanism remains unclear. In a cohort of 220 de novo STEMI patients receiving timely primary percutaneous coronary intervention, admission LDL-C was negatively associated with circulating CD14++CD16+ monocyte counts. Moreover, admission LDL-C < 85 mg/dL was associated with increased risk for major adverse cardiovascular events (MACE) during a median follow-up of 2.7 years. After categorizing the patients according to the cutoff values of 85 mg/dL for LDL-C and the median for CD14++CD16+ monocytes, low LDL-C-associated MACE risk was only observed in those with high CD14++CD16+ monocyte counts (low LDL-C/high CD14++CD16+ monocytes vs. low LDL-C/low CD14++CD16+ monocytes: hazard ratio 5.38, 95% confidence interval 1.52 to 19.06, P = 0.009). This work provided the proof-of-principle evidence indicating a role of CD14++CD16+ monocytes in risk stratification of STEMI patients presenting with low LDL-C level. Graphical abstract.

Prediction of 1-Year Mortality from Acute Myocardial Infarction Using Machine Learning

Risk stratification at hospital discharge could be instrumental in guiding postdischarge care. In this study, the risk models for 1-year mortality using machine learning (ML) were evaluated for guiding management of acute myocardial infarction (AMI) patients. From the Korea Acute Myocardial Infarction Registry (KAMIR) dataset, 22,182 AMI patients were selected. The 1-year all-cause mortality was recorded at 12-month follow-up periods. Anomaly detection was conducted for removing outliers; principal component analysis for dimensionality reduction, recursive feature elimination algorithm for feature selection. Model selection and training were conducted with 70% of the dataset after the creation and cross-validation of hundreds of models with decision trees, ensembles, logistic regressions, and deepnets algorithms. The rest of the dataset (30%) was used for comparison between the ML and KAMIR score-based models. The mean age of the AMI patients was 64 years, 71.8% were male, and 56.7% were eventually diagnosed with ST-elevation myocardial infarction. There were 1,332 patients suffering from all-cause mortality (6%) during a median 338 days of follow-up. The ML models for 1-year mortality were well-calibrated (Hosmer-Lemeshow p >0.05) and showed good discrimination (area under the curve for test cohort: 0.918). Compared with the performance of the KAMIR score model, the ML model had a higher area under the curve, net reclassification improvement, and integrated discrimination improvement. The ML model for 1-year mortality was well-calibrated and had excellent discriminatory ability and higher performance. In a comprehensive clinical evaluation process, this model could support risk stratification and management in postdischarge AMI patients.

The Lipid Paradox is present in ST-elevation but not in non-ST-elevation myocardial infarction patients: Insights from the Singapore Myocardial Infarction Registry

Lowering low-density lipoprotein (LDL-C) and triglyceride (TG) levels form the cornerstone approach of cardiovascular risk reduction, and a higher high-density lipoprotein (HDL-C) is thought to be protective. However, in acute myocardial infarction (AMI) patients, higher admission LDL-C and TG levels have been shown to be associated with better clinical outcomes - termed the 'lipid paradox'. We studied the relationship between lipid profile obtained within 72 hours of presentation, and all-cause mortality (during hospitalization, at 30-days and 12-months), and rehospitalization for heart failure and non-fatal AMI at 12-months in ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI) patients treated by percutaneous coronary intervention (PCI). We included 11543 STEMI and 8470 NSTEMI patients who underwent PCI in the Singapore Myocardial Infarction Registry between 2008-2015. NSTEMI patients were older (60.3 years vs 57.7 years, p < 0.001) and more likely to be female (22.4% vs 15.0%, p < 0.001). In NSTEMI, a lower LDL-C was paradoxically associated with worse outcomes for death during hospitalization, within 30-days and within 12-months (all p < 0.001), but adjustment eliminated this paradox. In contrast, the paradox for LDL-C persisted for all primary outcomes after adjustment in STEMI. For NSTEMI patients, a lower HDL-C was associated with a higher risk of death during hospitalization but in STEMI patients a lower HDL-C was paradoxically associated with a lower risk of death during hospitalization. For this endpoint, the interaction term for HDL-C and type of MI was significant even after adjustment. An elevated TG level was not protective after adjustment. These observations may be due to differing characteristics and underlying pathophysiological mechanisms in NSTEMI and STEMI.

Association of hyperlipidaemia with 5-year survival after hospitalisation for acute myocardial infarction: a propensity score matched analysis

Objectives

The primary objective was to examine the association between hyperlipidaemia (HLP) and 5-year survival after incident acute myocardial infarction (AMI). The secondary objectives were to assess the effect of HLP on survival to discharge across patient subgroups, and the impact of statin prescription, intensity and long-term statin adherence on 5-year survival.

Methods

Retrospective cohort study of 7071 patients hospitalised for AMI at Mayo Clinic from 2001 through 2011. Of these, 2091 patients with HLP (age (mean±SD) 69.7±13.5) were propensity score matched to 2091 patients without HLP (age 70.6±14.2).

Results

In matched patients, HLP was associated with higher rate of survival to discharge than no HLP (95% vs 91%; log-rank <0.0001). At year 5, the adjusted HR for all-cause mortality in patients with HLP versus no HLP was 0.66 (95% CI 0.58–0.74), and patients with prescription statin versus no statin was 0.24 (95% CI 0.21 to 0.28). The mean survival was 0.35 year greater in patients with HLP than in those with no HLP (95% CI 0.25 to 0.46). Patients with HLP gained on an average 0.17 life year and those treated with statin 0.67 life year at 5 years after AMI. The benefit of concurrent HLP was consistent across study subgroups.

Conclusions

In patients with AMI, concomitant HLP was associated with increased survival and a net gain in life years, independent of survival benefit from statin therapy. The results also reaffirm the role of statin prescription, intensity and adherence in reducing the mortality after incident AMI.

Hospital Mortality in 415 798 AMI Patients: 4 Years Earlier in the Canary Islands Than in the Rest of Spain

INTRODUCTION AND OBJECTIVES

The Canary Islands has the highest mortality from diabetes in Spain. The aim of this study was to determine possible differences in mortality due to acute myocardial infarction (AMI) during hospital admission between this autonomous community and the rest of Spain, as well as the factors associated with this mortality and the population fraction attributable to diabetes.

METHODS

Cross-sectional study of hospital admissions for AMI in Spain from 2007 to 2014, registered in the Minimum Basic Data Set.

RESULTS

A total of 415 798 AMI were identified. Canary Island patients (16 317) were younger than those living in the rest of Spain (63.93 ± 13.56 vs 68.25 ± 13.94; P < .001) and death occurred 4 years earlier in the archipelago (74.03 ± 11.85 vs 78.38 ± 11.10; P < .001). This autonomous community had the highest prevalence of smoking (44% in men and 23% in women); throughout Spain, AMI occurred 13 years earlier in smokers than in nonsmokers. Patients in the Canary Islands had the highest mortality rates whether they had diabetes (8.7%) or not (7.6%), and they also showed the highest fraction of AMI mortality attributable to diabetes (9.4; 95%CI, 4.8-13.6). After adjustment for type of AMI, diabetes, dyslipidemia, hypertension, smoking, cocaine use, renal failure, sex and age, the Canary Islands showed the highest risk of mortality vs the rest of Spain (OR = 1.25; 95%CI, 1.17-1.33; P < .001) and it was one of the autonomous communities showing no significant improvement in the risk of mortality due to AMI during the study period.

CONCLUSIONS

Mortality due to AMI during hospital admission is higher in the Canary Islands than in the rest of Spain.

Machine learning for prediction of 30-day mortality after ST elevation myocardial infraction: An Acute Coronary Syndrome Israeli Survey data mining study

BACKGROUND

Risk scores for prediction of mortality 30-days following a ST-segment elevation myocardial infarction (STEMI) have been developed using a conventional statistical approach.

OBJECTIVE

To evaluate an array of machine learning (ML) algorithms for prediction of mortality at 30-days in STEMI patients and to compare these to the conventional validated risk scores.

METHODS

This was a retrospective, supervised learning, data mining study. Out of a cohort of 13,422 patients from the Acute Coronary Syndrome Israeli Survey (ACSIS) registry, 2782 patients fulfilled inclusion criteria and 54 variables were considered. Prediction models for overall mortality 30days after STEMI were developed using 6 ML algorithms. Models were compared to each other and to the Global Registry of Acute Coronary Events (GRACE) and Thrombolysis In Myocardial Infarction (TIMI) scores.

RESULTS

Depending on the algorithm, using all available variables, prediction models' performance measured in an area under the receiver operating characteristic curve (AUC) ranged from 0.64 to 0.91. The best models performed similarly to the Global Registry of Acute Coronary Events (GRACE) score (0.87 SD 0.06) and outperformed the Thrombolysis In Myocardial Infarction (TIMI) score (0.82 SD 0.06, p<0.05). Performance of most algorithms plateaued when introduced with 15 variables. Among the top predictors were creatinine, Killip class on admission, blood pressure, glucose level, and age.

CONCLUSIONS

We present a data mining approach for prediction of mortality post-ST-segment elevation myocardial infarction. The algorithms selected showed competence in prediction across an increasing number of variables. ML may be used for outcome prediction in complex cardiology settings.

Paradoxical impact of decreased low-density lipoprotein cholesterol level at baseline on the long-term prognosis in patients with acute coronary syndrome

Although statin therapy is beneficial in the setting of acute coronary syndrome (ACS), a substantial proportion of patients with ACS still do not receive the guideline-recommended lipid management in contemporary practice. We hypothesize that the low-density lipoprotein cholesterol (LDL-C) level at the time of admission might affect patient management and the subsequent outcome. Nine-hundred and forty-two consecutive patients with ACS who underwent percutaneous coronary intervention were analyzed retrospectively. The study patients were first divided into two groups based on the LDL-C level on admission: group A (n = 267), with LDL-C < 100 mg/dL; and group B (n = 675), with LDL-C ≥ 100 mg/dL. Each group was then further divided into those who were prescribed statins or not at the time of discharge from the hospital. The primary endpoint was all-cause death. In addition, we analyzed the serial changes of LDL-C within 1 year. Patients in group A were significantly older and more likely to have multiple comorbidities compared with group B. The proportion of patients who were prescribed statin at discharge was significantly smaller in group A compared with group B (57.7 vs. 77.3%, p < 0.001). During the median 4-year follow-up, there were 122 incidents of all-cause death. Multivariate Cox proportional hazard analysis revealed that LDL-C < 100 mg/dL on admission [hazard ratio (HR), 1.61; 95% confidence interval (CI), 1.09-2.39; p < 0.05] and prescription of statins at discharge (HR, 0.52; 95% CI, 0.36-0.76; p < 0.001) were associated significantly with all-cause death. Under these conditions, increasing LDL-C levels were documented during follow-up in those patients in group A when no statins were prescribed at discharge (79 ± 15-96 ± 29 mg/dL, p < 0.001), whereas these remained unchanged when statins were prescribed at discharge (79 ± 15-77 ± 22 mg/dL, p = 0.30). These results demonstrate that decreased LDL-C on admission in ACS led to less prescription for statins, which could result in increased death, probably due to underestimation of the baseline LDL-C.

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.

Effect of Metformin on Metabolites and Relation With Myocardial Infarct Size and Left Ventricular Ejection Fraction After Myocardial Infarction

Background—

Left ventricular ejection fraction (LVEF) and infarct size (ISZ) are key predictors of long-term survival after myocardial infarction (MI). However, little is known about the biochemical pathways driving LV dysfunction after MI. To identify novel biomarkers predicting post-MI LVEF and ISZ, we performed metabolic profiling in the GIPS-III randomized clinical trial (Glycometabolic Intervention as Adjunct to Primary Percutaneous Intervention in ST Elevation Myocardial Infarction). We also investigated the metabolic footprint of metformin, a drug associated with improved post-MI LV function in experimental studies.

Methods and Results—

Participants were patients with ST-segment–elevated MI who were randomly assigned to receive metformin or placebo for 4 months. Blood samples were obtained on admission, 24 hours post-MI, and 4 months post-MI. A total of 233 metabolite measures were quantified using nuclear magnetic resonance spectrometry. LVEF and ISZ were assessed 4 months post-MI. Twenty-four hours post-MI measurements of high-density lipoprotein (HDL) triglycerides (HDL-TG) predicted LVEF (β=1.90 [95% confidence interval (CI), 0.82 to 2.98]; P =6.4×10 −4 ) and ISZ (β=−0.41 [95% CI, −0.60 to −0.21]; P =3.2×10 −5 ). In addition, 24 hours post-MI measurements of medium HDL-TG (β=−0.40 [95% CI, −0.60 to −0.20]; P =6.4×2×10 −5 ), small HDL-TG (β=−0.34 [95% CI, −0.53 to −0.14]; P =7.3×10 −4 ), and the triglyceride content of very large HDL (β=−0.38 [95% CI, −0.58 to −0.18]; P =2.7×10 −4 ) were associated with ISZ. After the 4-month treatment, the phospholipid content of very large HDL was lower in metformin than in placebo-treated patients (28.89% versus 38.79%; P =7.5×10 −5 ); alanine levels were higher in the metformin group (0.46 versus 0.44 mmol/L; P =2.4×10 −4 ).

Conclusions—

HDL triglyceride concentrations predict post-MI LVEF and ISZ. Metformin increases alanine levels and reduces the phospholipid content in very large HDL particles.

Clinical Trial Registration—

URL: https://clinicaltrials.gov/ct2/show/NCT01217307 . Unique Identifier: NCT01217307.

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.