Absence of High Lipoprotein(a) Levels Is an Independent Predictor of Acute Myocardial Infarction without Coronary Lesions

Prognostic Implications of Coronary Artery Sclerosis in Troponin-Positive Patients with Non-Obstructive Coronary Arteries

INTRODUCTION

Coronary sclerosis is a risk factor for the progression to obstructive coronary artery disease (CAD). However, understanding its impact on the outcomes of patients with myocardial infarction and non-obstructive coronary arteries is limited. This study aimed to explore the prognostic influence of coronary sclerosis on in- and out-of-hospital events in troponin-positive patients with non-obstructive coronary arteries.

METHODS

This study was a retrospective cohort analysis based on prospectively collected data. A total of 24,775 patients who underwent coronary angiography from 2010 to 2021 in a German university hospital were screened, resulting in a final study cohort of 373 troponin-positive patients with non-obstructive coronary arteries and a follow-up period of 6.2 ± 3.1 years. Coronary sclerosis was defined as coronary plaques without angiographically detectable stenotic lesions of 50% or more in the large epicardial coronary arteries. The primary study endpoint was the occurrence of in-hospital events. Secondary endpoints included events during follow-up.

RESULTS

Patients with coronary sclerosis were significantly older (70 ± 12 vs. 58 ± 16 years, p < 0.001), had ST-segment elevation less frequently on electrocardiogram (9.4% vs. 18.7%, p = 0.013), and suffered more often from diabetes mellitus (23.3% vs. 13.1%, p = 0.009), arterial hypertension (79.6% vs. 59.8%, p < 0.001), chronic obstructive pulmonary disease (17.1% vs. 9.4%, p = 0.028), chronic kidney disease (22.2% vs. 8.4%, p < 0.001), atrial fibrillation (19.8% vs. 12.2%, p = 0.045), and valvular diseases than patients without CAD. Patients with coronary sclerosis were more likely to receive medication for primary/secondary prevention on admission and at discharge. The incidence of in- and out-of-hospital events was significantly higher in patients with coronary sclerosis (in-hospital: 42.8% vs. 29.9%, p = 0.010; out-of-hospital: 46.0% vs. 26.1%, p < 0.001). Mortality rates tended to be higher in the coronary sclerosis group (29.4% vs. 20.0%, p = 0.066).

CONCLUSION

Patients diagnosed with coronary sclerosis presented a higher incidence of comorbidities and increased medication use, and experienced higher rates of both in-hospital and out-of-hospital events, primarily due to the clustering of cardiovascular risk factors.

The correlation of atherogenic index of plasma with non-obstructive CAD and unfavorable prognosis among patients diagnosed with MINOCA

BACKGROUND

The atherogenic index of plasma (AIP) is linked to lipid metabolism and has shown considerable prognostic value in cardiovascular disorders. However, its role in myocardial infarction with non-obstructive coronary arteries (MINOCA) has not been investigated. We assessed the relationship between AIP, the severity of coronary stenosis, and prognosis in MINOCA.

METHODS

We included consecutive patients who were diagnosed with MINOCA. AIP was calculated using the base 10 logarithm of the ratio between the levels of TG and HDL-C. The patients were divided into four groups based on their AIP quartiles: Q1 (AIP<-0.145), Q2 (AIP≥-0.145and≤0.049), Q3 (AIP>0.049and≤0.253), and Q4 (AIP>0.253). All patients underwent follow-up for MACE.

RESULTS

The final analysis included 421 patients, with 188 having normal coronaries (0 stenosis) and 233 exhibiting non-obstructive coronary artery disease (CAD) (<50 % stenosis). In the multivariate logistic analysis, highest AIP (Q4) group was significantly associated with increased risk of non-obstructive CAD in MINOCA (OR,1.994;95 % CI:1.075-3.698; P = 0.029). During the follow-up period, MACE occurred in 22.8 % of MINOCA patients. Q4 group exhibited a significantly higher rate of MACE (P = 0.021). Furthermore, when both AIP and coronary stenosis status were considered, the results revealed individuals in the Q4 group with non-obstructive CAD had the highest risk of MACE (log-rank P = 0.027). The adjusted Cox analysis indicated that the Q4 group was associated with a 2.052-fold increase in the HR of MACE.

CONCLUSION

AIP exhibits a notable association with the incidence of MACE in MINOCA patients and serves as a substantial marker for non-obstructive CAD in this patient group.

Prognostic value of elevated lipoprotein (a) in patients with acute coronary syndromes: a systematic review and meta-analysis

Background

Elevated lipoprotein (a) level was recognized as an independent risk factor for significant adverse cardiovascular events in acute coronary syndrome (ACS) patients. Despite this recognition, the consensus in the literature regarding the prognostic significance of elevated lipoprotein (a) in ACS was also limited. Consequently, we conducted a thorough systematic review and meta-analysis to evaluate the prognostic relevance of elevated lipoprotein (a) level in individuals diagnosed with ACS.

Methods and results

A thorough literature review was conducted by systematically searching PubMed, Embase, and Cochrane databases until September 2023. This review specifically examined cohort studies exploring the prognostic implications of elevated lipoprotein (a) level in relation to major adverse cardiovascular events (MACE), including death, stroke, non-fatal myocardial infarction (MI), and coronary revascularization, in patients with ACS. The meta-analysis utilized aggregated multivariable hazard ratios (HR) and their respective 95% confidence intervals (CI) to evaluate prognostic implications between high and low lipoprotein (a) levels [the cut-off of high lipoprotein (a) level varies from 12.5 to 60 mg/dl]. Among 18,168 patients in the identified studies, elevated lipoprotein (a) was independently associated with increased MACE risk (HR 1.26; 95% CI: 1.17-1.35, P < 0.00001) and all-cause mortality (HR 1.36; 95% CI: 1.05-1.76, P = 0.02) in ACS patients. In summary, elevated lipoprotein (a) levels independently forecast MACE and all-cause mortality in ACS patients. Assessing lipoprotein (a) levels appears promising for risk stratification in ACS, offering valuable insights for tailoring secondary prevention strategies.

Systematic Review Registration

PROSPERO (CRD42023476543).

The impact of diabetes mellitus on the outcome of troponin-positive patients with non-obstructive coronary arteries

Background

Diabetes mellitus is a major cardiovascular risk factor for the development of coronary artery disease, but knowledge about the impact of diabetes mellitus on the outcome of patients with myocardial infarction with non-obstructive coronary arteries is limited. The aim of this study was to investigate the prognostic impact of diabetes mellitus on in- and out-of-hospital adverse events in troponin-positive patients with non-obstructive coronary arteries.

Methods and Results

A total of 373 troponin-positive patients with non-obstructive coronary arteries between 2010 and 2021 at Bergmannsheil University Hospital Bochum were enrolled, including 65 diabetics and 307 nondiabetics. The median follow-up was 6.2 years. The primary study end point was a composite of in-hospital major adverse cardiovascular events (MACE). Secondary endpoints covered MACE during follow-up.Mean age of the study cohort was 62.9 years and 49.3 % were male. Although the overall rate of in-hospital MACE was higher in diabetics (41.5 %) than in non-diabetics (33.9 %), this difference did not reach statistical significance (p = 0.240). The in-hospital mortality rate was low in both groups, 0 % of diabetes group versus 2.9 % of non-diabetic patients. During follow-up, diabetic patients had a significantly higher rate of MACE (51.9 % vs. 31.1 %, p = 0.004) and a significantly higher all-cause mortality rate than non-diabetic patients (42.3 % vs. 20.1 %, p < 0.001).

Conclusion

Our study reveals that the impact of diabetes mellitus on cardiovascular outcomes in troponin-positive patients with non-obstructive coronary arteries intensifies over the long term, leading to increased rates of both cardiovascular adverse events and overall mortality.

MINOCA biomarkers: Non-atherosclerotic aspects

Myocardial infarction in the absence of obstructive coronary artery disease (MINOCA) is an important subtype of myocardial infarction. Although comprising less than 50% stenosis in the main epicardial coronary arteries, it constitutes a severe health risk. A variety of approaches have been recommended, but definitive diagnosis remains elusive. In addition, the lack of a comprehensive understanding of underlying pathophysiology makes clinical management difficult and unpredictable. This review highlights ongoing efforts to identify relevant biomarkers in MINOCA to improve diagnosis, individualize treatment and better predict outcomes.