Randomized Pilot Trial on Optimal Treatment Strategy, Myocardial Changes, and Prognosis of Patients with Myocardial Infarction with Nonobstructive Coronary Arteries (MINOCA).

BACKGROUND: Myocardial infarction with nonobstructive coronary arteries (MINOCA) remains an unresolved challenge. Many different diagnostic approaches are often required to diagnose, confirm, and evaluate MINOCA. The prevalence can be as high as 13% of all acute myocardial infarction patients, indicating that this condition is not rare. At this time, there have been no completed randomized clinical trials involving MINOCA patients, and a better understanding of the mechanisms and management of these patients is important. This exploratory analysis seeks to find possible etiologic factors, the value of novel biomarkers, and the effect of different treatment strategies in patients with MINOCA. METHODS: This prospective randomized pilot trial will include 150 patients with MINOCA. A thorough clinical, laboratory, and imaging evaluation will be performed, including novel biomarkers and modern imaging techniques (heart magnetic resonance imaging and noninvasive testing). The duration of the enrollment is 18 months, and duration of the follow-up is 12 months from the enrollment of the first patient. RESULTS: The trial is registered under www.clinicaltrials.gov: NCT04538924. The study is currently recruiting participants. CONCLUSIONS: Because MINOCA is not a benign disease, the results of the current investigation could inform future diagnostic and therapeutic strategies and enhance the understanding of MINOCA patients.

Acute Myocardial Infarction with Non-Obstructive Coronary Arteries - Stratifying the Risk of a "new" Clinical Entity using an "Old" Tool

Abstract Background Some of the patients admitted for acute myocardial infarction have non-obstructive coronary artery disease (MINOCA). Their prognosis is not always benign, making it necessary the development of tools for risk stratification of these patients. Objectives To describe the characteristics of a sample of patients admitted for suspected MINOCA and to evaluate the prognostic value of GRACE score in this population. Methods This was a retrospective, observational, single-center, cohort study involving 56 consecutive patients with MINOCA. During one-year follow-up, patients were assessed for mortality and major adverse cardiovascular events (MACE) - a composite of all-cause mortality and hospitalization due to acute myocardial infarction, heart failure, ischemic stroke, and acute limb ischemia. Statistical analysis was performed using a non-parametric approach, with the Mann-Whitney U test for quantitative variables and ROC curves for assessing the discriminatory power of the Grace score in predicting cardiovascular events. The level of significance was set at 5%. Results Of the 56 MINOCA patients included in the study (median age 67 years), 55.4% were female. During the one-year follow-up, mortality rate was 5.5% and 9.1% of patients had MACE. A higher GRACE score was associated with mortality (p = 0.019; AUC 0.907; 95%CI 0.812-1.000; cut off 138) and MACE (p =0.034; AUC 0.790; 95%CI 0.632-0.948; cutoff 114). Conclusion The definition of MINOCA includes various diagnoses and prognoses, and the GRACE score is useful for risk stratification of patients with this condition.

Impact of admission hyperglycemia on short and long-term prognosis in acute myocardial infarction: MINOCA versus MIOCA.

BACKGROUND: The prognostic role of hyperglycemia in patients with myocardial infarction and obstructive coronary arteries (MIOCA) is acknowledged, while data on non-obstructive coronary arteries (MINOCA) are still lacking. Recently, we demonstrated that admission stress-hyperglycemia (aHGL) was associated with a larger infarct size and inflammatory response in MIOCA, while no differences were observed in MINOCA. We aim to investigate the impact of aHGL on short and long-term outcomes in MIOCA and MINOCA patients. METHODS: Multicenter, population-based, cohort study of the prospective registry, designed to evaluate the prognostic information of patients admitted with acute myocardial infarction to S. Orsola-Malpighi and Maggiore Hospitals of Bologna metropolitan area. Among 2704 patients enrolled from 2016 to 2020, 2431 patients were classified according to the presence of aHGL (defined as admission glucose level ≥ 140 mg/dL) and AMI phenotype (MIOCA/MINOCA): no-aHGL (n = 1321), aHGL (n = 877) in MIOCA and no-aHGL (n = 195), aHGL (n = 38) in MINOCA. Short-term outcomes included in-hospital death and arrhythmias. Long-term outcomes were all-cause and cardiovascular mortality. RESULTS: aHGL was associated with a higher in-hospital arrhythmic burden in MINOCA and MIOCA, with increased in-hospital mortality only in MIOCA. After adjusting for age, gender, hypertension, Killip class and AMI phenotypes, aHGL predicted higher in-hospital mortality in non-diabetic (HR = 4.2; 95% CI 1.9-9.5, p = 0.001) and diabetic patients (HR = 3.5, 95% CI 1.5-8.2, p = 0.003). During long-term follow-up, aHGL was associated with 2-fold increased mortality in MIOCA and a 4-fold increase in MINOCA (p = 0.032 and p = 0.016). Kaplan Meier 3-year survival of non-hyperglycemic patients was greater than in aHGL patients for both groups. No differences in survival were found between hyperglycemic MIOCA and MINOCA patients. After adjusting for age, gender, hypertension, smoking, LVEF, STEMI/NSTEMI and AMI phenotypes (MIOCA/MINOCA), aHGL predicted higher long-term mortality. CONCLUSIONS: aHGL was identified as a strong predictor of adverse short- and long-term outcomes in both MIOCA and MINOCA, regardless of diabetes. aHGL should be considered a high-risk prognostic marker in all AMI patients, independently of the underlying coronary anatomy. Trial registration data were part of the ongoing observational study AMIPE: Acute Myocardial Infarction, Prognostic and Therapeutic Evaluation. ClinicalTrials.gov Identifier: NCT03883711.

Low Free Triiodothyronine as a Predictor of Poor Prognosis in Patients With Myocardial Infarction With Non-Obstructive Coronary Arteries.

Background: Low free triiodothyronine (fT3) level is strongly associated with poor prognosis in various patient populations. However, the role of fT3 in the risk of clinical outcomes in myocardial infarction with non-obstructive coronary arteries (MINOCA) has not been studied. Our study aimed to evaluate the association between low fT3 levels and the clinical outcomes of MINOCA patients. Methods: A total of 218 MINOCA patients without a history of thyroid disease were enrolled in the study. Demographic, baseline clinical data, thyroid hormones, and other biochemical parameters were assessed in all patients. According to the fT3 levels, the present study was classified into two groups: the low fT3 group (fT3<3.5 pmol/L) and the normal fT3 group (fT3 3.5-6.5 pmol/L). The endpoint of the study was major adverse cardiac events (MACE). Results: Fifty-nine patients were in the low fT3 group and 159 patients were in the normal fT3 group. Over the two years of follow-up, 36 MACE have occurred. The occurrence of MACE was higher in the low fT3 group compared with normal fT3 group (25.4% vs 13.2%; P=0.031). Kaplan-Meier survival curves showed a significantly increased risk of MACE in patients with low fT3 (log-rank P=0.027). Multivariable logistic regression analysis stated that high fT3 was independently associated with lower risk of MACE after two years of follow up (OR, 0.623; 95% CI, 0.399- 0.972; P=0.037). Conclusion: Low fT3 levels were significantly associated with increased risk of MACE in patients with MINOCA. This finding suggests that the fT3 levels may serve as a potential biomarker in risk stratification of MINOCA patients.

The outcome of patients with myocardial infarction with non-obstructive coronary arteries (MINOCA) and impaired kidney function: a 3-year observational study.

BACKGROUND: Myocardial infarction with nonobstructive coronary arteries (MINOCA) constitutes about 10% of the cases of acute coronary syndromes (ACS). It is a working diagnosis and requires further diagnostics to determine the cause of ACS. METHODS: In this study, 178 patients were initially diagnosed with MINOCA over a period of 3 years at the Department of Invasive Cardiology of the University Clinical Hospital in Bialystok. The value of estimated glomerular filtration rate (eGFR) was calculated for all patients. The patients were divided into 2 groups depending on the value of eGFR: group 1-53 patients with impaired kidney function (eGFR < 60 mL/min/1.73 m2; 29.8%) and group 2-125 patients with normal kidney function (eGFR ≥ 60 mL/min/1.73 m2; 70.2%). RESULTS: In group 1, the mean age of patients was significantly higher than that of group 2 patients (77.40 vs 59.27; p < 0.0001). Group had more women than group 2 (73.58% vs 49.60%; p = 0.003). Group 1 patients had higher incidence rate of arterial hypertension (92.45% vs 60.80%; p < 0.0001) and diabetes (32.08% vs 9.60%; p = 0.0002) and smoked cigarettes (22.64% vs 40.80%; p = 0.020). Group 1 patients had higher incidence rate of pulmonary edema, cardiogenic shock, sudden cardiac arrest (13.21% vs 4.00%; p = 0.025), and pneumonia (22.64% vs 6.40%; p = 0.001). After the 37-month observation, the mortality rate of the patients with MINOCA was 16.85%. Among group two patients, more of them became deceased during hospitalization (7.55% vs 0.80%; p = 0.012), followed by after 1 year (26.42% vs 7.20%; p = 0.0004) and after 3 years (33.96% vs 9.6%; p < 0.0001). Multivariate analysis revealed that the factors increasing the risk of death in MINOCA are as follows: older age, low eGFR, higher creatinine concentration, low left ventricular ejection fraction, and ST elevation in ECG. CONCLUSION: Impaired kidney function is diagnosed in every third patient with MINOCA. Early and late prognosis of patents with MINOCA and renal dysfunction is poor, and their 3-year mortality is comparable to patients with myocardial infarction with significant stenosis of the coronary arteries and impaired kidney function.