Heart rate variability alterations in takotsubo syndrome and related association with psychological factors: a systematic review and meta-analysis.

Psychological factors may have a precipitant role in takotsubo syndrome (TS). Aberrant Heart Rate Variability (HRV) has been reported in TS, suggesting inflexibility of the autonomous nervous system. Nevertheless, results on HRV alterations and their link with psychological factors in TS are conflicting. This work aimed to systematically explore whether TS may be associated with HRV alterations and their association with specific psychological profiles in TS patients. A literature search was conducted across databases (Pubmed, Scopus, PsycInfo, Web of Science) and empirical studies including TS patients which were evaluated in one or more HRV indices were retrieved. HRV and psychological outcomes were extracted. 10 empirical studies with 194 TS patients were included. Results showed significant alteration of HRV in TS patients, with indices compared to controls, and a progressive increase over time. Nevertheless, retrieved data presented mixed results, as also shown by a large heterogeneity in the meta-analytic findings. 2 studies found significant relationships between HRV alterations and trait-rather than state-psychological outcomes (i.e., coping strategies and emotional arousal), pointing to the need to explore the role of psychological vulnerabilities, rather than single traumatic stressors, in the association between HRV and TS.

Comprehensive echocardiographic assessment of right ventricular function, pulmonary arterial elastic properties and ventricular-vascular coupling in adult patients with repaired tetralogy of fallot: clinical significance of 3D derived indices.

We aimed to comprehensively analyze by three-dimensional speckle-tracking echocardiography (3DSTE) and Doppler echocardiography right ventricular (RV) performance, pulmonary arterial (PA) elastic properties and right ventricular-pulmonary artery coupling (RVPAC) in patients with repaired tetralogy of Fallot (rTOF) and assess the feasibility and clinical utility of related echocardiographic indices. Twenty-four adult patients with rTOF and twenty-four controls were studied. RV end-diastolic volume(3D-RVEDV), RV end-systolic volume(3D-RVESV), RV ejection fraction(3D-RVEF), RV longitudinal strain(3D-RVLS) and RV area strain(3D-RVAS) were calculated by 3DSTE. RV end-systolic area (RVESA) was obtained by planimetry. Pulmonary regurgitation (PR) was assessed as trivial/mild or significant by cardiac magnetic resonance (CMR) and color-Doppler. Pulmonary artery (PA) elastic properties were determined using two-dimensional/Doppler echocardiography. RV systolic pressure (RVSP) was measured using standard Doppler methods. RVPAC was assessed using various 3DSTE-derived parameters (3DRVAS/RVSP, 3DRVLS/RVESA, 3DRVAS/RVESV). Overall, 3DRVEF and 3DRVAS were impaired in rTOF patients compared with controls. PA pulsatility and capacitance were reduced (p = 0.003) and PA elastance was higher (p = 0.0007) compared to controls. PA elastance had a positive correlation with 3DRVEDV (r = 0.64, p = 0.002) and 3DRVAS (r = 0.51, p = 0.02). By ROC (receiver operating characteristics) analysis, 3DRVAS/RVESV, 3DRVAS/RVSP and 3DRVLS/RVESA cutoff values of 0.31%/mmHg, 0.57%/mmHg and 0.86%/mmHg, respectively, had 91%, 88% and 88% sensitivity and 81%, 81% and 79% specificity in identifying exercise capacity impairment. In rTOF patients increased 3DSTE-derived RV volumes and impaired RV ejection fraction and strain are associated with reduced PA pulsatility and capacitance and increased PA elastance. 3DSTE-derived RVPAC parameters using different afterload-markers are accurate indices of exercise capacity.

Adherence to the Mediterranean Diet in Preventing Major Cardiovascular Events in Patients with Ischemic Heart Disease: The EVA Study.

BACKGROUND: Adherence to healthy dietary patterns, such as the Mediterranean diet (Med-diet), is recommended for the maintenance of cardiovascular health. The determinants for adherence to Med-diet and its importance in secondary cardiovascular disease prevention are still unclear. The aim of the study was to evaluate the influence of sex- and psycho-socio-cultural (i.e., gender-related) factors on Med-diet adherence and its role in preventing major cardiovascular events (MACEs) in patients with ischemic heart disease (IHD). METHODS: Med-diet adherence was evaluated among 503 consecutive adults with IHD. MACEs were collected during a long-term follow-up. RESULTS: Male Bem Sex-Role Inventory score (i.e., male personality traits) and physical functional capacity were associated with higher adherence, while cohabitation with a smoker and physical inactivity with poorer adherence. During a median follow-up of 22 months, 48 participants experienced MACEs (17.5%, 8.1%, and 3.9% of patients with low, medium, and high adherence, respectively; p = 0.016). At multivariate Cox--regression analysis, a greater adherence remained inversely associated with MACEs (HR: 0.49; 95% CI: 0.29-0.82; p = 0.006) after adjusting for confounding factors. CONCLUSION: The study suggests that gender-related factors have a role in maintaining a healthy dietary pattern. Improving Med-diet adherence may lower the risk of recurring cardiovascular events.

Repeated Glutathione Sodium Salt Infusion May Counteract Contrast-Associated Acute Kidney Injury Occurrence in ST-Elevation Myocardial Infarction Patients Undergoing Primary PCI: A Randomized Subgroup Analysis of the GSH 2014 Trial.

BACKGROUND: Contrast-associated acute kidney injury (CA-AKI) is still a major concern for referring physicians, especially in the setting of ST-elevation myocardial infarction (STEMI) patients undergoing primary-PCI (pPCI). To evaluate whether glutathione sodium salt (GSS) infusion impacts favorably on CA-AKI, an unplanned exploratory data analysis of the GSH 2014 trial was performed. METHODS: One hundred patients with STEMI were assigned at random to an experimental group (No. 50) or to a placebo group (No. 50). Treatment consisted of an intravenous infusion of GSS lasting over 10 min before p-PCI. The placebo group received the same quantity of normal saline solution. After the interventions, glutathione was administered in the same doses to both groups at 24, 48 and 72 h. RESULTS: CA-AKI occurred in 5 out of 50 patients (10%) allocated to the experimental group (GSS infusion) and in 19 out of 50 patients (38%) allocated to the placebo group (p between groups < 0.001). No patients in either group required renal replacement therapy. After allowing for multiple confounders, GSS administration (OR 0.17, 95% CI 0.04-0.61) and door-to-balloon time (in hours) (OR 1.61, 95% CI 1.01-2.58) have been the only independent predictors of CA-AKI. CONCLUSIONS: the results of this sub-study, which show a significant trend towards an improved nephroprotection in the experimental group, led to the hypothesis of a possible new prophylactic approach to counteract CA-AKI using repeated GSS infusion. Subsequent studies with specific clinical outcomes would be necessary to confirm these data.

Prediction of new onset atrial fibrillation in patients with acute coronary syndrome undergoing percutaneous coronary intervention using the C2HEST and mC2HEST scores: A report from the multicenter REALE-ACS registry.

BACKGROUND: New onset atrial fibrillation (NOAF) is associated with worse clinical outcomes after acute coronary syndrome (ACS). Identification of ACS patients at risk of NOAF remains challenging. To test the value of the simple C2HEST score for predicting NOAF in patients with ACS. METHODS: We studied patients from the prospective ongoing multicenter REALE-ACS registry of patients with ACS. NOAF was the primary endpoint of the study. The C2HEST score was calculated as coronary artery disease or chronic obstructive pulmonary disease (1 point each), hypertension (1 point), elderly (age ≥ 75 years, 2 points), systolic heart failure (2 points), thyroid disease (1 point). We also tested the mC2HEST score. RESULTS: We enrolled 555 patients (mean age 65.6 ± 13.3 years; 22.9% women), of which 45 (8.1%) developed NOAF. Patients with NOAF were older (p < 0.001) and had more prevalent hypertension (p = 0.012), chronic obstructive pulmonary disease (p < 0.001) and hyperthyroidism (p = 0.018). Patients with NOAF were more frequently admitted with STEMI (p < 0.001), cardiogenic shock (p = 0.008), Killip class ≥2 (p < 0.001) and had higher mean GRACE score (p < 0.001). Patients with NOAF had a higher C2HEST score compared with those without (4.2 ± 1.7 vs 3.0 ± 1.5, p < 0.001). A C2HEST score > 3 was associated with NOAF occurrence (odds ratio 4.33, 95% confidence interval 2.19-8.59, p < 0.001). ROC curve analysis showed good accuracy of the C2HEST score (AUC 0.71, 95%CI 0.67-0.74) and mC2HEST score (AUC 0.69, 95%CI 065-0.73) in predicting NOAF. CONCLUSIONS: The simple C2HEST score may be a useful tool to identify patients at higher risk of developing NOAF after presentation with ACS.

Contrast-Induced Acute Kidney Injury and Endothelial Dysfunction: The Role of Vascular and Biochemical Parameters.

INTRODUCTION: Contrast-induced acute kidney injury (CIAKI) is one of the main causes of acute renal failure in hospitalized patients, following the administration of iodinated contrast medium used for CT scans and angiographic procedures. CIAKI determines a high cardiovascular risk and appears to be one of the most feared complications of coronary angiography, causing a notable worsening of the prognosis with high morbidity and mortality. AIM: To evaluate a possible association between the renal resistive index (RRI) and the development of CIAKI, as well as an association with the main subclinical markers of atherosclerosis and the main cardiovascular risk factors. MATERIALS AND METHODS: We enrolled 101 patients with an indication for coronary angiography. Patients underwent an assessment of renal function (serum nitrogen and basal creatinine, 48 and 72 h after administration of contrast medium), inflammation (C reactive protein (CRP), serum calcium and phosphorus, intact parathormone (iPTH), 25-hydroxyvitaminD (25-OH-VitD), serum uric acid (SUA), total cholesterol, serum triglycerides, serum glucose and insulin). All patients also carried out an evaluation of RRI, intima-media thickness (IMT), interventricular septum (IVS) and the ankle-brachial index (ABI). RESULTS: 101 patients (68 male), with a mean age of 73.0 ± 15.0 years, were enrolled for the study; 35 are affected by type 2 diabetes mellitus. A total of 19 cases of CIAKI were reported (19%), while among diabetic patients we reported an incidence of 23% (8 patients). In our study, patients with CIAKI had significantly higher RRI (p < 0.001) and IMT (p < 0.001) with respect to the patients who did not develop CIAKI. Furthermore, patients with CIAKI had significantly higher CRP (p < 0.001) and SUA (p < 0.006). CONCLUSIONS: We showed a significant difference in RRI, IMT, SUA and CRP values between the population developing CIAKI and patients without CIAKI. This data appears relevant considering that RRI and IMT are low-cost, non-invasive and easily reproducible markers of endothelial dysfunction and atherosclerosis.

A machine-learning based bio-psycho-social model for the prediction of non-obstructive and obstructive coronary artery disease.

BACKGROUND: Mechanisms of myocardial ischemia in obstructive and non-obstructive coronary artery disease (CAD), and the interplay between clinical, functional, biological and psycho-social features, are still far to be fully elucidated. OBJECTIVES: To develop a machine-learning (ML) model for the supervised prediction of obstructive versus non-obstructive CAD. METHODS: From the EVA study, we analysed adults hospitalized for IHD undergoing conventional coronary angiography (CCA). Non-obstructive CAD was defined by a stenosis < 50% in one or more vessels. Baseline clinical and psycho-socio-cultural characteristics were used for computing a Rockwood and Mitnitski frailty index, and a gender score according to GENESIS-PRAXY methodology. Serum concentration of inflammatory cytokines was measured with a multiplex flow cytometry assay. Through an XGBoost classifier combined with an explainable artificial intelligence tool (SHAP), we identified the most influential features in discriminating obstructive versus non-obstructive CAD. RESULTS: Among the overall EVA cohort (n = 509), 311 individuals (mean age 67 ± 11 years, 38% females; 67% obstructive CAD) with complete data were analysed. The ML-based model (83% accuracy and 87% precision) showed that while obstructive CAD was associated with higher frailty index, older age and a cytokine signature characterized by IL-1ß, IL-12p70 and IL-33, non-obstructive CAD was associated with a higher gender score (i.e., social characteristics traditionally ascribed to women) and with a cytokine signature characterized by IL-18, IL-8, IL-23. CONCLUSIONS: Integrating clinical, biological, and psycho-social features, we have optimized a sex- and gender-unbiased model that discriminates obstructive and non-obstructive CAD. Further mechanistic studies will shed light on the biological plausibility of these associations. CLINICAL TRIAL REGISTRATION: NCT02737982.

The Combined Treatment of Glutathione Sodium Salt and Ascorbic Acid for Preventing Contrast-Associated Acute Kidney Injury in ST-Elevation Myocardial Infarction Patients Undergoing Primary PCI: A Hypothesis to Be Validated.

The occurrence of Contrast-Associated Acute Kidney Injury (CA-AKI) in patients with ST-Elevation Myocardial Infarction (STEMI) has a negative impact on the length of hospital stay and mortality. Reactive Oxygen Species (ROS) release, along with vasoconstriction and hypoperfusion, play a key role in its development. To date, there is still no validated prophylactic therapy for this disease. The use of antioxidants, based on experimental and clinical studies, looks promising. Taking into consideration previous literature, we speculate that an early, combined and prolonged intravenous administration of both Glutathione (GSH) and ascorbic acid in STEMI patients undergoing primary Percutaneous Coronary Intervention (pPCI) may be of value in counteracting the occurrence of CA-AKI. We aimed at evaluating this hypothesis by applying a multicenter research protocol, using a double-blind randomized, placebo-controlled trial design. The primary endpoint will be to test the efficacy of this combined antioxidant therapy in reducing the occurrence of renal damage, in patients with acute myocardial infarction treated with pPCI. Furthermore, we will investigate the effect of the study compounds on changes in oxidative stress markers and platelet activation levels through bio-humoral analyses.

Relationship between non-invasively detected liver fibrosis and in-hospital outcomes in patients with acute coronary syndrome undergoing PCI.

BACKGROUND: Patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) still experience a high rate of in-hospital complications. Liver fibrosis (LF) is a risk factor for mortality in the general population. We investigated whether the presence of LF detected by the validated fibrosis 4 (FIB-4) score may indicate ACS patients at higher risk of poor outcome. METHODS: In the prospective ongoing REAl-world observationaL rEgistry of Acute Coronary Syndrome (REALE-ACS), LF was defined by a FIB-4 score > 3.25. We repeated the analysis using an APRI score > 0.7. The primary endpoint was in-hospital adverse events (AEs) including a composite of in-hospital cardiogenic shock, PEA/asystole, acute pulmonary edema and death. RESULTS: A total of 469 consecutive ACS consecutive patients were enrolled. Overall, 21.1% of patients had a FIB-4 score > 3.25. Patients with LF were older, less frequently on P2Y12 inhibitors (p = 0.021) and admitted with higher serum levels of white blood cells (p < 0.001), neutrophils to lymphocytes ratio (p < 0.001), C-reactive protein (p = 0.013), hs-TnT (p < 0.001), creatine-kinase MB (p < 0.001), D-Dimer levels (p < 0.001). STEMI presentation and higher Killip class/GRACE score were more common in the LF group (p < 0.001). 71 patients experienced 110 AEs. At the multivariate analysis including clinical and laboratory risk factors, FIB-4 > 3.25 (OR 3.1, 95%CI 1.4-6.9), admission left ventricular ejection fraction% below median (OR 9.2, 95%CI 3.9-21.7) and Killip class ≥ II (OR 6.3, 95%CI 2.2-18.4) were the strongest independent predictors of in-hospital AEs. Similar results were obtained using the APRI score. CONCLUSION: LF detected by FIB-4 score > 3.25 was associated with more severe ACS presentation and worse in-hospital AEs irrespective of clinical and laboratory variables.

Early and prolonged glutathione infusion favorably impacts length of hospital stay in ST-elevation myocardial infarction patients: a subanalysis of the GSH2014 Trial.

BACKGROUND: Developing strategies aimed to shorten the length of stay (LOS) in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) is a healthcare goal to be pursued. We carried out a subanalysis of the GSH 2014 Trial to assess the potentiality of glutathione sodium salt infusion to impact on LOS. METHODS: 100 consecutive patients with STEMI, aged more than 18 years and referred to the three enrolling centers for primary angioplasty (p-PCI), were asked to participate to the GSH 2014 Trial. Fifty patients were randomized to treatment group and fifty to placebo; treatment consisted into an intravenous infusion of glutathione sodium salt over 10 minutes before p-PCI; after interventions, glutathione was infused at the same doses at 24, 48 and 72 h elapsing time. A stepwise linear multivariate model was built in order to assess independent predictors of LOS. RESULTS: Subjects receiving infusion of glutathione sodium salt had a significantly lower LOS than subjects receiving placebo (8.6±3 vs. 10.8±4 days, P=0.006). At multivariate analysis, the randomization to GSH group was negatively associated with length of stay (ß±SEß -1.64±0.74, cumulative R2 0.43, P=0.03) independently from age, sex, cardiovascular risk factors, number of treated vessels, infarct-related coronary artery (left anterior descending artery as reference) and enrolment hospital. CONCLUSIONS: Results from this subanalysis support the hypothesis that an early and prolonged glutathione sodium salt administration, as antioxidant therapy to patients with STEMI, may favorably impact on LOS. Further studies with larger sample size are necessary to confirm these data.

Protective Biomolecular Mechanisms of Glutathione Sodium Salt in Ischemia-Reperfusion Injury in Patients with Acute Coronary Syndrome-ST-Elevation Myocardial Infarction.

Ischemia-Reperfusion Injury (IRI) is responsible for adverse outcomes in patients with ST-Elevation Myocardial Infarction (STEMI). Oxidative stress, resulting from the production of Reactive Oxygen Species (ROS) and low availability of Glutathione (GSH), are the two main mediators of IRI. The effectiveness of exogenous antioxidant therapy in this scenario is still debated, since the encouraging results obtained in animal models have not been fully reproduced in clinical studies. In this review we focus on the role of GSH, specifically on the biomolecular mechanisms that preserve myocardial cells from damage due to reperfusion. In this regard, we provide an extensive discussion about GSH intrinsic antioxidant properties, its current applications in clinical practice, and the future perspectives.

Unraveling Pathophysiology of Takotsubo Syndrome: The Emerging Role of the Oxidative Stress's Systemic Status.

Takotsubo Syndrome (TTS) is usually triggered by emotional or physical stressors, thus suggesting that an increased sympathetic activity, leading to myocardial perfusion abnormalities and ventricular dysfunction, plays a major pathogenetic role. However, it remains to be elucidated why severe emotional and physical stress might trigger TTS in certain individuals but not others. Clinical research has been focused mainly on mechanisms underlying the activation of the sympathetic nervous system and the occurrence of myocardial ischemia in TTS. However, scientific evidence shows that additional factors might play a pathophysiologic role in the condition's occurrence. In this regard, a significant contribution arrived from metabolomics studies that followed the systemic response to TTS. Specifically, preliminary data clearly show that there is an interplay between inflammation, genetics, and oxidative status which might explain susceptibility to the condition. This review aims to sum up the established pathogenetic factors underlying TTS and to appraise emerging mechanisms, with particular emphasis on oxidative status, which might better explain susceptibility to the condition.

Endothelial Progenitor Cells in Coronary Artery Disease: From Bench to Bedside.

Endothelial progenitor cells (EPCs) are a heterogeneous group of cells present in peripheral blood at various stages of endothelial differentiation. EPCs have been extensively investigated in patients with coronary artery disease (CAD), with controversial findings both on their role in atherosclerosis progression and in the process of neointimal growth after a percutaneous coronary intervention (PCI). Despite nearly 2 decades of experimental and clinical investigations, however, the significance of EPCs in clinical practice remains unclear and poorly understood. This review provides an update on the role of EPCs in the most common clinical scenarios that are experienced by cardiologists managing patients with CAD. We here summarize the main findings on the association of EPCs with cardiovascular risk factors, coronary atherosclerosis, and myocardial ischemia. We then discuss the potential effects of EPCs in post-PCI in-stent restenosis, as well as most recent findings with EPC-coated stents. Based on the mounting evidence of the relationship between levels of EPCs and several different adverse cardiovascular events, EPCs are emerging as novel predictive biomarkers of long-term outcomes in patients with CAD.

Reduction in emergency access for acute myocardial infarction during the COVID-19 pandemic: a survey from the greater area of Rome.

BACKGROUND: On March 9, 2020, the Italian government imposed a national lockdown to tackle the COronaVIrus Disease 19 (COVID-19) pandemic, including stay at home recommendations. The precise impact of COVID-19 scare and lockdown on emergency access for acute myocardial infarction (MI) is still subject to debate. METHODS: Data on all patients undergoing invasive coronary angiography at 9 hospitals in the greater area of Rome, Italy, between February 19, 2020 and March 29, 2020 were retrospectively collected. Incidence of ST-elevation MI (STEMI), and non-ST-elevation MI (NSTEMI), as well as corresponding percutaneous coronary intervention (PCI), was compared distinguishing two different 20-day time periods (before vs. on or after March 10, 2020). RESULTS: During the study period, 1068 patients underwent coronary angiography, 142 (13%) with STEMI and 169 (16%) with NSTEMI. The average daily number of STEMI decreased from 4.3 before the lockdown to 2.9 after the lockdown (P=0.021). Similarly, the average daily number of NSTEMI changed from 5.0 to 3.5 (P=0.028). The average daily number of primary PCI changed from 4.2 to 2.9 (P=0.030), while the average daily number of PCI for NSTEMI changed from 3.5 to 2.5 (P=0.087). For STEMI patients, the time from symptom onset to hospital arrival (onset-to-door time less than three hours) showed a significant increase after the lockdown (P=0.018), whereas door-to-balloon time did not change significantly from before to after the lockdown (P=0.609). CONCLUSIONS: The present study, originally reporting on the trends in STEMI and NSTEMI in the Rome area, highlights that significant decreases in the incidence of both acute coronary syndromes occurred between February 19, 2020 and March 29, 2020, together with increases in time from symptom onset to hospital arrival, luckily without changes in door-to-balloon time.

A Pilot Study on the 1H-NMR Serum Metabolic Profile of Takotsubo Patients Reveals Systemic Response to Oxidative Stress.

Takotsubo syndrome (TTS) presents as an acute coronary syndrome characterized by severe left ventricular (LV) dysfunction and non-obstructive coronary artery disease that typically shows spontaneous recovery within days or weeks. The mechanisms behind TTS are mainly related to beta-adrenergic overstimulation and acute endogenous catecholamine surge, both of which could increase oxidative status that may induce further deterioration of cardiac function. Although several studies reported evidence of inflammation and oxidative stress overload in myocardial tissue of TTS models, systemic biochemical evidence of augmented oxidant activity in patients with TTS is lacking. In this study, serum samples of ten TTS patients and ten controls have been analyzed using 1H-NMR spectroscopy. The results of this pilot study show a marked alteration in the systemic metabolic profile of TTS patients, mainly characterized by significant elevation of ketone bodies, 2-hydroxybutyrate, acetyl-L-carnitine, and glutamate levels, in contrast with a decrease of several amino acid levels. The overall metabolic fingerprint reflects a systemic response to oxidative stress caused by the stressor that triggered the syndrome's onset.

D-dimer for risk stratification and antithrombotic treatment management in acute coronary syndrome patients: asystematic review and metanalysis.

BACKGROUND: Data on the prognostic role of D-dimer in patients with acute coronary syndrome (ACS) are controversial. Our aim was to summarize current evidence on the association between D-dimer levels and short/long-term poor prognosis of ACS patients. We also investigated the association between D-dimer and no-reflow phenomenon. METHODS: Systematic review and metanalysis of observational studies including ACS patients and reporting data on D-dimer levels. PubMed and SCOPUS databases were searched. Data were combined with hazard ratio (HR) and metanalysed. The principal endpoint was a composite of cardiovascular events (CVEs) including myocardial infarction, all-cause and cardiovascular mortality. RESULTS: Overall, 32 studies included in the systematic review with 28,869 patients. Of them, 6 studies investigated in-hospital and 26 studies long-term outcomes. Overall, 23 studies showed positive association of high D-dimer levels with CVEs. D-dimer levels predicted poor prognosis in all studies reporting in-hospital outcomes. Five studies satisfied inclusion criteria and were included in the metanalysis, with a total of 8616 patients. Median follow-up was 13.2 months with 626 CVEs. The pooled HR for D-dimer levels and CVEs was 1.264 (95% CI 1.134-1.409). Five out of 7 studies (4195 STEMI patients) investigating the association between D-dimer levels and no-reflow showed a positive correlation of D-dimer levels with no-reflow. CONCLUSIONS: In patients with ACS, D-dimer was associated with higher in-hospital and short/long-term complications. D-dimer was also higher in patients with no-reflow phenomenon. The use of D-dimer may help to identify patients with residual thrombotic risk after ACS. TRIAL REGISTRATION: The review protocol was registered in PROSPERO International Prospective Register of Systematic Reviews: CRD42021267233 .