Coronary Stent Thrombosis in COVID-19 Patients: A Systematic Review of Cases Reported Worldwide.

Approximately 5 million percutaneous coronary interventions are performed worldwide annually. Therefore, stent-related complications pose a serious public health concern. Stent thrombosis, although rare, is usually catastrophic, often associated with extensive myocardial infarction or death. Because little progress has been made in outcomes following stent thrombosis, ongoing research is focusing on further understanding the predictors as well as frequency and timing in various patient subgroups. Coronavirus disease-2019 (COVID-19), a viral illness caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), activates inflammatory mechanisms that potentially create a prothrombotic environment and increases the risk of local micro thromboembolism and all types of stent thrombosis. In-stent thrombosis occurrence increased during the COVID-19 pandemic, however, there is still lack of comprehensive studies describing this population. This review and worldwide analysis of coronary stent thrombosis cases related to COVID-19 summarizes all available data.

Deferred vs Immediate Stenting in Primary Percutaneous Coronary Intervention: A Collaborative Meta-analysis of Randomized Trials With Cardiac Magnetic Resonance Imaging Data.

BACKGROUND: The role of deferred vs immediate stenting during primary percutaneous coronary intervention (PCI) for patients with ST-segment elevation myocardial infarction (STEMI) remains controversial. METHODS: We undertook a collaborative meta-analysis of study-level data by searching electronic scientific databases for investigations of primary PCI patients randomized to deferred or immediate stenting and subsequent cardiac magnetic resonance imaging. Primary angiographic and imaging outcomes were slow/no-reflow and microvascular obstruction (MVO), respectively. Main secondary outcome was recurrent ischemia. RESULTS: Among 4 trials, a total of 1570 patients with STEMI were assigned to primary PCI with either deferred (n = 779) or immediate stenting (n = 791). Of these, 797 participants had analyzable cardiac magnetic resonance imaging examinations. Median clinical follow-up was 9 months. Patients treated with deferred stenting showed a lower risk of developing slow/no-reflow in the culprit vessel (risk ratio [RR], 0.54 [95% confidence interval (CI), 0.41-0.72]; P < 0.001), a similar risk for MVO (RR, 0.93 [95% CI, 0.76-1.14]; P = 0.51), and trended higher in the risk of recurrent ischemia (RR, 2.42 [95% CI, 0.88-6.63]; P = 0.09) compared with those treated with immediate stenting. The treatment effect for slow/no-reflow and MVO correlated with a thrombus score grade > 3 at the baseline angiography and with the total stent length implanted in the culprit artery. CONCLUSIONS: A strategy of deferred stenting during primary PCI improves angiographic but not imaging or clinical outcomes compared with immediate stenting. The potential lower risk for myocardial injury by deferred stenting in primary PCI patients with STEMI and high thrombus burden requires a confirmation in adequately sized randomized trials.

Acute Coronary Stent Thrombosis in Modern Era: Etiology, Treatment, and Prognosis.

Acute stent thrombosis (AST) is a rare but life-threatening complication of coronary artery stenting. AST remains a challenging task for cardiologists, despite the application of modern procedural techniques and dual-antiplatelet therapy strategies as well as improved understanding of the underlying pathophysiology. This review focuses on the prevalence, risk factors, prognosis, multiple potential underlying pathogenesis, knowledge gaps, and recommends diagnosis and individualized management strategies of AST.

Optical coherence tomography-guided primary percutaneous coronary intervention in ST-segment elevation myocardial infarction patients: a pilot study.

BACKGROUND: The objective of our study was to assess whether optical coherence tomography (OCT) guidance could guide intervention to avoid balloon angioplasty and stenting during primary percutaneous coronary intervention. METHODS: One hundred patients with ST-segment elevation myocardial infarction and thrombus-containing lesion were enrolled in this study. Thrombus aspiration was performed in all cases followed by an OCT study. After thrombectomy, no stent was implanted in residual significant stenosis (> 50%) if examination using OCT suggested that the occlusion was mostly thrombotic, provided that the patient was symptom-free and the Thrombolysis in Myocardial Infarction (TIMI) flow was ≥ 2. All patients managed only using thrombectomy underwent 1-week and 9-month angiography and OCT. Patients with significant lesion or those in whom thrombectomy failed to re-establish flow underwent standard treatment. RESULTS: Based on the OCT information, 20 patients (20%) were treated only with aspiration even in the presence of angiographically detected "high-grade stenosis." Angiogram and OCT performed at 1 week and 9 months showed a "normal vessel" without significant stenosis in all 20 cases. There were no cases of major adverse cardiovascular event (including death, myocardial infarction, and target lesion revascularization) during the in-hospital period or at the 12-month follow-up. CONCLUSIONS: The results of our pilot study suggest that ST segment elevation myocardial infarction patients with TIMI 2/3 flow in the angiogram and without significant coronary narrowing using OCT examination (even in the presence of angiographically detected "high-grade stenosis"), in whom thrombus aspiration is performed in addition to optimal medical therapy might benefit only from thrombus aspiration without plain old balloon angioplasty/stenting during primary percutaneous coronary intervention. Validation of these preliminary data in larger randomized studies is warranted.

SYNTAX score is a predictor of angiographic no-reflow in patients with ST-elevation myocardial infarction treated with a primary percutaneous coronary intervention.

OBJECTIVES: The no-reflow phenomenon has a negative prognostic value in patients with acute ST-elevation myocardial infarction (STEMI). The SYNTAX score (SS) quantifies the extent and complexity of angiographic disease and predicts long-term mortality and morbidity in STEMI. We aimed to assess the no-reflow and its possible relationships with SS and clinical characteristics in patients with STEMI treated with a primary percutaneous coronary intervention (PPCI). MATERIALS AND METHODS: In this study, 880 patients with STEMI treated with PPCI were included prospectively (646 men and 234 women, mean age 58.5±12.4 years). The SS, thrombolysis in myocardial infarction (TIMI) flow grade score, and TIMI myocardial blush grade score were determined in all patients. No-reflow was defined as TIMI grade 0, 1 and 2 flows or TIMI grade 3 with myocardial blush grade 0 and 1. The patients were divided into two groups: a normal flow group and a no-reflow group. RESULTS: No-reflow was observed in 32.8% of patients. The mean SS of the no-reflow group was higher than that of the normal flow group (19.2±6.8/12.9±6.1, P<0.001). On multivariate logistic regression analysis, SS [ß=0.872, 95% confidence interval (CI)=0.845-0.899, P<0.001], diabetes (ß=0.767, 95% CI=0.128-4.597, P=0.004), anterior myocardial infarction (ß=5.421, 95% CI=1.369-21.469, P=0.025), and thrombus grade after wiring (ß=2.537, 95% CI=1.506-4.273, P<0.001) were found to be independent predictors of no-reflow. The cutoff value of SS obtained by the receiver-operator characteristic curve analysis was 19.75 for the prediction of no-reflow (sensitivity: 70.6%, specificity: 69.4%). CONCLUSION: The SS is a predictor of no-reflow in patients with STEMI treated with PPCI.

Plaque disruption and thrombus in Ambrose's angiographic coronary lesion types.

Lesion eccentricity with irregularities on coronary angiography is associated with ruptured plaques and thrombus based on postmortem and clinical angiographic studies. However, the predictive value of such angiographic markers of plaque disruption and thrombus remains to be determined in vivo. The purpose of this study was to establish whether Ambrose's angiographic coronary lesion types and other angiographic criteria predict the presence of disrupted plaques and thrombus using intracoronary angioscopy. Angioscopy was performed before angioplasty in 60 patients with various coronary syndromes and culprit lesions that were not totally occlusive. Lesions were classified angiographically according to Ambrose's criteria as concentric, type I and II eccentric, and multiple irregularities, or as complex or noncomplex, and then compared with the corresponding angioscopic findings. Disruption and/or thrombus were seen in 17 of 19 type II eccentric lesions and 21 of 23 angiographically complex lesions and had the highest positive predictive value to detect complicated atherosclerotic plaques (type II eccentric lesions: positive predictive value 89%, 95% confidence intervals 67% to 99%; complex lesions: 91%, 95% confidence intervals 72% to 99%). We conclude that Ambrose's type II eccentric stenoses and angiographically complex lesions are strongly associated with disrupted plaques and/or thrombus as assessed by angioscopy in patients and represent unstable plaque substrates.

Influence of residual stenosis after percutaneous coronary intervention with stent implantation on development of restenosis and stent thrombosis.

The aim of this study was to assess the effects of residual stenosis after single-stent implantation on the rate of stent thrombosis, as well as restenosis within a 6-month follow-up period. Coronary angiograms of 2,157 patients with 2,523 lesions treated with a single stent were analyzed by quantitative coronary angiography before, immediately after stent implantation, and at a planned 6-month follow-up. Lesions were classified into 4 subgroups according to the degree of residual stenosis after stent implantation: group 1, gross oversizing <-15%; group 2, slight oversizing -15% to <0%; group 3, mild residual 0% to <15%; group 4, moderate residual 15% to <30%. Stent thrombosis rates were not significantly different among the 4 subgroups (group 1: 0 of 60 [0%]; group 2: 2 of 388 [0.5%]; group 3: 8 of 1,370 [0.6%]; group 4: 8 of 705 [1.1%]; p = NS for all). An adequate dosage of ticlopidine (250 mg twice daily) and aspirin (100 mg/day) led to a lower rate of stent thrombosis (6 of 2,189 cases) than inadequate dosages or missing therapy (12 of 343 cases). In 1,882 stenoses with angiographic follow-up (77.7%), gross oversizing of stents lead to a significantly higher increase of percent stenosis (p <0.001) associated with a higher restenosis rate (group 1: 34.7% vs groups 2, 3, and 4: 32.5%, 28.2%, and 29.6%, respectively). A multiple regression analysis was performed. Optimal results with regard to stent thrombosis and restenosis were achieved with mild residual stenoses between 0% and 15% after stent implantation. Oversizing of stents is no longer necessary with an adequate dosage of ticlopidine and aspirin.

The Cardiac Infarction Injury Score as a predictor for long-term mortality in survivors of a myocardial infarction.

AIMS: The Cardiac Infarction Injury Score (CIIS) is an electrocardiographic classification system that was developed as a diagnostic tool to assess the extent of cardiac injury in acute myocardial infarction. We investigated the prognostic value of the CIIS in post-myocardial infarction patients. METHODS AND RESULTS: The prognostic values of the CIIS for total and cardiac mortality was assessed in a large series (n = 3395) of patients who were enrolled in the ASPECT trial. Standard 12-lead electrocardiograms, recorded prior to hospital discharge were coded according to the CIIS and the Minnesota Code. Mean CIIS was 26 (range--8 to 59). After adjustment for other baseline characteristics, the CIIS was directly related to the risk of total mortality and cardiac mortality. At one-year follow-up the relative risks of CIIS > or = 40, CIIS 30-40 and CIIS 20-30 were significantly higher than in those with a CIIS < 20. The relative risks were, respectively, 2.3 (1.2-4.4), 2.2 (1.3-3.9) and 1.6 (0.9-2.9). At 3 year follow-up, the relative risks were, respectively, 2.1 (1.4-3.2), 1.7 (1.2-2.4) and 1.5 (1.0-2.1). The relative risks for total mortality were similar. When patients with major ECG abnormalities, as defined by the Minnesota code, were excluded, the associations were still significant in the CIIS classes 30-40 and > 40. CONCLUSION: The CIIS ECG scoring system is an important predictor for long-term cardiac mortality in post myocardial infarction patients. It can easily be automated and is efficient for classifying cardiac injury in epidemiological studies.