Incidence, Predictors and Clinical Outcomes of Stent Thrombosis Following Percutaneous Coronary Intervention in Contemporary Practice

Prevalence and clinical outcomes of acute myocardial infarction in patients presenting with major trauma

BACKGROUND

The occurrence and sequelae of acute myocardial infarction (AMI) in major trauma patients is underexplored across both trauma and cardiology specialties. Coronary reperfusion greatly reduces the risk of significant morbidity and mortality in AMI. However, in patients presenting with significant injuries, concurrent AMI presents a competing management priority given the increase in risk of bleeding with standard anticoagulation and antiplatelet therapy, which may be contraindicated. This study aimed to evaluate the epidemiology and clinical outcomes associated with AMI in a contemporary major trauma cohort.

METHODS

This study used data from the Victorian State Trauma Registry (VSTR). All adult patients with major trauma from 1 January 2013 to 31 December 2022 were included. Patients that died prior to hospital arrival were excluded. AMI was identified by ICD-10-AM diagnosis codes recorded against the first hospital admission. Clinical outcomes included in-hospital mortality, length of stay, and discharge destination.

RESULTS

28,928 patients were identified over the 10-year study period. AMI occurred in 401 patients (1.4 %). AMI patients were older, had more comorbidities and were more frequently on anticoagulation or antiplatelet therapy. Low impact fall was the most common trauma mechanism in AMI patients. Patients with AMI experienced longer hospital stays (12 [7-20] versus 7 [4-12] days, p < 0.001) and higher rates of in-hospital mortality (adjusted RR 1.45, 95 % CI 1.25-1.65).

CONCLUSION

AMI in the setting of major trauma occurs in an older, more comorbid, and vulnerable group of patients. AMI is associated with an increased risk of in-hospital mortality and prolonged hospital stay in the setting of major trauma, underscoring the importance of identifying and treating major trauma associated AMI in a timely and effective manner.

Ten-year clinical outcomes after drug-eluting stents implantation according to clinical presentation-Insights from the DECADE cooperation

BACKGROUND

Investigations of very long-term outcomes after percutaneous coronary intervention (PCI) with drug-eluting stents (DES) according to clinical presentation are scarce. Here, we investigated the 10-year clinical outcomes of patients undergoing DES-PCI according to clinical presentation.

METHODS

Patient-level data from five randomized trials with 10-year follow-up after DES-PCI were pooled. Patients were dichotomized into acute coronary syndrome (ACS) or chronic coronary syndrome (CCS) groups as per clinical presentation. The primary outcome was all-cause death. Secondary outcomes were cardiovascular death, myocardial infarction (MI), definite stent thrombosis (ST) and repeat revascularization involving the target lesion (TLR), target vessel (TVR) or non-target vessel (nTVR).

RESULTS

Of the 9700 patients included in this analysis, 4557 presented with ACS and 5143 with CCS. Compared with CCS patients, ACS patients had a higher risk of all-cause death and nTVR in the first year, but comparable risk thereafter. In addition, ACS patients had a higher risk of MI [adjusted hazard ratio 1.21, 95% confidence interval (1.04-1.41)] and definite ST [adjusted hazard ratio 1.48, 95% confidence interval (1.14-1.92)], while the risk of TLR and TVR was not significantly different up to 10-year follow-up.

CONCLUSIONS

Compared to CCS patients, ACS patients treated with PCI and DES implantation have an increased risk of all-cause death and repeat revascularization of remote vessels up to 1 year, with no significant differences thereafter and up to 10-year follow-up. ACS patients have a consistently higher risk of MI and definite ST. Whether these differences persist with current antithrombotic and secondary prevention therapies requires further investigation.

High platelet reactivity strongly predicts early stent thrombosis in patients with drug-eluting stent implantation

Stent thrombosis (ST) is a fatal complication after percutaneous coronary intervention (PCI). The association between P2Y12 reaction unit (PRU) level and stent thrombosis occurrence remains unclear. Based on the multicenter, observational PTRG-DES (Platelet function and genoType-Related long-term proGnosis in DES-treated patients) registry of patients with drug-eluting stents (DES) implantation, a total of 11,714 patients with PRU values were analyzed. We sought to identify the predictors of early stent thrombosis (EST) and compared the primary outcome, a composite of cardiac death, myocardial infarction, and revascularization, between EST and non-EST groups. EST, defined as definite ST within 1 month after index PCI, occurred in 51 patients. PRU values were significantly higher in the EST group (263.5 ± 70.8 vs. 217.5 ± 78.7, p < 0.001). In multivariable analysis, PRU ≥ 252 (OR, 5.10; 95% CI 1.58-16.46; p = 0.006) and aspirin reaction unit ≥ 414 (OR 4.85; 95% CI 1.07-21.97; p = 0.040) were independent predictors of EST. The cumulative incidence of primary composite outcome at one year was significantly higher in the EST group (38.2% vs. 3.9%, Log-rank p < 0.001). In patients treated with clopidogrel after successful DES implantation, EST was associated with higher platelet reactivities, and a greater risk of cardiovascular events.Trial Registration: clinicaltrials.gov Identifier: NCT04734028.

Enhanced Stent Imaging System Guided Percutaneous Coronary Intervention Is Linked to Optimize Stent Placement

Stent under-expansion is a predictor of restenosis and stent thrombosis. It remains uncertain whether enhanced stent imaging (ESI) (CLEARstent) guidance can improve stent under-expansion. Our aim was to assess the effect of using ESI on stent under-expansion, after percutaneous coronary intervention (PCI) in a single center, cross-sectional observational study. Participants attending our cardiology clinic with stable angina or acute coronary syndrome, from March to September 2020 were recruited. A total of 164 patients who underwent post-PCI ESI (CLEARstent) were compared with 77 age- and sex-matched control patients. Post-procedural minimal lumen diameter (MLD) was calculated. The patients in the ESI-guided PCI group, had a median age of 61 (54-69 IQR 25-75) years and 76.8% (n = 126) were males. The patients in ESI-guided PCI group had a greater minimal lumen diameter compared with the X-ray guided PCI group (βeta coefficient:2.88 (95% CI:2.58-2.99) vs βeta coefficient 2.55 (95% CI 2.34-2.63), P < .001). Our finding supports the use of the ESI system to optimize stent placement as expressed by the MLD.

A nightmare of clopidogrel resistance in a resource-limited setting: case report of subacute stent thrombosis

BACKGROUND

Stent thrombosis, a life-threatening complication of percutaneous coronary intervention (PCI) continues to occur despite effective antiplatelet regimens and improved stenting methods. Noncompliance with dual antiplatelet therapy is the most common etiology; however, in spite of timely and their optimum administration the rates of recurrent myocardial infarction (MI) and stent thrombosis remain high. Clopidogrel resistance is increasingly evoked with elevated risk of anterothrombotic events particularly in the setting of stent implantation. In this case report, we present a case of subacute stent thrombosis associated with clopidogrel resistance in a resource-constrained setting.

CASE PRESENTATION

A 60 year old man with a long standing history of hypertension presented with a 6-month history of progressive shortness of breath. Initial electrocardiogram (ECG) revealed T-wave inversion on lateral leads and echocardiogram revealed akinetic basal lateral wall and hypokinetic mid lateral wall with reduced systolic functions. An elective coronary angiography (CAG) revealed a 90% stenosis of mid left anterior descending (LAD) artery and an 80% stenosis on the proximal left circumflex artery. He underwent a successful PCI with a drug-eluting stent implantation to mid LAD. He was discharged in a stable state 48 h post revascularization with dual antiplatelet (clopidogrel and acetylsalicylic acid). Seven days later, he presented with a crushing substernal chest pain. Cardiac enzymes were elevated and ECG revealed anterior ST-elevation MI. An emergency CAG revealed a high thrombus burden with 100% occlusion of mid LAD. Following unsuccessful ballooning, intravenous and intracoronary thrombolysis with tenecteplase was given. A TIMI II flow was achieved and the patient was sent to the coronary care unit. However, 14 h later there was yet a new onset of severe chest pain. A 12-lead ECG previewed anterior ST-elevation MI and the cardiac enzymes were high. Urgent CAG revealed in-stent thrombotic total occlusion of mid LAD. A stent in stent was then implanted and TIMI III flow was restored. Clopidogrel resistance was suspected and the patient was transitioned to ticagrelol. There were no further ischemic events during the remainder of hospitalization and the patient was discharged in a hemodynamically stable state three days later. During follow-up after one and three months, he was fairly stable without any further cardiac events.

CONCLUSIONS

Owing to clopidogrel resistance, stent thrombosis in the setting of dual antiplatelet therapy compliance may occur. While in a situation of clopidogrel resistance newer and more potent antiplatelet drugs should be used, their availability and cost remains a significant barrier particularly in the developing world. Nonetheless, a high index of suspicion and timely revascularization is fundamental to restore patency of the thrombosed vessel and confer better risk-adjusted survival rates.

The Usefulness of Intracoronary Imaging in Patients with ST-Segment Elevation Myocardial Infarction

Intracoronary imaging (ICI) modalities, namely intravascular ultrasound (IVUS) and optical coherence tomography (OCT), have shown to be able to reduce major adverse cardiovascular events in patients undergoing percutaneous coronary intervention (PCI). Nevertheless, patients with ST-segment elevation myocardial infarction (STEMI) have been practically excluded from contemporary large randomized controlled trials. The available data are limited and derive mostly from observational studies. Nevertheless, contemporary studies are in favor of ICI utilization in patients who undergo primary PCI. Regarding technical aspects of PCI, ICI has been associated with the implantation of larger stent diameters, higher balloon inflations and lower residual in-stent stenosis post-PCI. OCT, although used significantly less often than IVUS, is a useful tool in the context of myocardial infarction without obstructive coronary artery disease since, due to its high spatial resolution, it can identify the underlying mechanism of STEMI, and, thus, guide therapy. Stent thrombosis (ST) is a rare, albeit a potential lethal, complication that is expressed clinically as STEMI in the vast majority of cases. Use of ICI is encouraged with current guidelines in order to discriminate the mechanism of ST among stent malapposition, underexpansion, uncovered stent struts, edge dissections, ruptured neoatherosclerotic lesions and coronary evaginations. Finally, ICI has been proposed as a tool to facilitate stent deferring during primary PCI based on culprit lesion characteristics.

Intravascular Imaging for Guiding In-Stent Restenosis and Stent Thrombosis Therapy

Advances in stent technology and the design of endovascular devices with thinner struts, anti-inflammatory and antithrombotic polymers, and better drug kinetics have enhanced the safety and efficacy of the second-generation drug-eluting stents and broadened their use in the therapy of high-risk patients and complex anatomies. However, despite these developments, in-stent restenosis and stent thrombosis remain the Achilles' heel of percutaneous coronary intervention, with their cumulative incidence reaching up to 10% at 5 years following percutaneous coronary intervention. The treatment of stent failure poses challenges and is associated with a worse prognosis than conventional percutaneous coronary intervention. Several studies have recently highlighted the value of intravascular imaging in identifying causes of stent failure, underscored its role in treatment planning, and registries have shown that its use may be associated with better clinical outcomes. The present review aims to summarize the evidence in the field; it discusses the value of intravascular imaging in identifying the mechanisms of in-stent restenosis and stent thrombosis in assessing the morphological characteristics of neointima tissue that appears to determine long-term outcomes in evaluating procedural results, and presents the findings of studies supporting its value in guiding therapy in stent failure.

Glycaemic Control in Patients Undergoing Percutaneous Coronary Intervention: What Is the Role for the Novel Antidiabetic Agents? A Comprehensive Review of Basic Science and Clinical Data

Coronary artery disease (CAD) remains one of the most important causes of morbidity and mortality worldwide, and revascularization through percutaneous coronary interventions (PCI) significantly improves survival. In this setting, poor glycaemic control, regardless of diabetes, has been associated with increased incidence of peri-procedural and long-term complications and worse prognosis. Novel antidiabetic agents have represented a paradigm shift in managing patients with diabetes and cardiovascular diseases. However, limited data are reported so far in patients undergoing coronary stenting. This review intends to provide an overview of the biological mechanisms underlying hyperglycaemia-induced vascular damage and the contrasting actions of new antidiabetic drugs. We summarize existing evidence on the effects of these drugs in the setting of PCI, addressing pre-clinical and clinical studies and drug-drug interactions with antiplatelet agents, thus highlighting new opportunities for optimal long-term management of these patients.

Balancing thrombosis and bleeding after out-of-hospital cardiac arrest related to acute coronary syndrome: A literature review

Balance between thrombosis and bleeding is now well recognized in patients treated for acute coronary syndrome, with impact on short- and long-term prognosis, including survival. Recent data suggest that patients who are resuscitated after out-of-hospital cardiac arrest related to myocardial infarction are at an even higher risk of bleeding and thrombosis than those with uncomplicated acute coronary syndrome. Delayed enteral absorption of medication due to induced hypothermia and systemic inflammation increases thrombosis risk, whereas transfemoral access site, cardiopulmonary resuscitation manoeuvres and mechanical circulatory support devices increase bleeding risk. In addition, post-resuscitation syndrome and renal or hepatic impairment are potential risk factors for both bleeding and thrombotic complications. There are currently no randomized controlled trials comparing various P₂Y₁₂ inhibitor and/or anticoagulation strategies in the setting of out-of-hospital cardiac arrest, and current practice is largely derived from management of patients with uncomplicated acute coronary syndrome. The aim of this review is therefore to describe the bleeding and thrombosis risk factors in this specific population, and to review recent data on antithrombotic drugs in this patient subset.

Intravascular Ultrasound Versus Angiography-Guided Drug-Eluting Stent Implantation: A Health Economic Analysis

BACKGROUND

There is increasing evidence that use of intravascular ultrasound (IVUS) guidance during percutaneous coronary intervention (PCI) is associated with improved clinical outcomes compared with angiography guidance alone. However, concern regarding the cost-effectiveness of IVUS has limited use of this technology worldwide. In this study, we aimed to evaluate the cost-effectiveness of IVUS-guided PCI compared with angiography-guided PCI in patients undergoing drug-eluting stent implantation.

METHODS

A decision-analytic Markov model was constructed to compare the cost-effectiveness of IVUS to angiography guidance from the Australian healthcare system perspective. Procedure-related morbidity and mortality were estimated from the literature. Costs were obtained from Australian sources. The population of interest was all-comers undergoing PCI with drug-eluting stent. Outcomes of interest included costs, life-expectancy, and quality-adjusted life years (QALYs) for both treatment groups.

RESULTS

In the base case, IVUS guidance was cost-effective compared with angiography guidance alone. With 5% annual discounting, IVUS was associated with increased lifetime costs of Australian dollars (AUD) $823 (USD $597) per person and benefits of 0.04 life years and 0.05 QALYs compared with angiography, yielding an incremental cost-effectiveness ratio of AUD $17 539 (USD $12 730) per QALY gained. Results were robust to sensitivity analyses, with IVUS being cost-effective in 99% of 10 000 Monte Carlo iterations assuming a willingness-to-pay threshold of AUD $50 000 per QALY gained. In a worst-case scenario analysis, IVUS remained the cost-effective option, with an ICER of AUD $36 651 (USD $26 601) per QALY gained. Exploratory subgroup analysis revealed that cost-effectiveness may be greatest among patients with left main and complex coronary lesions.

CONCLUSIONS

Use of IVUS guidance during PCI is likely to be cost-effective compared with angiography guidance alone among patients undergoing drug-eluting stent implantation.

Effects of electret coating technology on coronary stent thrombogenicity

Stent thrombosis (ST) is a catastrophic event and efforts to reduce its incidence by altering blood-stent interactions are longstanding. A new electret coating technology that produces long-lasting negative charge on stent surface could make them intrinsically resistant to thrombosis. We assessed the thrombogenicity of stents using an annular perfusion model with confocal microscopy, and determined the efficacy of electret coating technology to confer thrombo-resistant properties to standard stents. Using an annular perfusion chamber, Bare Metal Stent (BMS), standard uncoated DES (DES), and Electret-coated DES (e-DES) were exposed to human blood under arterial flow conditions. Deposits of fibrinogen and platelets on the stent surface were analyzed using immunofluorescence staining and confocal microscopy. Surface coverage by fibrinogen and platelets and the deposit/aggregate size were quantified using computerized morphometric analysis. The experimental methodology produced consistent, quantifiable results. Area of stent surface covered by fibrinogen and platelets and the average size of the deposits/aggregates were lowest for e-DES and highest on BMS, with DES in the middle. The size of fibrinogen-deposits showed no differences between the stents. The testing methodology used in our study successfully demonstrated that electret coating confers significant antithrombotic property to DES stents. These findings warrant confirmation in a larger study.