Effects of Intracoronary Pro-urokinase or Tirofiban on Coronary Flow During Primary Percutaneous Coronary Intervention for Acute Myocardial Infarction: A Multi-Center, Placebo-Controlled, Single-Blind, Randomized Clinical Trial

Intracoronary thrombolysis combined with drug balloon angioplasty in a young ST-segment elevation myocardial infarction patient: A case report

BACKGROUND

The combination of acute ST-segment elevation myocardial infarction (STEMI) and gastric ulcers poses a challenge to primary percutaneous coronary intervention (PPCI), particularly for young patients. The role of drug-coated balloons (DCBs) in the treatment of de novo coronary artery lesions in large vessels remains unclear, especially for patients with STEMI. Our strategy is to implement drug balloon angioplasty following the intracoronary administration of low-dose prourokinase and adequate pre-expansion.

CASE SUMMARY

A 54-year-old male patient presented to the emergency department due to chest pain on June 24, 2019. Within the first 3 minutes of the initial assessment in the emergency room, the electrocardiogram (ECG) showed significant changes. There was atrial fibrillation with ST-segment elevation. Subsequently, atrial fibrillation terminated spontaneously and reverted to sinus rhythm. Soon after, the patient experienced syncope. The ECG revealed torsades de pointes ventricular tachycardia. A few seconds later, it returned to sinus rhythm. High-sensitivity tropon in I was normal. The diagnosis was acute STEMI. Emergency coronary angiography revealed subtotal occlusion with thrombus formation in the proximal segment of the left anterior descending artery. Considering the patient's age and history of peptic ulcer disease, after the intracoronary injection of prourokinase, percutaneous transluminal coronary angioplasty and cutting balloon angioplasty were conducted for thorough preconditioning, and paclitaxel drug-eluting balloon angioplasty was performed without any stents, achieving favorable outcomes.

CONCLUSION

A PPCI without stents may be a viable treatment strategy for select patients with STEMI, and further research is warranted.

Intracoronary thrombolysis in ST-elevation myocardial infarction: a systematic review and meta-analysis

BACKGROUND

Despite restoration of epicardial blood flow in acute ST-elevation myocardial infarction (STEMI), inadequate microcirculatory perfusion is common and portends a poor prognosis. Intracoronary (IC) thrombolytic therapy can reduce microvascular thrombotic burden; however, contemporary studies have produced conflicting outcomes.

OBJECTIVES

This meta-analysis aims to evaluate the efficacy and safety of adjunctive IC thrombolytic therapy at the time of primary percutaneous coronary intervention (PCI) among patients with STEMI.

METHODS

Comprehensive literature search of six electronic databases identified relevant randomised controlled trials. The primary outcome was major adverse cardiac events (MACE). The pooled risk ratio (RR) and weighted mean difference (WMD) with a 95% CI were calculated.

RESULTS

12 studies with 1915 patients were included. IC thrombolysis was associated with a significantly lower incidence of MACE (RR=0.65, 95% CI 0.51 to 0.82, I2=0%, p<0.0004) and improved left ventricular ejection fraction (WMD=1.87; 95% CI 1.07 to 2.67; I2=25%; p<0.0001). Subgroup analysis demonstrated a significant reduction in MACE for trials using non-fibrin (RR=0.39, 95% CI 0.20 to 0.78, I2=0%, p=0.007) and moderately fibrin-specific thrombolytic agents (RR=0.62, 95% CI 0.47 to 0.83, I2=0%, p=0.001). No significant reduction was observed in studies using highly fibrin-specific thrombolytic agents (RR=1.10, 95% CI 0.62 to 1.96, I2=0%, p=0.75). Furthermore, there were no significant differences in mortality (RR=0.91; 95% CI 0.48 to 1.71; I2=0%; p=0.77) or bleeding events (major bleeding, RR=1.24; 95% CI 0.47 to 3.28; I2=0%; p=0.67; minor bleeding, RR=1.47; 95% CI 0.90 to 2.40; I2=0%; p=0.12).

CONCLUSION

Adjunctive IC thrombolysis at the time of primary PCI in patients with STEMI improves clinical and myocardial perfusion parameters without an increased rate of bleeding. Further research is needed to optimise the selection of thrombolytic agents and treatment protocols.

Urokinase-Type Plasminogen Activator Receptor (uPAR) in Inflammation and Disease: A Unique Inflammatory Pathway Activator

The urokinase-type plasminogen activator receptor (uPAR) is a unique protease binding receptor, now recognized as a key regulator of inflammation. Initially, uPA/uPAR was considered thrombolytic (clot-dissolving); however, recent studies have demonstrated its predominant immunomodulatory functions in inflammation and cancer. The uPA/uPAR complex has a multifaceted central role in both normal physiological and also pathological responses. uPAR is expressed as a glycophosphatidylinositol (GPI)-linked receptor interacting with vitronectin, integrins, G protein-coupled receptors, and growth factor receptors within a large lipid raft. Through protein-to-protein interactions, cell surface uPAR modulates intracellular signaling, altering cellular adhesion and migration. The uPA/uPAR also modifies extracellular activity, activating plasminogen to form plasmin, which breaks down fibrin, dissolving clots and activating matrix metalloproteinases that lyse connective tissue, allowing immune and cancer cell invasion and releasing growth factors. uPAR is now recognized as a biomarker for inflammatory diseases and cancer; uPAR and soluble uPAR fragments (suPAR) are increased in viral sepsis (COVID-19), inflammatory bowel disease, and metastasis. Here, we provide a comprehensive overview of the structure, function, and current studies examining uPAR and suPAR as diagnostic markers and therapeutic targets. Understanding uPAR is central to developing diagnostic markers and the ongoing development of antibody, small-molecule, nanogel, and virus-derived immune-modulating treatments that target uPAR.

Efficacy and safety of intracoronary pro-urokinase combined with low-pressure balloon pre-dilatation during percutaneous coronary intervention in patients with anterior ST-segment elevation myocardial infarction

BACKGROUND

The efficacy and safety of low-pressure balloon pre-dilatation before intracoronary pro-urokinase (pro-UK) in preventing no-reflow during percutaneous coronary intervention (PCI) remains unknown. This study aimed to evaluate the clinical outcomes of intracoronary pro-UK combined with low-pressure balloon pre-dilatation in patients with anterior ST-segment-elevation myocardial infarction (STEMI).

METHODS

This was a randomized, single-blind, investigator-initiated trial that included 179 patients diagnosed with acute anterior STEMI. All patients were eligible for PCI and were randomized into two groups: intracoronary pro-UK combined with (ICPpD group, n = 90) or without (ICP group, n = 89) low-pressure balloon pre-dilatation. The main efficacy endpoint was complete epicardial and myocardial reperfusion. The safety endpoints were major adverse cardiovascular events (MACEs), which were analyzed at 12 months follow-up.

RESULTS

Patients in the ICPpD group presented significantly higher TIMI myocardial perfusion grade 3 (TMPG3) compared to those in the ICP group (77.78% versus 68.54%, P = 0.013), and STR ≥ 70% after PCI 30 min (34.44% versus 26.97%, P = 0.047) or after PCI 90 min (40.0% versus 31.46%, P = 0.044). MACEs occurred in 23 patients (25.56%) in the ICPpD group and in 32 patients (35.96%) in the ICP group. There was no difference in hemorrhagic complications during hospitalization between the groups.

CONCLUSION

Patients with acute anterior STEMI presented more complete epicardial and myocardial reperfusion with adjunctive low-pressure balloon pre-dilatation before intracoronary pro-UK during PCI.

TRIAL REGISTRATION

2019xkj213.

Intracoronary Thrombolysis in ST-Segment Elevation Myocardial Infarction Patients Undergoing Primary Percutaneous Coronary Intervention: an Updated Meta-analysis of Randomized Controlled Trials

BACKGROUND

Primary percutaneous coronary intervention (PPCI) is the standard reperfusion treatment in ST-segment elevation myocardial infarction (STEMI). Intracoronary thrombolysis (ICT) may reduce thrombotic burden in the infarct-related artery, which is often responsible for microvascular obstruction and no-reflow.

METHODS

We conducted, according to the PRISMA statement, the largest meta-analysis to date of ICT as adjuvant therapy to PPCI. All relevant studies were identified by searching the PubMed, Scopus, Cochrane Library, and Web of Science.

RESULTS

Thirteen randomized controlled trials (RCTs) involving a total of 1876 patients were included. Compared to the control group, STEMI ICT-treated patients had fewer major adverse cardiac events (MACE) (OR 0.65, 95% CI, 0.48-0.86, P = 0.003) and an improved 6-month left ventricular ejection fraction (MD 3.78, 95% CI, 1.53-6.02, P = 0.0010). Indices of enhanced myocardial microcirculation were better with ICT (Post-PCI corrected thrombolysis in myocardial infarction (TIMI) frame count (MD - 3.57; 95% CI, - 5.00 to - 2.14, P < 0.00001); myocardial blush grade (MBG) 2/3 (OR 1.76; 95% CI, 1.16-2.69, P = 0.008), and complete ST-segment resolution (OR 1.97; 95% CI, 1.33-2.91, P = 0.0007)). The odds for major bleeding were comparable between the 2 groups (OR 1.27; 95% CI, 0.61-2.63, P = 0.53).

CONCLUSIONS

The present meta-analysis suggests that ICT was associated with improved MACE and myocardial microcirculation in STEMI patients undergoing PPCI, without significant increase in major bleeding. However, these findings necessitate confirmation in a contemporary large RCT.

Association Between Platelet Glycoprotein IIb/IIIa Inhibition and In-Hospital Outcomes in ST-Elevation Myocardial Infarction Patients Treated with Coronary Thrombus Aspiration: Findings from the CCC-ACS Project

PURPOSE

Thrombus aspiration in ST-elevation myocardial infarction (STEMI) with high thrombus burden did not improve clinical outcomes. The clinical efficacy of the bailout use of platelet glycoprotein IIb/IIIa inhibitors (GPIs) in this clinical scenario remains unknown.

METHODS

We assessed associations between GPI use and in-hospital major bleeds, ischemic events, and mortality among STEMI patients treated with percutaneous coronary intervention (PCI) and thrombus aspiration in a nationwide acute coronary syndrome registry (the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome project).

RESULTS

A total of 5896 STEMI patients who received thrombus aspiration were identified, among which 56.3% received GPI therapy. In a 1-to-1 propensity-score-matched cohort, compared with STEMI patients not treated with GPI, GPI use was associated with a 69% increase in major in-hospital bleeds, with an odds ratio (OR) of 1.69, a 95% confidence interval (CI) of 1.08 to 2.65, and a nonsignificant reduction in ischemic events (OR: 0.61, 95% CI: 0.36 to 1.06), as well as a neutral effect on mortality (OR: 0.93, 95% CI: 0.55 to 1.58). However, among patients aged < 60 years, GPI use was associated with a reduction in ischemic events (OR: 0.27, 95% CI: 0.08 to 0.98), and no significant increase in major bleeds was observed.

CONCLUSION

In a nationwide registry, routine use of GPI following thrombus aspiration was not associated with reduced in-hospital ischemic events and mortality but at the cost of increased major bleeding. However, for patients aged < 60 years, there may be a potential net benefit.

Pathophysiology and Treatment of the No-Reflow Phenomenon in ST-Segment Elevation Myocardial Infarction: Focus on Low-Dose Fibrinolysis during Primary Percutaneous Intervention

Primary percutaneous coronary intervention (PCI) is the current class I therapeutic approach to treat acute ST-elevation myocardial infarction (STEMI). While primary PCI can restore adequate flow in the infarcted artery in the majority of cases, some patients experience the 'no-reflow' phenomenon, i.e., an abnormal myocardial reperfusion occurring even after the occluded coronary artery has been opened. No-reflow occurs when microvascular obstruction arises from embolization of thrombus or components of the atheromatous plaques. These embolic materials travel downstream within the infarct-related artery at time of primary PCI, leading to compromised blood flow. Currently, no expert consensus documents exist to outline an optimal strategy to prevent or treat no-reflow. Interventional cardiologists frequently employ intracoronary adenosine, calcium channel blockers, nicorandil, nitroprusside or glycoprotein IIb/IIIa inhibitors. However, evidence suggests that these interventions consistently enhance myocardial blood flow in only a specific subset of patients experiencing no-reflow. A recent and innovative therapeutic approach gaining attention is low-dose fibrinolysis during primary PCI, which offers the potential to augment coronary flow post-myocardial revascularization.

Does Adjunctive Prophylactic Intracoronary Infusion of Low Dose Alteplase Prevent No-Reflow Phenomenon During Primary Percutaneous Coronary Intervention?

INTRODUCTION

Primary percutaneous coronary intervention (PPCI) is the gold standard approach to restore blood flow in ST-segment elevation myocardial infarction (STEMI); however, the no-reflow phenomenon as a potential complication of PPCI can worsen the outcomes. It has been hypothesized that adjunctive prophylactic intracoronary infusion of low-dose fibrinolytic might improve the PPCI outcomes; however, this theory is a matter of debate. The current study aims to investigate the value of adjunctive prophylactic intracoronary low-dose alteplase to prevent the no-reflow phenomenon in patients with STEMI.

METHOD

This case-control study was conducted on 80 STEMI patients who underwent PPCI. The patients were assigned into the case group who were intervened by 10 mg adjunctive intracoronary alteplase immediately at the end of the balloon angioplasty (n=40) and controls (n=40) who underwent conventional PPCI only. The angioplasty-associated outcomes including final TIMI score, need for no-reflow treatment, ST-segment resolution, post-PPCI complications, and death were compared between the groups.

RESULTS

Alteplase use was accompanied by significantly improved final TIMI flow scores (P-value<0.001) and fewer requirements for no-reflow treatments (P-value<0.001); however, it did not improve the ST-segment resolution (P-value=0.491). The mortality rate and post-angioplasty complications did not differ between the groups (P-value>0.05).

CONCLUSION

Based on the findings of this study, adjunctive infusion of low-dose intracoronary alteplase during PPCI could not efficiently prevent the no-reflow phenomenon. Although the final TIMI flow and need for post-stenting no-reflow treatment improved, ST-segment resolution did not occur dramatically. Given that, this approach requires further investigations and should be considered cautiously.

Safety and efficacy of intracoronary thrombolytic agents during primary percutaneous coronary intervention for STEMI

INTRODUCTION

Large thrombus burden in patients with ST elevation myocardial infarction (STEMI) is associated with higher rates of distal embolization, no-reflow phenomenon, abrupt closure, stent thrombosis, major adverse cardiovascular events (MACE), and mortality. Intracoronary (IC) thrombolytic agents are theoretically attractive as an adjunct to primary percutaneous coronary intervention (PPCI) as they activate endogenous fibrinolysis which results in degradation of the cross-linked fibrin matrix in coronary thrombus.

AREAS COVERED

We reviewed published studies reporting on intraprocedural anti-thrombus strategies used during PPCI including randomized controlled trials and observational studies.

EXPERT OPINION

Published studies are limited by small sample size and heterogeneity due to variation in indication, inclusion criteria, thrombolytic agent, dose, delivery mechanisms, antiplatelet and anticoagulant regimen, timing in regard to reperfusion, PCI techniques, and endpoints. Despite these limitations, data are consistent that IC administration of thrombolytic agents at low doses is associated with low rates of bleeding and vascular complications. While there is currently no compelling data demonstrating a benefit to the routine use of IC thrombolytic therapy in patients with STEMI, there is suggestive data that IC thrombolysis may have benefit in selected patients.

Coronary microvascular dysfunction: A review of recent progress and clinical implications

The coronary microcirculation plays a cardinal role in regulating coronary blood flow to meet the changing metabolic demands of the myocardium. Coronary microvascular dysfunction (CMD) refers to structural and functional remodeling of the coronary microcirculation. CMD plays a role in the pathogenesis of obstructive and non-obstructive coronary syndromes as well as myocardial diseases, including heart failure with preserved ejection fraction (HFpEF). Despite recent diagnostic advancements, CMD is often under-appreciated in clinical practice, and may allow for the development of novel therapeutic targets. This review explores the diagnosis and pathogenic role of CMD across a range of cardiovascular diseases, its prognostic significance, and the current therapeutic landscape.

Effects of intracoronary low-dose prourokinase administration on ST-segment elevation in patients with myocardial infarction and a high thrombus burden: a randomized controlled trial

OBJECTIVE

To evaluate the efficacy and safety of low-dose prourokinase (pro-UK) administration during primary percutaneous coronary intervention (PCI) for the treatment of acute ST-segment elevation myocardial infarction (STEMI) in patients with a high thrombus burden.

METHODS

A prospective, randomized controlled trial was conducted at the Inner Mongolia People's Hospital, China. Patients with STEMI and a high thrombus burden who underwent thrombus aspiration and primary PCI were randomly allocated to pro-UK administration or control groups. The primary endpoint was corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC).

RESULTS

There were no significant differences in the baseline demographics or clinical characteristics of the two groups. The CTFC, tissue myocardial perfusion grade, ST-segment resolution, and myocardial blush grade of the pro-UK group were significantly better than those of the control group. In addition, after 30 days of follow-up, the pro-UK group had better cardiac function and perfusion than the control group. There were no differences in the clinical outcomes or incidence of hemorrhage.

CONCLUSIONS

Intracoronary low-dose pro-UK improves myocardial perfusion and cardiac function in patients with a high thrombus burden. Major hemorrhages still occur in patients administered pro-UK, but are no more frequent.Study registration: Chinese Clinical Trial Registry (ChiCTR1900022290).

Safety and efficacy of intracoronary recombinant human prourokinase administration in patients with acute myocardial infarction and ST‑segment elevation: A meta‑analysis of randomized controlled trials

Slow blood flow or no reflow following percutaneous coronary intervention (PCI) in patients with acute ST-segment elevation myocardial infarction (STEMI) typically leads to an adverse prognosis. However, it is controversial whether to use prourokinase (Pro-UK) during PCI in patients with acute STEMI. The present meta-analysis compared the efficacy and safety of intracoronary Pro-UK administration in patients with acute STEMI. Published randomized controlled trials (RCTs) were analyzed to compare Pro-UK with non-Pro-UK treatment in patients with acute STEMI. PubMed, Cochrane Library and China National Knowledge Infrastructure were searched and meta-analysis was performed using Review Manager 5.3 software. A total of 13 RCTs were selected and 1,797 patients were considered in the meta-analysis, including 897 patients who received Pro-UK intervention and 900 patients who were in the control group. No significant heterogeneity was identified across these selected studies. Pro-UK therapy significantly decreased the incidence of major adverse cardiac events [risk ratio (RR), 0.68; 95% CI, 0.56-0.82, P<0.0001], left ventricular end-diastolic diameter [standardized mean difference (SMD), -0.26; 95% CI, -0.40 - -0.12; P=0.0003], corrected thrombolysis in myocardial infarction (TIMI) frame count [SMD, -0.45; 95% CI, -0.62 - -0.28; P<0.00001] and cardiac troponin I [SMD, -0.31; 95% CI, -0.46 - -0.17; P<0.0001]. In addition, Pro-UK administration increased TIMI grade 3 flow (RR, 1.16; 95% CI, 1.07-1.25; P=0.0003), TIMI myocardial perfusion grade 3 (RR: 1.39, 95% CI: 1.12-1.74, P=0.004), ST-segment resolution (RR, 1.23; 95% CI, 1.10-1.36; P=0.0002) and left ventricular ejection fraction (SMD, 0.38; 95% CI, 0.27-0.49; P<0.00001). No significant difference was identified in bleeding (RR, 1.12; 95% CI, 0.85-1.47; P=0.41). The present meta-analysis determined that intracoronary Pro-UK administration is efficacious and safe to decrease slow blood flow or no reflow phenomena following PCI and improve the prognosis of patients with acute STEMI.

Intracoronary artery retrograde thrombolysis combined with percutaneous coronary interventions for ST-segment elevation myocardial infarction complicated with diabetes mellitus: A case report and literature review

Background

The management of a large thrombus burden in patients with acute myocardial infarction and diabetes is still a worldwide problem.

Case presentation

A 74-year-old Chinese woman presented with ST-segment elevation myocardial infarction (STEMI) complicated with diabetes mellitus and hypertension. Angiography revealed massive thrombus formation in the mid-segment of the right coronary artery leading to vascular occlusion. The sheared balloon was placed far from the occlusion segment and urokinase (100,000 u) was administered for intracoronary artery retrograde thrombolysis, and thrombolysis in myocardial infarction (TIMI) grade 3 blood flow was restored within 7 min. At last, one stent was accurately implanted into the culprit’s vessel. No-reflow, coronary slow flow, and reperfusion arrhythmia were not observed during this process.

Conclusion

Intracoronary artery retrograde thrombolysis (ICART) can be effectively and safely used in patients with STEMI along with diabetes mellitus and hypertension, even if the myocardial infarction exceeds 12 h (REST or named ICART ClinicalTrials.gov number, ChiCTR1900023849).