Intracoronary Versus Intravenous Low-Dose Tirofiban in Patients With ST-Elevation Myocardial Infarction: A Meta-Analysis of Randomised Controlled Trials

BACKGROUND

This meta-analysis aimed to evaluate the effects of intracoronary (IC) low-dose tirofiban versus intravenous (IV) administration on clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS

All published randomised controlled trials (RCTs) comparing the effects of IC low-dose tirofiban (a bolus of ≤10 ug/kg) versus IV administration in patients with STEMI were identified by searching PubMed, EMBASE, Cochrane Library, and ISI Web of Science from inception to June 2023, with no language restriction. The risk ratio (RR) with 95% confidence intervals (CI) and the weighted mean difference (WMD) with 95% CI were calculated.

RESULTS

Eleven RCTs involving 1,802 patients were included. Compared with the IV group, IC low-dose tirofiban was associated with improved major adverse cardiac events rate (RR 0.595, 95% CI 0.442-0.802; p=0.001), left ventricular ejection fraction (WMD 1.982, 95% CI 0.565-3.398; p=0.006), thrombolysis in myocardial infarction (TIMI) flow grade (RR 1.065, 95% CI 1.004-1.131; p=0.037), and TIMI myocardial perfusion grade (RR 1.194, 95% CI 1.001-1.425; p=0.049). The two groups had no significant difference in bleeding events (RR 0.952, 95% CI 0.709-1.279; p=0.745).

CONCLUSIONS

Intracoronary low-dose tirofiban administration may be a safe and effective alternative to IV administration in STEMI patients.

What do we know about platelets in myocardial ischemia-reperfusion injury and why is it important?

Myocardial ischemia-reperfusion injury (MIRI), the joint result of ischemic injury and reperfusion injury, is associated with poor outcomes in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention. Accumulating evidence demonstrates that activated platelets directly contribute to the pathogenesis of MIRI through participating in the formation of microthrombi, interaction with leukocytes, secretion of active substances, constriction of microvasculature, and activation of spinal afferent nerves. The molecular mechanisms underlying the above detrimental effects of activated platelets include the homotypic and heterotypic interactions through surface receptors, transduction of intracellular signals, and secretion of active substances. Revealing the roles of platelet activation in MIRI and the associated mechanisms would provide potential targets/strategies for the clinical evaluation and treatment of MIRI. Further studies are needed to characterize the temporal (ischemia phase vs. reperfusion phase) and spatial (systemic vs. local) distributions of platelet activation in MIRI by multi-omics strategies. To improve the likelihood of translating novel cardioprotective interventions into clinical practice, basic researches maximally replicating the complexity of clinical scenarios would be necessary.

NT-proBNP level before primary PCI and risk of poor myocardial reperfusion: Insight from the On-TIME II trial

BACKGROUND

N-terminal fragment of the brain natriuretic peptide prohormone (NT-proBNP), a marker for neurohumoral activation, has been associated with adverse outcome in patients with myocardial infarction. NT-proBNP levels may reflect extensive ischemia and microvascular damage, therefore we investigated the potential association between baseline NT-proBNP level and ST-resolution (STR), a marker of myocardial reperfusion, after primary percutaneous coronary intervention (pPCI).

METHODS

we performed a post-hoc analysis of the On-TIME II trial (which randomized ST-elevation myocardial infarction (STEMI) patients to pre-hospital tirofiban administration vs placebo). Patients with measured NT-proBNP before angiography were included. Multivariate logistic-regression analyses was performed to investigate the association between baseline NTproBNP level and STR one hour after pPCI.

RESULTS

Out of 984 STEMI patients, 918 (93.3%) had NT-proBNP values at baseline. Patients with STR <70% had higher NT-proBNP values compared to patients with complete STR (>70%) [Mean ±SD 375.2 ±1021.7 vs 1007.4 ±2842.3, Median (IQR) 111.7 (58.4-280.0) vs 168.0 (62.3-601.3), P <.001]. At multivariate logistic regression analysis, independent predictors associated with higher risk of poor myocardial reperfusion (STR <70%) were: NT-proBNP (OR 1.17, 95%CI 1.04-1.31, P = .009), diabetes mellitus (OR 1.87, 95%CI 1.14-3.07, P = .013), anterior infarct location (OR 2.74, 95% CI 2.00-3.77, P <.001), time to intervention (OR 1.06, 95%CI 1.01-1.11, P = .021), randomisation to placebo (OR 1.45, 95%CI 1.05-1.99, P = .022).

CONCLUSIONS

In STEMI patients, higher baseline NT-proBNP level was independently associate with higher risk of poor myocardial reperfusion, supporting the potential use of NT-proBNP as an early marker for risk stratification of myocardial reperfusion after pPCI in STEMI patients.

Safety and efficacy of Tirofiban in STEMI-patients

BACKGROUND

Tirofiban is recommended as bail out therapy in patients with ST-elevation myocardial infarction (STEMI). However, evidence regarding safety and efficacy of tirofiban is unclear. Tirofiban has been shown to improve ST-resolution, to decrease infarct size (IS) and to reduce incidence of major adverse cardiac and cerebrovascular events (MACCE). However, bleeding is enhanced in tirofiban treated patients. In this study, we aim to investigate efficacy and safety of Tirofiban in STEMI-patients.

METHODS

610 STEMI patients were analyzed. MACCE (death, myocardial infarction [MI], stroke) and TIMI bleeding events were registered during hospital course and 12 month follow-up.

RESULTS

Tirofiban patients were slightly younger (tirofiban 63 ± 13 years vs. control 65 ± 14 years; p = 0.04). They had higher peak-high-sensitive troponin T [Hs-TnT] (tirofiban 6561 ± 11,065 vs. control 4594 ± 11,200, p-value = 0.047) and peak-creatine kinase [CK] (tirofiban 2742 ± 5097 vs. control 1416 ± 2160, p-value < 0.0001). Percutaneous coronary intervention (PCI) was more complex in tirofiban treated patients as radiation time (tirofiban 18 ± 15 vs. control 14 ± 13; p-value = 0.02) and use of contrast agent (tirofiban 240 ± 106 vs. control 209 ± 99; p-value = 0.01) was higher in tirofiban patients. However, there were no differences in MACCE (HR 0.877, 95% CI 0.62-1.25, p = 0.47) and bleeding (major: HR 1.494, 95% CI 0.65-3.44, p = 0.34; minor: HR 1.294, 95% CI 0.67-2.52, p = 0.45).

CONCLUSION

MACCE and bleeding events were similar. However, PCI was more complex and infarcts larger in tirofiban treated patients.

Efficacy and safety of quadruple therapy including tirofiban in the treatment of Chinese NSTE-ACS patients failing to receive timely percutaneous coronary intervention

Background

Although it has been shown to be superior to simple antithrombotic drug therapy, most patients are unable to receive timely percutaneous coronary intervention (PCI) and are treated with conventional triple antithrombotic therapy (aspirin, clopidogrel, low-molecular-weight heparin). Here, we evaluate the efficacy and safety of adding low-dose tirofiban to this regimen.

Methods

A total of 1,783 patient records (unable to receive PCI) indicating non-ST-segment elevation acute coronary syndrome (NSTE-ACS) were included. A total of 882 received conventional triple antithrombotic therapy; 901 received quadruple antithrombotic therapy. Efficacy was evaluated in terms of major adverse cardiovascular event (MACE) parameters. Safety was evaluated based on the occurrence of bleeding events. Data were collected over a 6-month period post treatment.

Results

The rate of occurrence of MACE was significantly lower in the quadruple antithrombotic group (10.5% versus 14.1% at 6 months, P=0.02). The log-rank test showed improved survival in the quadruple antithrombotic group. Total bleeding events were higher in the quadruple antithrombotic group (9.7%) than in the triple antithrombotic group (7.1%) (P=0.04); however, this may be attributed to increased clinically insignificant minor bleeding events.

Conclusion

Quadruple antithrombotic therapy demonstrated a superior alternative for the treatment of high-risk NSTE-ACS patients failing to receive PCI.

Comparison of primary coronary percutaneous coronary intervention between Diabetic Men and Women with acute myocardial infarction

OBJECTIVE

This study aimed to explore the short-term efficacy and safety of primary percutaneous coronary intervention (PCI) in female diabetic patients complicated with acute myocardial infarction (AMI).

METHODS

A total of 169 diabetic patients with AMI who underwent primary PCI were selected and divided into group A (52 females) and group B (117 males). The clinical data, characteristics of coronary artery lesions, lengths of hospital stay, and incidences of complications were then compared between two groups.

RESULTS

The average age, history of hyperlipidemia, double branch lesions, triple branch lesions, and left main lesions were significantly higher in group A than in group B (P < 0.05). Smoking history, PCI history, and pre-infarction angina were distinctly lower in group A than in group B (P < 0.05). Thrombolysis in myocardial infarction 3 (TIMI3) flow and TIMI myocardial perfusion grade 3 (TMPG3) after PCI were markedly lower in group A than in group B (P < 0.001). Group A had a higher incidence of complications, such as severe arrhythmia, cardiac function Killip III/IV, cardiogenic shock, major, moderate and mild bleed event, as well as a 30-day mortality rate, compared with group B (P < 0.05).

CONCLUSION

In summary, our study demonstrated that female diabetic patients with AMI had lower TIMI3 flow and TMPG3 following PCI than male patients, while there was higher incidence of complications and 30-day mortality rate. Therefore, more attention should be paid to the therapy of diabetic women with acute myocardial infarction as well as the control of risk factors.

Effects of baseline coronary occlusion and diabetes mellitus in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

Several studies have highlighted the prognostic role of preprocedural Thrombolysis In Myocardial Infarction (TIMI) flow in the infarct-related artery (IRA) in patients with ST-segment elevation myocardial infarction (STEMI). However, the impact of preprocedural IRA occlusion in patients with diabetes with STEMI has been insufficiently studied. The aim of this study was to evaluate the effects of baseline IRA occlusion and diabetic status in patients with STEMI who underwent primary percutaneous coronary intervention by using data from a pooled analysis of randomized trials comparing intracoronary with intravenous abciximab bolus administration. A total of 3,046 patients with STEMI who underwent primary percutaneous coronary intervention were included. Diabetes was present in 578 patients (19%). The primary outcome was mortality after a median follow-up period of 375 days. Secondary end points were reinfarction and stent thrombosis. In patients without diabetes, IRA occlusion versus no occlusion was not associated with increased rates of mortality (4.3% vs 2.7%, p = 0.051) and reinfarction (3.3% vs 2.5%, p = 0.33). Patients with diabetes with IRA occlusion compared with those without occlusion showed higher rates of mortality (10.6% vs 4.6%, p = 0.01) and reinfarction (5.6% vs 2.1%, p = 0.03). Baseline IRA occlusion increased the rate of stent thrombosis in the nondiabetic (2.1% vs 1.0%, p = 0.04) and diabetic (3.2% vs 0.8%, p = 0.05) cohorts. Interaction analysis demonstrated that the risk for death and reinfarction was significantly increased when diabetes and IRA occlusion occurred concomitantly. In conclusion, patients with STEMI with diabetes and baseline IRA occlusion had disproportionately higher rates of death and reinfarction. Preprocedural IRA occlusion increased the risk for stent thrombosis, irrespective of diabetic status.

Current state of clinical translation of cardioprotective agents for acute myocardial infarction

There is continued interest in the concept of limiting myocardial infarct size with adjunctive agents administered along with reperfusion injury; however, there remains considerable controversy in the literature. The purpose of this article is to review the medical literature on clinical trials performed during the past 3 years that have attempted to reduce myocardial infarct size by administration of adjunctive therapies along with reperfusion therapy. A PubMed-driven literature search revealed a host of clinical trials focusing on the following prominent types of therapies: endogenous conditioning (postconditioning and remote ischemic conditioning); rapid cooling; pharmacological therapy (cyclosporine, abciximab, clopidogrel, tirofiban, erythropoietin, thrombus aspiration, adenosine, glucose-insulin-potassium, statins, antidiabetic agents, FX06, iron chelation, and ranolazine). Although there remains some controversy, quite a few of these studies showed that adjunctive therapy further reduced myocardial infarct size when coupled with reperfusion. Antiplatelet agents are emerging as some of the newest agents that seem to have cardioprotective capabilities. Postconditioning has become a bit more controversial in the clinical literature; remote conditioning, early and rapid cooling, adenosine, and ranolazine are intriguing therapies deserving of larger studies. Certain agents and maneuvers, such as erythropoietin, protein kinase C δ inhibitors, iron chelation, and intra-aortic balloon counterpulsation, perhaps should be retired. The correct adjunctive therapy administered along with reperfusion has the capability of further reducing myocardial injury during ST-segment-elevation myocardial infarction.