Role of thrombolysis in reperfusion therapy for management of AMI: Indian scenario

Therapeutic management of ischemic stroke

Stroke is the third leading cause of years lost due to disability and the second-largest cause of mortality worldwide. Most occurrences of stroke are brought on by the sudden occlusion of an artery (ischemic stroke), but sometimes they are brought on by bleeding into brain tissue after a blood vessel has ruptured (hemorrhagic stroke). Alteplase is the only therapy the American Food and Drug Administration has approved for ischemic stroke under the thrombolysis category. Current views as well as relevant clinical research on the diagnosis, assessment, and management of stroke are reviewed to suggest appropriate treatment strategies. We searched PubMed and Google Scholar for the available therapeutic regimes in the past, present, and future. With the advent of endovascular therapy in 2015 and intravenous thrombolysis in 1995, the therapeutic options for ischemic stroke have expanded significantly. A novel approach such as vagus nerve stimulation could be life-changing for many stroke patients. Therapeutic hypothermia, the process of cooling the body or brain to preserve organ integrity, is one of the most potent neuroprotectants in both clinical and preclinical contexts. The rapid intervention has been linked to more favorable clinical results. This study focuses on the pathogenesis of stroke, as well as its recent advancements, future prospects, and potential therapeutic targets in stroke therapy.

Correlations between Cardiovascular Risk Factors and Ventricular Arrhythmias Following Primary Percutaneous Coronary Intervention in Patients with ST-Elevation Myocardial Infarction

Background

Ventricular arrhythmias (VAs), which result from acute myocardial infarction and revascularization, are preventable causes of sudden cardiac death. This study aimed to determine the incidence, types, and risk factors of VAs in patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention (PCI).

Methods

This cross-sectional study was conducted at the cardiology department of a tertiary care cardiac center in Zanjan, Iran. All the patients were monitored during hospitalization, and the incidence of cardiac arrhythmias and the outcomes were recorded.

Results

Among 315 patients, the mean age was 62.14±10.11 years, and 76.2% were male. Male gender was significantly associated with VA occurrence (P=0.038). Among the patients, 50.5% had VAs, of which 26.4% were sustained ventricular tachycardia (sustained VT) and ventricular fibrillation (VF). Sustained VT and VF, but not total arrhythmias, were more common in anterior infarctions. Most arrhythmias occurred during the first 12 hours, and frequent premature ventricular contractions (43.3%) and idioventricular rhythm (20.1%) were the most common. A history of PCI and coronary artery bypass grafting (CABG) was associated with substantially reduced arrhythmias (P=0.017 and P=0.013, respectively). However, cardiovascular risk factors exerted no statistically significant effects on the VA type.

Conclusion

Approximately half of our patients experienced reperfusion-induced VAs. Overall, gender and a history of PCI and CABG were significantly associated with VA occurrence. Therefore, males and patients without a positive history of PCI and CABG should receive antiarrhythmic drugs as a precaution.

Pathophysiology of streptokinase-induced hypotension in acute myocardial infarction: a systematic review of clinical evidence

Introduction

Despite the common occurrence of streptokinase-induced hypotension among patients with acute myocardial infarction, the underlying pathophysiology remains obscure and poorly understood. Our study aimed to pool clinical evidence on the potential mechanism of streptokinase-induced hypotension through a systematic review of the literature.

Material and methods

We conducted literature search from Medline, Scopus and Web of Science on clinical studies related to streptokinase-induced hypotension.

Results

Our search yielded 972 citations. After removal of duplicates, 878 articles were screened for eligibility, of which 856 papers were excluded due to various reasons. Of the remaining 22 articles retrieved with full texts, eight relevant articles were selected for final analysis. Three themes emerged as the proposed mechanisms of streptokinase-induced hypotension, including (i) reduction in total peripheral resistance, (ii) complement activation, and (iii) dismissal of hypotheses involving other intermediaries.

Conclusions

Our findings suggest that the underlying mechanism of streptokinase-induced hypotension lies primarily in the reduction in total peripheral resistance.

Correlates of Residual Thrombus Burden in Successfully Thrombolysed Patients of ST-Elevation Myocardial Infarction Receiving Dual Anti-Platelet Therapy

Background

Variable residual thrombus ranging from minimal to a large thrombus is seen in the culprit vessel after successful thrombolysis in ST-elevation myocardial infarction (STEMI). Factors associated with residual thrombus in thrombolysed patients are poorly understood. The objective of our study was to determine the correlates of residual thrombus burden in successfully thrombolysed STEMI patients receiving dual antiplatelet therapy.

Methods

In this prospective observational study of 60 successfully thrombolysed STEMI patients receiving dual antiplatelet therapy, various clinical and coronary angiographic features like residual thrombus burden, residual stenosis, and thrombolysis in myocardial infarction (TIMI) flow grade in the infarct-related artery were evaluated.

Results

Out of 60 patients, 49 and 11 patients, respectively, had low and high thrombus burden. Thirty-seven (75.5%) patients amongst low-grade thrombus had TIMI 3 flow, whereas seven (63.6%) amongst high thrombus burden had TIMI 2 flow indicating an association between residual thrombus burden and TIMI flow grade, which was statistically significant (p=0.009). Further, amongst the 39 patients who were 45 years old, a statistically significant association of age and residual stenosis (p = 0.039) was observed.

Conclusion

In successfully thrombolysed STEMI patients receiving dual antiplatelet therapy, there is an inverse correlation between residual thrombus burden and TIMI flow grade with high-grade residual thrombus associated with more frequent low TIMI flow. Further, significant residual stenosis is more common in patients older than 45 years of age, underscoring the necessity for invasive evaluation after successful thrombolysis.

Bacterial staphylokinase as a promising third-generation drug in the treatment for vascular occlusion

Vascular occlusion is one of the major causes of mortality and morbidity. Blood vessel blockage can lead to thrombotic complications such as myocardial infarction, stroke, deep venous thrombosis, peripheral occlusive disease, and pulmonary embolism. Thrombolytic therapy currently aims to rectify this through the administration of recombinant tissue plasminogen activator. Research is underway to design an ideal thrombolytic drug with the lowest risk. Despite the potent clot lysis achievable using approved thrombolytic drugs such as alteplase, reteplase, streptokinase, tenecteplase, and some other fibrinolytic agents, there are some drawbacks, such as high production cost, systemic bleeding, intracranial hemorrhage, vessel re-occlusion by platelet-rich and retracted secondary clots, and non-fibrin specificity. In comparison, bacterial staphylokinase, is a new, small-size plasminogen activator, unlike bacterial streptokinase, it hinders the systemic degradation of fibrinogen and reduces the risk of severe hemorrhage. A fibrin-bound plasmin-staphylokinase complex shows high resistance to a₂-antiplasmin-related inhibition. Staphylokinase has the potential to be considered as a promising thrombolytic agent with properties of cost-effective production and the least side effects.

A new cooperative approach for ST-elevation myocardial infarction patients to receive timely and effective percutaneous coronary reperfusion in China

Background

Acute myocardial infarction (AMI) is the most serious type of coronary heart disease. However, less than 30% of these patients have been treated effectively in China. Delayed treatment is a leading cause. This study aimed to evaluate a new regional cooperative model for improving the first medical contact-to-device time and the therapeutic effects on AMI patients.

Methods

A retrospective analysis of 458 ST-elevation myocardial infarction (STEMI) patients was performed. Patients were divided into two groups in terms of before or after the model were implemented. First medical contact-to-device time (FMC2D), Door to device time (D2D), referral time, cardiac functions, mean cost, days of hospitalization, and major adverse cardiac events (MACE) were analyzed.

Results

The mean FMC2D time, D2D time and referral time of the model group were significantly lower than the control group. The left ventricular ejection fraction of the model group increased but the left ventricular end-diastolic dimension decreased compared with the control group at 6 months after discharge. These results also showed that mean costs and days of hospitalization were reduced. The MACE rate was reduced in the model group.

Conclusions

These results suggested that the new model decreased the FMC2D time, which could improve the cardiac function and therapeutic effect of STEMI patients as well as decreased the financial burden.