Recent Advances in Blood Cell-Inspired and Clot Targeted Thrombolytic Therapies

Myocardial infarction, stroke, and pulmonary embolism are all deadly conditions associated with excessive thrombus formation. Standard treatment for these conditions involves systemic delivery of thrombolytic agents to break up clots and restore blood flow; however, this treatment can impact the hemostatic balance in other parts of the vasculature, which can lead to excessive bleeding. To avoid this potential danger, targeted thrombolytic treatments that can successfully target thrombi and release an effective therapeutic load are necessary. Because activated platelets and fibrin make up a large proportion of clots, these two components provide ample opportunities for targeting. This review will highlight potential thrombus targeting mechanisms as well as recent advances in thrombolytic therapies which utilize blood-cells and clotting proteins to effectively target and lyse clots.

Best Practices in Pharmacotherapy for Acute Coronary Syndromes

Numerous advances have been made in the therapy of acute coronary syndromes. Despite these advances, acute coronary syndromes still cause significant morbidity and mortality. Decisions as to the best therapy vary depending on other patient factors, such as age, need for chronic anticoagulation, tolerability of medications, and the degree of myocardial damage. Recent evidence suggests that a shorter duration of therapy may be beneficial in decreasing bleeding events without compromising benefits of preventing ischemic complications. For those who have an indication for chronic anticoagulation, less intensive therapy may also be beneficial, again without increasing ischemic complications. Data regarding agents that inhibit the renin–angiotensin–aldosterone system are available and these data are reviewed. Knowledge of the pharmacology, potency, and pharmacokinetics of drugs, as well as adverse drug events, may direct clinicians in choosing the optimal pharmacotherapy strategy for their patients.

Evaluation of Tpeak to end/QT and Tpeak to end/QTc ratios in patients with STEMI undergoing percutaneous intervention vs. thrombolytic therapy

INTRODUCTION

The patients with ST-segment Elevation Myocardial Infarction (STEMI) are significantly at increased risk of arrhythmia. Repolarization of myocardium has been evaluated by a series of electrical parameters including T wave peak to T wave end (Tp-Te) and Tp-Te/QT ratio. Which were compared with survival outcomes between two groups of STEMI patients treated with Primary Percutaneous Coronary Intervention (PPCI) and recombinant Tissue Plasminogen Activator (r-TPA).

METHODS

In this prospective study, 188 patients with STEMI were included in the study. 12‑Lead ECGs were obtained from all patients on time of admission and after 24 h after treatment. After dividing the patients into two groups based on their type of treatment (PPCI or r-TPA), The Tp-Te/QT and Tp-Te/QTc ratios were calculated using ECG records. The survival outcomes were compared between two groups.

RESULTS

95 patients (50.5%) underwent PPCI and 93 patients (49.5%) received r-TPA. Tp-Te/QT and Tp-Te/QTc ratios after administration of the treatments were significantly decreased in both groups (P-value = .001) with lower Tp-Te/QT and Tp-Te/QTc ratios in PPCI group (P-value = .001). 7 patients in PPCI group (7.3%) and 16 patients in r-TPA group (17.2%) were died during their hospitalization period (P-value = .04). The best combination of sensitivity and specificity of post treatment Tp-Te/QT ratio was at cutoff points of 29.4 with 82% sensitivity and 83% specificity.

CONCLUSION

Our study demonstrated that Tp-Te/QT and Tp-Te/QTc ratios decrease significantly after both PPCI and r-TPA therapies, but with PPCI these indexes decrease more than r-TPA, resulting a better survival outcome in patients with STEMI.

A review of current agents for anticoagulation for the critical care practitioner

There has been a tremendous boom in the arena of anticoagulant therapy recently. Although the indications for these agents reside in the noncritical care environment, over time, the impact of these agents have infiltrated the critical care environment particularly due to devastating complications with associated use. With so many newer agents on the market or coming down the pipeline, it is easy to become overwhelmed. It is important that the critical care practitioner does not ignore these agents but becomes familiar with them to better prepare for the management of patients on one or more anticoagulant agents in the intensive care unit. To equip the critical care practitioners with the knowledge about commonly used anticoagulants, we provide an extensive review of the pharmacology, indications, and adverse effects related to these agents as well as suggestions on preventing or managing complications.

Intracranial haemorrhage 4 days after receiving thrombolytic therapy in a young woman with myocardial infarction

Intracranial haemorrhage is a known complication after fibrinolytic therapy and occurs usually in the first 24 h. We report a 35-year-old woman who presented with severe central chest pain and she was diagnosed as anterior ST elevation myocardial infarction. She was given fibrinolytic therapy with Tenecteplase. She responded well to the treatment with a decrease in the intensity of chest pain and resolution of the ST segment elevation. She was taken for coronary angiogram the next day, which revealed an occlusion of the left anterior descending (LAD) artery, and stenting of LAD was carried out. Four days later, she developed severe headache, confusion, slurring of speech and right haemiparesis. CT brain revealed intracerebral haemorrhage and she was referred to an neurosurgeon who advised for conservative management. Her condition gradually improved with physiotherapy and was discharged home with no marked functional impairment.

Efficacy, safety, and cost of thrombolytic agents for the management of dysfunctional hemodialysis catheters: a systematic review

Approximately 100,000 patients begin hemodialysis each year in the United States. Although an arteriovenous fistula or graft is the preferred method for long-term vascular access during hemodialysis, as these types of vascular access are the most reliable, approximately 30% of patients require the use of catheters to continue hemodialysis. Tunneled, cuffed hemodialysis catheters are discouraged for permanent vascular access because of their high rates of infection, morbidity and mortality, and thrombotic and technical complications. These catheters have a short functional life span and require medical intervention, often thrombolytic therapy, to treat the catheter malfunction. No thrombolytic agent is specifically indicated for the management of occluded hemodialysis catheters. Thus, we performed a systematic review to critically evaluate all available studies that examined the efficacy, safety, and cost of thrombolytic therapy for the management of dysfunctional hemodialysis catheters. Studies were included if they reported efficacy in a specific proportion of affected dysfunctional hemodialysis catheters; reported the proportion of patients experiencing an adverse outcome (especially bleeding); and described the type of catheter used, dose of thrombolytic agent, administration protocol, dwell time, definition of treatment success, time to follow-up for study end points, and sample size. Eighteen studies met the inclusion criteria. The mean ± SD success rate in clearing dysfunctional hemodialysis catheters was greatest with reteplase at 88 ± 4%, followed by alteplase at 81 ± 37% and tenecteplase at 41 ± 5%. Adverse effects associated with the use of these thrombolytic agents administered at low doses were extremely rare. No serious adverse bleeding events attributed to thrombolytic therapy were reported in any of the trials. Aliquotted reteplase from vials for intravenous use was the least costly thrombolytic agent. Thus, at centers that use high volumes of thrombolytics for dysfunctional hemodialysis catheters, reteplase is the thrombolytic agent of choice.