Clinical Trial: Ticagrelor and Clopidogrel on Reperfusion in Patients With AMI

Study Status: Completed
Recruit Status: Unknown status
Study Type: Interventional

Official Title: Comparison of Ticagrelor and Clopidogrel on Reperfusion in Patients With AMI Undergoing PPCI Evaluated by SPECT

Brief Summary:

The patients with acute myocardial infarction (AMI) present high mortality and morbidity rate,even treated with stenting in the blocked heart vessels.

The appearance of no-reflow is common after re-opening of the blocked vessel. The no-reflow were commonly attributed to tiny blockage in coronary micro-vasculature by thrombus and spasm of the micro-vessel during stenting.

An agent with more effective anti-clotting and micro-vessel dilation would be helpful to solve the issue of no-reflow. Ticagrelor was demonstrated to be a potent platelet inhibitor and a potent micro-vessel dilator which can influence metabolism of adenosine, a endogenous potent small vessel dilator.

This study is to test the effectiveness of ticagrelor on improving reperfusion and minimizing the myocardial infarct size after PPCI in patients with AMI.


Detailed Summary:

The patients with acute myocardial infarction (AMI) present high mortality and morbidity rate, and also have malignant prognosis even if they could survive. The mortality and prognosis has been improved markedly because of the treatment with primary percutaneous coronary intervention (PPCI). However, the issue of no-reflow after revascularization has not been solved yet. The mechanisms of no-reflow in human being were regarded mainly as micro-embolism in coronary micro-circulation with thrombus or debris from atherosclerotic plaque, coronary micro-vasculature spasm and other conditions.

Therefore, an agent with potent antithrombotic and micro-vasculature dilation function would be more effective on prevention of no-reflow after coronary revascularization. Ticagrelor was demonstrated to be a potent platelet inhibitor and a potent micro-vessel dilator which can influence metabolism of adenosine.

Ticagrelor can inhibit adenosine uptake in vitro and subsequently augments cardiac blood flow in a canine model of reactive hypoxia- or adenosine-induced blood flow increases. In a dog coronary thrombosis model, ticagrelor blocks ADP-induced platelet activation and aggregation; prevents platelet-mediated thrombosis; prolongs reperfusion time and reduces re-occlusion and cyclic flow variation; and significantly decreases infarct size and rapidly restores myocardial tissue perfusion. These findings suggest that ticagrelor may have additional benefits in patients with acute coronary syndrome beyond inhibition of platelet aggregation, which is advantageous to the dilation of microcirculation and improvement of myocardial perfusion. AMISTAD study shows that: adenosine reperfusion therapy can reduce 33% of the infarction area assessed by single-photon emission computed tomography (SPECT) detection. AMISTAD- 2 study showed that: adenosine e
Sponsor: First Hospital of China Medical University

Current Primary Outcome: myocardial infarcted size [ Time Frame: 1 week ]

To evaluate the infarcted size on Day 7 after PPCI by SPECT.


Original Primary Outcome: Same as current

Current Secondary Outcome: elevated ST segment resolution [ Time Frame: 1 hour and 24 hours ]

To observe the elevated ST segment resolution at 1 h and 24 h after PPCI;


Original Secondary Outcome: Same as current

Information By: First Hospital of China Medical University

Dates:
Date Received: September 4, 2014
Date Started: December 2014
Date Completion: December 2016
Last Updated: September 5, 2014
Last Verified: September 2014