**1.1 Extent of disease**

Cardiovascular atherosclerosis is the most common disease in the industrial countries. In the United States of America more than 1 million patients every year are admitted to the coronary care unit with suspected acute myocardial infarction (Yusuf et al, 2004; American Heart Association, 2007). The incidence of acute myocardial infarction in USA is 865000, 565000 of them new infarctions annually. In Europe, the situation is similar to the USA, however in northern countries the incidence is higher than in southern countries (Lopez et al, 2006). In the emerging market economies in Eastern Europe, higher cardiovascular mortality is found. The burden of cardiovascular and coronary heart disease in developing countries is approaching that in developed countries. Thus the problem is a worldwide problem and international joint efforts are needed in order to treat this still prevalent disease.

Mortality of acute myocardial infarction is decreasing steadily. This decrease is related to reduction in the prevalence of disease in some countries, improvement of primary prevention and secondary prevention as well as treatment of the acute event (Hunink et al, 1997; Cooper et al, 2000).

#### **1.2 Contemporary treatment**

Primary percutaneous coronary intervention (PCI) is the treatment of choice in acute ST elevation myocardial infarction (Grines et al, 1993; Zijlstra et al, 1993; GUSTO, 1997; De Luca et al, 2004).The objective of primary PCI is to restore myocardial perfusion in the coronary bed distal to the occluded culprit artery. The TIMI classification (Chesebro et al, 1987) and myocardial blush grades (van't Hof, 1998; Gibson et al, 2000; Stone et al, 2002) used to assess epicardial coronary artery flow and myocardial perfusion after primary PCI

Effects of Eptifibatide on the Microcirculation After Primary Angioplasty in

**1.5 Possible solution for coronary microvascular dysfunction** 

however, an experienced operator is essential.

microcirculation.

**2. Methods** 

**2.1 Primary PCI** 

12 months after the procedure.

elevation myocardial infarction.

Acute ST-Elevation Myocardial Infarction: A Trans-Thoracic Coronary Artery Doppler Study 61

enhance the detection rate of coronary velocities (Abizaid et al, 1998; Caiati et al, 1999),

Sampling of blood velocities in the left anterior descending coronary artery is successful almost in all patients. The advantages of Doppler sampling of coronary artery blood velocities is that it is non-invasive and can be repeated easily in the coronary care unit. As we demonstrated recently using transthoracic Doppler, the function of the microcirculation is dynamic and changes after primary angioplasty (Sharif et al, 2008; 2010). After primary coronary intervention in acute myocardial infraction the microcircirculation may improve or deteriorate. Therefore, transthoracic Doppler sampling of coronary artery velocities is even more important than other methods for the evaluation of the function of coronary

After having the epicardial coronary artery treated and well open, according to the mechanisms of microcirculatory dysfunction, platelet micro-emboli and changes in platelet activity may have an impact on myocardial perfusion. Therefore, in the present study we examine the effects adjuvant treatment with glycoprotein 2b3a receptor blockers on the function of the microcirculation after primary angioplasty in the setting of acute anterior ST-

Forty five consecutive patients with acute ST elevation anterior myocardial infarction undergoing primary PCI were enrolled in the study. All fulfilled the following criteria: 1) First anterior wall ST segment elevation myocardial infarction (STEMI). 2) Primary PCI within 12 hours of the onset of symptoms. 3) Routine informed consent to perform primary PCI. Anterior STEMI was defined as continuous chest pain for at least 30 minutes and ST elevation of at least 2.0mm in ≥2 contiguous precordial ECG leads. Exclusion criteria included one of the following clinical or angiographic findings: Prior bypass surgery,

Primary PCI was performed in standard fashion. All subjects were treated with oral clopidogral (600 mg) and aspirin (300 mg) in the emergency department. Thirty one patients were treated with an intravenous bolus injection of heparin (50-70 U/Kg) to achieve coagulation time of ≥ 250msec, Fourteen patients were treated before angioplasty with intravenous eptifibatide as 2 boluses of 180ug/kg, ten minutes apart, and a maintenance infusion at a rate of 2ug/kg/min for 24 hours, and 500 units heparin/hour. Coronary angiography and primary PCI were performed subsequently. Bare metal stents were deployed by high-pressure implantation techniques. Low magnification angiogram at either the right 30 º or 90 º lateral projections with prolonged cine was performed to optimize myocardial blush grade (MBG) documentation at the end of the intervention as previously described ( van't Hof et al, 1998). All patients were treated with clopidogrel and aspirin for

previous anterior STEMI, significant left main artery disease, failed primary PCI.

predict outcome after the procedure. However, the TIMI flow and myocardial blush grades are semi-quantitative, invasive, not easily repeatable, and do not reflect subsequent events and processes at the level of the coronary artery and microcirculation. Thus, even with successful primary PCI and the high rate of patency of the culprit artery, left ventricular functional recovery is limited and not well predicted (Stone et al, 1997; Zijlstra et al, 1997).
