Comparative efficacy of primary angioplasty with stent implantation and thrombolysis in restoring basal coronary artery flow in acute ST segment elevation myocardial infarction: quantitative assessment using the corrected TIMI frame count

The Effects of Percutaneous Coronary Intervention on the Flow in Acute Coronary Syndrome Patients-Geometry in Focus

Evaluation of the effect of three dimensional (3D) coronary plaque characteristics derived from two dimensional (2D) invasive angiography images (ICA) on coronary flow determined by TIMI frame count (TFC) in acute coronary syndrome (ACS) has not been thoroughly investigated. A total of 71 patients with STEMI, and 73 with NSTEMI were enrolled after primary angioplasty. Pre- and post-PCI TFCs were obtained. From 2D images, 3D reconstruction was performed of the culprit vessel, and multiple plaque parameters were measured. In STEMI, the average post-PCI frame count decreased significantly, resulting in better flow. With regards to 2/3D parameters, no differences were found between the STEMI and NSTEMI groups. The 3D parameters in the subgroup with an increase with at least three frames resulting in worsening post-PCI flow were compared to parameters of the patients with improved or significantly not change flow (delta frame count < 3), and greater minimal luminal diameter and area was found in the worsening (increased) frame group. In STEMI 2/3D, parameters showed no correlation with worsening flow, whereas in NSTEMI, greater minimal luminal diameter and area correlated with decreased flow. We can conclude that certain 2/3D parameters can predict slower flow in ACS, resulting in the use of GP IIb/IIIa receptor blocker.

Management of failed thrombolysis after acute myocardial infarction: An overview of current treatment options

Thrombolytic therapy remains the most commonly administered revascularization strategy for patients with ST-elevation myocardial infarctions (STEMI). However, many patients fail to have patent arteries or ST-segment resolution after these therapies. Multiple strategies have been examined to treat these patients with "failed thrombolysis." We examined the existing medical literature regarding treatment of failed thrombolysis including strategies testing repeat thrombolytic therapy and rescue percutaneous coronary intervention. Additional, we reviewed the literature regarding the efficacy of transferring patient for rescue percutaneous intervention and coronary stenting. The impact of contemporary antiplatelet strategies, cardiogenic shock, and coronary bypass surgery was examined. Overall, the management of patients with acute STEMI in whom thrombolytic therapy failed remains a challenging problem. As a result, many different strategies are currently in use. Among these therapeutic interventions, rescue PCI with coronary stenting appears to be superior when it is done in a timely manner by an experienced center.

Current assessments of the adequacy of myocardial perfusion during acute MI

For two decades now, the optimal management of acute coronary syndrome has been the early restoration of complete and sustained flow to the jeopardized infarct area. Advances in thrombolytic therapy and percutaneous coronary interventions have contributed significantly to the re-establishment of epicardial flow. However, a body of evidence now strongly indicates that restoration of epicardial flow alone is not sufficient to optimize clinical outcomes. Rather, it has become evident that reperfusion therapy must also involve restoration of microcirculatory reperfusion. Thus, techniques to assess myocardial perfusion during acute myocardial infarction are becoming increasingly relevant for the assessment of patient prognosis.

Myocardial Reperfusion: Its Assessment and Its Relation to Clinical Outcomes

It has become increasingly apparent that epicardial blood flow restoration is necessary, but not sufficient, to achieve optimal clinical outcomes in the setting of acute coronary syndromes. Indeed, clinical outcomes are strongly associated with myocardial perfusion. The diagnostic tools available to assess myocardial perfusion following acute myocardial infarction and their association with clinical outcomes are reviewed here. Many simple angiographic markers--the Thrombolysis in Myocardial Infarction (TIMI) count frame, TIMI myocardial perfusion grade, pulsatile flow--are all readily available measures and are strongly related to clinical outcomes. Other tools, while accurate, remain limited by their high cost, low availability, and complexity for routine use.