Coronary no‐reflow phenomenon: From the experimental laboratory to the cardiac catheterization laboratory

Abstract

Coronary no-reflow occurs commonly during acute percutaneous coronary intervention, particularly in patients with acute myocardial infarction and those with degenerated vein grafts. It is associated with a guarded prognosis, and thus needs to be recognized and treated promptly. The pathophysiology originates during the ischemic phase and is characterized by localized and diffuse capillary swelling and arteriolar endothelial dysfunction. In addition, leukocytes become activated and are attracted to the lumen of the capillaries, exhibit diapedesis and may contribute to cellular and intracellular edema and clogging of vessels. At the moment of perfusion, the sudden rush of leukocytes and distal atheroemboli further contributes to impaired tissue perfusion. Shortening the door-to-balloon time, use of glycoprotein IIb/IIIa platelet receptor inhibitors and distal protection devices are predicted to limit the development of no-reflow during percutaneous interventions. Distal intracoronary injection of verapamil, nicardipine, adenosine, and nitroprusside may improve coronary flow in the majority of patients. Hemodynamic support of the patient may be needed in some cases until coronary flow improves.

Coronary thrombus in patients undergoing primary PCI for STEMI: Prognostic significance and management

“…However, a substantial number of STEMI patients, up to 40%, treated with PPCI shows poor procedural outcomes [25] , above all because of the presence of intracoronary thrombi that can lead to micro and macro distal embolization, thus reducing the benefits of PCI [25] . Actually, although PPCI effectively restores flow in the IRA, myocardial perfusion often remains suboptimal, with persistent ST-segment elevation, abnormal myocardial blush grade and abnormal TIMI frame count, due to microvascular obstruction, mostly attributed to distal embolization [45] . As a result, management of lesions with a consistent thrombotic burden is still challenging during PPCI for STEMI.…”

“The Sticky LAD”: Large Intracoronary Thrombus in an Aneurysmal Left Anterior Descending Artery Presenting as ST-Elevation Myocardial Infarction

“…Subgroups may benefit more from adjunctive pharmacological and interventional strategies, such as large thrombus burden. In our case, aside from PCI with stenting of the involved segment, thrombectomy may be of benefit for angiographic success [3,4], which was done. The combination of STEMI with ectatic (aneurysmal) coronaries and a large intracoronary thrombus burden is uncommon and its management varies from a few published case reports.…”

Relationship between TIMI frame count and admission glucose values in acute ST elevation myocardial infarction patients who underwent successful primary percutaneous intervention

“…Therefore, in addition to no-refl ow phenomenon, high blood glucose values might also cause subtle changes in coronary fl ow despite the presence of fi nal TIMI 3 fl ow of the culprit coronary artery. Plugging of leucocytes in the microcirculation might contribute to the impaired coronary fl ow (22). Also, blood glucose is an independent predictor of platelet dependent thrombosis.…”