Effect of Prodromal Angina Pectoris on the Infarct Progression in Patients With First ST-Elevation Acute Myocardial Infarction

Abstract

Circulation Journal Official Journal of the Japanese Circulation Society http://www. j-circ.or.jp he time elapsed from coronary occlusion to reperfusion is 1 of the most important factors that determine the extent of myocardial necrosis. 1,2 After coronary occlusion, myocardial necrosis first occurs in the subendocardial region but with increasing duration of the occlusion, irreversible injury progresses as a wavefront toward the subepicardium. 3,4 This infarct progression is modified by several factors, including the presence of functioning collateral coronary arteries to the area at risk, myocardial oxygen demands, and ischemic preconditioning. Episodes of transient ischemia protect the myocardium against subsequent prolonged ischemia. Prodromal angina pectoris (AP) has a cardioprotective effect by the mechanism of ischemic preconditioning. 5 Experimental studies have demonstrated that ischemic preconditioning delays the progression of myocardial infarction (MI). 6,7However, there are no clinical data on the effect of prodromal AP on progression of MI in humans, because of the difficulty in measuring the extent of myocardial necrosis before reperfusion. Development of Q wave and R-wave regression of the electrocardiogram (ECG) reflects the progression of the infarction process, and the QRS score has been used to estimate the size of myocardial necrosis. 8-12 QRS score at presentation is a measure of myocardial necrosis before reperfusion and predict myocardial salvage and major adverse cardiac events. 13,14 This study was undertaken to investigate the effect of prodromal AP on the relationship between time to reperfusion and myocardial necrosis assessed by QRS score before reperfusion in patients with ST-elevation acute MI (AMI). Background: Prodromal angina pectoris (AP) has a cardioprotective effect by the mechanism of ischemic preconditioning, and the QRS score on the admission electrocardiogram (ECG) reflects myocardial damage at presentation. This study was undertaken to investigate the effect of prodromal AP on infarct progression after the onset of acute myocardial infarction (AMI).

Effects of Remote Ischemic Preconditioning With Postconditioning in Patients Undergoing Off-Pump Coronary Artery Bypass Surgery

“…27, 28 For example, antecedent angina may have had a preconditioning effect on some patients. 29, 30 Furthermore, we cannot rule out the possibility that the control group was also preconditioned by such factors. Unfortunately, subgroup analysis could not be conducted to identify these factors due to the relatively small number of patients.…”

Acute Hyperglycemia in Patients With Acute Myocardial Infarction

“…30 Ischemic preconditioning delays infarct progression during the early hours after the onset of AMI and extends the window of time for reperfusion therapy. 31 More importantly, ischemic preconditioning decreases the extent of reperfusion injury. 32, 33 The molecular mechanism of ischemic preconditioning is complex, but the mitochondrial KATP channels in myocytes play a key role.…”

Prognostic value of the combination of GRACE risk score and mean platelet volume to lymphocyte count ratio in patients with ST‑segment elevation myocardial infarction after percutaneous coronary intervention

“…Out of 556 patients initially enrolled, 464 patients met the inclusion criteria, and all provided written informed consent. 'Prodromal angina' (PA) was defined as a chest pain episode typically limited to 24 h before infarction (22). No-reflow was defined as the absence of effective perfusion of myocardial tissue (TIMI flow-grade lower than 3) after coronary artery recanalization without obvious spasm, dissection and residual stenosis (23).…”