New insights in the pathophysiology of acute myocardial infarction detectable by a contemporary troponin assay

Abstract

Objectives: ST-elevation and non-ST-elevation myocardial infarction (STEMI, NSTEMI) are considered two distinct pathophysiologic entities. We evaluated cardiac troponin I (cTnI) release in STEMI and NSTEMI using a "contemporary" (CV > 10 to 20% at the 99th percentile concentration) cTnI assay for patients undergoing early percutaneous coronary intervention (PCI).Design and methods: 856 patients with suspected acute coronary syndrome consecutively admitted to the Emergency Department of the Maggiore Hospital of Novara (225 STEMI and 135 NSTEMI) were selected according to: 1) early (≤4 h from admission) and successful PCI; and 2) cTnI measurements at ED presentation and within 24 h. The influence of the MI type on cTnI concentrations at baseline and after PCI as well as the velocity of cTnI [cTnI V = absolute increase (after log conversion of cTnI measurements) / delay between the two measurements] was studied by multiple regression analysis, adjusting for patient parameters.Results: A statistically significant interaction between MI type and time from symptoms was reported on cTnI concentrations (p b 0.0001): STEMI and NSTEMI differed for cTnI releases at admission and after revascularization. Higher cTnI V in STEMI was detectable in patients admitted within 6 h from symptoms. Baseline cTnI concentrations were lower in patients with a history of coronary artery disease (CAD) and increased with aging (p b 0.0001). In the elderly (>75 years), the cTnI V was significantly increased.Conclusion: STEMI and NSTEMI patients have different patterns and dynamics of cTnI release influenced by the interaction with time from symptoms, by aging and history of CAD.

Galectin-3 in Acute Myocardial Infarction Patients with Atrial Fibrillation

“…Galectin-3 decreases immediately after necrosis, while TnI decreases over 15 days after the acute event [8]. We measured galectin-3 on the third day after admission when it was decreasing, while TnI was in the “wash-out phase” after PCI and possibly had a secondary peak [19]. Patients with higher galectin-3 levels had ticagrelor more often than clopidogrel in therapy, which could be explained by the larger atherosclerotic burden in those patients, observed in earlier studies [20].…”

ESC Working Group Cellular Biology of the Heart: Position Paper: improving the preclinical assessment of novel cardioprotective therapies

“… 72 – 74 Crucially, in patients presenting with an AMI who are treated by reperfusion therapy, the time from onset of symptoms to reperfusion can vary from 30 min to 12 h, with evidence of MI (troponin release) developing after 30 min. 40 , 75 Even then, the MI size in patients is highly variable and in theory, it can range between 5 and 40% of the LV volume depending on the site of the acute coronary occlusion. However, in clinical cardioprotection studies in which both MI size and the AAR have been measured using cardiac MRI, mean MI size as a % LV volume has been reported as 15–25%, and the mean infarct size as a % of the AAR has been found to be 39–70%.…”

The Differences in Troponin I and Ck-Mb Values in Acute Myocardial Infarction Patients With St Elevation and Without St Elevation

“…This study was conducted to determine the differences in troponin I and CK-MB values in acute myocardial infarction with ST-elevation and without ST-elevation. 12…”