title: Time of symptom onset and value of myocardial blush and infarct size on prognosis in patients with ST-elevation myocardial infarction.
abstract: In patients with ST-segment elevation myocardial infarction (STEMI), the time of onset of ischemia has been associated with myocardial infarction (MI) size. Myocardial blush grade (MBG) reflects myocardial response to ischemia/reperfusion injury, which may differ according to time of the day. The aim of our study was to explore the 24-hour variation in MBG and MI size in relation to outcomes in STEMI patients. A retrospective multicenter analysis of 6970 STEMI patients was performed. Time of onset of STEMI was divided into four 6-hour periods. STEMI patients have a significant 24-hour pattern in onset of symptoms, with peak onset around 09:00 hour. Ischemic time was longest and MI size, estimated by peak creatine kinase concentration, was largest in patients with STEMI onset between 00:00 and 06:00 hours. Both MBG and MI size were independently associated with mortality. Time of onset of STEMI was not independently associated with mortality when corrected for baseline and procedural factors. Interestingly, patients presenting with low MBG between 00:00 and 06:00 hours had a better prognosis compared to other groups. In conclusion, patients with symptom onset between 00:00 and 06:00 hours have longer ischemic time and consequently larger MI size. However, this does not translate into a higher mortality in this group. In addition, patients with failed reperfusion presenting in the early morning hours have better prognosis, suggesting a 24-hour pattern in myocardial protection.
authors.affiliation: Thoraxcenter, Department of Cardiology, University of Groningen, University Medical Center Groningen , Groningen , The Netherlands .
authors.forename: Wouter G
authors.initials: WG
authors.lastname: Wieringa
authors.forename: Chris P H
authors.initials: CP
authors.lastname: Lexis
authors.forename: Karim D
authors.initials: KD
authors.lastname: Mahmoud
authors.forename: Jan Paul
authors.initials: JP
authors.lastname: Ottervanger
authors.forename: Johannes G M
authors.initials: JG
authors.lastname: Burgerhof
authors.forename: Gabija
authors.initials: G
authors.lastname: Pundziute
authors.forename: Arnoud W J
authors.initials: AW
authors.lastname: van 't Hof
authors.forename: Wiek H
authors.initials: WH
authors.lastname: van Gilst
authors.forename: Erik
authors.initials: E
authors.lastname: Lipsic
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D002940:Circadian Rhythm; D017023:Coronary Angiography; D003326:Coronary Circulation; D003402:Creatine Kinase / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology / Q000503:physiopathology / Q000628:therapy; D009206:Myocardium / Q000201:enzymology / Q000473:pathology*; D009426:Netherlands; D062645:Percutaneous Coronary Intervention; D011379:Prognosis; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D061665:Time-to-Treatment
chemical_list: D015415:Biomarkers; D003402:Creatine Kinase
keywords: 24-hour variation; infarct size; myocardial infarction; myocardial perfusion; outcome