title: Preinfarction angina: clinical significance and relationship with total ischemic time in patients with ST-elevation myocardial infarction.
abstract: OBJECTIVE
  Preinfarction angina (PIA) may play a protective role in patients with ST-elevation myocardial infarction. Data on the relationship between PIA and time to reperfusion are scarce. We aimed to assess infarct size by peak troponin-T (TnT) in patients with or without PIA in three different time intervals to a primary percutaneous coronary intervention (PPCI), the relationship between PIA and left ventricular ejection fraction, and its impact on midterm survival.
  
  
  METHODS
  Single-center, retrospective analyses were carried out of 575 consecutive PPCI-treated patients, divided into three groups from symptom onset to reperfusion: less than 3, 3-6, and greater than 6 h.
  
  
  RESULTS
  Patients with PIA had smaller infarct size [TnT=3.76 (5.07) vs. 5 (6.12) ng/ml, P=0.024]. Infarct size of patients with PIA versus no-PIA was lower for patients presenting within 3-6 h from onset of symptoms [3.73 (5.38) vs. 5.53 (6.9) ng/ml, P=0.028], but not different for those who presented less than 3 h [4.15 (5.53) vs. 4.0 (3.96) ng/ml, P=0.702] nor for those who presented greater than 6 h [3.65 (4.24) vs. 5.0 (5.9) ng/ml, P=0.141]. On multivariate analyses, only PIA protected from moderate to severe left ventricle dysfunction (odds ratio=0.557, 95% confidence interval: 0.352-0.881, P=0.012), but failed to reduce overall mortality [hazard ratio=0.784, 95% confidence interval: 0.356-1.724, P=0.545; median follow-up time=23 (20) months].
  
  
  CONCLUSIONS
  PPCI-treated patients within 3-6 h from symptom onset had smaller infarcts if they had experienced PIA, with no benefit for those who presented less than 3 h nor for those who presented greater than 6 h from symptom onset. Moderate to severe left ventricle dysfunction was less prevalent in PIA patients. However, PIA failed to have an independent impact on midterm survival.
authors.affiliation: aDepartment of Cardiology, Porto Hospital Center bInstitute of Biomedical Sciences of 'Abel Salazar' cDepartment of Physiology and Cardiothoracic Surgery, Faculty of Medicine, University of Porto, Porto, Portugal.
authors.forename: André
authors.initials: A
authors.lastname: Luz
authors.forename: Mário
authors.initials: M
authors.lastname: Santos
authors.forename: Patrícia
authors.initials: P
authors.lastname: Rodrigues
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Sousa
authors.forename: Diana
authors.initials: D
authors.lastname: Anjo
authors.forename: Inês
authors.initials: I
authors.lastname: Silveira
authors.forename: Bruno
authors.initials: B
authors.lastname: Brochado
authors.forename: João
authors.initials: J
authors.lastname: Silveira
authors.forename: Sofia
authors.initials: S
authors.lastname: Cabral
authors.forename: Adelino
authors.initials: A
authors.lastname: Leite-Moreira
authors.forename: Henrique
authors.initials: H
authors.lastname: Carvalho
authors.forename: Severo
authors.initials: S
authors.lastname: Torres
mesh_terms: D000368:Aged; D000787:Angina Pectoris / Q000097:blood / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D015415:Biomarkers / Q000097:blood; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D016017:Odds Ratio; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects / Q000401:mortality; D011174:Portugal; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013318:Stroke Volume; D013997:Time Factors; D061665:Time-to-Treatment; D016896:Treatment Outcome; D020107:Troponin T / Q000097:blood; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D016277:Ventricular Function, Left
chemical_list: D015415:Biomarkers; D020107:Troponin T