title: Left bundle-branch block in patients with acute myocardial infarction: Presentation, treatment, and trends in outcome from 1997 to 2016 in routine clinical practice.
abstract: Whether patients with acute myocardial infarction presenting with new or presumed new left bundle-branch block (LBBB) should be treated in the same way as those presenting with ST-elevation (STE) is still a matter of debate.
  
  
  
  Data from 28,358 patients enrolled in AMIS Plus from 1997 to 2016 were analyzed to evaluate differences in treatment and outcome of patients presenting with LBBB (n=2295) or STE (n=26,090) on their initial electrocardiogram using descriptive statistics and multivariate logistic regression.
  
  
  
  LBBB patients were older (75.0 vs 64.3 years, P<.001) with a greater burden of risk factors and comorbidities. They were admitted 80 minutes later and more frequently in Killip III/IV (20% vs 7%, P<.001). Even after adjustment for age and gender, LBBB patients were less likely to receive aspirin (odds ratio [OR] 0.40, 95% CI 0.34-0.47), P2Y12 inhibitors (OR 0.50, 95% CI 0.45-0.54), β-blockers (OR 0.81, 95% CI 0.76-0.89), and statins (OR 0.70, 95% CI 0.63-0.76) or undergo percutaneous coronary interventions (OR 0.38, 95% CI 0.35-0.42). Crude in-hospital mortality of patients with LBBB was 16.2% versus 6.5% for patients with STE, but adjusted OR was 1.07 (95% CI 0.93-1.24). Mortality of LBBB patients decreased from 22.6% in 1997-2001 to 11.9% in 2012-2016.
  
  
  
  Acute myocardial infarction patients with new or presumed new LBBB presence are at high risk of morbidity and mortality. They were treated less aggressively, and although mortality has halved during the last 20 years, there may be room for further improvement. Additional studies are needed to better identify those patients with LBBB who may maximally benefit from an early invasive treatment strategy.
authors.affiliation: AMIS Plus Switzerland, Department of Biomedicine, University of Basel, Basel, Switzerland.
authors.forename: Paul
authors.initials: P
authors.lastname: Erne
authors.affiliation: Cardiology Department, University Hospital, Lausanne, Switzerland.
authors.forename: Juan F
authors.initials: JF
authors.lastname: Iglesias
authors.affiliation: Cardiology Department, La Tour Hospital, Geneva, Switzerland.
authors.forename: Philip
authors.initials: P
authors.lastname: Urban
authors.affiliation: Department of Cardiology, Stadtspital Triemli, Zurich, Switzerland.
authors.forename: Franz R
authors.initials: FR
authors.lastname: Eberli
authors.affiliation: Department of Cardiology, Kantonsspital St. Gallen, St. Gallen, Switzerland.
authors.forename: Hans
authors.initials: H
authors.lastname: Rickli
authors.affiliation: Department of Internal Medicine, Kantonsspital Uri, Altdorf, Switzerland.
authors.forename: René
authors.initials: R
authors.lastname: Simon
authors.affiliation: Department of Cardiology, Kantonsspital Winterthur, Winterthur, Switzerland.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Fischer
authors.affiliation: AMIS Plus Data Center, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland. Electronic address: dragana.radovanovic@uzh.ch.
authors.forename: Dragana
authors.initials: D
authors.lastname: Radovanovic
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001241:Aspirin / Q000627:therapeutic use; D002037:Bundle-Branch Block / Q000150:complications / Q000628:therapy*; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000150:complications / Q000628:therapy*; D016017:Odds Ratio; D062645:Percutaneous Coronary Intervention / Q000706:statistics & numerical data*; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D010818:Practice Patterns, Physicians'; D011446:Prospective Studies; D058921:Purinergic P2Y Receptor Antagonists / Q000627:therapeutic use*; D012042:Registries; D012307:Risk Factors; D013997:Time Factors
chemical_list: D000319:Adrenergic beta-Antagonists; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D010975:Platelet Aggregation Inhibitors; D058921:Purinergic P2Y Receptor Antagonists; D001241:Aspirin