title: Screening entire healthcare system ECG database: Association of deep terminal negativity of P wave in lead V1 and ECG referral with mortality.
abstract: BACKGROUND
  Each encounter of asymptomatic individuals with the healthcare system presents an opportunity for improvement of cardiovascular disease (CVD) awareness and sudden cardiac death (SCD) risk assessment. ECG sign deep terminal negativity of the P wave in V1 (DTNPV1) was shown to be associated with an increased risk of SCD in the general population.
  
  
  OBJECTIVE
  To evaluate association of DTNPV1with all-cause mortality and newly diagnosed atrial fibrillation (AFib) in the large tertiary healthcare system patient population.
  
  
  METHODS
  Retrospective double cohort study compared two levels of exposure (automatically measured amplitude of P-prime (Pp) in V1): DTNPV1(Pp from -100μV to -200μV) and ZeroPpV1 (Pp=0). An entire healthcare system (2010-2014) ECG database was screened. Medical records of children and patients with previously diagnosed AFib/atrial flutter (AFl), implanted pacemaker or cardioverter-defibrillator were excluded. DTNPV1(n=3,413) and ZeroPpV1 (n=3,405) cohorts were matched by age and sex. Primary outcome was all-cause mortality. Secondary outcomes were newly diagnosed AFib/AFl. Median follow-up was 2.5 y.
  
  
  RESULTS
  DTNPV1was associated with all-cause mortality (HR 1.95(1.64-2.31); P<0.0001) and newly diagnosed AFib (HR 1.29(1.04-1.59); P=0.021) after adjustment for CVD, comorbidities, other ECG parameters, medications, and index ECG referral. Index ECG referral by a cardiologist was independently associated with 34% relative risk reduction of mortality (HR 0.66(0.52-0.84); P=0.001), as compared to ECG referral by a non-cardiologist.
  
  
  CONCLUSIONS
  DTNPV1is independently associated with twice higher risk of all-cause death, as compared to patients without P prime in V1. Life-saving effect of the index ECG referral by a cardiologist requires further study.
authors.affiliation: Oregon Health and Science University, School of Medicine, Portland, OR, United States.
authors.forename: Allison
authors.initials: A
authors.lastname: Junell
authors.affiliation: Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, United States.
authors.forename: Jason
authors.initials: J
authors.lastname: Thomas
authors.affiliation: Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, United States; Emory University, Atlanta, GA, United States.
authors.forename: Lauren
authors.initials: L
authors.lastname: Hawkins
authors.affiliation: Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, United States.
authors.forename: Jiri
authors.initials: J
authors.lastname: Sklenar
authors.affiliation: Oregon Health and Science University, School of Medicine, Portland, OR, United States; Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, United States.
authors.forename: Trevor
authors.initials: T
authors.lastname: Feldman
authors.affiliation: Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, United States.
authors.forename: Charles A
authors.initials: CA
authors.lastname: Henrikson
authors.affiliation: Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, United States. Electronic address: tereshch@ohsu.edu.
authors.forename: Larisa G
authors.initials: LG
authors.lastname: Tereshchenko
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000401:mortality*; D001282:Atrial Flutter / Q000175:diagnosis* / Q000401:mortality*; D016208:Databases, Factual; D016757:Death, Sudden, Cardiac / Q000453:epidemiology*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012017:Referral and Consultation; D012189:Retrospective Studies
keywords: Electrocardiogram; Health system; Mortality; Patient education