title: A prominent R wave in V(1) but not in V(2) is a specific sign of a large lateral transmural infarction.
abstract: OBJECTIVE
  In the absence of right ventricular hypertrophy or bundle-branch block, a prominent R wave in V(1) or V(2) is considered to reflect a lateral myocardial infarction. We investigated the differences in infarct location, size and transmural extent between patients with prominent R wave in V(1) and those with prominent R wave in V(2).
  
  
  METHODS
  We studied 50 patients with a previous first infarction involving left ventricular inferior and/or lateral wall at contrast-enhanced magnetic resonance.
  
  
  RESULTS
  A prominent R wave in V(1) was present in 8 patients (16%), in V(2) in 23 (46%). At magnetic resonance, the infarction involved the inferior wall in 11 patients (22%), the lateral wall in 6 (12%), and both walls in 33 patients (66%). The sensitivity of a prominent R wave in V(1) in detecting a lateral infarction was low (17.9%), while the specificity was high (90.9%). The sensitivity and specificity of a prominent R wave in V(2) were 46.2% and 54.5%, respectively. In patients with a prominent R wave in V(1), infarct size and lateral and transmural extent were greater than in patients without this pattern (P<.005, <.001, and <.05, respectively); conversely, infarct size and transmural extent in the inferior wall and in its basal-posterior segment were not significantly different. In patients with a prominent R wave in V(2), infarct size, lateral and transmural extent were not different from patients without this pattern.
  
  
  CONCLUSIONS
  Only a prominent R wave in V(1) is a specific sign of large and transmural lateral infarction.
authors.affiliation: CNR, Istituto di Fisiologia Clinica, Pisa, Italia. drovai@ifc.cnr.it
authors.forename: Daniele
authors.initials: D
authors.lastname: Rovai
authors.forename: Gianluca
authors.initials: G
authors.lastname: Di Bella
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Rossi
authors.forename: Alessandro
authors.initials: A
authors.lastname: Pingitore
authors.forename: Antonio
authors.initials: A
authors.lastname: L'abbate
mesh_terms: D000368:Aged; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000473:pathology; D016277:Ventricular Function, Left / Q000502:physiology