title: Novel methodology for the detection of exercise-induced myocardial wall motion abnormalities by surface electrocardiogram during exercise test.
abstract: BACKGROUND
  We investigated whether ischemia-induced wall motion abnormalities during exercise test modify electrical vector variation.
  
  
  METHODS
  We performed treadmill exercise test and thallium 201 scintigraphy in 150 normotensives. Beat-to-beat change of direction of S wave in V(1) (reference lead) was compared with that of R wave in V(5) and aVF, representative of anterior and inferior walls, respectively. The percentage of neighboring QRS couples where S wave in V(1) and R wave in V(5) or aVF change toward the same direction (increase or decrease) constitutes V1-V5 and V1-aVF indexes.
  
  
  RESULTS
  V1-V5 and V1-aVF indexes were significantly decreased in subjects with reversible anterior or inferior ischemia, respectively. A decrease in V1-V5 index ≥0.14 defines those with anterior wall ischemia (sensitivity, 100%; specificity, 75.5%), whereas a decrease in V1-aVF index ≥0.05 defines those with inferior wall ischemia (sensitivity, 92.3%; specificity, 61.5%).
  
  
  CONCLUSIONS
  These novel electrocardiographic exercise test indexes improved significantly their sensitivities.
authors.affiliation: 1st Department of Cardiology, Medical School of Athens University, Hippokration Hospital, Athens, Greece.
authors.forename: Andreas P
authors.initials: AP
authors.lastname: Michaelides
authors.forename: Spyros
authors.initials: S
authors.lastname: Massias
authors.forename: Charalambos
authors.initials: C
authors.lastname: Antoniades
authors.forename: Dimitris
authors.initials: D
authors.lastname: Tsiachris
authors.forename: Polychronis
authors.initials: P
authors.lastname: Dilaveris
authors.forename: Athanasios
authors.initials: A
authors.lastname: Aggelis
authors.forename: Charalampos
authors.initials: C
authors.lastname: Liakos
authors.forename: Kyriakoula
authors.initials: K
authors.lastname: Marinou
authors.forename: Leonidas
authors.initials: L
authors.lastname: Raftopoulos
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Soulis
authors.forename: Christodoulos
authors.initials: C
authors.lastname: Stefanadis
mesh_terms: D016009:Chi-Square Distribution; D004562:Electrocardiography / Q000379:methods*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D012372:ROC Curve; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D013794:Thallium Radioisotopes