title: The orthogonal electrocardiogram in adult Nigerians: a preliminary report.
abstract: The Orthogonal ECG (Frank Lead System) was analysed in 664 asymptomatic normal Nigerians (333 Males: 331 Females) aged 15 to 90 years (mean: 39.1 +/- 16.7). The system gave the same information as the 12-Lead EGG concerning the heart rate and rhythm, durations of waves, intervals and segments, J-point elevation and ST-T variants. QRS morphology was of the left ventricular pattern with the Rs greater than R greater than qRS greater than qR patterns dominating the scene in X and Y leads, and QR much greater than qR in 2. All these suggest that the cardiac vector is oriented leftwards, inferiorly and posteriorly. There was no QS pattern in any lead. There was no Sx dominance, and no S wave in Z. Septal Q, recorded in 29.2% of X and 25.1% of Y did not exceed 0.3 seconds and 2 mm. There was no Tx or Ty inversion. Rather, they were upright (98.3% and 95.9% respectively) and rarely flat (1.7%:4.1%). The Orthogonal ECG is recommended as a simple, accurate system for clinical use either as a supplement to or in lieu of the 12-lead system.
authors.affiliation: Department of Medicine, University of Ilorin, Nigeria.
authors.forename: M A
authors.initials: MA
authors.lastname: Araoye
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004562:Electrocardiography / Q000295:instrumentation / Q000379:methods / Q000592:standards*; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009549:Nigeria; D012016:Reference Values; D015203:Reproducibility of Results