Elevated blood pressure and electrocardiographic frontal T axis and spatial QRS-T angle changes in postmenopausal women.
BACKGROUND
Frontal T axis and spatial QRS-T angle are both measures of disturbances in ventricular repolarization and depolarization. We determined whether increased blood pressure is a risk factor for changes in these parameters in postmenopausal women free of left ventricular hypertrophy.


METHODS
This cross-sectional study included 969 women. A standard 12-lead electrocardiogram (ECG) was recorded, and frontal T axes and spatial QRS-T angles were computed from vectorcardiography. Logistic regression analysis was used to assess the relationship between systolic and diastolic blood pressures on the one hand and both ECG parameters on the other.


RESULTS
Odds ratios were 1.08 (95% confidence interval [CI], 0.99-1.18) and 1.12 (95% CI, 1.03-1.23) per 10 mm Hg systolic blood pressure for frontal T axis and QRS-T angle, respectively. These values were 1.05 (95% CI, 0.95-1.16) and 1.12 (95% CI, 1.02-1.23) per 5 mm Hg diastolic blood pressure for frontal T-axis and QRS-T angle, respectively.


CONCLUSIONS
Elevated blood pressure may lead to ventricular depolarization and repolarization disturbances before overt ECG left ventricular hypertrophy has developed.
Atsma
Femke
F
Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands.
Bartelink
Marie-Louise E L
ML
van der Schouw
Yvonne T
YT
Kors
Jan A
JA
Grobbee
Diederick E
DE
D000368:Aged; D015331:Cohort Studies; D015897:Comorbidity; D003430:Cross-Sectional Studies; D004562:Electrocardiography / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000453:epidemiology*; D015994:Incidence; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D017698:Postmenopause; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D018487:Ventricular Dysfunction, Left / Q000453:epidemiology*