The association between exercise blood pressure and the prevalence of ECG abnormalities.

The relationship between atrial and ventricular electrocardiographic abnormalities and exercise systolic blood pressure was studied in 246 male and 183 female subjects, of whom 199 males and 158 females were normotensive (resting blood pressure below 140/90 mmHg) and 47 males and 25 females were borderline hypertensive (resting systolic blood pressure 140 to 159 and/or diastolic blood pressure 90 to 99 mmHg). Subjects were classified into three groups according to systolic blood pressure during treadmill exercise (less than or equal to 180 mmHg, 180 to 199 mmHg and greater than or equal to 200 mmHg). With respect to atrial electrocardiographic abnormalities, the prevalence of abnormal values of the P-terminal force in lead V1 increased significantly with increased levels of resting exercise systolic blood pressure in males and females. The prevalence of electrocardiographic left ventricular hypertrophy, as reflected in abnormal values of one or more RS voltage indices, increased significantly with exercise systolic blood pressure in males but not in females. Males did not show a trend of increasing electrocardiographic left ventricular hypertrophy with increased resting systolic blood pressure means. In females, the significant difference between resting systolic blood pressure means and electrocardiographic left ventricular hypertrophy did not reflect a linear progression across resting systolic blood pressure categories. The significant association of the P-terminal force in lead V1 with exercise systolic blood pressure has not previously been reported. Although an association between left ventricular hypertrophy and exercise systolic blood pressure in hypertensives has been reported by others, the association seen in normotensive and borderline hypertensive males has not been reported previously.(ABSTRACT TRUNCATED AT 250 WORDS)