| Popis: |
The relationship between atrial and ventricular echocardiographic abnormalities and ergometric exercise systolic blood pressure was studied in 77 apparently healthy men, of whom the majority (77%) were normotensive (resting blood pressure less than 140/90 mmHg), and the remainder (23%) borderline hypertensive (resting systolic blood pressure 140 to 159 mmHg and/or diastolic blood pressure 90 to 95 mmHg). Four categories of exercise systolic blood pressure were defined (less than 190, 190 to 199, 200 to 209 and greater than or equal to 210 mmHg). Left ventricular mass and left atrial dimension were measured by M-mode echocardiography and divided by body surface area to derive the left ventricular mass index and the left atrial dimension index. The prevalence of left ventricular hypertrophy, defined as a left ventricular mass index greater than or equal to 125 g/m2, was 11%. Two key findings were the much higher prevalence of left atrial enlargement, defined as left atrial dimension index greater than or equal to 2 cm/m2 at 23%, and the fact that left atrial enlargement occurred in the absence of left ventricular hypertrophy in the majority of subjects, whereas occurrence of left ventricular hypertrophy in the absence of left atrial enlargement was rare. This is consistent with the view that left atrial enlargement is a common precursor of left ventricular hypertrophy. Multivariate analysis showed exercise systolic blood pressure and cardiac index to be independent predictors of left atrial dimension index and left ventricular mass index (R2 for statistical models was 0.38 [P less than 0.0001] and 0.47 [P less than 0.0001], respectively).(ABSTRACT TRUNCATED AT 250 WORDS) |
