Abstract 5529: Excessive Inotropic Response During Exercise Reflects Cardiovascular Stiffening in Newly Diagnosed Essential Hypertensives
Introduction: Exaggerated blood pressure response during exercise (EBPR) is associated with high risk for worsening hypertension, while arterial stiffness and left ventricular (LV) diastolic dysfunction have both been related with adverse cardiovascular outcomes.
Hypothesis: EBPR may be associated with arterial stiffness and LV diastolic dysfunction in a large cohort of hypertensives.
Methods: 222 untreated non-diabetics (152 males, mean age 54 years) with stage I – II EH underwent treadmill exercise testing and were classified as hypertensives with EBPR (n=75) based on the systolic BP elevation ≥210mmHg for men and ≥190mmHg for women, at peak exercise. The remaining patients were classified as normal inotropic responders (n=147). In all subjects carotid to femoral pulse wave velocity (PWV) was measured by means of Complior SP, while LV diastolic function was estimated by pulsed Tissue Doppler Imaging (TDI), averaging diastolic mitral annular velocities (Em, Am) from 4 separate sites of measurement.
Results: Hypertensives with EBPR compared to normal inotropic responders had increased 24-hour systolic BP (137.4±10 vs 134±9mmHg, p=0.013) and PP (52.6±8 vs 49±7mmHg, p=0.001), while there was no difference in terms of age, sex and body mass index. Hypertensives with EBPR exhibited also greater relative wall thickness (0.47±0.06 vs 0.44±0.07, p=0.014), E/Em (9.45±3.1 vs 8.35±3.3, p=0.034) and PWV (9.1±1.6 vs 8.5±1.3m/s, p=0.007), as well as significantly lower values of Em (8.5±2.5 vs 9.4±2.9cm/s, p=0.046), while they did not differ in LV mass index and transmitral flow Doppler parameters (p=NS for all). Exercise capacity was also significantly deteriorated in hypertensives with EBPR based on the lower values of achieved METs (9.95±2.3 vs 11±2.3, p=0.003). Peak systolic BP at exercise was correlated with 24-hour systolic BP (r=0.240, p<0.001), 24-hour PP (r=0.218, p=0.001), PWV (r=0.152, p=0.046) and E/Em (r=0.150, p=0.049). Multiple logistic regression analysis revealed that PWV was the only independent predictor of EBPR (OR=1.31, p=0.047).
Conclusions: EBPR constitutes a sign of cardiovascular stiffening in the setting of newly diagnosed EH, further elucidating the adverse prognostic role of abnormal systolic BP elevation at peak exercise.