IMPACT OF METABOLIC RISK FACTORS ON ASCENDING AORTIC PRESSURE RESPONSE DURING AND AFTER DYNAMIC EXERCISE IN HYPERTENSIVE SUBJECTS: PP.14.45

Abstract

Objective: This study aimed to evaluate the ascending aortic pressure response to dynamic exercise with risks of cardiovascular diseases associated with hypertension. Design and Method: Thirty-four male volunteers (aged 51±7 years; mean±s.d.) who were free from cerebrovascular and cardiovascular diseases, diabetes mellitus and renal diseases were examined. The subjects exercised for 10 min on a bicycle ergometer at 50 rpm and at a heart rate equal to 50% of their heart rate reserve. At baseline, during and after the cycle exercise, peripheral pulse waveforms were recorded by a radial applanation tonometry. Ascending aortic pressure waveforms were then estimated using a generalized transfer function. Pulse pressure amplification, defined as the ratio of peripheral to central pulse pressure, was used as a marker of wave reflection. Results: Compared to the baseline, pulse pressure amplification significantly increased during exercise, and after the exercise it gradually decreased to the baseline level. We divided the subjects into subgroups according to the presence or absence of hypertension, dyslipidemia and glucose intolerance. Throughout the exercise test, pulse pressure amplifications in the subjects with hypertension were significantly lower than those with normal blood pressure. Furthermore, those with clustering the metabolic risk variables, including hypertension together with at least one of dyslipidemia and glucose intolerance, had significantly reduced pulse pressure amplification after exercise compared to those with hypertension alone. In multiple regression analysis, the post-exercise pulse pressure amplification was independently associated with the age and the presence of multiple risk variables including hypertension. There was a significant negative correlation between post-exercise pulse pressure amplification and left ventricular mass index. Conclusions: These results suggest that pulse pressure amplification is associated with the hypertension, dyslipidemia and glucose intolerance, and with increased left ventricular mass. Thus, the measurement of ascending aortic pressure during and after exercise may be useful in investigating the hypertension-related risks of cardiovascular diseases.