2. Normal-adaptability: normal blood pressure and no symptoms of hypotension, no neurally mediated syncope or vasovagal syncope (spontaneous or induced in the tilt table test) and no presence of hypotension. Include those who develop permanent hypertension after 65 yo. After this age, structural components mainly in the Windkessel vessels, may contribute more than the increased sympathetic tone to the hypertension phenomenon. For end points analysis, patients developing Hypertension after 65 yo are considered hypertensives in their BP group, but normal in the adaptability.