BACKGROUND: Local Pulse Pressure (PP) is an independent determinant of carotid artery wall thickness, stronger than mean BP. The present study was designed to assess whether a beta-adrenoceptor antagonist or an ACE inhibitor-based treatment was able to reduce carotid artery wall hypertrophy through the reduction in carotid PP rather than by lowering mean BP, and whether the influence of local PP reduction could also be detected at the site of a muscular artery, the radial artery. METHODS AND RESULTS: Ninety-eight essential hypertensive patients were randomised to 9 months of double-blind treatment with either celiprolol or enalapril. Arterial parameters were determined with high resolution echotracking systems. PP was measured locally with PP applanation tonometry, and independently of mean BP. After 9 month's treatment, mean BP, carotid PP and intima-media thickness (IMT) decreased significantly, with no difference between the tow groups. The reduction in carotid pression pulsee, but not in mean BP, was a major independent determinant of the reduction in carotid IMT. Radial artery IMT and PP decreased significantly with both treatments. However, the reduction in radial artery IMT was not related to the changes in radial artery PP. CONCLUSION: The regression of carotid artery wall hypertrophy during long-term antihypertensive treatment was dependent on the reduction in local PP rather than on the lowering of mean BP. The effect of PP lowering on IMT reduction was observed at the site of an elastic artery but not at the site of a muscular artery.