Histopathology of human extremital arteries throughout life. Including measurements of cystolic pressures in ankle and arm.

Specimens from the paired radial, anterior tibial and dorsalis pedis arteries in 30 humans (age 0-82 years) were obtained at autopsy and were assessed histologically. The arterial intima was found to be significantly thickened in the lower extremity in persons older than 15 years. In both arm and leg there was significantly progressive intimal thickening with age. In persons older than 50, the arterial intimal thickening in the leg was sometimes accompanied by medial sclerosis of the Mönckeberg type, whereas the radial arteries were unaffected. The systolic blood pressure was measured simultaneously in radial and posterior tibial arteries in 25 normotensive persons (12 men, 13 women) in supine and in erect position. The ankle pressure was on average 17 mmHg higher than the arm pressure in the supine position. In standing, this difference was increased to 103 mmHg in men and 93 mmHg in women. The corresponding means of absolute systolic pressure at the ankle were, respectively, 238 and 215 mmHg. The rise in the ankle arterial pressure on standing is secondary to the pressure exerted by the hydrostatic column in the arteries between heart and feet level, and thus is dependent on total body height. The intermittent hypertension in the lower extremities in accordance with posture probably is the principal factor for the more pronounced intimal thickening in the leg arteries. This hypothesis and its implications are discussed.