Advantages and disadvantages of non-invasive ambulatory blood pressure monitoring.

Our studies have shown that (1) automatic blood pressure readings obtained from portable monitors do not induce any alerting reaction or pressor response in the patient; (2) although the measurements are intermittent, non-invasive ambulatory blood pressure monitoring is able to provide a true estimate of 24-h blood pressure and heart rate mean values (the assessment of 24-h blood pressure and heart rate variabilities is less accurate); (3) the nocturnal fall in blood pressure is not altered by the possible disturbance to the patient's sleep induced by repeated cuff inflations; and (4) even when the automatic blood pressure readings obtained are similar to simultaneous readings obtained by a sphygmomanometer, the accuracy of the values provided by portable monitors used in truly ambulatory conditions cannot be taken for granted. These findings have particular implications for the cost: benefit ratio if ambulatory blood pressure monitoring is to be used in the routine evaluation of hypertensive patients.