This is a newly updated second edition of Blood Pressure Monitoring in Cardiovascular Medicine and Therapeutics. William B. White, MD, and a panel of highly experienced clinicians critically review every aspect of out-of-office evaluation of blood pressure. The world-class opinion leaders writing here describe the significant advances in our understanding of the circadian pathophysiology of cardiovascular disorders.
Although the monitoring of antihypertensive treatment is usually
performed using blood pressure readings made in the physician’s office
and having a blood pressure check is by far the most common reason
for visiting a physician, it is neither a reliable nor an efficient process.
Thus, physician’s measurements are often inaccurate as a result of poor
technique, often unrepresentative because of the white coat effect, and
rarely include more than three readings made at any one visit. It is often
not appreciated how big variations in blood pressure can be when
measured in the clinic. In a study conducted by Armitage and Rose
in 10 normotensive subjects, two readings were taken on 20 occasions
over a 6-wk period by a single trained observer (1). The authors concluded
that “the clinician should recognize that the patient whose
diastolic pressure has fallen 25 mm from the last occasion has not necessarily
changed in health at all; or, if he is receiving hypotensive therapy,
that there has not necessarily been any response to treatment.” In
addition, blood pressure can decrease by 10 mmHg or more within the
time of a single visit if the patient rests, as shown by Alam and Smirk
in 1943 (2). There is also a practical limitation to the number or frequency
of clinic visits that can be made by the patient, who may have
to take time off work to make the visit.