ABPM - USEFUL TOOL IN
MANAGING ARTERIAL HYPERTENSION

Bernd Krönig
Dept. of Internal Medicine, Ev. Elisabeth Hospital, Theobaldstr. 12, D-54292 Trier

Ambulatory blood pressure monitoring (ABPM) is mainly applied in a non-invasive manner with intermittent blood pressure (BP) recordings every 15 min. in day-time and every 30 min. in night-time. The great number of at least 50 reliable readings per 24 hours helps to get a better insight in the BP-situation under every-day conditions, compared to casual BP´s (CS) and self measurements (SM).

ABPM has turned out to be the best method in evaluating

- diagnosis,
- treatment, and
- prognosis

of hypertensive patients. In diagnosis, patients with white coat hypertension (WCH), reverse WCH, impaired day-night-regulation, paroxysmal hypertension, and inadequate response to physical / emotional stress can be filtered out by ABPM. About 25 % of patients being hypertensives by by CS (so-called WCH) are normotensive in ABPM (=BP means in day-time < 135/85-, at night < 120/70-, and for 24 hours < 130/80 mmHg), showing only a somewhat steeper rise of the wakening BP. Vice versa, there are some patients (about 8 %) having already signs of secondary organ damage (e.g. LVH) with elevated ABPM in day-time, but still normotensive CS (so-called reverse WCH).

Regarding the day-night BP-regulation there are a great number of patients with advanced essential hypertension and probable history of stroke, myocardial infarction, resp. diabetes mellitus, who show a so-called "non-dipper"-constellation (= BP fall < 10 % / < 15 % for systolic and diastolic means during the night). Among the small population (<5%) of patients with secondary hypertension about 2/3 are "non-dippers".

Drug treatment may best be controlled by ABPM, since the individual duration of action with the aim of a 24-hour normotensive BP profile can be evaluated thoroughly. In our experience, quite a number of patients needs therefore an additional medication either at noon, at night, or even in the early morning, before getting up.

From the prognostic standpoint of view ABPM is superior to CS and SM, showing better correlations to LVH, cerebrovascular damage, and e.g. microalbuminuria. If the additional parameter "blood pressure variability", estimated by the standard deviation of interval BP means, has any progrnostic implications, is not yet settled.

In conclusion, the easily applied ABPM should be used as a routine method in every hypertensive patient, giving the most valuable results in respect to diagnosis, treatment, and prognosis of the disease, compared to casual and self-measured blood pressure.