Ambulatory blood pressure monitoring (ABPM) is a method of taking regular blood pressure readings, usually over a 24–hour period, as patients conduct their normal activities. A special, automatic blood pressure monitor is used, and patients are asked to keep a log of their activities during the day.Ambulatory blood pressure monitoring is usually used when a physician suspects a patient is suffering from “white coat hypertension.” This is a condition in which high blood pressure occurs only in the physician’s office as a result of stress and anxiety.
However, there are a number of other situations that might cause a physician to recommend ambulatory blood pressure monitoring. These include patients who do not respond to medication and patients with symptoms such as fainting. In addition, ABPM has been found to be a more accurate predictor of patients at high risk of a cardiac event than than other blood pressure monitoring methods.
Blood pressure is a measure of the force, or tension, of the blood against the walls of the arteries. High blood pressure puts an added workload and strain on the heart, whereas low blood pressure (hypotension) can lead to fainting. High blood pressure (hypertension) is a very common disease in America. It is considered a major risk factor for heart attacks and strokes.
ABPM measures blood pressure at regular intervals throughout the monitoring period, including at night when the patient is asleep. It then records these measurements. Coupled with the activity log, the ABPM can give a physician a very accurate picture of factors that may be affecting a patient’s blood pressure, such as exercise, eating, medications and certain forms of heart disease.
This information is useful for a variety of reasons. For example, it may help the physician adjust the dosages of antihypertensive medication. Many studies have shown that blood pressure spikes in the morning, right around the time that 24–hour antihypertensives are at their weakest. Thus, heart attacks and strokes may be more likely to occur in the morning. An ABPM could help identify this situation, and the physician could adjust the patient’s medication accordingly.