Understanding 24 Hour Blood Pressure monitor today arterial hypertension (AH) is recognized as a major risk factor for heart failure, myocardial infarction, stroke and kidney failure. Despite broad public awareness of the importance of hypertension as a risk factor for these diseases, the incidence of optimally controlled hypertensive patients, even in developed countries is only about 25%. This is due to several factors such as selection of inappropriate medication, poor subject compliance by the patient, low activity of doctors to achieve target levels of BP, economic and administrative barriers, and not least the impossibility of aggressive monitoring of blood pressure. The last is due to the disadvantages of conventional methods for measuring blood pressure.
♦ Advantages Over Usual BP Measuring
Reliable method for continuous measurement of blood pressure is ambulatory blood pressure monitoring (ABPM). 24-hour ambulatory blood pressure monitoring (ABPM) is introduced as a method for the first time from M. Sokolow. Over the past 25 years it has evolved from purely research method in important clinical tool for the stratification of cardiovascular risk and determine a treatment strategy for patients with hypertension. So, measured ambulatory BP has a number of advantages over usual BP measurement. ABPM makes large number of measurements – 60-80, avoids errors inherent in usual measurement and BP is registered during daily activity and sleep. It can examine the circadian rhythm and it is a better prognostic predictor.
♦ Devices, Procedures, and Data Analysis
Modern devices for measuring and recording the ambulatory blood pressure (monitors) are small enough in size and weight. Measurement of blood pressure is through auscultatory or oscillometric method, both methods have advantages and disadvantages. More important when choosing a monitor, however, is to use validated by the authorized organizations. The study usually lasts 24 hours (for scientific purposes is preferred 48-hour recording), measurements carried out 15 minutes during the active period and 20 minutes in the passive period. The procedure is associated with some discomfort due to which 10-20% of patients (most common adult women) refuse remonitoring. Analyzing the data is fully automated and is done by specialized software. To be considered as valid, the record must contain over 80% satisfactory measurements, which is recorded automatically. Some software allow manually deleting of incorrect readings. The results are presented in tabular and graphic form.
♦ Prognostic Importance of ABPM
In recent years, results came from a number of cross-sectional study, which showed that ambulatory blood pressure monitoring correlates better than usual BP measurement with surrogate markers of damage to target organs in hypertension. Furthermore, many studies assessing clinical outcomes (mortality, hospitalization, frequency of myocardial infarction and stroke) revealed that the prognostic value of ambulatory BP monitoring is greater than that of the usual measurement. The most common indications for the use of ABPM are off isolated office (white coat) hypertension, border hypertension, adult patients suspected nocturnal hypertension, resistant hypertension, pregnancy and hypotension.
Detection and treatment of hypertension is essential for long-term preventing cardiovascular and cerebrovascular complications. Aggressive attempts to identify and treat hypertension must be carefully balanced with the risk of unnecessary treatment in patients with isolated office hypertension. ABPM is a valuable method for achieving balance between those risks when deciding to start antihypertensive treatment. The results of recent clinical studies ensure wider use of this method in the near future.