Posición del American College of Cardiology Position Statement
[The following is a position statement initiated by the Hypertensive Diseases Committee of the
American College of Cardiology. Committee members include Edward D. Frohlich, MD, FACC,
Chairman; Robert Wayne Alexander, MD, FACC; Aram V. Chobanian, MD, FACC; Harriet P.
Dustan, MD, FACC; Ray W. Gifford, Jr., MD, FACC; Sheldon G. Sheps, MD,FACC; Jay M.
Sullivan, MD, FACC and H. J. C. Swan, MD, PhD, FACC. Writing Group: Sheldon G. Sheps,
MD, FACC , Lead Author, Thomas G. Pickering, MD, William B. White, MD, Michael A.
Webber, MD, FACC. This statement was approved by the Board of Trustees of the American
College of Cardiology on December 21, 1993 and replaces the 1990 Policy Statement on
Automated Blood Pressure Monitoring. Reprints are available from: Educational Produces Sales
and Marketing; 9111 Old Georgetown Road; Bethesda, MD 20814; 800/257-4740. This
statement was printed in the Journal of the American College of Cardiology 1994;23:1511-3.]
A previous policy statement by the American College of Cardiology (ACC) on automated blood
pressure monitoring (approved December 13, 1985 and reapproved in 1990) made
recommendations for the use of ambulatory blood pressure monitoring in patients with
hypertension, but this technology was considered to be "investigational" and not yet "clinically
applicable" because of problems with the accuracy and convenience of devices and issues related
to cost and fear of abuse. These concerns have been addressed in published reports, and the
Hypertensive Diseases Committee of the American College of Cardiology now recommends
ambulatory blood pressure monitoring as a mature, clinically applicable (useful) technology for
the management of selected hypertensive patients.
Devices and Technology
Ambulatory blood pressure monitoring is a noninvasive technique by which multiple indirect
blood pressure readings can be obtained automatically for periods of 1 to 3 days with minimal
intrusion into the daily activities of the patient (1). The devices are automatic, lightweight and
quiet and use auscultatory or oscillometric methods, or both, to determine blood pressure. Some
auscultatory devices are coupled to an electrocardiogram for the purpose of gating the R waves to
the Korotkoff sounds and reducing error from noise artifact. Solid state equipment is currently
available that analyzes the ST segment and rhythm (Holter) as well as the blood pressure
measurements. Recent comparisons of different ambulatory devices and techniques generally
reveal considerable agreement among devices in general (2-4). The user must apply the
ambulatory blood pressure monitoring equipment with particular attention to technical details.
Rigorous assessment of agreement with a standard sphygmomanometer in the lying, seated and
standing positions is necessary with each individual subject (1). Agreement of sequential readings
to within 5 mm Hg of systolic and diastolic readings, both at the beginning and end of the
ambulatory record, permit the reasonable extrapolation that the intervening blood pressures are
valid. Most of the devices are inaccurate when the cardiac rhythm is irregular, such as atrial
fibrillation or frequent ectopic beats. However, these situations are usually recognized at the
outset because comparison with a standard manometer is difficult or impossible to achieve.
Patient acceptance of this equipment is excellent at the present time. The devices are very safe.
Petechiae and edema distal to the cuff rarely may occur, particularly in patients with vascular
fragility or platelet dysfunction. Dermatitis and ulnar nerve palsy have been reported, but these
complications are very unusual (1). Usually, the patient is asked to keep a detailed activity journal that includes information about physical and mental activity, meals, sleep, medication and other life events to assist in the interpretation of the blood pressure data. The validity of the data is analyzed first by computer and then carefully reviewed by the user.
Standards that specifically address ambulatory blood pressure monitoring are
now available (3,5,6). The 1992 standard of the Association for th Advancement
of Medical Instrumentation (AAMI, 3330 Washington Boulevard, Arlington, Virginia
22201) on Evaluation of Automatic Blood Pressure Devices (5,6) recommends validation
of an automatic electronic device by comparison with either direct, intraarterial
blood pressure measurements or preferably to the noninvasive cuff-stethoscope
technique, based on Korotkoff sounds. It contains detailed recommendations for
populations to be tested, for methods of comparison, statistical analysis of
the data, presentation of the results and criteria for acceptability. Similar
recommendations have been approved by the British Hypertension Society in their
standards document as well (3). Users considering a purchase, as well as instrument
designers, should refer to these standards for the detailed requirements.
Relation of Ambulatory Blood Pressure Monitoring to Office Blood Pressure and Hypertensive
Disease
Blood pressure in normotensive subjects is characterized by a clear circadian pattern. Blood
pressure values tend to peak during the daytime hours and then fall to a nadir after midnight. In
the early morning hours with awakening and resuming activities, blood pressure sharply increases,
with daytime levels being reached within a relatively short period (7). Activity of subjects at the time of blood pressure recording is an important determinant of the level of blood pressure and may affect hypertensive disease (8). Studies have been conducted to determine normative
ambulatory blood pressure profiles (9-12). For example, a meta-analysis has been performed by
Staessen et al. (13). In this meta-analysis of 22 published studies, ambulatory blood profiles were analyzed in 2,638 subjects who were considered to be normotensive by clinical criteria. The 24-h ambulatory blood pressure averaged 117/72 (2 SD) mm Hg (range 97 to 137/57 to 87), daytime
pressure 122/77 mm Hg (range 101 to 143/62 to 91) and nighttime pressure 106/64 mm Hg
(range 86 to 127/48 to 79). The night/day pressure ratio averaged 0.87 (range 0.79 to 0.92) for
systolic and 0.83 (range 0.75 to 0.90) for diastolic pressure. There are ongoing community-based
studies in Europe at the present time that also provide data with regard to normal values and
diurnal patterns (14,15).
Cross-sectional data have clearly shown an improved correlation between ambulatory blood
pressure measurements over office blood pressure values and the presence of target organ
complications of hypertensive disease (hypertensive changes in the heart, kidney, blood vessels
and brain). Relations between the cardiac involvement have been studied most intensively and, in
general, show stronger associations between ambulatory blood pressure (24-h) and left ventricular
hypertrophy. Adding a measure of blood pressure load (percent of elevated systolic and diastolic
pressures during a 24-h study) improves this correlation (8,16-19). The prognostic studies
available, although limited, indicate that ambulatory blood pressure monitoring is superior to
office blood pressure in predicting cardiovascular morbidity (20-22).
Clinical Indications for Use
A Working Group for the National High Blood Pressure Education Program (NHBPEP)
Coordinating Committee produced a consensus document on ambulatory blood pressure
monitoring published in November 1990 (1). Similar recommendations resulted from other
international consensus conferences on indirect ambulatory blood pressure monitoring in 1990
and 1991 and from the German Hypertension League in 1991, and these have been included in the
recommendations of the Fifth Report of the Joint National Committee on the Detection,
Evaluation and Treatment of High Blood Pressure (JNC V, 1993) (23-26). The American College
of Physicians also "support a more circumspect use of such devices for research and for the care
of subgroups of hypertensive patients with specific clinical problems" (27,28).
Cost Considerations
In considering overall cost-benefit relations for drug treatment of hypertension, economic models
emphasize the greater cost in dollars for quality-adjusted life years for treatment of mild
hypertension compared with that for treatment of moderate or severe hypertension (29,30). About
20% of patients considered to have mild hypertension by office values are normotensive on
ambulatory blood pressure monitoring (31-34). Screening strategies that reduce the fraction of
those initially identified as having mild hypertension and needing drug therapy can lead to
substantial reduction in health care costs (35-38) and suggest that appropriately constrained
ambulatory blood pressure monitoring can be highly cost-effective in this strategy. These models
remain to be tested. There is a much smaller proportion of mild hypertensive patients whose blood
pressure is higher outside the office (17,31). Better assessment of subjects with apparent
resistance to therapy and erratic control leads to improved control of blood pressure and practice
efficiencies (39).
Recomendaciones
Ambulatory blood pressure monitoring has become a mature, clinically applicable technology,
with available standards developed by the Association for the Advancement of Medical
Instrumentation and the British Hypertension Society. American and international consensus
meetings have developed clinical indications and guidelines for this procedure.
Referencias
1. National High Blood Pressure Education Program Working Group Report on Ambulatory
Blood Pressure Monitoring. Arch Intern Med 1990;150: 2270-80.
2. White WB, Lund-Johannsen P, Omvik P. Assessment of four portable ambulatory blood
pressure monitors and measurements by clinicians versus intraarterial blood pressure at rest and
during exercise. Am J Cardiol 1990;65:60-6.
3. O'Brien E, Petrie J, Littler W, et al. The British Hypertension Society protocol for the
evaluation of automated and semi-automated blood pressure measuring devices with special
reference to ambulatory systems. J Hypertens 1990;8:607-19.
4. Graettinger WF, Lipson JL, Cheung DG, Weber MA. Validation of portable noninvasive blood
pressure monitoring devices: comparisons with intra-arterial and sphygmomanometer
measurements. Am Heart J 1988;116:1115-60.
5. Association for the Advancement of Medical Instrumentation (AAMI). Electronic or
Automated Sphygmomanometer Standard. Arlington (VA): AAMI, 1992.
6. White WB, Berson AS, Robbins C, et al. National standard for measurement of resting and
ambulatory blood pressures with automated sphygmomanometers. Hypertension 1993;21:504-9.
7. Khoury AF, Sunderajan P, Kaplan NM. The early morning rise in blood pressure is related
mainly to ambulation. Am J Hypertens 1992;5:339-44.
8. White WB, Dey HM, Schulman P. Assessment of the daily blood pressure load as a
determinant of cardiac function in patients with mild-tomoderate hypertension. Am Heart J
1989;118:782-95.
9. Zachariah PK, Sheps SG. Bailey KR, Wiltgen CM, Moore AG. Age-related characteristics of
ambulatory blood pressure load and mean blood pressure in normotensive subjects. JAMA
1991;265:1414-7.
10. O'Brien E, Murphy J, Tyndall A, et al. Twenty-four-hour ambulatory blood pressure in men
and women aged 17 to 80 years: the Allied Irish Bank Study. J Hypertens 1991;9:355-60.
11. Cox J, O'Malley K, Atkuns N, O'Brien E. A comparison of the twenty-four-hour blood
pressure profile in normotensive and hypertensive subjects. J Hypertens 1991;9:S3-6.
12. Gosse P, Lamaison C, Roudaut R, Dallocchio M. Ambulatory blood pressure monitoring.
Values in normotensive patients and suggestions for interpretation. Therapie 1991:46:305-9.
13. Staessen J, Fagard R, Lijnen P, Thijs L, Van Hoof R, Amery A. Reference values for
ambulatory blood pressure: a meta-analysis. J Hypertens 1990;8:S57-64.
14. Staessen J, Bulpitt CJ, Fagard R, et al. Reference values for the ambulatory blood pressure
and the blood pressure measured at home: a population study. J Hum Hypenens 1991;5:355-61.
15. Staessen J, Bulpitt CJ, O'Brien E, et al. The diurnal blood pressure profile. A population
study. Am J Hypertens 1992;5:386-92.
16. Pickering TG, Deveroux RB. Ambulatory monitoring of blood pressure as a predictor of
cardiovascular risk. Am Heart J 1987;114:925-8.
17. Pickering TG. Ambulatory Monitoring and Blood Pressure Variability. London: Science
Press, 1991.
18. Bauwens F, Duprez D, De Buyzere M, Clement DL. Blood pressure load determines left
ventricular mass in essential hypertension. Int J Cardiol 1992;34:335-8.
19. Parati G, Pomidossi G, Albini F, Malaspina D, Mancia G. Relationship of 24-hour blood
pressure mean and variability to severity of target-organ damage in hypenension. J Hypertens
1987;5:93-8.
20. Perloff D, Sokolow M, Cowan R. The prognostic value of ambulatory blood pressures.
JAMA 1983;249:2792-8.
21. Perloff D, Sokolow M. Ambulatory blood pressure measurements, prognostic implications.
Arch Mal Coeur Vaiss 1991;84:21-7.
22. Mann S, Millar-Craig MW, Raftery EB. Superiority of 24-hour measurement of blood
pressure over clinic values in determining prognosis in hypertension. Clin Exp Hypertens
1985;7:279-81.
23. Indirect ambulatory blood pressure monitoring. An international conference. 1-3 March 1990,
Berlin, Germany. J Hypertens 1990;8:SI-140.
24. Second International Consensus meeting on 24-hour ambulatory blood pressure monitoring. J
Hypertens 1991;9 Suppl 8:52-6.
25. German Hypertension League. Statement on ambulatory blood pressure monitoring.
Hochdruckliga Info, Oct. 1991.
26. Fifth Report of the Joint National Committee on the Detection, Evaluation and Treatment of
High Blood Pressure (JNC-V). Arch Intern Med 1993;153: 154-83.
27. American College of Physicians. Automated ambulatory blood pressure and self-measured
blood pressure monitoring devices: their role in the diagnosis and management of hypertension.
Ann Intern Med 1993;118: 889-92.
28. Appel LJ, Stason WB. Ambulatory blood pressure monitoring and blood pressure
self-measurement in the diagnosis and management of hypertension. Ann Intern Med
1993;118:867-82.
29. Weinstein MC, Stason WB. Hypertension: A Policy Perspective. Cambridge (MA): Harvard
Univ Press, 1976.
30. Stason W. Economics in hypertension management: cost and quality tradeoffs. J Hypertens
1987;5:S55-9.
31. Weber MA, Drayer JM, Brewer DD. Automated blood pressure measurements un the
diagnosis of mild hypertension. J Cardiopulmonary Rehabil 1986;6: 125-30.
32. Hoegholm A, Kristensen KS, Madsen NH, Svendsen TL. White coat hypertension diagnosed
by 24-hour ambulatory monitoring. Examination of 159 newly diagnosed hypertensive patients.
Am J Hypertens 1992;5: 64-70.
33. Pickering TG, James GD, Boddie C, Harshfield GA, Blapk S, Laragh JH. How common is
white coat hypertension? JAMA 1988;259:225-8.
34. Pearce KA, Grimm RH Jr, Rao S, et al. Population-derived comparisons of ambulatory and
office blood pressures. Implications for the determination of usual blood pressure and the concept
of white coat hypertension. Arch Intern Med 1992;152:750-6.
35. Coats AJ, Radaelli A, Clark SJ, Conway J, Sleight P. The influence of ambulatory blood
pressure monitoring on the design and interpretation of trials in hypertension. J Hypertens
1992;10:385-91.
36. Krakoff LR, Schechter C, Fahs M, Andre M. Ambulatory blood pressure monitoring: is it cost
effective? J Hypertens 1991;9:S28-30.
37. Pickering TG. In Ref 17:15.5-6.
38. Hayward RS, Steinberg EP, Ford DE Roizen MF, Roach KW. Preventive care guidelines.
Ann Intern Med. 1991;114:758-83.
39. Grim JM, McCabe EJ, White WB. Management of hypertension after ambulatory blood
pressure monitoring. Ann Intern Med 1993;118:833-7.
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