Noninvasive Central Blood Pressure Measurement: Changing diagnosis, drug therapy management—and patient lifestyles

Noninvasive Central Blood Pressure Measurement: Changing diagnosis, drug therapy management—and patient lifestyles

In physician practices throughout the country, a new method of assessing cardiovascular risk and managing hypertension therapy is being adopted, using the SphygmoCor® system from AtCor Medical, which allows physicians to determine pressures in the ascending aorta through a measurement taken at the patient’s wrist.

Photo caption: Determining the pressure the heart, brain and kidneys actually experience

The SphygmoCor technology, which received FDA marketing clearance in 2002 after demonstrating substantial equivalence to invasive arterial monitoring catheters, has been featured in over 600 peer-reviewed, published studies. 

SphygmoCor is used globally in leading healthcare institutions, including all of the 21 hospitals on the US News & World Reports “Best Hospitals” 2010 Honor Roll, and in leading physician practices and pharmaceutical clinical trials.

In current clinical practice, noninvasive central blood pressure assessment is used to make treatment decisions for patients with high normal brachial blood pressure and resistant hypertensives and to assess the effects of hypertension medications, which can affect central and brachial blood pressures differently.

A recently published article in Mayo Clinical Proceedings describes the benefits of noninvasive central blood pressure assessment as an adjunct to brachial blood pressure measurement: in initiating and monitoring hypertensive treatment, in observing the hemodynamic effects of atherosclerotic risk factors and in predicting cardiovascular outcomes and events.

“First, central aortic pressure is a better predictor of cardiovascular outcome than peripheral pressure. Second, peripherally obtained blood pressure does not accurately reflect central pressure because of pressure amplification. Lastly, antihypertensive medications have differing effects on central pressures, despite similar reductions in brachial blood pressure.”

Mayo Clin Proc. 2010;85 (5): 460-472

The Mayo Clinic has also released an eight minute video on youtube.com, narrated by Jan Stepanek MD, one of the authors of the journal article.  The video demonstrates how the SphygmoCor system is used in the Clinic and presents case studies showing how test results are used to improve patient management.

http://www.youtube.com/watch?v=OOK6T7tCUS4&feature=youtube_gdata

(Click to view video)

A measurement at the wrist derives pressure in the ascending aorta

The SphygmoCor system, which is connected to a laptop computer, uses applanation tonometry to capture the arterial pressure wave form at the radical artery.  After competing brachial cuff blood pressure measurement, the technician finds the strongest pulse point at the radial artery and records ten seconds of radial pressure waves.  The SphygmoCor system instantly derives the central pressure wave forms and indices and displays both radial and central pressure results on the screen.

Displays the patient’s arterial age

Reports generated by the SphygmoCor system display patient demographic data, test quality control criteria and key indices of central pressure.  Patient results are also graphed on an age reference scale which compares individual results with a data base of “normals” of the same gender.

SphygmoCor central pressures and reference age data allow physicians and patients to assess the beneficial effects of drug therapy and lifestyle changes in subsequent testing.

The printable patient reports are a powerful motivator and compliance tool.

New Version 9 Software: Ease of Use

At the American College of Cardiology 2010 Annual Meeting, AtCor introduced SphygmoCor Version 9 with AutoCapture, a new feature designed to make the system easy for practices to use.  During testing, the system automatically captures test results, once acceptable data has been recorded.

The Version 9 system also features re-designed clinical reports for efficient data interpretation, flagging patient results that may indicate increased risk.

Web-based Central Pressures CME Program

The Vascular Biology Working Group (VBWG) offers a complimentary web-based CME program on the emerging role of noninvasive central blood pressure in clinical practices.  The program includes a review of the NIH funded Strong Health Study, which found that when central pulse pressure exceeds 50 mm, Hg the risk of cardiovascular events sharply increases.

(Click to access CME Program)

http://www.vbwgcme.org/program.aspx?cmeid=1128&lname=ALERT

For more information about the SphygmoCor system:

AtCor Medical

One Pierce Place Suite 295-East

Itasca IL 60143

Telephone: 630-228-8871

E-mail:  info@atcormedical.com

Company web site: www.atcormedical.com

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