Digital Pulse Analysis in Evaluating Cardiovascular Function

"The Role of Digital Pulse Analysis in Evaluating Cardiovascular Function Following a Six Week Exercise Program"

James A. McHale, D.C. Director, Research and Development Advanced Bioceutical Research, Inc.
Senior Member, Clinical Advisory Board Annasa, Inc.
Chief, Medical Advisory Board The Institute of Weight Management and Health

Dixie Lee Moore, B.S., M.S.
Certified Personal Trainer
Cancer Exercise Specialist

"The Role of Digital Pulse Analysis in Evaluating Cardiovascular Function Following a Six Week Exercise Program"

The purpose of this study was to evaluate the physiologic response of the vascular system to a structured exercise regimen utilizing a fairly new technology known as Digital Pulse Analysis.

Test subjects consisted of sixty-one women, aged 22-80 years, with varying levels of physical conditioning. Baseline pulse analysis results were obtained, and then retested six weeks later.

The D.P.A. (Digital Pulse Analyzer) is an F.D.A. (Food and Drug Administration) approved medical device used for the measurement and analysis of pulse waveforms. The pulse wave is the arterial pressure change that originates from the heart beat, and ultimately transmitted through the arterial system. The index finger is the site of choice. Several factors affect the intensity, form, and quality of these waveforms.

A. Ejection Elastic Index/Left Ventricular Ejection (E.E.I.) represents the ability of the heart to pump and the status of large artery elasticity. A decreased value may correlate with left ventricular ejection insufficiency/atherosclerosis. An increased E.E.I. may indicate increased left ventricular ejection power.

B. Dicrotic Dilation Index (D.D.I.) is a reflection of contractility and stiffness in small arteries. A decreased value may indicate hypertension and/or arterioslerosis (arterial stiffness). An increased D.D.I. is associated with possible arteriole dilation; this corresponds with decreasing vascular resistance.

C. Dicrotic Elastic Index (D.E.I.) reflects peripheral artery/arteriole elasticity. A decreased D.E.I. may indicate decreased blood vessel elasticity-also referred to as arteriosclerosis. An increased D.E.I. is associated with possible arterial dilation.

** The more elastic a vessel becomes, the more efficiently it expands and contracts. As it dilates, it allows a greater flow of blood and oxygen through. The reverse is also true: as a blood vessel loses its ability to expand and contract, the stiffer it becomes. This stiffness results in less blood flow through the vessel and ultimately to the end organ. The heart must pump harder through this restriction. This process is called "increasing vascular resistance".

The digital pulse analyzer is able to provide additional data:

* Recognition Waveform is an indicator of the accuracy of the pulse wave detection:

**Greater than 80% = good detection

**Less Than 80% = poor waveform recognition---test subject may have cold hands, or pathologic reasons for decreased blood flow to the hands (i.e.: Reynaud's ). An irregular heartbeat may impair the waveform interpretation.

* Ejection (Etc) of left ventricle or cardiac output. Normal ejection time is 260-380 ms.

** Decreased ejection time ( Less Than 260 ms ) = possible hypertension.

** Increased ejection time ( Greater Than 380 ms ) = possible decreased cardiac output due to aortic stenosis.

* Pulse Rate (P.R.) The normal heart rate is usually 60-95 beats per minute.

* Pulse Height (Pulse Amplitude)

** Normal = 2.0-8.0

** Low ( Less Than 2.0 ) = weak, thready pulse; possibly due to decreased blood pressure, decreased blood volume (dehydration), or increased vascular resistance.

** Large ( Greater Than 8.0 ) = bounding pulse; possibly due to fever, hypertension, hyperthyroidism, excessive blood volume, and atherosclerosis.

* APG Pattern = Degree to which a vessel ages.

** A,B = Normal (20-30 years)
** C,D,E = (40-60 years)
** F,G = (70-80 years)

* PTG (Plethysmogram) This waveform reflects the velocity of the pulse wave. The amplitude and timing of the wave ultimately depends on the stiffness of the small vessels and large arterial stiffness.

* APG (Accelerated Plethysmogram) Represents arterial aging. This scale is based on A - G grading. As vessels experience trauma (physical, chemical, etc.) the aging of the vessel increases. As we regress from an "A" pattern (20-30 years) to "G" pattern (70-80 years), a number of changes occur:

1. Endothelial Dysfunction
2. Reduced vessel compliance
3. Elevated blood pressure (arterio/atherosclerosis)
4. Large artery wall thickening
5. Plaque formation (formation calcium)
6. Clinical Events

How serious is the problem of cardiovascular disease in America?

Heart disease is the number one killer in America! According to the American Heart Association, heart disease claims over 500,000 lives in The United States each year. Early detection of cardiovascular disease is crucial to reversing this trend, as are the development and implementation of "cardiovascular friendly" entities. Such entities may include decreasing endothelial (lining of the blood vessels) inflammatory conditions utilizing antioxidants, L-arginine supplementation, and stress reduction programs.

The results of this study quantitate the overall improvement of vascular aging (APG) in women.

Sixty-seven women were screened using the Meridian Digital Pulse Analyzer. Baseline cardiovascular scoring and function were performed via the A-G scale, as well as arterial aging (APG) patterns. These women participated in a structured, weight resistance training program that included warm-up, aerobic exercise, strength training, and cool down, and stretching. The weight resistance component uses circuit hydraulic resistance. Hydraulic resistance is recognized as safe and accommodating to different body types and strength/fitness levels. Pushing and pulling may reduce the potential for soreness and injury. The training program sessions lasted for thirty minutes, three times per week, for six weeks duration.

After six weeks, forty-one of the original group of sixty-seven study participants was retested. Twenty-nine participants improved (71%) an average of 6.3 years (APG pattern). Of the 29 that improved, 13 (45%) also improved at least one letter grade in their cardiovascular function. In the group that did not improve, five (12%) stayed the same, and seven (17%) regressed. The average regression in that group was 4.3 years.

Discussion

It is exciting and encouraging to observe and quantitate positive changes in cardiovascular function in a majority of participants after only six weeks.

Conclusion

Exercise programs that incorporate warm-up, aerobics, resistance training to increase strength, cool down, and stretching seem to be beneficial in improving cardiovascular/arterial function. Digital pulse analysis is an extremely fast, accurate, and reliable indicator of left ventricular ejection, large and small artery elasticity and stiffness, as well as peripheral artery/arteriole elasticity. These data are very important as an adjunct to evaluating exercise programs for their ability to improve cardiovascular disease outcomes, and ultimately reducing cardiac deaths and disability.

Questions or Comments? mrmack2@yahoo.com