Complementary Alternative Cardiovascular Medicine

Chapter 13 / Energy Medicines and Therapies 207
actual necrosis. A study of short-term exposure of unorganized bovine
aortic endothelial cells to weak, low-frequency EM fields resulted in
their reorganization into complex three-dimensional structural vessels
(26). Low-frequency EM fields have been noted, as discussed previously,
in selected animal studies to induce angiogenesis both in vitro and
in vivo, suggesting that EM fields may be useful in reducing ischemiainduced
myocardial damage.
Effects of Acoustic Energy on Cardiovascular Disease
Soundmyography has been used to detect and measure sound emissions
from the body (27), suggesting that extrinsic acoustic energy therapies
may have direct biological effects. Acoustic energy can be delivered
in the form of mechanical vibrations, which generate sound waves, and
is primarily characterized in terms of its frequency relative to the auditory
range (20 Hz to 100 kHz). Ultrasound uses frequencies higher than
this range, and infrasound uses frequencies lower than this range. Sound
therapy uses auditory range acoustic energy, which is not FDA regulated.
A growing body of in vitro and animal research has addressed the
scientific basis for the therapeutic application of low-intensity acoustic
energy. This research area, bioacoustics, is now the subject of scientific
inquiry (28) and the focus of a professional society: The Acoustic Society
of America. Selected bone-healing experiments have indicated that
acoustic energy produced effects similar to those observed with EM
fields and that mechanical vibrations, generated from a noise generator,
produced protective effects against subsequent hypoxic stress, as has
been noted with EM fields (29).
THERAPEUTIC ULTRASOUND AND INFRASOUND
Selected animal studies have indicated that ultrasound energy may
stimulate angiogenesis as has been noted with EM fields. One study
using a wound-healing model in rats demonstrated that that after 5 d of
ultrasound (100 mW/cm 2 , 750 kHz) treatment there was a significant
increase in new blood vessel formation (30). A recent report noted the
efficacy of low-intensity ultrasound for 2 wk to promote the healing of
pressure ulcers in patients (31).
One study in rats directly applied ultrasound to cardiovascular tissue
and evaluated changes in cardiac function. Rat hearts were subjected to
ultrasound (2 W/cm 2 , 1000 kHz) for 15 min and ventricular pressure and
pressure time intervals were measured. There was no noted effect of
ultrasound to improve healthy isolated heart hemodynamic performance
(32). In contrast, studies in Russia using long-term treatments with 8 Hz
infrasound have produced preliminary evidence for increased myocar-