Complementary Alternative Cardiovascular Medicine

Chapter 11 / Acupuncture and CVD 177
electrocardiogram (ECG) data as effect variables. Sham acupuncture
was performed outside the Chinese acupoints but in the same spinal
segment. This design permitted blinding of the observers. By correlating
the results of this trial with the psychosocial testing, detecting whether
such factors influenced the outcome of the acupuncture for the treatment
of angina pectoris was possible.
Third, all patients received traditional acupuncture from a different
acupuncturist; the changes in skin temperature, pain threshold, and pain
tolerance threshold were recorded on the index finger (close to the acupuncture
site) and on the hallux (distant to the acupuncture site). Correlating
results from the two acupuncture trials resulted in “the Rosenthal
effect” from acupuncturist bias being eliminated.
When the results from the first and second parts were correlated, no
significant influence from patient expectation and psychosocial factors
on the antianginal effect of acupuncture was observed. No significant
difference was noted between the effects of the genuine and sham acupuncture
on angina pectoris, both demonstrating a significant effect on
anginal attack rate and nitroglycerin consumption (p < 0.005). Patients
who received genuine acupuncture increased exercise tolerance (p < 0.005),
increased pressure-rate-product (p < 0.05), and had a delayed onset of pain
(p < 0.05), when compared to pretreatment values but not when compared
to sham acupuncture. Because a significant effect of acupuncture
and sham acupuncture was observed, these data do not address the role
of placebo effect.
When the results from the second and third parts of the study were
correlated, a significant correlation was observed between antianginal
and neurophysiological variables: the change in anginal attack rate, nitroglycerin
consumption, exercise tolerance, and pressure-rate-product correlated
significantly to the change in local skin temperature. This
correlation was absent regarding change in remote skin temperature and
change in pain thresholds locally as well as remotely (all p > 0.1). This
finding suggests a mutual mechanism underlying the antianginal effect
and change in skin temperature, although the same is not valid for change
in pain thresholds. Furthermore, a Rosenthal effect induced by acupuncturist
bias can be excluded, because this effect would have produced a
similar correlation in local and remote change in skin temperature. This
interpretation is underlined by the change in exercise tolerance being
significantly correlated to the change in pressure-rate-product, indicating
that the improvement in exercise tolerance after acupuncture results
from positive hemodynamic alterations. The correlation between the
antianginal effect and change in skin temperature on the index finger was
significant for both sham and genuine acupuncture, suggesting either a
strong placebo effect or that segmental nerve stimulation is important