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Gorlin first coined the term "counterpulsation" to
describe the two-fold effect of the rapid displacement and reduced
resistant of volume in the lower arterial circuit. The principle thought
to be in effect is that via persistent augmentation of diastolic flow,
stimulation of collaterals to ischemic territories occurs with improvement
in symptoms and clinical measures of ischemia. It has been shown that
external counterpulsation improves ischemic physiology by increasing
myocardial oxygen supply (with increased diastolic perfusion pressure) and
reducing cardiac workload by decreasing left-ventricular afterload
Adrian Kantrowitz began initial clinical work
with an internal system in 1968 with a 15 French device which was employed
via a surgical approach using a chimney graft on the femoral artery This
technique developed into the modern intra-aortic balloon pump which is
part of the standard armamentarium of cardiologists and cardiovascular
surgeons today . The present day intra-aortic balloon pump is available in
8 French and 9 French sizes and can be placed via a transfemoral approach
in 90-95% of patients where coronary perfusion or cardiac assist is
needed.
Soroff and Birtwell first described how the
application of a positive pressure pulse to the lower extremities during
diastole could raise diastolic pressures by 40 to 50% and lower systolic
pressures by up to 30% (5, 6). By the early
1960's, three groups (Birtwell and Soroff, Dennis, and Osborn)
independently developed hydraulically activated external counterpulsation
devices. They found that the technique was effective in improving survival
after myocardial infarction complicated by cardiogenic shock
(5, 6). Initial experience with a crude
external counterpulsation device used in stable angina saw relief of
angina symptoms with angiographic evidence of increased vascularity
(7). In a large randomized trial, 258 acute
myocardial infarction patients were assigned to treatment with external
counterpulsation for three hours within 24 hours of presentation reduced
mortality significantly in patients over 46 years of age (8.3% vs. 17.5%,
p < 0.05) (8). Despite some of these very
positive early findings, other studies showed no benefit with external
counterpulsation as it was studied in the 1970's and 1980's. The great
variability in the clinical benefit found seemed to correlate with the
level of diastolic augmentation achieved.
In the early 1980's, a Chinese group lead by Z.S.
Zheng began reporting a large experience using a sequential three-cuff
external counterpulsation system which provided a pressure wave by
sequentially inflating from calf to thigh to buttock (Figure 1)
(9, 10). Their clinical experience led to the
installation of more than 1,500 external counterpulsation units in China
during the past 15 years leading to the development and refinement of the
EECP technique and device.
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