The Journal of Thoracic and Cardiovascular Surgery, Vol 73, 550-558, Copyright © 1977 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
An aortic--left ventricular pulse duplicator used in testing prosthetic aortic heart valves
JF Cornhill
A pulse duplicator for the testing of prosthetic valves has been produced
which accurately simulates physiological pressure and flow wave forms in
the left ventricle and ascending aorta. The model consists of two
components--the ventricle and the artificial systemic circulation. The
ventricle is a collapsible bag which is externally pressurized and produces
an accurate ventricular pressure-time history. The artificial circulation
is externally pressurized and produces an accurate ventricular
pressure-time history. The artificial circulation is a development of the
lumped parameter model of Westerhof13 in which the physiological input
impedance is modeled by a characteristic resistance, a capacitance, and a
peripheral resistance connected in series. The model allows for a wide
range of heart rates, systolic- diastolic ratios, mean pressures, flow
rates, and fluid viscosity. A Fourier analysis of the model pressure and
flow waves shows excellent quantitative agreement with physiological data,
as does the vascular input impedance. The Oxford aortic heart valve
exhibited a regurgitation of 1.9 per cent and no measureable pressure drop
or power loss.
