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a Schematic of Leonardo da Vinci's glass model of leftheart aortic track. b Detailed schematics and instruction for constructing artificial heart valves for the glass model by Leonardo. (Detail of RL19082 recto-Courtesy of The Royal Collection Ó 2002, Her Majesty Queen Elizabeth II)

a Schematic of Leonardo da Vinci's glass model of leftheart aortic track. b Detailed schematics and instruction for constructing artificial heart valves for the glass model by Leonardo. (Detail of RL19082 recto-Courtesy of The Royal Collection Ó 2002, Her Majesty Queen Elizabeth II)

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Leonardo's studies of cardiovascular systems, in more than 50 surviving pages from two phases of his research (around 1508-1509 and 1513), are a clear demonstration of his observational genius and progressive deduction of cardiac mechanics and the vascular system. He carried out a detailed hemodynamic study of the aortic valve motion and the role o...

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... exploration of the vortex formation in the Sinus of Valsalva. On this folio he writes, ''A mould of gypsum to be inflated inside with thin glass and then break it from head and foot. But first pour the wax into the gate of a bull's heart, that you may see the true form of this gate'' (O'Malley andSaunders 1983, Kemp 1989). On the same page (Fig. 2b), he demonstrated the design for the construction of an artificial heart valve; an innovation by itself that waited 500 years to be emu- lated. Incidentally, we know that he used an injection technique to make a wax cast of the ventricles of an ox brain ( Keele and Pedretti ...
Context 2
... evidence for glass model studies by Leonardo is reinforced by the recent flow imaging results obtained in Gharib's laboratory through laser-based imaging tech- niques, (see Fig. 4). A glass model of the aortic track is constructed according to Leonardo's schematic in Fig. 2a. The flow enters from a reservoir, simulating the heart, and the pulsating flow signature of the heart is simulated using a pulsatile pump connected to the outlet of the glass model. Using laser sheet illumination, particle streak imaging reveals the qualitative flow patterns, whereas Doppler particle-imaging velocimetry (DPIV; Gharib ...

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