Q: Which of the cardiac device works on the principle of ancient Archimedes screw?
A) Impella B) Tandem Heart C) Intra Aortic Balloon Pump (IABP) D) Intravenous percutaneous transient pacemaker (IVPM) E) Electrical cardioversion (EC)
Impella is left ventricle to aorta assist device which is a axial flow pump on the principle of an Archimedes screw. The Impella is usually placed percutaneously retrograde via femoral artery across the aortic valve into the left ventricle. A revolving pump draws blood out of the left ventricle (de-loading) and ejects it proximally into the ascending aorta.
The Tandem Heart is a left atrial to aorta assist devices where percutaneous catheter is passed to right atrium and via transseptal puncture into left atrium. Tandem Heart works via centrifugal pump.
IABP works on inflation/deflation principle.
IVPM is an electric pacer and EC is an electric jolt.
1 Siegenthaler MP, Brehm K, Strecker T, et al. The Impella Recover microaxial left ventricular assist device reduces mortality for postcardiotomy failure: a three-center experience. J Thorac Cardiovasc Surg 2004; 127:812.
2. Basra SS, Loyalka P, Kar B. Current status of percutaneous ventricular assist devices for cardiogenic shock. Curr Opin Cardiol 2011; 26:548.