The Isolated Heart Size 9 has been developed to perform experiments with hearts from small pigs with a body weight up to about 10 kg (heart weight 40 g). The system can be operated in any one of the three methods (Constant Pressure CP, Constant Flow CF, Working Heart WH). The perfusion flow is limited to 500 ml/min for retrograde perfusion and the aortic flow to 1.5 l/min for a working heart system. The system allows standard haemodynamic as well as ischemia-reperfusion studies using saline or erythrocytes containing perfusion solutions. The complete apparatus is mounted on a trolley. It consists of the jacketed heart chamber, its cover with the connections to the heart, pumps, thermostatic circulator and measuring system.
For heart transplantation and cardioplegia studies, the apparatus is equipped with a special option. With this option the heart can be perfused from a second perfusion circuit in retrograde mode using a different perfusion solution (e.g., perfluorocarbon emulsion). Cardioplegia solutions can be injected or infused through a dedicated port.
• Isolated perfused small pig heart (heart weight up to 40 g) in retrograde perfusion
• Working heart mode, the special flow resistance and compliance chamber mimics closely the in-vivo afterload
• Compact, easy to use
• Special version for cardioplegia studies in heart transplant studies
• Applications: - Studies of recovery in heart transplantation
- Studies of cardioplegia techniques and solutions
- Evaluation of pacemaker
The main part of the apparatus is the cover of the heart chamber. The aortic block is mounted on this cover. In the working heart version the preload reservoir is mounted on the cover and consequently located into the heart chamber. The large heart chamber serves as perfusate reservoir. The chamber can be moved down during the preparation with a lift-system. The way of functioning is identical to the isolated heart system size 5, see page K4.
Saline perfusion solutions are oxygenated by bubbling in the chamber using a frit. If erythrocytes-containing perfusates are used, a membrane oxygenator as used in the heart-lung machine is necessary.
The measured signals as well as the computed parameters in the different modes are the same for the Isolated Heart Setup Size 9 as for the setup IH-SR 5. The size of the flowprobes must be adapted to the corresponding diameters.