A new method of mechanical circulatory support with an implantable multichamber pump system (IMPS): presentation and first experimental results.

This paper presents a new cardiac support device for left ventricular failure which consists of two inflatable bellows positioned dorsally and ventrally to the left ventricle. The implantable multichamber pump system (IMPS) is driven by a pneumatic pump system and controlled by a microcomputer using ECG-trigger and pacemaker modules. It was implanted via thoracotomy in 8 pigs. The circulatory parameters were measured in the animals on beta-blockers, with cardiac failure and in ventricular fibrillation with an activated (IMPS on) and deactivated (IMPS off) system. IMPS significantly increased the left ventricular pressure (LVPsys IMPS off: 63 +/- 6 mmHg vs IMPS on: 96 +/- 8 mmHg) and the blood pressure in the common carotid artery (BPca, IMPS off: 69/38 mmHg vs IMPS on: 95/40 mmHg). The IMPS proved to be highly efficient in the therapy of animals with acute cardiac failure and in ventricular fibrillation in the experimental model. Apart from its efficiency the advantages with this system are the ease of handling and its high biocompatibility due to the lack of contact with circulating blood.