Relief For Diseased Hearts
If the heart has been weakened by an infarct or disease, it is often no longer able to provide the body with an adequate supply of oxygen-rich blood. Physicians can use a special type of mechanical pump to support the ailing organ. The degree to which this assistance is needed varies from case to case. Sometimes the pump only needs to give the heart a little bit of help, whereas in other cases it takes over the entire heart function. Because the patient's life depends on the pump, a failure would be fatal. The reliability of the control software is therefore a decisive safety factor.
Cardiac support systems have been in use for 20 years, but those being employed today and their successors have far more software-controlled functions than in the past. "It's a similar development to that of the automobile, where a considerable number of functions now rely on software, such as driver assistance systems. At the same time, the technical requirements for vehicle registration have become more demanding: certain models on sale 15 years ago would not be allowed on the road under today's standards. Exactly the same applies to cardiac support systems," says Prof. Dr. Holger Schlingloff of the Fraunhofer Institute for Computer Architecture and Software Technology FIRST in Berlin. Together with the Berlin Heart company, his team is co-developing a model-based test system to guarantee the functional safety of cardiac support systems. "It is impossible to prove that a system is entirely failure-proof by simply running a test it could be that certain types of fault have been overlooked," says Rolf Hänisch, project manager at the Fraunhofer FIRST. "We can eliminate this shortcoming by producing systematized tests based on models, in which we record and simulate all relevant test scenarios."
There are two approaches to modeling this type of system. The first takes its point of departure in the intended application, asking "how will the device be operated in clinical practice?" and "how does the software interpret the physician's instructions?", for example. The second approach starts by looking at the software's source code, for instance "which part of the code is responsible for which functions?". Since even experts can inadvertently skip a line when reading code, the team has developed an automated program to help them locate safety-critical sections. The new technology will be presented to trade fair visitors at embedded world in Nuremberg from February 26 to 28 (Hall 12, Stand 12-138) and at CeBIT in Hanover from March 4 to 9 (Hall 9, Stand B36).
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Relief pentru inimile bolnave - Relief For Diseased Hearts - articole medicale engleza - startsanatate