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Anomalous "VVI" pacing of a dual chamber pacemaker when programmed in DDI(R) mode
M Masini1, R Dianda, L Cortigiani
1Cardiology Department, Campo di Marte Hospital, Lucca, Italy.
Abstract:
We describe the case of a dual chamber rate responsive pacemaker (Relay, model 294-03, Intermedics, Angleton, TX, USA) implanted in a 68-year-old male for sick sinus syndrome, which was not working properly when programmed in the DDIR mode, thus determining occasionally a sort of "VVI" pacing. However, the pacemaker performed well when programmed in the DDDR mode. We discovered that this was not a malfunction of a single device but rather a general behavior of this family of Intermedics dual chamber pacemakers (also not rate responsive), caused by a software problem.
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