Implantable pulse generator and method having adjustable signal blanking

Abstract

An implantable pulse generator and a method of operation, where the pulse generator is adapted to sense at least a first cardiac signal. Cardiac events are identified in the first cardiac signal, in response to which a blanking interval is started. The blanking interval includes a repeatable noise window blanking interval. When noise is detected during the repeatable noise window blanking interval, the noise window blanking interval is repeated. Depending upon the type of sensed cardiac event (paced or intrinsic) the blanking interval is adjusted to either to a first overall duration or a second overall duration. The second overall duration includes a first timed interval that has a programmable value. The repeatable noise window blanking interval starts after the first timed interval of the second overall duration. The duration of repeated repeatable noise window blanking intervals is summed and compared to a pacing escape interval. When the sum is greater than the pacing escape interval, asynchronous pacing pulses are delivered. When the noise ceases, so does the delivery of asynchronous pacing pulses. Alternatively, when the sum is greater than the pacing escape interval, the pace escape interval is repeated. Pacing is resumed after one pacing escape interval after the noise signal ceases.