Stratos LV/LV-T Technical Manual 81

2.3.12 Ventricular Blanking Period

The ventricular blanking time is the period after an atrial pacing pulse during which ventricular sensing is deactivated. It is intended to prevent ventricular sensing of the atrial pacing pulse (“crosstalk”).

The blanking time shall be as short as possible in order to provide ventricular sensing when a ventricular depolarization could occur.

Crosstalk may be encountered if a shorter blanking time, unipolar ventricular sensing, a higher ventricular sensitivity (lower value) and/or a high atrial pulse amplitude and pulse width are programmed.

Values between 30 ms and 70ms (30… (10) …70 ms) can be set for the ventricular blanking period. The value should be set as low as possible and yet high enough to ensure ventricular sensing.

However, it must be programmed to ensure atrial pacing is not sensed in the ventricle.

2.3.13 Safety AV Delay

The safety AV delay (set at 100 ms) applies to all dual chamber pacing modes

To prevent ventricular pulse inhibition in the presence of crosstalk, a ventricular pulse will be emitted at the end of the safety AV delay (Figure 5). When pacing is AV sequential at the pre-set safety AV delay, the presence of crosstalk should be considered and appropriate reprogramming performed (lengthen the ventricular blanking time, lower ventricular sensitivity, bipolar configuration, and/or lower atrial pulse energy).