The analyzed episode corresponds to a relatively slow VT (<150 beats/minute); the first 5 bursts are ineffective while the sixth burst allows termination. It should be noted that an additional stimulus is delivered during each burst so as to increase the aggressiveness of each attempt. It is possible to program a large number of pacing sequences to promote a painless termination. It is important, however, to avoid the delivery of overly aggressive therapies (ramps with very short intervals and large number of stimuli) in order to limit the risk of acceleration of the tachycardia. The programming of electric shock is optional for this type of tachycardia and depends on the tolerability of the arrhythmias.

To optimize the effectiveness of anti-tachycardia pacing in the VT zone, various parameters can be programmed:

1. the type of sequence: in a burst, the duration of the intervals is constant during a sequence (no change in interstimuli rate). It is the most commonly used sequence in clinical practice and probably the least aggressive. According to the new guidelines, the burst should be preferred to other sequence types. In ramp therapy, the interval is reduced from one stimulus to the other by the decrement value which is programmable; it is therefore necessary to program the increment between each interval (programmable between 5 and 40 ms). In a + ES burst (specificity of this manufacturer), at the end of the burst, a short interval pacing stimulus is delivered. This option is no longer available in the Lumax 740 device platform and beyond.
2. the number of programmed sequences varies according to the rate of the tachycardia. In a slow VT zone (<150 beats/minute), a large number of sequences can be programmed in order to delay the delivery of a shock to a tachycardia that does not generally threaten short-term survival. It is also possible to not program an electric shock in this slow VT zone. For tachycardias between 150 and 200 beats/minute, it is common to program 3 to 6 successive antitachycardia pacing sequences.
3. the number of pulses per sequence: on average, 5 to 15 consecutive pulses are programmed in each burst. If the number is insufficient, the pacing sequence may not penetrate the tachycardia circuit and the burst remains ineffective. On the other hand, if the number is too high, the risk is the termination and re-induction of the tachycardia. An additional pacing stimulus can be systematically added from one sequence to another. According to the new guidelines, a minimum of 8 pacing stimuli per sequence should be programmed.
4. the value of the pacing intervals which is programmable between 70 and 95%: the shorter the couplings, the more aggressive the therapy and the greater risk of accelerating the tachycardia. According to the new guidelines, for a burst, an 88% coupling relative to the rate of the tachycardia (calculated over the last 4 intervals preceding the diagnosis) must be programmed.
5. the minimum coupling allows limiting the aggressiveness of a pacing sequence; there is a pacing rate limit that the device cannot exceed (200 ms). When, for example, during a ramp, the minimum coupling is reached, the subsequent intervals are paced with this minimum coupling without additional decrement.
6. the scan decrement; if the rate of the tachycardia remains constant, the second pacing sequence is faster than the first by the decrement value.
7. the pacing site(s) can be programmed; in single- or dual-chamber mode, the pacing is necessarily right ventricular. For a triple-chamber device, the right biventricular or ventricular pacing mode can be programmed. Biventricular pacing appears to be theoretically superior in patients with left ventricular dysfunction, with the majority of tachycardias originating in the left ventricle (less distance between the tachycardia circuit and the pacing site).

The programming is initially empirical but must be subsequently adjusted according to the different arrhythmias recorded by the device and analyzed during patient follow-up, as well as according to the efficacy ratio (episode termination)/deleterious effect (acceleration of the arrhythmia) of a particular type of pacing sequence.