Mintek LV, LV-T 2.10 Adjustment of the PMT Protection Window, Table, AV Delay, Test Method, Termination, Confirmation, Interval Length, Table 22. PMT Test Method

Stratos LV/LV-T Technical Manual 91

Confirmation

When the suspicion criterion has been met, the Stratos CRT-Ps slightly modify the AV delay interval (+ or - 50 ms) for one cardiac cycle. If the Vp-As interval remains stable, a PMT is confirmed. Otherwise, a PMT is not confirmed and the algorithm restarts. Once the PMT algorithm has confirmed a PMT, the cycle is terminated.

The upper interval limit range must be shorter than the limit of the VA delay (350 ms, for example). The test method is based on the length of the pacing interval or the AV delay (refer to Table 22).

Table 22. PMT Test Method

Interval Length	AV Delay	Test Method
> UTI (upper	≤ 200 ms	Increasing the AV
tracking interval)		delay by 50 ms
> UTI + 50 ms	> 200 ms	Reducing the AV
		delay by 50 ms
≤ UTI	≤ 200 ms	Increasing the UTI
		by 50 ms
≤ UTI	> 200 ms	Increasing the UTI
		by 50 ms
> UTI and ≤ UTI +	> 200 ms	Length of UTI = TA
50 ms		+ 50 ms

Termination

Stratos CRT-Ps extend TARP (Total Atrial Refractory Period) for one cycle to equal the V-V interval + 50 ms.

2.10 Adjustment of the PMT Protection Window

The PMT protection window can be automatically adjusted. This automatic adjustment functions in the following manner: