Consecutive interval counting

As its name implies, a consecutive interval counting scheme requires that a certain number of ventricular beats occur consecutively and are classified to a tachycardia zone in order to satisfy detection criterion. This number is programmable. For example if the number of beats needed to detect is 10, then 10 consecutive tachycardia beats are required to satisfy detection. Each interspersed non-tachycardia beat causes counting to be reset to zero. It is common to find this method of counting in VT detection zones. Exceptions include Guidant ICD models that utilize an "X of Y" counting method in their VT zones of detection, and Medtronic models where the physician has the choice of a consecutive interval or an "X of Y" counting scheme in the "Fast" VT zone. 

Counting in a consecutive interval scheme is reset to when a... 

Therapy, since neither white cell nor platelet count are raised, is venesection at whatever interval necessary to maintain packed cell volume between 40% and 45%. If this continues long enough iron stores will be depleted and the time between consecutive blood collections is extended. This deficiency state should not be corrected except in the very rare circumstance of paradoxical hyperviscosity where symptoms are related to the poor deformability of the hyprchromic and microcytic red cells in the microcirculation. Where possible, underlying medical illnesses such as cardiopulmonary disease, should be corrected and the patient advised to stop smoking. In those individuals where respiratory function is normal during the day it is necessary to repeat this whilst asleep at which time the hypoxic stimulus may be revealed. 

The time of return can itself be made the criterion of success, by forgetting about the B region and counting two consecutive crossings of S as independent transitions if and only if they are separated by a time interval greater than some characteristic time To, e.g. the autocorrelation time of the velocity normal to... 

In the shuttle box the acquisition of a two-way CAR was analyzed during 5 consecutive days. The rat was put in a box divided inside into two parts by a barrier with a small gate in the middle, and the animal was trained to cross the barrier under the influence of a conditioned stimulus (CS, fight flash). If it failed to respond within 5 s, it was punished with an unconditioned stimulus (US), a footshock (1 mA). If the rat failed to respond within 5 s to the US, it was classified as an escape failure (EF). One trial consisted of a 15 s intertrial interval (IR), followed by 15 s CS. The last 5 s of CS overlapped the 5 s of US. At each learning session, the number of CARs, EFs and IRs were automatically counted and evaluated by multi-way ANOVA. 

Figure 26. (A-G) Seven consecutive images recorded from the marked square section of Figure 24. The time interval of successive records is 13 min. In order to eliminate pixel-to-pixel counting statistical noise, the data have been smoothed with a Gaussian filter (half-width of 3 pixels) at the cost of spatial resolution. The intensity changes of individual molecules from image to image (e.g. molecules labeled 1 and 2) and their lateral displacement (molecules in 3) are striking. (H) Trajectories of the marked molecules. (Adopted from [92].)...

The two can be related using a concept called a Poisson process. From the Wikipedia s article on the Poisson Process In probability theory, a Poisson process is a stochastic process which counts the number of events and the time that these events occur in a given time interval. The time between each pair of consecutive events has an exponential distribution with parameter G the parameter is the occurrence rate per unit time] and each of these inter-arrival times is. .. independent of other... 

In order for the blank run to be valid, it must meet the drift requirement specified in 8.3. In addition, no peaks must be found such that the difference in area readings per second in consecutive time intervals be greater than five times the noise. If the noise is not detectable, assume it to be 1 count per second. 

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