PMC5420026_01
Subcutaneous implantable cardioverter-defibrillator interrogation strip displaying patient in sinus tachycardia. Overcounting and inappropriate therapy resulted from signal rectification in the presence of tall R waves and shift in baseline.
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PMC5420026_01_gr1.jpg
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This led to a shift in the baseline and predisposed the patient to double counting and oversensing (Figure 1).
Alternate vector selection with lowest amplitude R wave.
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PMC5420026_01_gr2.jpg
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The device was reprogrammed to the alternate vector with smallest amplitude QRS (Figure 2), and device function was confirmed in different positions as well as with exercise.