A 74-year-old man with a history of inferior myocardial infraction and 45% LVEF underwent implantation of a Reveal DX for the diagnosis of syncope preceded by palpitation. The ECG shows complete right bundle branch block and electrophysiologic studies reveal a HV interval at 63 ms. Programmed ventricular stimulation was unremarkable.
The device automatically recorded an event labelled FVT. The patient remained asymptomatic in the wake of the episode.
The recording was analysed by the cardiologist during a routine ambulatory visit.
The recording and erroneous interpretation of multiple episodes of noise that saturate the device’s memory can be limited by the optimisation of the device’s position at the time of implantation, in order to record ventricular electrograms of high enough amplitude and without prominent cycle-to-cycle variations.
It is also important to a) create a pocket of small enough dimensions to prevent motion of the device, which may promote the oversensing of noisy signals, and b) program the device with a view to minimise oversensing of P and T wave, as well as the likelihood of double counting of the R wave.
