A 69 year-old recipient of an EnTrust DR dual chamber ICD, who had a history of myocardial infarction, 35% LVEF and episodes of VT, was seen after receiving a shock while exercising.
In a VT zone >140 bpm, shocks are often programmed in case of unsuccessful ATP. The first shock can be programmed as 1) a 5 to 10 J cardioversion, with the intent of limiting the discomfort caused by the electrical shock, or 2) a maximal output cardioversion to maximize the likelihood of success of a single shock
A VT and a VF detection zone were programmed. An episode of tachycardia was detected in the VT zone and treated; note that, in absence of sudden onset criterion, the therapies were initially withheld. The first 2 therapies were unsuccessful. The 3rd attempt, a 10 j shock, was successful.
