Dysfunction of CRT-D in acute myocardial infarction: is there a place for programing?

Abstract

The article describes a clinical case of a patient with a previously implanted cardiac resynchronization therapy with defibrillator function (CRT-D). For a long time, the patient was observed in the implanting clinic and the data was also transmitted via remote monitoring. The developing acute myocardial infarction in the right coronary artery caused a change in the parameter of the amplitude of the spontaneous R-wave in the patient. Subsequent ventricular fibrillation (VF) due to stent thrombosis was undetected by the defibrillator and resulted in no detection and cessation of VF, despite the implanted CRT-D. Changing the programming parameters did not affect the possibility of detecting a recurrent VF. The VF that occurred twice was stopped by the first discharge of the external device. In view of the remaining low hyposensing, a decision was made to reimplant the detecting part of the right ventricular electrode, after which defibrillation test proved to be effective for termination induced VF. We believe that at critically low parameters of spontaneous R-wave hyposensing, for the device to detect low-amplitude ventricular arrhythmias, programming the parameters does not solve the problem of hyposensing. Current myocardial infarction as the cause of hyposensing may require active surgical tactics replacement of the pacing and sensing electrode, in cases where the device connector allows this.