Non-predictors of appropriate therapy
Whilst there were many positive predictive variables associated with appropriate therapy in the above works, Azoulay et al. also identified other factors that were not associated with receiving appropriate therapy in their meta-analysis. These were LBBB, RBBB, a positive cardiovascular magnetic resonance (CMR) and syncope. Two of the studies included from this meta-analysis had separately analysed factors that were non-predictors of appropriate therapy. The conclusions of these agreed with those from the above meta-analysis, with the exception of having a lower mean LVEF. This was discussed in Taha et al.’s review(6): “One found that extent of cardiac involvement on CT-PET and pre-procedure ventricular arrhythmia (VA) burden were non-predictors(15). The other described being >60 years old, New York Heart Association (NYHA) class III/IV, LVEF <35%, non-sustained VT, paroxysmal atrial fibrillation (AF), QRS interval >150ms, QTc interval >470ms and concurrent amiodarone therapy as non-predictors of appropriate therapy(16)”.