Why the quandry? Because of how permanent atrial fibrillation was defined for the study:
Permanent AF was defined by the presence ofDoes merely electing to not attempt a cardioversion on a patient with atrial fibrillation or atrial flutter truly define "permanent" atrial fibrillation? Not typically - usually we define permanent atrial fibrillation as someone who fails elective cardioversion long-term. But for the intent and purpose of the PALLAS trial on which the "Dear Doctor" letter is based, it is how the "permanence" of atrial fibrillation was defined.
AF/atrial flutter (AFL) for at least 6 months prior to randomization and patient/physician decision to allow AF to continue without further efforts to restore sinus rhythm.
"Persistent" atrial fibrillation are those patients in atrial fibrillation who CAN be converted to sinus rhythm using cardioversion and whose event lasts more than seven days.
Which leads to the logical question: how many "persistant" afib patients were part of the PALLAS patient population and might "persistant" atrial fibrillation patients be similarly at risk?
It's all as clear as mud.