To acquire the %CRT there are two methods. The most visual is probably the % pacing curve as shown below under the Summary screen. The parallel curves of atrial heart rate (top) and time in AF (bottom) confirm the strong negative relationship in (paroxysmal) AF and % CRT in patients with preserved AV conduction. We also observe that %CRT is currently closer to 0% due to a longer period of AF, which when longer than a month, is often called persistent AF.

A more detailed look may be acquired by clicking on PM/ICD -> Statistics

Here we can confirm that occurrence of AF is associated with complete loss of CRT in this patient.

Evaluation of registered EGMs confirmed the diagnosis.

While AF may self-terminate and it may be decided to accept the current situation and wait for the AF episode to terminate, this will unlikely help the current patient who is symptomatic and has already had AF for several weeks. It was decided to perform an external cardioversion (by shock) to terminate the AF episode and plan AF ablation.