Palpitations in pacemaker patient

A 53-year old male, implanted with a dual-chamber device, was admitted to the surgery department because of elective inguinal hernia repair. 

Two days after the surgery he was planned to be released from the hospital when he complained of regular palpitations and the following ECG was made.

What do you see? Do you recommend any changes in device programming?

Physician advice: 
Trace category: 

Sino atrial block

Yes or sinus pauses. Pacemaker intervenes with AP after what appears to be 1200 ms (50 bpm). Since the patient felt palpitations, we increased the lower rate which ablosved his symptoms.