A 39-year-old man is referred to the EP clinic because of occasional episodes of palpitation since his early twenties:

• Sinus rhythm
• Wolff-Parkinson-White  

EP studies reveals a left lateral bypass tract that is successfully ablated. The following ECG is recorded shortly after ablation:   

• Sinus rhythm with sinus arrhythmia
• One premature ventricular complex
• First degree AV block
• Incomplete right bundle branch block (iRBBB)