Phrenic nerve stimulation with the quadripolar left ventricular lead not overcome by 'electronic repositioning'.

Phrenic nerve stimulation (PNS) is a frequent occurrence in patients implanted with a cardiac resynchronization therapy (CRT) device. The quadripolar left ventricular offers 10 pacing configurations which can overcome PNS in most cases. We report a rare case of significant PNS following upgrade to a CRT which was present with all 10 pacing configurations one day following implantation which required lead repositioning.