Radiofrequency ablation (RFA) is an important standard therapy for cardiac 
arrhythmias, but direct monitoring of tissue treatment is currently lacking. We 
demonstrate an RFA catheter integrated with polarization sensitive optical 
coherence tomography (PSOCT) for directly monitoring the RFA process in real 
time. The integrated RFA/OCT catheter was modified from a standard clinical RFA 
catheter and includes a miniature forward-viewing cone-scanning OCT probe. The 
PSOCT system was validated with a quarter-wave plate while the RFA function of 
the integrated catheter was validated by comparing lesion sizes with those made 
with an unmodified RFA catheter. Additionally, the integrated catheter guided 
catheter-tissue apposition and monitored RFA lesion formation in cardiac tissue 
in real time. The results show that catheter-tissue contact can be characterized 
by observing the features of the blood and tissue in the acquired OCT images and 
that RFA lesion formation can be confirmed by monitoring the change in phase 
retardance in the acquired PSOCT images. This system demonstrates the 
feasibility of an integrated RFA/OCT catheter to deliver RF energy and image the 
cardiac wall simultaneously and justifies further research into use of this 
technology to aid RFA therapy for cardiac arrhythmias.