Abstract: In one exemplary mode, a medical system includes an ultrasound probe configured to captured ultrasonic images of at least part of a body part of a living subject, a display, and a processor configured to render to the display respective representations of respective electro-anatomical data subsets superimposed over respective ones of the ultrasonic images.

Abstract: In one embodiment, a medical system includes a catheter configured to be inserted into a cavity of a body of a living subject, and including an inflatable balloon comprising electrodes, the inflatable balloon being configured to press the electrodes against tissue of the cavity and at least partially block blood flow in the cavity, an ultrasound probe configured to provide velocity measurements of the blood flow in the cavity over time, a processor configured to assess a quality of contact of the electrodes with the tissue responsively to at least one of the velocity measurements of the blood flow in the cavity, and output an indication of the quality of contact to an output device, and a power supply configured to provide at least one electrical signal to the electrodes in order to ablate the tissue of the cavity.