In one embodiment, a medical system includes a catheter configured to be inserted into a body part of a living subject, and including a deflectable element having a distal end, an expandable distal end assembly disposed at the distal end of the deflectable element, and comprising a plurality of electrodes, a distal portion, and a proximal portion, and configured to expand from a collapsed form to an expanded deployed form, and a stretchable irrigation tube disposed between the distal portion and the proximal portion, and comprising a plurality of irrigation holes, and configured to stretch longitudinally when the distal end assembly is collapsed from the expanded deployed form to the collapsed form.