Had my single pilot cat revoked due to a heart condition (only detected by computer analysis of ECG rather than docs looking at print-out) that had existed through all my life and one major prang. In theory, could have caused black outs, but they only happened on Friday nights a long time ago. Referred to civvy docs who operated (key hole surgery) and fixed in no time. Took over a year for medical board to be convened to finally give my cat back, but by then I was in a ground job. While I was still waiting for the axe to drop as an F3 instructor pilot, I was still allowed to be captain with a student pilot on board who would presumably bring my body back to earth - just not allowed to fly with navs (blessing in disguise? - banter
). If you're 2-seat pilot already, hopefully there shouldn't be too much impact. Just get it sorted before you go for your ATPL medical.