Soon to be interventional fellow here. I agree there comes a time when reimbursements become so low that they don't justify the sacrifice required re deferred compensation, sleep deprivation, work hours, family sacrifice, radiation / needlestick risks, etc. Each person has to decide where that threshold is for themselves, given how much they do or don't like they're job.
However, there are perhaps a handful of specialties which have the dramatic and often immediate results that we see in cardiology. Have you ever seen an STEMI during your CCU time in residency where a patient came in with recurrent electrical / hemodynamic instability, made it to the cath lab on death's door, and with a combination of primary PCI, adjunctive mechanical support, and appropriate CCU management left the hospital neurologically intact and mostly fully functional ? What about a patient who comes in in 3rd degree heart block unconscious and as the cardiologist on call you can fix the situation in a few minutes by placing a temp wire. If those sorts of situations / outcomes are not rewarding enough to you to justify the additional training, then maybe cardiology isn't for you.
On top of that, cardiology is the most data driven specialty out there... we basically invented clinical RCTs. So despite the rare bad apple who is putting in inappropriate stents or some such thing, what you do is data driven and has clear demonstrated benefit - that can't be said of many treatments in other specialties.
Do I wish that CMS would stop the ridiculous onslaught of dropping reimbursements for what we do (and physicians in general, which are clearly not the reason costs are increasing)? Of course, its a slap in the face to do 7 years of PGY training and have to justify every decision you make, and then be reimbursed based on some arbitrary / flawed decision making at the medicare / insurance level.
But if you think the grass is greener elsewhere, if CMS keeps cutting reimbursement for cardiac procedures with documented significant benefit in RCTs, how long do you think they'll keep paying for bunk therapies like kyphoplasty, where RCTs show zero benefit?
Bottom line, I hate that they keep cutting reimbursements, but the job is rewarding enough that I wouldn't consider doing anything else.