What if all these coronary procedures didn't really help anyone?
It looks like the state-of-the-art procedures for preventing coronary episodes don't do more than alleviate symptoms. And haven't for fifty years, going back through several layers of procedures.
The advent of angioplasty in the 1980s complicates the story. With angioplasty, instead of bypassing the plugged artery, “you use a balloon to compress the plug,” Jones explains, “and (as it’s done today) you leave a stent behind to keep the blood vessel open, and so restore blood flow to the heart.” Like bypass surgery, angioplasty went from zero to 100,000 procedures annually with no clinical trial to assess long-term outcomes—based on the logic of the procedure and patients’ reports of how much better they felt. Yet the first clinical trials, which appeared in the early 1990s, showed no survival benefit of elective angioplasty as compared with medication.
Moreover, because such trials assess patients’ outcomes several years after their treatments, they often end up reporting the results of outdated procedures. “A clinical trial on angioplasty published in 1992 might study a group of patients who had the procedure in 1985,” says Jones. “But angioplasty has been refined since 1985. So you start another trial in 1992 and publish in 1998; then, the cardiologists say, ‘Now we have fancy stents, not those old-fashioned stents they used in 1992.’ And so on. As long as you continue to innovate in a way that, at face value, looks to be an improvement, the believers can always step out from under the weight of negative clinical experience by saying that the research necessarily applies to an earlier state of medical technology.”