A study published in 1999 in the New England Journal of Medicine continues to produce controversy and infighting among cardiologists. The Atorvastatin VErsus Revascularization Treatment (AVERT) trial compared aggressive cholesterol -lowering (with the statin atorvastatin) to angioplasty in patients with mild to moderate coronary artery disease.
The AVERT study reported that patients ransomized to statin therapy had a lower incidence of later problems (including the need for later angioplasty procedures, coronary-artery bypass operations, and hospitalizations for worsening angina) than did the patients who had received angioplasties.
These results stunned the cardiology community, and since these results were reported, sales of atorvastatin have skyrocketed. However, many cardiologists who make their livings doing angioplasties have gone ballistic. The exchange at heart meetings and in Letters to the Editor sections of cardiology journals have been particularly lively. The most recent volley was fired earlier this month. An editorial in the American Heart Journal strongly criticized the AVERT trial, claiming the study was weak. Included in the complaints about this study were: not enough patients were enrolled for the results to be meaningful; they were the wrong kind of patients to begin with (not sick enough,) and the investigators measured the wrong outcomes. All in all, the editorial concludes, the AVERT trial doesn't tell us anything meaningful about the relative benefits of angioplasty and cholesterol lowering.
Replies to these kinds of criticisms by Dr. Bertram Pitt, chief investigator of AVERT, have been quite consistent. Say what you want about patient selection, the choice of angioplasty procedures, and the aggressiveness of medical management in the angioplasty group - these factors were not dictated by the study, but were chosen by the patients' physicians, and thus reflect clinical cardiology as it is being practiced today. What AVERT shows, therefore, is not whether cholesterol lowering is as good as the best possible angioplasty performed in well-selected patients who also receive the best medical therapy. What it shows is that cholesterol lowering appears to be as effective as angioplasty as it is being practiced in the real world today by American cardiologists.
DrRich Comments:
Critics of AVERT do have some valid points. If many of the patients enrolled in the AVERT trial didn't really need angioplasty in the first place, for instance, then showing that lipid lowering was as good as angioplasty has no meaning - perhaps neither therapy did anything useful for these patients.That's what makes Pitt's response so intriguing. It may not be good medicine the way the angioplasty group was selected, treated, or followed, he seems to be saying, but that's how you guys are practicing.
Reading between the lines, Pitt's response takes us to a place the angioplasty mavens would probably rather not go. Maybe the cholesterol lowering really didn't do that much good. Maybe Pitt could have compared extract of bat wings to angioplasty and gotten equivalent results. But if that's the case, if the study results favored atorvastatin because the angioplasty as performed in this trial wasn't very useful, then the angioplasty community risks being accused of a massive public rip-off. If so, they shouldn't be wasting energy attacking Pitt's study. They should be scrambling to repair their own house before the insurance companies, the feds, and their patients figure out the real meaning of the AVERT trial.
What this means to cardiac patients. If your cardiologist is recommending elective angioplasty for coronary artery disease that is a) not very severe, and b) not very symptomatic, then perhaps you ought to consider getting a second opinion. A second opinion is doubly important if your doctor fails to mention medical therapy as an alternative, or that he/she will be using medical therapy in conjunction with the angioplasty.
Whether lipid-lowering is really as good as angioplasty remains unclear. What is clear is that, whatever therapy is chosen for your coronary artery disease, it had better be chosen carefully and thoughtfully, and not by sheer reflex. A coronary artery blockage is not like Mt. Everest, needing to be dilated "because it's there."
