March 22, 2006
Results from the ASTERIOD study, presented last week at the 2006 Scientific Sessions of the American College of Cardiology, promise to change the general thinking of cardiologists regarding the treatment of coronary artery disease.
In this study, over 500 patients with coronary artery disease, as documented by cardiac catheterization and IVUS study ("intravascular ultrasound" - a method of viewing the inside of a coronary artery using a specialized ultrasound catheter), were treated with high-dose rosuvastatin (Crestor, AstraZeneca). With 40 mg per day of rosuvastatin, improvements in cholesterol levels were impressive. The average levels of LDL cholesterol dropped from 130 mg/dL to 61 mg/dL, and average levels of HDL cholesterol increased from 43 mg/dL to 49 mg/dL. More importantly, after 2 years of therapy with rosuvastatin, the volume of coronary artery plaques (measured again by IVUS) was significantly reduced.
For the first time, aggressive therapy with statins was associated with actual regression of coronary artery lesions. However, this was a relatively small study, and importantly, there was no control group. The findings in this study will have to be confirmed in a larger, controlled clinical trial - ideally, one that has an endpoint that measures the clinical significance of any shrinkage in plaque volume.
For most cardiologists, the notion that anything can make coronary artery disease regress is revolutionary. Coronary artery disease, once it starts, has been universally considered to be a chronic, continually progressive disorder. Two years ago, using similar methods, aggressive therapy with atorvastatin (Lipitor) was shown to nearly halt the progression of coronary artery disease. This study, and a few others, led many physicians to adopt the notion that, where LDL cholesterol is concerned, the lower the better.
The ASTEROID study takes this idea to a new level. Average LDL levels in the low 60s have never been achieved before in a clinical trial. It would now appear that, for patients with known coronary artery disease, pushing LDL levels even below 70 might not only be a good idea, it may induce the coronary artery disease to begin to reverse.
It should be noted that rosuvastatin is one of the so-called "super statins," the statin drugs that are especially effective on cholesterol. However, it has been alleged that super statins may cause more side effects than "regular" statin drugs, and indeed the only other super statin to have been marketed ( Baycol) was removed from the market because it caused severe muscle problems in some patients. Rosuvastatin did not cause such problems in patients enrolled in the ASTEROID study, but many remain relatively wary of the super statins.
It is important to realize that the ASTEROID trial was a single-center, non-randomized clinical trial, and therefore is not sufficient to indicate a change in clinical practice. If you are a patient with coronary artery disease, however, you might want to talk to your doctor about the aggressiveness with which your cholesterol levels are being treated, and make sure that - within reason - you are both doing everything you can to get that LDL down, and that HDL up.
For the first time, when patients ask, "Isn't there anything I can do to shrink these coronary artery plaques?" doctors may have to say something besides, "No."