Researchers Too Quick to Blame Steroids for Changes in Heart Muscle

Left ventricular wall thickening does occur in elite power athletes with or without anabolic steroid use.

Researchers:

Dickerman RD, Schaller F, McConathy WJ
Department of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, Tex., USA.

Source:

Cardiology 1998 Oct;90(2):145-8

Summary:

Researchers examined 4 elite resistance-trained athletes by two-dimensional echocardiography. In addition, they retrospectively examined the individual left ventricular dimensions of 13 bodybuilders from our previous echocardiographic studies. All 4 elite resistance-trained athletes had left ventricular wall thicknesses beyond 13 mm. One of the elite bodybuilders has the largest left ventricular wall thickness (16 mm) ever reported in a power athlete. Retrospectively, 43% of the drug-free bodybuilders and 100% of the steroid users had left ventricular wall thickness beyond the normal range of 11 mm. In addition, 1 drug-free subject and 3 steroid users were beyond the critical mark of 13 mm. No subjects demonstrated diastolic dysfunction. In contrast to previous reports, we have demonstrated that left ventricular wall thicknesses >/=13 mm can be found routinely in elite resistance-trained athletes who do not use anabolic steroids.

Discussion:

Left ventricular hypertrophy is characterized by thickening of the left ventricular wall secondary to cardiac fiber enlargement. Left ventricular hypertrophy is normally caused by a chronic increase in systemic blood pressure. It may also be seen with sudden or rapid weight gain. The thickening of the ventricular wall due to increased afterload from elevated vascular resistance can be viewed as adaptive protection up to a point. Beyond minor wall thickening, left ventricular hypertrophy is a strong predictor of serious cardiovascular risk.

During heavy lifting, systemic blood pressure is increased from what is called the valsalva maneuver. It is simply the act of forceful expiration with the mouth and nose closed producing a “bearing down” on the abdomen. Pressure also increases due to blood vessels being occluded by contracting muscles. It should be noted that the LVH seen in bodybuilders and power lifters is called “concentric left ventricular hypertrophy”, meaning that it is the result of contracting against acute increased systemic pressure, and was not considered pathological. “Eccentric” LVH is caused by constant increases of blood pressure not as a result of the valsalva maneuver but instead clinical hypertension that forces the ventrical to expand against resistance. It was previously believed that the intermittent increase in blood pressure that is caused by heavy lifting was not sufficient to elicit left concentric ventricular hypertrophy (CLVH). Any evidence of CLVH in strength athletes or bodybuilders was seen as a sign of anabolic steroid use.

In the study above researchers identified LVH at or beyond 13mm in not only bodybuilders using anabolic steroids but also in “drug free” athletes as well. Although it was shown that those using anabolics showed significantly more ventricular thickening, at least one drug free athlete was beyond the 13mm limit.