We investigated the effects of coronary rotational atherectomy (PTCRA) on plasma levels of endothelin-1 (ET-1), atrial natriuretic peptide (ANP), and cyclic adenosine monophosphate (cAMP). We studied 14 patients undergoing PTCRA and compared them with 14 patients undergoing plain balloon angioplasty. Blood samples were taken from the femoral vein at baseline, after the end of the atherectomy, after the first balloon inflation, after the end of the procedure, and 4 hours later. ET-1 increased in the angioplasty group from 6.3 +/- 3.2 pmol/L at baseline to 8.5 +/- 3.9 pmol/L at the end of the procedure (F = 3.83, P = .02), whereas it did not change in the PTCRA group. ANP increased in the PTCRA group from 78.1 +/- 15.7 pmol/L at baseline to 89.7 +/- 24.0 pmol/L at the end of the procedure (F = 6.75, P = .0001), whereas it did not change in the angioplasty group. cAMP decreased in the PTCRA group, whereas it did not change in the angioplasty group. In conclusion, ET-1 increases less, ANP increases more, and cAMP decreases more during atherectomy than during plain balloon angioplasty.