Intracoronary serum smooth muscle myosin heavy chain levels following PTCAmay predict restenosis

Recently a novel biochemical method that uses an immunoassay to quantitate serum smooth muscle myosin heavy chain (SMMHC) levels was developed for dia gnosis of aortic dissection. The purpose of this study was to determine whe ther SMMHC released from the coronary arterial wall can be used to predict restenosis after percutaneous transluminal coronary angioplasty (PTCA). Fif ty-two consecutive patients undergoing successful PTCA for single vessel di sease were examined (40 men, 12 women, 63+/-8 years). Intracoronary blood s amples were obtained distal to the lesion, and from the femoral artery afte r PTCA. In 10 patients, blood samples were taken immediately after the fina l balloon inflation, and 10 and 20 minutes after PTCA. SMMHC levels were me asured by ELISA using SMMHC-specific monoclonal antibodies. Follow-up coron ary angiography was performed 3 months after PTCA. Intracoronary serum SMMH C levels were significantly higher than those obtained from the femoral art ery (10.6 +/- 1.5 vs 2.1 +/- 0.1 ng / mi, p less than or equal to 0.001), O f 40 patients without apparent dissection, the 23 patients who did not deve lop restenosis in the follow-up study were found to have had higher levels of intracoronary SMMHC levels immediately after PTCA compared to the 17 pat ients with restenosis (15.2 +/- 2.9 vs 7.1 +/- 1.2 ng/mi, p less than or eq ual to 0.05), We suggest that elevated intracoronary SMMHC levels after PTC A may reflect the extent of injury to the arterial wall. Intracoronary SMMH C may be a possible biochemical marker for the prediction of restenosis.