Monitoring plasma cardiac troponin I for the detection of myocardial injury after percutaneous transluminal coronary angioplasty

The objective of this study was to detect myocardial injury defined by an i ncrease of plasma cardiac troponin I (cTnI) following percutaneous translum inal coronary angioplasty (PTCA) and compare plasma cTnI with the risk of c ardiac complications at 30 days. Plasma cTnI, creatine kinase (CR) MB, and total CK were determined in 83 patients before (baseline) and 6, 12 and 24 h after PTCA. Thirty-eight patients underwent conventional PTCA, 39 PTCA-st ent and six rotational atherectomy. Patients with acute myocardial infarcti on (AMI) and increased preprocedural cTnI > 0.8 mug/l were categorized into group 1 (n = 23). The remaining 60 patients (pre-procedural cTnI = 0.8 mug /l) were categorized as follows: group 2 (n = 15) AMI; group 3 (n = 20) uns table angina (UA); group 4 (n = 25) coronary artery disease (CAD). Twelve h ours post-procedure, all three cardiac markers were more frequently increas ed over baseline in group 2 patients (40-60%) compared to patients in group 3 (5-29%, P < 0.03) or group 4 (0.5-5%, P < 0.01). This was also true for patients undergoing PTCA-stent compared to conventional PTCA or rotational atherectomy (27-40 vs. 4-14%, P < 0.02). cTnI was more sensitive (60%) to d etect release of myocardial protein after PTCA compared to total CK (47%) o r CKMB (43%). A moderate increase of cTnl (0.8-1.5 <mu>g/l) in groups 2, 3 and 4 was associated with higher risk of complications 30 days post-procedu re. (C) 2000 Elsevier Science B.V. All rights reserved.