Relationship between serum amino-terminal propeptide of type III procollagen and changes of left ventricular function after acute myocardial infarction

Background-The amino-terminal propeptide of type III procollagen (PIIINP) is a marker of type III collagen synthesis, which has previously been shown to correlate with infarct size in nonthrombolyzed myocardial infarction (MI) and to provide prognostic information after MI. Methods and Results-The relationship between PIIINP and changes of left ventricular (LV) function was studied in 47 consecutive patients with first acute MI and 16 control subjects. Serum PIIINP analysis was measured daily during hospitalization and on days 90, 180, and 360. LV function was assessed by echocardiography on days 1, 5, 90, and 360. Patients with MI were stratified according to their serum PIIINP value at day 4 (group A, less than or equal to 5.0 mu g/L; group B, >5.0 mu g/L). On arrival, LV function and size were comparable between groups A (n=31) and B (n=16). LV ejection fraction, initially depressed (day 1: group A, 47+/-7% versus group B, 47+/-8%; P=NS), increased significantly in group A (day 360, 54+/-8%, P<0.001) but was unchanged in group B (day 360: 43+/-8%, P=NS). LV volumes increased significantly in group B (P<0.05) but not in group A. Furthermore, patients in group B developed signs of restrictive LV diastolic filling. Multivariate regression analysis identified PIIINP >5.0 mu g/L and deceleration less than or equal to 140 ms as independent predictors of cardiac death or complicating heart failure during follow-up. Conclusions PIIINP assessed in the subacute phase of MI relates to long-term changes of LV function and provides clinical prognostic information.