Relation between Serum Carboxy-Terminal Propeptide of Type 1 Procollagen(PIP), a Marker of Myocardial Fibrosis, and Left Ventricular Diastolic Function in Patients with Early Type 2 Diabetes Mellitus

ABSTRACT

BACKGROUND AND OBJECTIVES: This study was designed to investigate whether the serum concentration of the carboxy-terminal propeptide of procollagen type I PIP, a marker of myocardial fibrosis, was related to the change of the ventricular filling dynamics in patients with early type 2 diabetes mellitus (DM). SUBJECTS AND METHODS: Echocardiography was performed in 28 patients with type 2 DM and 32 age-matched healthy controls, ranging from 31-69 years of age, with normal left ventricular (LV) systolic function and ECG at rest. Subjects with diabetic complications, including microalbuminuria, nephropathy (Cr>1.3 mg/dL), severe obesity (BMI> or =30 kg/m2), LV hypertrophy (LV septal thickness and/or posterior wall thickness 12 mm on M-mode) and hypertension, were excluded. The serum concentrations of PIP and Transforming growth factor TGF-beta1 were measured by enzyme immunoassay methods. RESULTS: The type 2 DM group had lower mitral (Type 2 DM vs. Control 0.88+/-0.28 vs. 1.17+/-0.34, p<0.01) and tricuspid E/A ratios (1.15+/-0.25 vs. 1.30+/-0.25, p=0.01) than the control group. The level of serum PIP was higher (p<0.05) in patients with type 2 DM than in the control group (131.1+/-45.6 vs. 109.3+/-32.5). The difference in the duration between transmitral forward (A) and pulmonary venous retrograde (Ar) waves (A-Ar) was considered an estimate of a passive diastolic function. A-Ar was inversely related with the serum PIP level in type 2 diabetes (r=-0.43, p=0.03). CONCLUSION: These results show a relationship between the LV diastolic function and the serum concentration of PIP in early type 2 DM. These findings suggest that the determination of the serum level of PIP is a useful method for the screening and early diagnosis of myocardial fibrosis associated with DM.