Matrix metalloproteinase inhibition attenuates left ventricular remodeling and dysfunction in a rat model of progressive heart failure.

Background: Matrix metalloproteinase (MMP) activation contributes to tissue remodeling in several disease states, and increased MMP activity has been observed in left ventricular (LV) failure. The present study tested the hypothesis that MMP inhibition would influence LV remodeling and function in developing LV failure.

Methods And Results: LV size and function were measured in 5 groups of rats: (1) obese male spontaneously hypertensive heart failure rats (SHHF) at 9 months (n=10), (2) SHHF at 13 months (n=12), (3) SHHF rats treated with an MMP inhibitor during months 9 to 13 (PD166793 5 mg. kg(-1). d(-1) PO; n=14), (4) normotensive Wistar-Furth rats (WF) at 9 months (n=12), and (5) WF at 13 months (n=12). Plasma concentrations of the MMP inhibitor (116+/-11 micromol/L) reduced in vitro LV myocardial MMP-2 activity by approximately 100%. LV function and geometry were similar in WF rats at 9 and 13 months. LV peak +dP/dt was unchanged at 9 months in SHHF but by 13 months was reduced in the SHHF group compared with WF (3578+/-477 versus 5983+/-109 mm Hg/s, P
Conclusions: MMP activity contributes to LV dilation and progression to LV dysfunction in a rodent HF model, and direct MMP inhibition can attenuate this process.