Background: Renal failure is a well-established cardiovascular risk factor. We hypothesized that uremia negatively affects post-myocardial infarction (MI) remodeling and left ventricular (LV) function and examined the pathohistological correlations.
Methods: Subtotally nephrectomized rats (SNX) and controls with MI only (MIC) were examined 1, 4 and 8 weeks after MI. MI size, ejection fraction (EF), cardiac fibrosis, vascular density and cardiomyocyte density were studied.
Results: The extension of MI was 0.08 +/- 0.02 in SNX versus 0.06 +/- 0.02 in MIC rats (p < 0.031). Prior to MI, EF was comparable in SNX and MIC (74 +/- 3 vs. 72 +/- 2%, n.s.). Despite a relatively small infarct size EF in SNX decreased to 58 +/- 4% 1 week after infarction and progressively worsened to 51 +/- 4% after 8 weeks. In MIC animals EF only slightly decreased 1 week after MI (70 +/- 3%) and remained unchanged at follow-up. In SNX animals LV end-diastolic diameter continuously increased following MI throughout the study period indicating accelerated remodeling. Furthermore, accelerated myocardial fibrosis was already notable 1 week after MI in SNX animals and the volume density of capillaries and cardiomyocytes was significantly lower in SNX rats.
Conclusion: MI in experimental uremia is associated with progressive impairment of LV function, LV dilatation and accelerated myocardial fibrosis.
Copyright 2010 S. Karger AG, Basel.