Methods from the Theory of Random Heterogeneous Media for Quantifying Myocardial Morphology in Normal and Dilated Hearts

In the present study, descriptors from the theory of random heterogeneous media were used to characterize the morphology of the myocardial interstitial space in histological sections from hearts of healthy subjects and of patients with idiopathic dilated cardiomyopathy (DCM). Histological sections from resected DCM hearts (n = 9) were compared with donor hearts showing no signs of cardiac disease (n = 6). From control to DCM, the area fraction phi(1) of the interstitial space increased from 0.13 +/- 0.05 to 0.27 +/- 0.08, the chord-length z from 1.67 +/- 0.61 to 5.56 +/- 1.78 microm, the pore-size delta from 0.72 +/- 0.13 to 1.73 +/- 0.40 microm, the distance r (min) of the first local minimum in the two-point correlation function from 10.99 +/- 1.09 to 18.57 +/- 4.36 mum, whereas specific interface length s and decay-rate gamma of the lineal-path function decreased from 0.20 +/- 0.07 to 0.16 +/- 0.04 microm(-1) and from 0.39 +/- 0.09 to 0.16 +/- 0.05 microm(-1), respectively. All descriptors (except for s) were significantly different (p < 0.05) between control and DCM, reflecting an increasingly heterogeneous morphology in DCM hearts. Our results suggest that (1) descriptors originally developed to characterize the morphology of random heterogeneous media are well suited for histomorphometry of DCM, and (2) among the descriptors studied, either pore-size delta or chord-length z qualify best to discriminate between control and DCM hearts.