Coronary microcirculation remodeling in patients with idiopathic dilated cardiomyopathy.

LAGUENS RP; ALVAREZ P; VIGLIANO CA; CABEZA MECKERT P; FAVALORO LE; DIEZ M; FAVALORO RR

CARDIOLOGY

KARGER

Lugar: Basel; Año: 2011 vol. 119 p. 191 - 196

0008-6312

BACKGROUND: In patients with idiopathic dilated cardiomyopathy (IDCM), the myocardial blood flow is markedly depressed. The presence of alterations in the number and length of the coronary microcirculation has not been explored. METHODS: In explanted hearts of 6 patients with IDCM and in 6 normal control hearts, the arteriolar length density and capillary numerical density were determined in sections stained with orcein (vessels 50-200 microns in diameter), for smooth muscle actin (vessels 6-50 microns in diameter) and CD34 (capillaries). RESULTS: No difference with normal hearts was observed in capillary numerical density and in length density of vessels above 50 microns in diameter. In IDCM, more than 50% of arterioles below 50 microns in diameter displayed an incomplete smooth muscle wall, and length density, especially for arterioles between 6 and 20 microns in diameter, was significantly lower (42.84 ± 8.51 mm/mm3) than in controls (75.34 ± 3.05 mm/mm3), p = 0.001). CONCLUSIONS: In IDCM, arterioles below 50 microns in diameter display an incomplete smooth muscle wall and a significant decrease in length density. These observations provide an anatomical basis for a decreased coronary flow reserve in IDCM.