Atrophied hearts grow with inserted balloom

J Mol Cell Cardiol

23 (Supplement

Changesin interstitial

V) (1991)

collagen in the humanmyocardium after myocardial infarcti-

011.

Paul G.A. Volders, Miek G. Havenith, Jack P.M. Cleutjens, Mat J.A.P. Dsemen. Department of Pathology, University of Limburg. P.O. Box 616. 6200 MD, Maastricht, The Netherlands. Cardiac hypertrophy after myocardfal infarction (MI) induced by ligation of the left coronary artery in the rat is accompanied by an increase in interstitial measured by the hydroryproline collagen. Recently increased collagen amounts, content, were reported in the hypertrophied human heart after (MI). We studied the changes in collagen content in the human myocardium after infarction using the Sirius Red technique, which enables to quantitate and localize the interstitial collagen content. The relative Sirius Red positive area was determined by computerized morphometry on paraffin embedded sections of the non-infarcted septum of human autopsy hearts. Only hearts with a first MI in the anterior or posterior left ventricular wall were selected (n-13, weight 538illOg. meanitsd). Hearts with a weight of less than 400 g were used as controls (341*49g, n-4). The collagen content in the mid-septal area was significantly increased in the infarct group as compared to the controls: 12.9i5.42 v8 7.8*2.6X. These data indicate that the collagen content in the human myocardium after MI is not only increased in the infarcted area but is also significantly increased in the non-infarcted regions of the heart.

P14 RESPONSIBILITY OF PATHOLOGICALMICROVESSELREACTIONS FOR TRB DEVELOPMENT OF MYOCARDIALFIBROSIS IN SPONTANEOUSLY BYPERTBNSIVERATS (SBR) Hans-Jiirgen Herrmann, Ulrike Herrmann, Vera Moritz, Christian Kiihne, Institute of Heart and Circulation Research Berlin 1115, Wiltbergstr.50 and Institute of Microbiology and Experimental Therapy Jena, Germany The pathogenesis of myocardial fibrosis in hypertension is incompletely understood. Using a new preparation method that selectively visualizes the microvessels (mv) within the interstitial reaction 38 male SHR aged 3-78 weeks and 33 normotensive controls were investigated . New measuring procedures were applied to objectify the mv reactions and the area densities of interstitial tissue distinguishing its thick and thin fibers.-In the manifest phase of hypertension there are distinct topological and quantitative relations between the increase in interstitial tissue and pathological mv reactions to be interpreted as consequences of a chronic contraction. These mv reactions especially include very small mv that elude from detection after conventional stainings. There is also a topological relation between the mv reactions and alterations of heart muscle cells resulting in a replacement fibrosis. The highest area densities of the total interstitial tissue and its thick collageneous fibres were found in the endocardial third of the free wall, the basal and the apex region. It is concluded that pathological mv reactions are the deciding cause of both the focal interstitial fibrosis and the replacement fibrosis.

P15

ATROPHIED HEARTS 6ROU UITH IHSERTEO BALLOOW. I. Klein,

C. hong & S.S.

sdreiber. Cornell Ilniversity, Universit y of Pittskrrgh L Hew York Uniwrsity 8chools of Nedicine t WI Nediwi Ctr. NV ly bat, d (Ipc Althwgk cavliec trmbspionts spontmeous histologically normal, theyorcnotmorkingqpinstaioadaul~ atrophy. ye exmined the effect of a left ventricular isouolvic balloon on the dmuelepment of ~tmphy. On dq 0, the right of the donor LU ws 3B7i 14 m9 in the unloaded awlsha ioadedws21-22f3caporcd to4Oi4 intheballoen lwdad hmmts. LU #UW content
S.61