To determine whether or not myocardial fibrosis in the left ventricle
increases after exposure to asbestos fiber, we studied myocardial fibr
osis in 42 autopsied hearts: 17 of asbestosis (AS) and 18 of chronic p
ulmonary disease (CP) without pneumoconiosis, Seven patients with extr
a-cardiopulmonary disease were used as a control group (CONT). The ext
ent of myocardial fibrosis in the left ventricle was significantly gre
ater in the AS group compared to the other groups (AS 3.6 +/- 1.3% vs.
CP 2.4 +/- 1.0% vs. CONT 1.6 +/- 0.8%). There was a significant diffe
rence in the appearance ratio of focal fibrosis between the asbestosis
group and the other groups, Focal fibrosis was observed in none of 7
control patients, in 3 of 18 patients with chronic pulmonary disease a
nd in 9 of 17 patients with asbestosis, We concluded that characterist
ic myocardial fibrosis was observed in humans after long-term asbestos
exposure.