Prognosis and changes of myocardial intersitium before and after ventricular assist device application

Abstract

Objective To investigate the relation between the changes d myocardial collagen content before and after ventricu-lar assist device (LVAD) application and the prognosis in dilated cardiomyopathy. Methods Patients was divided to two groups ac-cording to the prognosis (weaning or transplantation) after LVAD application. Left ventricular samples were collected from the patients (weaning group n= 10, transplanted group n=8) at the time the LVADs were implanted, and again during cardiac transplantation ( n = 8 ). The content of neutral salt soluble collagen (NSC) and acid soluble collagen (ASC) were measured by Sired collagen assay and total collagen and insoluble collagen (ISC) by quantification of hydroxyproline. Moreover, protein quantification of each collagen fraction was performed simultaneously. Results Before LVAD implantation all collagen fraction and their protein contents were higher in the weaning group than that in the transplanted group ( P <0.05), but the difference in the collagen fraction disappeared after LVAD support. Comparison of the pre- and post-LVAD subgroups of the transplanted group showed an increase of NSC and its protein content and total hydroxyproline after LVAD support (P<0.05). Conclusion The significances of myocardial intersititial remodeling in DCM are not identical. Some myocardial collagen and protein content increases may be related to good prognosis. The mechanism of LVAD improving cardiac function may be related to the changes of myocardial intersitial collagen. Key words: Heart assist device; Assisted circulation; Cardiomyopathy, dilated; Prognosis