DYSTROPHIC CALCIFICATION OF MYOCARDIUM AS CONDITIONING FACTOR IN GENESIS OF CONGESTIVE HEART FAILURE - AN EXPERIMENTAL STUDY

Focal myocardial lesions are consistently present in an inbred strain of Syrian hamsters (BIO 14.6 line) suffering from a hereditary primary polymyopathy. The onset and rapid progression of myocardial degeneration play an eliciting or contributory role in the genesis of congestive heart failure, which is also regularly observed during the advanced stages of this hereditary disease. Under the present experimental conditions, variations in calcium and inorganic-phosphorus intake, as well as parathyroidectomy, influenced the secondary calcification of the myocardial lesions but not the extent of focal degeneration itself. Enhancement of dystrophic calcification accelerated the subsequent development of congestive heart failure, while the prevention of calcific deposits afforded a protective effect. Since an inverse relationship was established between the severity of calcification of the degenerating heart-muscle areas and the progression of healing of these lesions, it is postulated that dystrophic calcification influences the development of congestive heart failure by affecting the normal reparative processes in the damaged myocardium. In fact, it was shown that dystrophic calcification interferes with healing not only mechanically, but also qualitatively it alters the normal healing patterns. Calcification appears to be an important conditioning factor in the genesis of heart failure in the hamster. © 1969.