A Contribution to the Assessment of Pathophysiology in Long-Term Total Artificial Heart Recipients

Electronmicroscopic Changes in Selected Vital Organs After Long‐Term Total Artificial Heart Pumping in Animal Experiments

“…In the treated group, the aim of the antihypertensive treatment was to decrease both the CVP and the arterial pressure, which, after a prolonged TAH pumping, can seriously damage the vital organs, especially the organ microcirculatory structures. The effect of this treatment could be observed in the decrease of the CVP values in the treated group and partially in the protection of the liver tissue from extensive microcirculatory damage, which was, on the other hand, observed by the means of light microscopy in the untreated animals (5,7,10). Also, the prolongation of survival was evident in the treated group.…”

“…Especially in the liver, the changes were mainly caused by the increased CVP with concomitant subsequent stasis in the liver microcirculation with hypoxic damage of the hepatic tissue. The pathogenesis of the CVP increase in the TAH animals has been published elsewhere, and based on this pathogenetic background, we also could perform an essentially successful pathophysiological treatment (5,7,(10)(11)(12). Due to this treatment and also partly due to the systemic antimineralization treatment aimed at the prevention of mineralization of driving diaphragms, we could substantially increase the length of survival (1,2).…”

“…The materials and methods concerning the type of the TAH implanted in our long‐term experiments and the arrangement of the experiments in our 66 animals (65 calves and 1 goat) were published elsewhere (5–10). In this study, dealing with the evaluation of the EM changes of 3 vital organs (liver, kidney, and lungs) in 51 long‐term survivors, we evaluated the EM findings in 22 animals (21 calves and 1 goat) with the antihypertensive treatment (average survival 162 days of pumping, mean ± 59.2 SD; the longest survival 293 days) and in the untreated group.…”

“…The antihypertensive treatment was performed because of our observation of the increased arterial hypertension, and especially of venous hypertension, during a long‐term survival where marked liver damage and partial kidney damage was observed. The detailed methods of application of the antihypertensive treatment also were described in previous publications (5,7,10–12). Therefore, the description of the methods used for the EM evaluation is given in this study.…”