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

Abstract

Electronmicroscopic (EM) evaluation of selected vital organs (liver, kidney, lung) informs us about otherwise hardly detectable changes during total artificial heart (TAH) pumping. In our experiments, we compared 2 groups of long-surviving animals in which the TAH TNS-BRNO pneumatic device was implanted (TNS-BRNO-II and VII in 45 experiments, TNS-BRNO-III in 1 experiment, and TNS-BRNO-VIII in 1 experiment). In 4 experiments, the Rostock TAH (NABEL, TAH Research Center, Rostock, Germany) was implanted. One group of 22 animals with an average survival of 162 days (the longest, 293 days) was submitted to an antihypertensive treatment; another 1 of 29 calves with an average survival of 98 days (the longest, 173 days) was untreated. The evaluation was performed using a scale (0 to 3) based on very precisely fixed criteria. EM pathologic changes documented various stages of ischemic damage. Except for the liver, no significant difference was found between both groups, despite the substantially prolonged survival in the treated group. Very important was the general state of mitochondria, endoplasmic reticulum, and nucleus. Further, the state of glomerular podocytes in the kidney and the state of interalveolar septa and of pneumocytes constituting the air-blood barrier for gas exchange in the lungs are especially important. In some animals of both groups, the EM findings were completely normal, especially in the lung.

Total Artificial Heart: The Adaptation and Pathophysiological Deviations in the Recipient

“…But even here, the adequate antibiotic treatment and the stimulation of the immune defense allowed prolongation of survival (15). The electronmicroscopical evaluation of some vital organs (lungs, kidney, and liver) possible in long‐term surviving calves has shown a remarkable resistance of the lung tissue against hypoxia and against the ischemic damage of the cells in lungs (16).…”

Czech Marathon in the Research of Heart Assist Systems and Total Artificial Heart

“…Based on our intense study of pathogenesis of high arterial and venous pressure, especially in the later stages of pumping, we have developed pathophysiological principles to prevent it (19). The analysis by electron microscopy showed more expressed lesions in liver and kidney than in the lung (20). The study of the TAH infections enhanced the use of more specifically developed antibiotics focused exclusively to the slime biofilm protected bacteria on the diaphragm.…”