Predestinating Role of Cardiac Ganglia on Heart Life Expectancy in Rabbits After Brain Death Following Subarachnoid Hemorrhage: An Experimental Study

Abstract

BackgroundCardiac ganglia are rechargeable batteries of the heart. The essential role of cardiac ganglia on cardiac life expectancy has not been examined following brain death. The aim of this study was to determine cardiac ganglia numbers and neuron density following subarachnoid hemorrhage (SAH). MethodsTwenty-five hybrid rabbits were grouped as control (n = 5), sham (n = 5), and SAH (n = 15). The SAH groups’ animals were subjected to injections of lethal dose of 2.00 cc autologous blood into their cisterna magna until linear EEG was obtained. The hearts of all animals were extracted following intracardiac formalin injection and examined. Cardiac ganglia and normal/degenerated neuron densities of cardiac neurons were recorded. ResultsThe mean volume of normal neuron density of ganglia was 6.980 ± 830/mm3, and the degenerated neuron density of ganglia was 3 ± 1/mm3 in the control group, 6134 ± 712/mm3; 23 ± 9/mm3 in the sham group, 3456 ± 589; 1161 ± 72/mm3 in the surviving group; and 1734 ± 341/mm3, 4259 ± 865/mm3 in the dead animals in the SAH group. The algebraic results of heart work capacity (Wh) were estimated as 1375 ± 210 Wh in the control group, 1036 ± 225 in the sham group, 800 ± 110 Wh in the surviving group, and < 100 ± 20 in the dead animals in the SAH group. Degenerated cardiac neuron density/Wh correlation is statistically meaningful between the dead in the SAH group versus the SAH-surviving, sham, and control groups (P < .0005). ConclusionsNormal cardiac ganglia numbers and/or cardiac ganglia neuron density may be related to cardiac survival following brain death after subarachnoid hemorrhage.