Changes of the Cardiac Function and Circulating Catecholamine Level Under Ventricular Assist Device Installed in Acute Cardiogenic Shock Induced Experimental Animals

ABSTRACT

PURPOSE: The recent rise in the number of patients visiting emergency rooms with acute cardiogenic shock underscores the need for immediate efforts to develop affordable circulatory assist devices. Recently, a pneumatic pulsatile ventricular assist device (VAD) named DKUH-75, has been developed by the authors. We evaluated the feasibility of the DKUH-75 VAD in pigs placed into an acute cardiogenic shock state following myocardial infarction through a novel coronary artery ligation method involving ischemic preconditioning. METHODS: Acute cardiogenic shock was induced in 5 YorkshirexLandracexDuroc pigs by ligating the left anterior descending coronary artery via the ischemic preconditioning process. Afterward, the DKUH-75 VAD was implanted one hour after the onset of shock. Hemodynamic variables, echocardiographic findings and the level of circulating catecholamine were ascertained one hour after VAD installation. RESULTS: Systolic and mean systemic arterial pressures were increased while pulmonary arterial pressure were decreased one hour after the VAD implantation. LVEDP decreased, and the cardiac index increased significantly. In echocardiographic findings, the left ventricular end systolic dimension decreased after VAD implantation, and the fractional shortening and the ejection fraction increased significantly. The level of circulating catecholamine was increased one hour after the coronary artery ligation and was decreased one hour after VAD implantation, but these trends did not reach a statistical significance. CONCLUSION: The DKUH-75 VAD may help in the recovery of myocardial function, and we postulate that early VAD installation can improve outcome for the cardiogenic shock patients in the emergency room by preventing further development of congestive heart failure. However, further experiments are needed in order to demonstrate the statistical significance of the observed results.