Experimental and Clinical Performance of Long-Term Cannulas for Mechanical Circulatory Assistance

Mechanical circulatory assistance with left ventricle assist devices (VADs) can be used for hemodynamic stabilization in patients waiting for heart transplantation. In this application the VAD is connected to the heart with the use of special cannulas. The purpose of this work is to present in the performance of long-term cannulas designed for pediatric patients undergoing circulatory assistance. Pressure drop of cannulas with different sizes were tested using a mock loop of the pediatric arterial circulation. Considering a flow range of 0.52–1.25 L/min the pressure drops obtained was 9.43 to 22.1 mm Hg, respectively. Good clinical results were obtained with cannulas associated with a centrifugal pump or DAV for a period of approximately 4–64 days, with no thrombus formation on the tips of the cannulas or bleeding. The implantation of cannulas proved to be technically feasible and their removal was easy to perform in cases of ventricular recovery or transition to a long-term assistance device.