Abstract
Effects of the left heart bypass (LHB) by the left atrium (LA) to the aorta (AO) shunt on the heart were evaluated by measuring such parameters as tension time index (TTI), diastolic pressure time index (DPTI), DPTI/TTI ratio, coronary blood flow and myocardial oxygen consumption (MVO2) in open-chest dogs. A pneumatically driven bypass pump made of polyurethane was utilized in this study. No significant change of MVO2 was observed with surgical maneuver to connect the LA-AO LHB pump to experimental animals. During synchronous pumping of LHB, TTI decreased by 35%, MVO2 decreased by 56% of the control and DPTI/TTI ratio increased by 79%. However, coronary flow decreased by 35%, presumably due to autoregulation mechanism of the coronary circulatory system. Both synchronous and asynchronous LHB demonstrated the same level of effect in volume unloading. However, significant diastolic augmentation was noted only in the former. LA-AO LHB, which has a sufficient supporting effect and does not damage the ventricular wall, was considered to be very useful for temporary support for the failing heart, especially for postoperative low output state.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
