CHAPTER 17: ASSESSMENT OF MECHANICAL CIRCULATORY SUPPORT DEVICES
1. The most probable mechanism implicated in the development of significant AI after institution of full LVAD support is:
a. Presence of endocarditis
c. Exposure of closed valve to continuous systolic rather than diastolic pressure
d. Aortic leaflet perforation
e. Aortic leaflet prolapse
c. Exposure of a closed valve to continuous systolic rather than diastolic pressure. Under normal conditions, a closed native aortic valve is exposed to intermittent aortic diastolic pressure instead of continuous systolic pressure.
2. Which factors are associated with possible worsening in TR severity after LVAD implantation?
a. Increased preload to the RV due to an increased in left-sided cardiac output
b. Post-CPB increase in pulmonary vascular resistance
c. Increase in PA pressure and RV dysfunction due the systemic inflammatory response
d. Leftward shift of the interventricular septum caused by LV unloading
3. What is the average peak filling velocity in the inflow cannula of an axial flow device?
4. In order to perform TEE assessment for air entrapment in an LVAD pump after implantation, which echocardiographic window is the most useful?
d. ME RV inflow-outflow view
c. ME AV LAX view. The ME AV LAX view will allow visualization of the left-sided chambers, the LVOT, the ascending aorta, and the outflow cannula. All those are places where air bubbles will collect both downstream and upstream from the LVAD pump.
5. When performing evaluation for presence of patent foramen ovale with intracardiac shunt, the reversal of the left-to-right atrial pressure gradient should be captured by agitated saline contrast study by imaging at the following time:
a. Before application of the Valsalva maneuver
b. During the Valsalva maneuver and before injection of agitated ...