A 72 year-old female with acute prosthetic aortic root endocarditis and systolic congestive heart failure underwent a homograft revision within 6-months. Initially she underwent root replacement with a straight composite graft for a severely stenotic aortic valve and root dilatation. Over a 6-month period, she developed a progressively audible holosystolic murmur. Echocardiography demonstrated a vibrating stuttering of the prosthetic valve cusps on M-mode. This was exaggerated with aortic root endocarditis vegetations on cusps. We hypothesize that this repetitive severe turbulent flow related to a Venturi effect damaged the straight tube graft-aortic root and prosthetic valve cusps in our case.
The sinuses around the cusps are well known for their ability to help absorb aortic root pressure, especially during diastolic phase to prevent damage to aortic root area. They may also help protect the aortic root from damage of high velocity jet during systolic cycle if there is a supravalvular obstruction downstream. We hypothesize that patient with straight Dacron tube graft used for repairing the aortic root aneurysm with no sinuses around cusps are more likely to develop endocartitis of aortic root from venturi effect across the cusps.
For full text: click here
(Author: Maqsood M. Elahi, Dennis Ho, Kenton J. Zehr