Sangik Park MD, Presenter: Nothing to Disclose

Dong Hyun Yang MD, Abstract Co-Author: Nothing to Disclose

Joon-Won Kang MD, Abstract Co-Author: Nothing to Disclose

Tae-Hwan Lim MD, PhD, Abstract Co-Author: Nothing to Disclose

Subvalvular soft tissue (pannus) formation has been known to be a cause of high transvalvular gradient and necessitate reoperation of valvular replacement. There was lack of data regarding the prevalence of subvalvular pannus during immediate postoperative period. This study aimed to evaluate prevalence and hemodynamic significance of subvalvular pannus in computed tomography (CT) during immediate postoperative period in patients who underwent valve replacement surgery.

During two years, 1057 patients underwent cardiac valve replacement surgery. Among them 203 patients (mean age, 58; 131 men) underwent ECG-gated cardiac CT within 30 days from operation (aortic valve=180, mitral valve=26, tricuspid valve=3, pulmonary valve=1). Presence of subvalvular pannus was evaluated using multiphase cardiac CT images in dedicated workstation. Hemodynamic parameters such as transvalvular pressure gradient and peak velocity of transaortic flow were evaluated using echocardiography and compared them between patient with and without pannus formation. Valve type- and size-matched comparison between pannus and non-pannus groups were done to evaluate the hemodynamic significances of pannus. Geometric profiles of mechanical valves including diameter of valve and opening angle were evaluated. 

Subvalvular pannus was identified in 31 of the 210 valves (14.8%). Among them, 30 were in the aortic location, while the other one was in the mitral location. The mean length, maximal thickness, and involvement angle of pannus were 11.3 mm ± 4.4, 3.1 mm ± 1.2, and 54.8° ± 19.3, respectively. Echocardiographic measurements of peak velocity (pannus group vs. non-pannus group, 2.4 m/s vs. 2.3 m/s, p=0.665), maximum pressure gradient (24.0 mmHg vs. 22.7 mmHg, p=0.5297), and mean pressure gradient (12.6 mmHg vs. 11.9 mmHg, p=0.4671) across the prosthetic aortic valve did not show a significant difference statistically.

Even in immediate postoperative period, subvalvular pannus was not uncommon in this retrospective study group. However, the extent of subvalvular pannus seemed to be small as compared with results of previous study. Patients with subvalvular pannus during immediate postoperative group showed insignificant hemodynamic parameters on echocardiography as compared with non-pannus group.

Cardiac CT was feasible method to demonstrate subvalvular pannus in pateints with prosthetic cardiac valve. 

Park, S, Yang, D, Kang, J, Lim, T, Computed Tomography Evaluation of Subvalvular Soft Tissue in Patients Who underwent Valve Replacement Surgery during Immediate Postoperative Period.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14017681.html