| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
J Thorac Cardiovasc Surg 1994;108:786-787
© 1994 Mosby, Inc.
LETTERS TO THE EDITOR |
Clinic for Cardiovascular Surgery a
Department of Cardiology b
University Hospital
Zürich, Switzerland
To the Editor:
Homograft replacement of the aortic valve is a recognized procedure in the surgical treatment of aortic valve disease It offers some solutions and improvements for the problems encountered after prosthetic valvular replacement: better hydraulic performance (even in small sizes), reduced thromboembolic complications, resistance to infection, and acceptable valve durability. Main indications for homograft valves include aortic valve replacement during active endocarditis, aortic root abscess with annular destruction, and aortic valve replacement in young patients and women of childbearing age. Homograft implantation is also a valid alternative to use of a bioprosthesis in patients in whom anticoagulants are contraindicated. With the widespread use of homografts, associated complications have become apparent. Recent reports include dynamic obstruction, degenerative and infective processes, and pseudoaneurysm formation. 
1-3
Recently, all our patients who received a homograft in the aortic position between 1991 and 1993 were evaluated by transthoracic or transesophageal echocardiography, or both. The aim of this small report is to draw attention to a current postoperative finding, which consists in a perfused echo-free space, observed by Doppler echocardiography between the aortic homograft and the aortic wall. Postoperative echocardiographic results were analyzed in a series of 20 consecutive patients (mean age 47.5 years, range 26 to 57 years) with replacement of the aortic valve; 15 patients (75%) were found to have one or several small perfused echo-free spaces by Doppler echocardiography. No difference was found between the group of 15 patients with and the group without (five patients) perfused spaces regarding the diameter of the homograft (23 versus 22 mm) and the postoperative mean systolic pressure gradient (14 versus 9 mm Hg). No other significant hemodynamic changes were seen in the presence of echo-free perfused spaces, especially no obstruction of the left ventricular outflow tract. Preoperative infection of the aortic root and anulus was more frequent in patients having echo-free perfused spaces than in patients without endocarditis.
The location of the echo-free perfused space corresponded with the previous location of the abscess/perivalvular leak in seven of nine cases. In all cases, continuous wave Doppler echocardiography demonstrated two distinct systolic jets, one through the valve homograft and another through the proximal suture line into the perfused recesses. Fig. 1 summarizes the main findings of an echo-free perfused space after homograft replacement of the aortic valve. Although no significant difference was noted in the technique of implantation (composite tube/valve homograft or single homograft), echo-free perfused spaces were more frequently observed after multiple previous aortic valve/root operations. No difference was noted in the prevalence of echo-free perfused spaces regarding the technique for sewing the proximal suture line, either with continuous 4-0 monofilament polypropylene 4 or with interrupted 3-0 Ti-Cron sutures (Davis & Geck, Danbury, Conn.) reinforced with pledgets.
|
Barbetseas and associates 5 reported on pseudoaneurysms after composite graft replacement of the ascending aorta and the aortic valve, but their observation does not completely correspond with the finding after aortic homograft replacement; for this reason we prefer the term perfused echo-free spaceor perfused recesses. In fact, the anatomy is a perfused space between the native aortic wall and the wall of the aortic homograft with systolic and diastolic blood flow arising from the left ventricular outflow tract. Contrary to other authors' observations, the ascending aorta was never enlarged in our patients.
Although the follow-up of this series is short, no repeat operations have been necessary so far. However, this observastion does not allow us to judge the prognostic significance of this finding: in the series of Barbetseas, a small echo-free perfused space was observed in 81% of all patients after composite graft replacement. Since we started with homograft techniques, the surgical skill has evolved; routine use of fibrin glue and gentamicin sponges at the site of previous aortic annular abscesses may be a substantial improvement in the surgical technique.
References
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |
