Freehand homograft aortic valve replacement--the learning curve: a technical analysis of the first 31 patients.

The technique for implanting the homograft aortic valve is significantly more complex than that of either the bioprosthetic or mechanical valve. During development of the procedure, errors of technique were committed; a critical analysis of the learning experience is presented. In the initial 31 patients, the following problems were encountered: mitral stenosis secondary to inadequate debulking of the homograft (1 patient), prolapse of a single homograft leaflet necessitating valve replacement three days later (1 patient), incorrect homograft orientation with torsion in a calcified aorta necessitating subsequent replacement (1 patient), and aortic sinus perforation (thawing injury) (1 patient). In addition, another 4 patients had diastolic murmurs thought to be secondary to inadequate tension setting of the homograft commissural posts. From this experience, several important technical considerations for homograft replacement of the aortic valve were noted: use of interrupted subannular sutures; careful inspection for aortic perforation (thawing); extensive trimming of the homograft septum and mitral remnant; orientation of the homograft to the recipient aorta to obtain the best commissural and sinus alignment; selection of another type of valve if the size of the recipient annulus is greater than 27 mm; retention of the homograft sinus, which orients to the recipient non-coronary sinus (for a calcified aorta); and exaggerated tension on the homograft commissural posts before initiation of the second suture line. There has been 1 hospital death and no late deaths. Adherence to rigid principles of technique has resulted in no further valve replacements and no incidences of valvular leakage at early or late follow-up.