Extensive Annular Calcification and Abscesses

ANNULAR DECALCIFICATION

The calcification process is often associated with a degenerative valvular disease with preserved pliable leaflets ( Fig. 9-1 ). In most patients it is limited to the annulus but may extend to the leaflet tissue, the ventricular myocardium, and/or the papillary muscles, raising the question of whether the calcium formation should be completely excised before a reconstructive valve procedure is performed, or partially excised, or even left in place followed by a palliative valve procedure. Herein we describe the complete excision of the calcium formation and annular reconstruction, which is our preferred technique in most instances.

The calcium formation is generally encapsulated into a fibrous sheath that can be easily dissected, thus allowing the calcium formation to be removed “en bloc” .

In the typical setting of extensive calcification of the posterior annulus associated with a P2 prolapse, the base of the posterior leaflet is first detached from the calcium bloc and the prolapsing segment is resected (b) . This provides adequate exposure of the calcified annulus ( Fig. 9-2 ).

Decalcification is initiated by incising the endocardium at the atrial and ventricular limits of the calcium formation using a sharp blade knife (a) . The tip of the blade should be oriented in a way that the surrounding tissue is separated from the calcium bar (inset) . Preserving the thin fibrous sheath encapsulating the calcium bar allows an en bloc resection without calcium fragmentation, thus avoiding the use of rongeurs (b) . The dissection is performed by developing a circumferential plane from one extremity of the calcium bar towards the other end, ensuring the entire calcium bloc is removed. The removal of calcium facilitates the exposure of the atrioventricular connective tissue and fat, which contain the circumflex artery and the coronary sinus. The left atrial and ventricular edges are usually covered with a fibrous tissue strong enough to hold the sutures used for the reconstruction of the annulus (inset) .

DEBRIDEMENT OF ANNULAR ABSCESSES

Several types of annular abscesses can be observed in bacterial endocarditis. The lesions affecting the anterior annulus are usually extensions of vegetations and abscesses involving the aortic valve. The lesions affecting the posterior annulus are usually extensions of vegetations involving the posterior leaflet. The resulting abscess may extend to the adjacent myocardium. The operation is carried out step-by-step with the following special precautions to prevent widespread contamination of the surrounding tissues.

• A separate operating table and instruments are used for the debridement.

• The surgeon should wear two pairs of gloves.

• The edges of the surgical field and the left atrium should be protected by Betadine-impregnated towels.

• As soon as the lesions are exposed, multiple specimens should be harvested and sent to bacteriology and pathology for analysis.

• Debridement consists of excising with scissors all infected and necrotic tissues until healthy tissues are exposed ( Fig. 9-3, a, b ). Curettes should be used with caution as they may spread the infection by destroying the organized underlying tissue. During this process, instruments are dipped in Betadine at repeated short intervals.

  

• Once all infected tissues have been removed, the towels protecting the edges of the surgical field and the instruments are removed and replaced by new drapes and new instruments while the surgical team changes gloves.

• Application of local antiseptic solution at repeated intervals is carried out during the entire reconstruction phase.