Operative Management
All cases were performed with median sternotomy. Myocardial protection
was moderate systemic hypothermia with primarily retrograde cold blood
cardioplegia given every twenty minutes.
Infection extension over the left atrial roof commonly occurred and was
debrided completely including the aorto-mitral curtain if necessary.
Penetration into the ventricular septum was aggressively debrided down
to healthy looking muscle. Rebuilding the heart depended on how much was
removed. With mitral valve involvement, valve repair or replacement was
performed before proceeding to the root reconstruction. The left atrial
roof and curtain was rebuilt with autologous or bovine pericardial
tissue.
Sizing of the aortic homograft was performed on the basis of echo
measurement of the aortic annulus and directly. If all sizes were
available, the largest possible size was chosen.
Interrupted 4-0 polypropylene sutures were placed around the debrided
aortic root and curtain. Incorporating a 5 mm wide strip of bovine
pericardium on the outside of the root added strength and hemostasis so
each stitch was passed through the pericardium as it was placed. The
sutures were placed through the homograft from the inside out. The
homograft was oriented anatomically with donor mitral matching recipient
aortomitral curtain and the sutures were tied.
Coronary buttons were reimplanted into the sites of the homograft
coronary stumps with continuous 5-0 polypropylene. The distal end of the
homograft was trimmed and sewn to the native aorta with continuous 4-0
polypropylene.
In the majority of the patients, the hemostasis was expected to be
challenging due to the combination of the preoperative deconditioning
due to infection, friable tissue, and technically demanding and lengthy
operation. Therefore, a Cabrol patch with Cooley fistula was often
applied preemptively. This was performed with a large patch of bovine
pericardium sewn to the homograft superiorly, right ventricle outflow
tract and right atrium inferiorly, the main pulmonary trunk medially,
and superior vena cava laterally, creating a closed space around the
root. A small right atriotomy was made before closing this closed space,
creating a perigraft to right atrium shunt.
Postoperative conduction disorder was highly expected due to radical
debridement of infective tissue, so permanent epicardial pacing
electrodes were often preemptively placed.