Are You a Candidate?
Indications: The indications for the pulmonary autograft procedure have broadened over time. Current indications for the procedure are outlined in Table I.
| Indications for Aortic Valve Replacement with the Pulmonary Autograft |
|---|
| •Patient (male or female between 11 and 50 years of age) |
| •Isolated aortic valve pathology (male or female) |
| •Endocarditis limited to the aortic root |
| •Athlete or young in whom anticoagulation is contraindicated and optimal hemodynamics is desirable. |
Age and Activity Level. First and foremost, the pulmonary autograft procedure is designed for the young patient presenting with isolated aortic valve disease. The accepted age range for patients having the pulmonary autograft procedure has expanded significantly. The probable reasons for this expanding age consideration are two-fold.
First, early mortality for the operation has fallen as evidenced by the results in the Registry and Second, relative to the growth potential of the pulmonary autograft and success of the operation in children , many surgeons view the procedure as a solution for congenital aortic stenosis that can be performed early in life, and quite possibly eliminate the need for multiple aortic valve replacements. As increasing durability of the operation is evidenced, older patients with more active lifestyles become candidates for the procedure. The pulmonary autograft procedure is certainly indicated for young women of childbearing potential. This relates primarily to the problems associated with the use of blood thinning agents (such as Coumadin) during pregnancy.
One area where the pulmonary autograft procedure is gaining wider acceptance and application is in patients presenting with an infection in their heart (acute bacterial endocarditis). Published data suggests that the re-infection rate for autografts is lower than that of the published alternatives for bioprosthetic valves, mechanical valves, and aortic homografts.
Special consideration should be given to the athlete facing aortic valve replacement. This group, by the very nature of the activity in which they choose to participate, is often not in a position to subject themselves to the risks (increased potential for bleeding) inherent in anticoagulation that accompanies most valve replacement alternatives. In addition, athletes often experience extreme levels of hemodynamic functioning in pursuit of their athletic activities. Studies performed in "highly conditioned" athletes who have undergone the Ross Procedure document a normal hemodynamic response of the autograft to extreme levels of activity. As documented hemodynamically (i.e. physiologic gradients with exercise) and echocardiographically (i.e. normal leaflet mobility and absence of leakage). These two factors make the choice of a pulmonary autograft the optimal choice for aortic valve replacement in this population.
Contraindications: As indications for the pulmonary autograft expand, contraindications decrease, however certain absolute and relative contraindications continue to exist and are listed in Table II. Though, in some cases these contraindications are subjective, they are widely and generally accepted.
| Contraindications for Aortic Valve Replacement with the Pulmonary Autograft |
|---|
| •Advanced three vessel coronary artery disease |
| •Extremes of age (< 3 years or >70) |
| •Extensive multi valve pathology necessitating replacement of one or more valves |
| •Connective tissue disorders such as Marfan Syndrome |
| •Multisystem organ failure (pulmonary, renal, hepatic, etc.) |
Multi-Vessel Disease. In general, the patient that presents with multi-vessel coronary artery disease would not be an appropriate candidate for the pulmonary autograft procedure. Relative to the inherent complexity involved with this operation, and the often-prolonged operative time, a more expeditious implantation should be utilized in the setting of severe coronary artery disease.
Age. It would appear that the pulmonary autograft procedure would be contraindicated in both the extremely young and those of advanced age. Although initial results from the Ross Registry indicate successful application of this procedure in infants, more follow-up is needed to validate long-term clinical outcomes.
Multi-Valve Disease or Pathology. Patients requiring more than one valve repair or replacement at the time of surgery would be considered a contraindication to the Ross Procedure especially in terms of the prolonged operative time a multiple valve replacement operation requires. Moreover, more than one valve repair in one operation presupposes the use of a biologic or mechanical valve for the non Ross-position, thereby negating many of the main benefits of a Ross Procedure.
Diminished Left Ventricular Function. Patients presenting with diminished left ventricular function (decreased heart function) though not an absolute contraindication, should be judged on an individual basis in terms of the longevity of the disease process leading to decreased LV function.
Connective Tissue Disorders. Patients presenting with Marfan syndrome (a hereditary condition affecting the connective tissue, bones, muscles, ligaments, and skeletal structures) are also a population subset not appropriate for the Ross procedure. The pulmonary valve is not a satisfactory substitute for the aortic valve in these patients because the generalized connective tissue abnormalities intrinsic in this disorder are also present in the pulmonary valve apparatus, as well as the aortic valve.
Multi-System Organ Failure. Patients presenting with multi-system organ failure are also not candidates for the pulmonary autograft procedure. This is based primarily on the often-prolonged intra-operative course that the technical complexity of the procedure mandates and the general effects of prolonged cardiopulmonary bypass.
