The Ross Operation in Patients With Dilation of the Aortic Annulus and of the Ascending Aorta

Abstract

The Ross operation is being identified as the ideal aortic valve replacement for children and young adults.’ As the use of this operation has increased and as postoperative echocardiographic surveillance has become routine, an incidence of late autograft valve insufficiency has been noted. In some patients this has been progressive and reoperation on the autograft valve with either repair or replacement has been required. Careful longitudinal follow-up has documented that preoperative diagnosis of aortic insufficiency, performance of the Ross operation as a scalloped subcoronary implant or an inclusion cylinder rather than a root replacement, and limited operative experience are associated with an increased incidence of autograft valve failure or the development of 2 + aortic insufficiency.* Patients with significant dilatation of the aortic annulus have not been considered candidates for the Ross operation because the disparity between the aortic annulus and the size of the pulmonary valve can lead to autograft valve insufficiency and early valve failure. Also, in patients in whom an intraaortic implantation technique (scalloped subcoronary or inclusion cylinder) was used, marked discrepancy between the sinotubular dimension of the aorta and of the pulmonary root has been associated with early valve fail~re.~.~ Children and young adults with a bicuspid aortic valve and aortic valve insufficiency with dilatation of the aortic annulus and ascending aorta or aneurysms of the ascending aorta were being denied the benefits of this operation.2 Modification of the Ross operation or additional procedures needed to be developed so that this constellation of pathology could be effectively treated ant1 these patients could have a Ross operation. Initial attempts at our institution, using an external cuff of dacron, were successful in most patients but did not produce a predictable decrease in aortic annulus size and prevent early autograft valve dysfunction in some patients.**”’ A reproducible operative technique that was adaptable to all ages and patient sizes as well as aortic valve and aortic annulus pathology was our goal. An important issue is: if the aortic annulus is to be reduced, what is the appropriate size for an individual patient? The pulmonary valve annulus is not similar to the aortic valve annulus and its size is dependent on preload and right ventricular pressure. In vitro measurements of the pulmonary valve annulus, after mobilization of the pulmonary artery and valve from the right ventricular outflow tract at the time of a Ross operation, show that the pulmonary valve annulus will passively dilate to almost any size. Because of the inherent difficulty in determining the “normal” size of the pulmonary valve annulus and recognizing that the pulmonary artery and its contained valve function very well as an aortic valve and root in patients with a normal” aortic annulus size, we have focused on adjusting the aortic valve annulus to a size that is appropriate for the patient’s body size and “fixing” the aortic annulus at that size. It has been our belief that by restoring the aortic annulus size and preventing subsequent dilatation, patients with a significantly dilated aortic annulus and patients with ascending aortic pathology can have a successful Ross operation. The longterm results should he similar to the results obtained in patients who have aortic valve disease without dilatation of their annulus. David et al“ have also identified an increased incidence of autograft valve insufficiency and autograft valve failure in patients with mismatch of the aortic