Operative risk
The operative risk for the Ross Operation has steadily decreased and is now similar to
risk for an isolated aortic valve replacement. The 30 day mortality at the
University of Oklahoma is 4.6%, with a mortality of 1.2% in the intra-aortic implant
(scalloped sub-coronary and inclusion cylinder). The operative mortality for the
Ross Operation at our institution during the past five years is 2.1% (4 deaths in 186
patients). The thirty-day mortality as reported to the International Ross Registry
is 2.6% for the past 10 years (74 deaths in 2836 patients).
Early Autograft Valve Failure
Autograft valve failure or dysfunction requiring replacement of the autograft valve at the
time of operative insertion or reoperation within six months of the original Ross
Operation is rare. At our institution, this has only occurred on one occasion, the
second patient in our operative series. This event has not been reported in any
significant numbers in the literature, and in the International Ross Registry since 1987
in 2836 patients, the one-year rate of explant is 0.5% and is 7% so far at ten
years.
Late Autograft Valve
Dysfunction
Accurate information concerning the incidence of late autograft valve dysfunction is
difficult to obtain as there are few longitudinal studies that include echocardiographic
assessment of valve function in their patients. In our series of 324 patients
operated between August, 1986 and June, 1998, 18 patients (6% of the 319 operative
survivors) have required autograft reoperation for progressive autograft
insufficiency. Two of these patients developed endocarditis, and one had valvar
degeneration secondary to systemic lupus erythematosus; the remaining 15 patients had
either technical errors at the time of their operation (3 patients) or developed
progressive autograft valve insufficiency from annular dilatation and leaflet prolapse (12
patients). The actuarial freedom from autograft valve reoperation was 86% + 4% at 8
years. Echocardiographic assessment of autograft valve function demonstrates that
97% of the root replacement patients have had no change in their autograft valve function
during their period of follow-up and only 1% (3 patients) have had an increase of
autograft insufficiency to 3+. The intra-aortic implants (scalloped sub-coronary and
inclusion cylinder) have had no change in the autograft valve insufficiency in 86% of the
patients and 8% have increased to 3+.
To assess those patient and operative factors that are associated with autograft valve
reoperation or the development of autograft insufficiency of 2+ or more, a multiple
logistic regression analysis of this patient population was conducted. The
preoperative diagnosis of aortic stenosis (odds ratio 3.4, 95% CL: 1.3-8.7) and
implantation technique of root replacement vs inclusion cylinder or scalloped
sub-coronary, (odds ratio 2.2, 95% CL: 1.2-4.2) were associated with a decreased
likelihood of developing autograft valve insufficiency or requiring autograft valve
reoperation [1]. This information has led to a modification of the
management of patients who have aortic valve insufficiency and an aortic annulus
significantly larger than expected, based on the patient's body surface area.
Currently all patients with a dilated aortic annulus have had an aortic annulus reduction
and fixation of their aortic annulus at the time of pulmonary autograft root replacement
of their aortic valve. Short-term results in 53 patients managed in this fashion
demonstrate a significant improvement over prior results in patients with aortic valve
insufficiency as their primary diagnosis [7].
Homograft valve
function
Pulmonary homograft reconstruction of the right ventricular outflow tract is
utilized in most Ross Operations and in our patient series it was used in 321
patients. In the 319 operative survivors, the actuarial freedom from reoperation on
the homograft was 92% + 4% at 8 years. Eight patients or 2.5% have required 9
homograft reoperations. In each patient, the pulmonary homograft developed stenosis
in the pulmonary artery conduit requiring replacement. In two, the pulmonary
stenosis developed within one year of their Ross Operation and this accelerated
degeneration of the conduit is thought to be an immunologic response to the
homograft. Late echocardiographic assessment of homograft valve function
demonstrates that a number of pulmonary homografts have reduction of the pulmonary valve
annulus and of the distal homograft pulmonary artery. The actuarial freedom from
reoperation or a peak instantaneous doppler gradient of 40+ mmHg in the pulmonary
homograft is 85% + 4% at 8 years. Significant pulmonary insufficiency producing
right ventricular dilatation and dysfunction has not been seen.
Lifestyle
These patients have not required anticoagulation and there have been no thromboembolic
events. The patients have had minimal restrictions on their lifestyle and the
majority are on no cardiac medications. The actuarial freedom from replacement of
the autograft valve in the 319 operative survivors is 94% + 2% at 8 years, and in the 168
children in this series the actuarial freedom from replacement of the autograft valve is
98% + 1% at 8 years. Actuarial survival of the 324 patients is 91% + 3% at 8 years.
The long-term, excellent function of the Ross Operation in our patients and similar
results that are being reported by other investigators strongly suggest that in children
and young adults, the Ross Operation may be the preferred procedure for replacement of the
aortic valve.
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