Ross Procedure in Older Patients
Abstract & Commentary
Synopsis: The Ross procedure may be performed in selected patients older than 60 years without increased risks or complications.
Source: Schmidtke C, et al. J Am Coll Cardiol 2000;36:1173-1177.
The pulmonary autograft for aortic valve replacement (Ross procedure) has mainly been used in young patients because the complexity of the surgery makes perioperative risk higher in older patients; however, the age limit is controversial. Thus, Schmidtke and colleagues compared the results of the Ross procedure in 27 patients older than 60 years of age to 84 patients younger than age 60, followed for a mean of 26 months. Perioperative mortality was zero in the older group and less than 1% in the younger group. Echocardiographic measures of left ventricular and valve function were not significantly different between the two groups except that the gradient across the homograft pulmonic valve was higher in the younger group. The New York Heart Association Functional class was less than class I in almost all the patients and was not different between the two groups. Schmidtke et al concluded that the Ross procedure may be performed in selected patients older than age 60 without increased risks or complications.
Comment by Michael H. Crawford, MD
The use of a pulmonary autograft to replace the aortic valve and a homograft for the pulmonic valve was originated by Donald Ross of London in the 1960s, but it was rapidly eclipsed by the development of mechanical and biological prosthetic valves, which were simpler alternatives for most surgeons. When the long-term results of the Ross procedure were published in the late 1980s, renewed interest in this operation was sparked. The Ross procedure registry now suggests that more than 600 are performed a year at more than 100 centers worldwide. The major indications for the procedure are: isolated aortic valve pathology; prior prosthetic valve failure; endocarditis of the aortic valve only; and athletic young adults where anticoagulation is not desirable, but optimal hemodynamics are important. The Ross procedure results in a better hemodynamic outcome than a bioprosthesis and does not require anticoagulation. Also, long-term durability is excellent with reported 20-year freedom from re-operation rates of 75-80%.
These attractive features would make the Ross procedure ideal for older patients were it not for the complexity of the surgery. In order to avoid the need for anticoagulation, older individuals are often given bioprostheses, but then they face the possibility of replacement at an advanced age if the tissue valve fails before they die of other causes. Re-operation at ages older than 70 years have a 15-25% reported mortality. These considerations prompted the present study.
Their outstanding results with zero perioperative mortality and excellent functional class in patients aged 61-71 years with about equal numbers of men and women, is remarkable. Such results speak to their experience with this operation, but also to their patient selection. Patients with extensive three-vessel coronary disease were excluded, as were patients with multivalve disease, ejection fraction less than 40%, disease of the pulmonic valve, severe aortic root calcification, and reduced general health. Most of their patients had aortic stenosis and were NYHA functional class II. Although no data on cognitive state are given, it is noteworthy that bypass time averaged more than 200 minutes in both groups, but was not different between the older and younger patients.
The only clinical or echocardiographic measurement difference between the young and older patients was the gradient across the pulmonic homograft—it was greater in the young group and was weakly correlated with years since operation. This suggests that in the younger patients a more profound immune reaction may be mounted against the homograft. Although in most long-term data, re-operation because of aortic autograft problems is more common than re-operation for pulmonic homograft problems. Thus, this reaction to the homograft may be of little clinical consequence.
In summary, the advantages of the Ross procedure— autologous tissue, long-term viability of the graft, optimal hemodynamics, resistance to infection, no valve noise, low primary failure rate, no anticoagulation and very low thromboembolic rates—make it an ideal operation for isolated aortic valve disease if the patient is otherwise robust and meets the inclusion/exclusion criteria. Based upon this study, ages 50-70 would not seem to be a contraindication alone.