| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
J Thorac Cardiovasc Surg 2001;121:398-399
© 2001 The American Association for Thoracic Surgery
Letters to the Editor |
Pediatric Cardiology and Cardiac Surgery
University of Bologna
Policlinico S. Orsola 40138 Bologna, Italy
To the Editor:
We read with interest the article by El-Najdawi and colleagues
1 about the long-term results of a large cohort of patients undergoing repair of partial atrioventricular (AV) canal. The authors describe the impressive Mayo Clinic experience of 334 patients, finding age at operation less than 20 years and closure of the cleft as independent variables associated with longer survival, lower incidence of arrhythmias, and possibly lower incidence of reoperation. However, we believe some other issues may have had an impact on the results of this study.
First, the incidence of Down syndrome seems to be much lower than might be expected in an unselected population of patients with partial AV canal (5% vs 36% as reported in the Baltimore-Washington study 2 and 28% at our institution from 1983 to 2000). As a result of this low incidence, the impact of genetic factors on the long-term outcome and reoperation rate in this kind of patient probably was underestimated. Indeed, non-Down AV canal has a higher incidence of associated left heart lesions, 3 a significant threat to the long-term freedom from reoperation. Thus, the population studied by El-Najdawi and colleagues may be not representative of the whole spectrum of patients with this type of congenital heart defect. Moreover, the slightly higher than usual median age to operation (8 years) suggests that another relatively small, but clinically significant, subgroup of patients may have been overlooked.
It is our experience, already enlightened by groups in both Boston 4 and Rome, 5 that some patients with partial AV defect may present early with signs of heart failure, usually within the first year of life. Being unresponsive to medical treatment, they may require early surgery (even a Norwood-type approach in some cases), featuring a very high risk for further reoperations. This risk is mostly due to the presence of associated left heart lesions (usually left ventricular outflow tract obstruction and coarctation of the aorta) with varying degrees of left ventricular hypoplasia. If we take this group into account, the Kaplan-Meier curves for freedom from reoperation may reveal non-Down partial AV canal as a less benign lesion, leading to redo surgery in up to 38% of cases within 15 years (unpublished data).
In conclusion, we believe that this article underestimates the impact of Down syndrome as an important prognostic factor, perhaps due to a selection bias bound to a single-institution study. For the same reason, an important subgroup of patients with complex associated anomalies and early presentation (and an even greater impact of genetic factors) may have been underestimated as well. The authors are to be commended for the large number of patients in their study and for undertaking difficult research going to the roots of modern cardiac surgery, but a more accurate description of the study group is probably required. As always, it is the reader's duty to view the results of this valuable article within the framework of the already published scientific evidence and personal experience.
12/8/111049
doi:10.1067/mtc.2001.111049
References
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |
